Publications

Akbarzadeh, M, Oberst, S, Sepehrirahnama, S, Chiang, YK, Halkon, BJ, Melnikov, A & Powell, DA 2022, 'A Numerical Study of Acoustic Radiation Forces for the Contactless Excitation of a Microcantilever' in NODYCON Conference Proceedings Series, Springer International Publishing, pp. 335-345.
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Akhtar, R, Arqam, M, Alam, MS, Rafat, Y & Hameed, S 2022, 'Transportation and Parking Framework for Pollution-Free AMU Campus: A Case Study' in Computational Modelling in Industry 4.0, Springer Nature Singapore, pp. 325-335.
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Arqam, M, Usmani, S, Aberoumand, S & Kumar, V 2022, 'Recent Advancements in PEM Fuel Cell Technologies for Electrified Transportation' in Developing Charging Infrastructure and Technologies for Electric Vehicles, IGI Global, pp. 233-251.
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The interest in developing clean and environmentally-friendly energy devices to be used on vehicles is intensifying because of emissions from conventional internal combustion engines considered as one of the significant contributors to the rapidly changing climate. Fuel cell energy devices, especially the proton exchange membrane (PEM) type, are the solid contender to replace the conventional vehicle propulsion technology in the transport sector. The PEM fuel cell technology needs a lot of efforts to overcome some existing problems such as durability, hydrogen storage, and cost for its successful worldwide commercialisation. This chapter deals with the durability, cost, and performance challenges related to the utilization of PEM fuel cell technology in electrified transportation. Recent advancements concerning the current challenges have been discussed. Moreover, issues of hydrogen storage and infrastructure are outlined.

Hoffmann, F, Wesskamp, V, Bleck, R & Deuse, J 2022, 'Scalability of Assembly Line Automation Based on the Integrated Product Development Approach' in Annals of Scientific Society for Assembly, Handling and Industrial Robotics 2021, Springer International Publishing, pp. 275-286.
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AbstractProduct life cycles change, market developments and quantities are increasingly difficult to predict, as is the case in the production of charging stations. For these reasons, scalable assembly concepts with an adaptable degree of automation are becoming increasingly important. Currently, charging stations are still manufactured manually. With increasing quantities, however, manual production is no longer economical. New technologies such as lightweight robotics offer a great potential for making production more flexible in terms of quantity. At the same time, new challenges arise because these requirements must be taken into account from the very beginning of product development and process planning. Currently, there are no planning approaches and recommendations for action that take this into consideration. Therefore, the research project “Simultaneous product and process development of a charging station outlet module suitable for automation” (SUPPLy) develops an integrated, digital and simultaneous product and process development of a modular charging station suitable for automation. The aim of the project is to develop an assembly process which enables an economic production of charging stations in case of fluctuating sales figures. The focus is not only on changes in the production process but also on a product design that is suitable for automation. The paper presents the ideas on a conceptual level.

Hossain, SI, Islam, MZ, Saha, SC & Deplazes, E 2022, 'Drug Meets Monolayer: Understanding the Interactions of Sterol Drugs with Models of the Lung Surfactant Monolayer Using Molecular Dynamics Simulations' in Methods in Molecular Biology, Springer US, Switzerland, pp. 103-121.
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The lung surfactant monolayer (LSM) is a thin layer of lipids and proteins that forms the air/water interface of the alveoli. The primary function of the LSM is to reduce the surface tension at the air/water interface during breathing. The LSM also forms the main biological barrier for any inhaled particles, including drugs, to treat lung diseases. Elucidating the mechanism by which these drugs bind to and absorb into the LSM requires a molecular-level understanding of any drug-induced changes to the morphology, structure, and phase changes of the LSM.Molecular dynamics simulations have been used extensively to study the structure and dynamics of the LSM. The monolayer is usually simulated in at least two states: the compressed state, mimicking exhalation, and the expanded state, mimicking inhalation. In this chapter, we provide detailed instructions on how to set up, run, and analyze coarse-grained MD simulations to study the concentration-dependent effect of a sterol drug on the LSM, both in the expanded and compressed state.

Adibi, T, Razavi, SE, Ahmed, SF, Amrikachi, A & Saha, SC 2022, 'Characteristic-Based Fluid Flow Modeling between Two Eccentric Cylinders in Laminar and Turbulent Regimes', Geofluids, vol. 2022, pp. 1-9.
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Determining the flow between eccentric cylinders is crucial in a wide range of industries. The governing equations for the flow between eccentric cylinders cannot be solved analytically. Therefore, three-dimensional incompressible viscous fluid flow between eccentric and concentric cylinders has numerically been simulated in this paper to investigate them using a characteristic-based approach. The first-order characteristic-based scheme is used to calculate convective terms, whereas the second-order averaging technique is used to calculate viscous fluxes. The Taylor number, eccentricity distance, Reynolds number, and radius ratio are considered the controlling parameters of fluid flow between the cylinders. The influence of flow between cylinders on flow patterns is presented in terms of velocity, pressure, and flow contours. It is found that at a constant Taylor number, the asymmetric centrifugal forces produce the Taylor vortices on the right of the internal rotating cylinder as the eccentric distance increases. When the eccentric distance increases, the magnitude of shear stress and its fluctuation on the cylinder wall, as well as the pressure on the cylinder wall, rise. The numerical results obtained were validated by comparing them to previously published experimental results, which showed a high level of agreement.

Adibi, T, Sojoudi, A & Saha, SC 2022, 'Modeling of thermal performance of a commercial alkaline electrolyzer supplied with various electrical currents', International Journal of Thermofluids, vol. 13, pp. 100126-100126.
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Hydrogen produced by solar and other clean energy sources is an essential alternative to fossil fuels. In this stuy, a commercial alkaline electrolyzer with different cell numbers and electrode areas are simulated for different pressure, temperature, thermal resistance, and electrical current. This alkaline electrolyzer is considered unsteady in simulations, and different parameters such as temperature are obtained in terms of time. The obtained results are compared with similar results in the literature, and good agreement is observed. Various characteristics of this alkaline electrolyzer as thermoneutral voltage, faraday efficiency and cell voltage are calculated and displayed. The outlet heat rate and generated heat rate are obtained as well. The pressure and the temperature in the simulations are between 1 and 100 bar and between 300 and 360 Kelvin respectively. The results show that the equilibrium temperature is reached 2–3 h after the time when the Alkaline electrolyzer starts to work.

Aljaafari, A, Fattah, IMR, Jahirul, MI, Gu, Y, Mahlia, TMI, Islam, MA & Islam, MS 2022, 'Biodiesel Emissions: A State-of-the-Art Review on Health and Environmental Impacts', Energies, vol. 15, no. 18, pp. 6854-6854.
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Biodiesel is an alternative source of fuel for various automotive applications. Because of the increasing demand for energy and the scarcity of fossil fuels, researchers have turned their attention to biodiesel production from various sources in recent years. The production of biofuels from organic materials and waste components allows for the use of these waste resources in transporting resources and people over long distances. As a result, developing sustainable measures for this aspect of life is critical, as knowledge of appropriate fuel sources, corresponding emissions, and health impacts will benefit the environment and public health assessment, which is currently lacking in the literature. This study investigates biodiesel’s composition and production process, in addition to biodiesel emissions and their associated health effects. Based on the existing literature, a detailed analysis of biodiesel production from vegetable oil crops and emissions was undertaken. This study also considered vegetable oil sources, such as food crops, which can have a substantial impact on the environment if suitable growing procedures are not followed. Incorporating biodegradable fuels as renewable and sustainable solutions decreases pollution to the environment. The effects of biodiesel exhaust gas and particulates on human health were also examined. According to epidemiologic studies, those who have been exposed to diesel exhaust have a 1.2–1.5 times higher risk of developing lung cancer than those who have not. In addition, for every 24 parts per billion increase in NO2 concentration, symptom prevalence increases 2.7-fold. Research also suggests that plain biodiesel combustion emissions are more damaging than petroleum diesel fuel combustion emissions. A comprehensive analysis of biodiesel production, emissions, and health implications would advance this field’s understanding.

Al-zqebah, R, Hoffmann, F, Bennett, N, Deuse, J & Clemon, L 2022, 'Layout optimisation for production systems in the wool industry using discrete event simulation', Journal of Industrial Engineering and Management, vol. 15, no. 2, pp. 296-296.
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Purpose: Computer-aided production engineering simulation is a common approach in the search for improvements to real systems. They are used in various industrial sectors and are a basis for optimization. Such production simulations have found limited use in the wool industry. This study aims to compare the performance of different woolshed layouts (curved vs linear).  Design/methodology/approach: A discrete event simulation is constructed for both considered layouts in Siemens Technomatix Plant Simulation software. Data from an in-field observational visit to a working woolshed is used to validate the simulation model. The different layouts are compared in their base configuration and with equipment and worker changes to evaluate the impacts on throughput.Findings: In the base configurations, the curved layout reduces some worker travel time which increases production by 11 fleeces per day over the linear layout. The addition of an extra skirting table in the curved layout further increases throughout by 30 fleeces per day. The addition of more wool handlers does not have as large of an impact indicating that processing limits occur due to equipment capacity and shearer speed.Practical implications: This verifies the proposed curved shed layout improves production and gives farmers the ability to compute the long-term economic impact. The results also highlight that other processing stages in the shed need adjustment for more system gains.Originality/value: This is the first application of discrete event simulation to evaluate woolsheds operations and introduce multiple improvement scenarios.

Arakawa, K, Kono, N, Malay, AD, Tateishi, A, Ifuku, N, Masunaga, H, Sato, R, Tsuchiya, K, Ohtoshi, R, Pedrazzoli, D, Shinohara, A, Ito, Y, Nakamura, H, Tanikawa, A, Suzuki, Y, Ichikawa, T, Fujita, S, Fujiwara, M, Tomita, M, Blamires, SJ, Chuah, J-A, Craig, H, Foong, CP, Greco, G, Guan, J, Holland, C, Kaplan, DL, Sudesh, K, Mandal, BB, Norma-Rashid, Y, Oktaviani, NA, Preda, RC, Pugno, NM, Rajkhowa, R, Wang, X, Yazawa, K, Zheng, Z & Numata, K 2022, '1000 spider silkomes: Linking sequences to silk physical properties', Science Advances, vol. 8, no. 41.
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Spider silks are among the toughest known materials and thus provide models for renewable, biodegradable, and sustainable biopolymers. However, the entirety of their diversity still remains elusive, and silks that exceed the performance limits of industrial fibers are constantly being found. We obtained transcriptome assemblies from 1098 species of spiders to comprehensively catalog silk gene sequences and measured the mechanical, thermal, structural, and hydration properties of the dragline silks of 446 species. The combination of these silk protein genotype-phenotype data revealed essential contributions of multicomponent structures with major ampullate spidroin 1 to 3 paralogs in high-performance dragline silks and numerous amino acid motifs contributing to each of the measured properties. We hope that our global sampling, comprehensive testing, integrated analysis, and open data will provide a solid starting point for future biomaterial designs.

Arsalanloo, A, Abbasalizadeh, M, Khalilian, M, Saniee, Y, Ramezanpour, A & Islam, MS 2022, 'A computational approach to understand the breathing dynamics and pharmaceutical aerosol transport in a realistic airways', Advanced Powder Technology, vol. 33, no. 7, pp. 103635-103635.
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Bem, NFSD, Ruppert, MG, Fleming, AJ & Yong, YK 2022, 'Simultaneous tip force and displacement sensing for AFM cantilevers with on-chip actuation: Design and characterization for off-resonance tapping mode', Sensors and Actuators A: Physical, vol. 338, pp. 113496-113496.
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The use of integrated on-chip actuation simplifies the identification of a cantilever resonance, can improve imaging speed, and enables the use of smaller cantilevers, which is required for low-force imaging at high speed. This article describes a cantilever with on-chip actuation and novel dual-sensing capabilities for AFM. The dual-sensing configuration allows for tip displacement and tip force to be measured simultaneously. A mathematical model is developed and validated with finite element analysis. A physical prototype is presented, and its calibration and validation are presented. The cantilever is optimized for use in off-resonance tapping modes. Experimental results demonstrate an agreement between the on-chip sensors and external force and displacement measurements.

Beni, HM, Mortazavi, H & Islam, MS 2022, 'Biomedical and biophysical limits to mathematical modeling of pulmonary system mechanics: a scoping review on aerosol and drug delivery', Biomechanics and Modeling in Mechanobiology, vol. 21, no. 1, pp. 79-87.
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Bhowmick, S, Xu, F, Molla, MM & Saha, SC 2022, 'Chaotic phenomena of natural convection for water in a V-shaped enclosure', International Journal of Thermal Sciences, vol. 176, pp. 107526-107526.
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Blamires, SJ, Nobbs, M, Wolff, JO & Heu, C 2022, 'Nutritionally induced nanoscale variations in spider silk structural and mechanical properties', Journal of the Mechanical Behavior of Biomedical Materials, vol. 125, pp. 104873-104873.
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Brown, M, Dey, S, Tuxworth, G, Bernus, P & de Souza, P 2022, 'Dynamic verification of satellite systems using Ilities', Journal of Space Safety Engineering, vol. 9, no. 2, pp. 257-262.
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Burden, AG, Caldwell, GA & Guertler, MR 2022, 'Towards human–robot collaboration in construction: current cobot trends and forecasts', Construction Robotics, vol. 6, no. 3-4, pp. 209-220.
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Collaborative robots, or cobots, provide opportunities for their use in a range of complex scenarios in different industries,including construction. As a variant of industrial robots commonly used in automation, cobots incorporate inbuilt safetymeasures, lower costs, and easier operator programming. This article questions the state of recent peer-reviewed researchregarding the uptake and implementation of collaborative robotics in the construction industry. A ‘horizon scanning’ reviewof literature is presented in this article to uncover recent trends and forecasts in cobotics research specific to the constructionindustry. The horizon scan targets examples of human–robot collaboration (HRC) and other human–robot interactions (HRI)focussed on construction tasks. By examining where HRC has been applied in construction, we identify which drivers, ena-blers, and barriers that influence the future of construction cobots. Human-readable task models coupled with vision systems,such as augmented reality or haptic feedback and wearable interaction devices are strong enablers in how HRC can be betteradopted. Most existing research into producing diversity in robot interaction methods for HRC prescribes to overcomingstatic approaches, which is well suited to answering the ever-changing nature of construction sites. On the other hand, thedynamic nature of construction sites and worker perceptions impact the uptake of new technologies in industry where cobotsare often mistaken for highly automated industrial arms. Based on these findings, the need to build trust through successfuluse cases and case studies that demonstrate successful outcomes and productivity evaluations are necessary to overcome thebarriers to cobot adoption in the construction industry.

Bykerk, L & Valls Miro, J 2022, 'Detection of Water Leaks in Suburban Distribution Mains with Lift and Shift Vibro-Acoustic Sensors', Vibration, vol. 5, no. 2, pp. 370-382.
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Leaks in Water Distribution Networks (WDNs) account for a large proportion of Non-Revenue Water (NRW) for utilities worldwide. Typically, a leak is only confirmed once water surfaces, allowing the leak to be traced; however, a high percentage of leaks may never surface, incurring large water losses and costs for utilities. Active Leak Detection (ALD) methods can be used to detect hidden leaks; however, the success of such methods is highly dependent on the available detection instrumentation and the experience of the operator. To aid in the detection of both hidden and surfacing leaks, deployment of vibro-acoustic sensors is being increasingly explored by water utilities for temporary structural health monitoring. In this paper, data were collected and curated from a range of temporary Lift and Shift (L&S) vibro-acoustic sensor deployments across suburban Sydney. Time-frequency and frequency-domain features were generated to assess the performance and suitability of two state-of-the-art binary classification models for water leak detection. The results drawn from the extensive field data sets are shown to provide reliable leak detection outcomes, with accuracies of at least 97% and low false positive rates. Through the use of such a reliable leak detection system, utilities can streamline their leak detection and repair processes, effectively mitigating NRW and reducing customer disruptions.

Bykerk, L & Valls Miro, J 2022, 'Vibro-Acoustic Distributed Sensing for Large-Scale Data-Driven Leak Detection on Urban Distribution Mains', Sensors, vol. 22, no. 18, pp. 6897-6897.
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Non-surfacing leaks constitute the dominant source of water losses for utilities worldwide. This paper presents advanced data-driven analysis methods for leak monitoring using commercial field-deployable semi-permanent vibro-acoustic sensors, evaluated on live data collected from extensive multi-sensor deployments across a sprawling metropolitan city. This necessarily includes a wide variety of pipeline sizes, materials and surrounding soils, as well as leak sources and rates brought about by external factors. The novel proposition for structural pipe health monitoring shows that excellent leak/no-leak classification results (>94% accuracy) can be observed using Convolutional Neural Networks (CNNs) trained with Short-Time Fourier Transforms (STFTs) of the raw audio files. Most notably, it is shown how this can be achieved irrespective of the sensor used, with four models from different manufactures being part of the investigation, and over time across extended densely populated areas.

Chandra Adhikari, S, Kumar Chanda, R, Bhowmick, S, Nath Mondal, R & Chandra Saha, S 2022, 'Pressure-Induced Instability Characteristics of a Transient Flow and Energy Distribution through a Loosely Bent Square Duct', Energy Engineering, vol. 119, no. 1, pp. 429-451.
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Chen, C, Ding, L, Liu, B, Du, Z, Liu, Y, Di, X, Shan, X, Lin, C, Zhang, M, Xu, X, Zhong, X, Wang, J, Chang, L, Halkon, B, Chen, X, Cheng, F & Wang, F 2022, 'Exploiting Dynamic Nonlinearity in Upconversion Nanoparticles for Super-Resolution Imaging', Nano Letters, vol. 22, no. 17, pp. 7136-7143.
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Single-beam super-resolution microscopy, also known as superlinear microscopy, exploits the nonlinear response of fluorescent probes in confocal microscopy. The technique requires no complex purpose-built system, light field modulation, or beam shaping. Here, we present a strategy to enhance this technique's spatial resolution by modulating excitation intensity during image acquisition. This modulation induces dynamic optical nonlinearity in upconversion nanoparticles (UCNPs), resulting in variations of nonlinear fluorescence response in the obtained images. The higher orders of fluorescence response can be extracted with a proposed weighted finite difference imaging algorithm from raw fluorescence images to generate an image with higher resolution than superlinear microscopy images. We apply this approach to resolve single nanoparticles in a large area, improving the resolution to 132 nm. This work suggests a new scope for the development of dynamic nonlinear fluorescent probes in super-resolution nanoscopy.

Chen, Y, Zhao, L, Zhang, Y, Huang, S & Dissanayake, G 2022, 'Anchor Selection for SLAM Based on Graph Topology and Submodular Optimization', IEEE Transactions on Robotics, vol. 38, no. 1, pp. 329-350.
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This article considers simultaneous localization and mapping (SLAM) problem for robots in situations where accurate estimates for some of the robot poses, termed anchors, are available. These may be acquired through external means, for example, by either stopping the robot at some previously known locations or pausing for a sufficient period of time to measure the robot poses with an external measurement system. The main contribution is an efficient algorithm for selecting a fixed number of anchors from a set of potential poses that minimizes estimated error in the SLAM solution. Based on a graph-topological connection between the D-optimality design metric and the tree-connectivity of the pose-graph, the anchor selection problem can be formulated approximately as a submatrix selection problem for reduced weighted Laplacian matrix, leading to a cardinality-constrained submodular maximization problem. Two greedy methods are presented to solve this submodular optimization problem with a performance guarantee. These methods are complemented by Cholesky decomposition, approximate minimum degree permutation, order reuse, and rank-1 update that exploit the sparseness of the weighted Laplacian matrix. We demonstrate the efficiency and effectiveness of the proposed techniques on public-domain datasets, Gazebo simulations, and real-world experiments.

Chu, Y, Zhao, S, He, L & Niu, F 2022, 'Wind noise suppression in filtered-x least mean squares-based active noise control systems', The Journal of the Acoustical Society of America, vol. 152, no. 6, pp. 3340-3345.
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Wind noise is notorious for its detrimental impacts on audio devices. This letter evaluates the influence of wind noise on the active noise control performance of headphones in a wind tunnel, and the noise reduction is found to decrease with wind speeds. To improve the performance of noise control systems in windy environments, the filtered-x least mean squares algorithm is modified based on the total least squares technique, taking the characteristics of wind noise into account. Computer simulations with real-recorded data demonstrate that the proposed algorithm could improve the noise reduction by approximately 3 dB in windy conditions.

Clemon, LM 2022, 'Rapid estimation of viral emission source location via genetic algorithm', Computational Mechanics, vol. 69, no. 5, pp. 1213-1224.
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AbstractIndoor spread of infectious diseases is well-studied as a common transmission route. For highly infectious diseases, like Sars-CoV-2, considering poorly or semi ventilated areas outdoors is increasingly important. This is important in communities with high proportions of infected people, highly infectious variants, or where spread is difficult to manage. This work develops a simulation framework based on probabilistic distributions of viral particles, decay, and infection. The methodology reduces the computational cost of generating rapid estimations of a wide variety of scenarios compared to other simulation methods with high computational cost and more fidelity. Outdoor predictions are provided in example applications for a gathering of five people with oscillating wind and a public speaking event. The results indicate that infection is sensitive to population density and outdoor transmission is plausible and likely locations of a virtual super-spreader are identified. Outdoor gatherings should consider precautions to reduce infection spread.

Cui, H, Wang, W, Xu, F, Saha, S & Liu, Q 2022, 'Transitional free convection flow and heat transfer within attics in cold climate', Thermal Science, vol. 26, no. 6 Part A, pp. 4699-4709.
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The transitional free convection flow and heat transfer within attics in cold climate are investigated using 3-D numerical simulations for a range of Rayleigh numbers from 103 to 106 and height-length ratios from 0.1 to 1.5. The development process of free convection in the attic could be classified into three-stages: an initial stage, a transitional stage, and a fully developed stage. Flow structures in different stages including transverse and longitudinal rolls are critically analyzed in terms of the location and strength of convection rolls and their impacts on the heat transfer. The transition unsteady flow and asymmetry flow in the fully developed stage is discussed for the fixed height-length ratio 0.5. Various flow regimes are given in a bifurcation diagram in the parameter space of Rayleigh numbers (102 < Ra < 107) for height-length ratios (0.1 < A < 1.5). The time series of heat transfer rate through the bottom wall is quantified for different height-length ratios. The overall heat transfer rate for the low Prandtl fluid (Pr = 0.7) could be enhanced based on 3-D flow structure.

Dai, P, Hassan, M, Sun, X, Zhang, M, Bian, Z & Liu, D 2022, 'A framework for multi-robot coverage analysis of large and complex structures', Journal of Intelligent Manufacturing, vol. 33, no. 5, pp. 1545-1560.
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Darwish, A, Halkon, B & Oberst, S 2022, 'Non-Contact Vibro-Acoustic Object Recognition Using Laser Doppler Vibrometry and Convolutional Neural Networks', Sensors, vol. 22, no. 23, pp. 9360-9360.
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Laser Doppler vibrometers (LDVs) have been widely adopted due to their large number of benefits in comparison to traditional contacting vibration transducers. Their high sensitivity, among other unique characteristics, has also led to their use as optical microphones, where the measurement of object vibration in the vicinity of a sound source can act as a microphone. Recent work enabling full correction of LDV measurement in the presence of sensor head vibration unlocks new potential applications, including integration within autonomous vehicles (AVs). In this paper, the common AV challenge of object classification is addressed by presenting and evaluating a novel, non-contact vibro-acoustic object recognition technique. This technique utilises a custom set-up involving a synchronised loudspeaker and scanning LDV to simultaneously remotely solicit and record responses to a periodic chirp excitation in various objects. The 864 recorded signals per object were pre-processed into spectrograms of various forms, which were used to train a ResNet-18 neural network via transfer learning to accurately recognise the objects based only on their vibro-acoustic characteristics. A five-fold cross-validation optimisation approach is described, through which the effects of data set size and pre-processing type on classification accuracy are assessed. A further assessment of the ability of the CNN to classify never-before-seen objects belonging to groups of similar objects on which it has been trained is then described. In both scenarios, the CNN was able to obtain excellent classification accuracy of over 99.7%. The work described here demonstrates the significant promise of such an approach as a viable non-contact object recognition technique suitable for various machine automation tasks, for example, defect detection in production lines or even loose rock identification in underground mines.

Darwish, A, Halkon, B, Rothberg, S, Oberst, S & Fitch, R 2022, 'A comparison of time and frequency domain-based approaches to laser Doppler vibrometer instrument vibration correction', Journal of Sound and Vibration, vol. 520, pp. 116607-116607.
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Deuse, J, West, N & Syberg, M 2022, 'Rediscovering scientific management. The evolution from industrial engineering to industrial data science', International Journal of Production Management and Engineering, vol. 10, no. 1, pp. 1-12.
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Industrial Engineering, through its role as design, planning and organizational body of the industrial production, has been crucial for the success of manufacturing companies for decades. The potential, expected over the course of Industry 4.0 and through the application of Data Analytic tools and methods, requires a coupling to established methods. This creates the necessity to extend the traditional job description of Industrial Engineering by new tools from the field of Data Analytics, namely Industrial Data Science. Originating from the historic pioneers of Industrial Engineering, it is evident that the basic principles will remain valuable. However, further development in view of the data analytic possibilities is already taking place. This paper reviews the origins of Industrial Engineering with reference to four pioneers, draws a connection to current day usage, and considers possibilities for future applications of Industrial Data Science.

Ding, L, Shan, X, Wang, D, Liu, B, Du, Z, Di, X, Chen, C, Maddahfar, M, Zhang, L, Shi, Y, Reece, P, Halkon, B, Aharonovich, I, Xu, X & Wang, F 2022, 'Lanthanide Ion Resonance‐Driven Rayleigh Scattering of Nanoparticles for Dual‐Modality Interferometric Scattering Microscopy', Advanced Science, vol. 9, no. 32, pp. e2203354-2203354.
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AbstractLight scattering from nanoparticles is significant in nanoscale imaging, photon confinement. and biosensing. However, engineering the scattering spectrum, traditionally by modifying the geometric feature of particles, requires synthesis and fabrication with nanometre accuracy. Here it is reported that doping lanthanide ions can engineer the scattering properties of low‐refractive‐index nanoparticles. When the excitation wavelength matches the ion resonance frequency of lanthanide ions, the polarizability and the resulted scattering cross‐section of nanoparticles are dramatically enhanced. It is demonstrated that these purposely engineered nanoparticles can be used for interferometric scattering (iSCAT) microscopy. Conceptually, a dual‐modality iSCAT microscopy is further developed to identify different nanoparticle types in living HeLa cells. The work provides insight into engineering the scattering features by doping elements in nanomaterials, further inspiring exploration of the geometry‐independent scattering modulation strategy.

Ding, L, Shan, X, Wang, D, Liu, B, Du, Z, Di, X, Chen, C, Maddahfar, M, Zhang, L, Shi, Y, Reece, P, Halkon, B, Aharonovich, I, Xu, X & Wang, F 2022, 'Lanthanide Ion Resonance‐Driven Rayleigh Scattering of Nanoparticles for Dual‐Modality Interferometric Scattering Microscopy (Adv. Sci. 32/2022)', Advanced Science, vol. 9, no. 32.
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Eager, D, Ishac, K, Zhou, S & Hossain, I 2022, 'Investigating the Knuckleball Effect in Soccer Using a Smart Ball and Training Machine', Sensors, vol. 22, no. 11, pp. 3984-3984.
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The term knuckleball in sporting jargon is used to describe a ball that has been launched with minimal spin, resulting in a trajectory that is erratic and unpredictable. This phenomenon was first observed in baseball (where the term originated) and has since been observed in other sports. While knuckleball has long fascinated the scientific community, the bulk of research has primarily focused on knuckleball as it occurs in baseball. Following the changes in the design of the soccer ball after the 2006 World Cup, knuckleball and ball aerodynamics were exploited by soccer players. This research examined the properties of a knuckleball in the sport of soccer. We designed and evaluated a system that could reproduce the knuckleball effect on soccer balls based on previous theories and characteristics outlined in our literature review. Our system is comprised of the Adidas miCoach Smart Ball, a companion smart phone app for data collection, a ball-launching machine with programmable functions, and a video-based tracking system and Tracker motion analysis software. The results from the testing showed that our system was successfully able to produce knuckleball behaviour on the football in a highly consistent manner. This verified the dynamic models of knuckleball that we outline. While a small portion of the data showed some lateral deviations (zig-zag trajectory), this erratic and unpredictable trajectory was much smaller in magnitude when compared to examples seen in professional games. The sensor data from the miCoach app and trajectory data from the Tracker motion analysis software, showed that the knuckleballs were consistently reproduced in-line with theoretical dynamics.

Eager, D, Zhou, S, Hossain, I, Ishac, K & Halkon, B 2022, 'Research on Impact Attenuation Characteristics of Greyhound Racing Track Padding for Injury Prevention', Vibration, vol. 5, no. 3, pp. 497-512.
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To reduce injuries to greyhounds caused by collisions with fixed racing track objects such as the outside fence or the catching pen structures, padding systems are widely adopted. However, there are currently neither recognised standards nor minimum performance thresholds for greyhound industry padding systems. This research is the first of its kind to investigate the impact attenuation characteristics of different padding systems for use within the greyhound racing industry for the enhanced safety and welfare of racing greyhounds. A standard head injury criterion (HIC) meter was used to examine padding impact attenuation performance based on the maximum g-force, HIC level and the HIC duration. Initially, greyhound racing speed was recorded and analysed with the IsoLynx system to understand the potential impact hazard to greyhounds during racing which indicates the necessity for injury prevention with padding. A laboratory test was subsequently conducted to compare the impact attenuation performance of different kinds of padding. Since padding impact attenuation characteristics are also affected by the installation and substrate, onsite testing was conducted to obtain the padding system impact attenuation performance in actual greyhound racing track applications. The test results confirm that the padding currently used within the greyhound industry is adequate for the fence but inadequate when used for rigid structural members such as the catching pen gate supports. Thus, increasing the padding thickness is strongly recommended if it is used at such locations. More importantly, it is also recommended that, after the installation of padding on the track, its impact attenuation characteristics be tested according to the methodology developed herein to verify the suitability for protecting greyhounds from injury.

Eager, D, Zhou, S, Ishac, K, Hossain, I, Richards, A & Sharwood, LN 2022, 'Investigation into the Trampoline Dynamic Characteristics and Analysis of Double Bounce Vibrations', Sensors, vol. 22, no. 8, pp. 2916-2916.
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Double bounce is an unusual and potentially very hazardous phenomenon that most trampoline users may have experienced, yet few would have really understood how and why it occurs. This paper provides an in-depth investigation into the double bounce. Firstly, the static and dynamic characteristics of a recreational trampoline are analysed theoretically and verified through experiments. Then, based on the developed trampoline dynamic model, double bounce simulation is conducted with two medicine balls released with different time delays. Through simulation, the process of double bounce is presented in detail, which comprehensively reveals how energy is transferred between users during double bounce. Furthermore, the effect of release time delay on double bounce is also presented. Finally, we conducted an experiment which produced similar results to the simulation and validated the reliability of the trampoline dynamic model and double bounce theoretical analysis.

Fan, Y, Liu, D & Ye, L 2022, 'A Novel Continuum Robot With Stiffness Variation Capability Using Layer Jamming: Design, Modeling, and Validation', IEEE Access, vol. 10, pp. 130253-130263.
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This paper presents a novel continuum robot (OctRobot-I) that has controllable stiffness variation capability in both the transverse and axial directions. Robot design, stiffness variation analysis and experimental testing are discussed in detail. Stiffness models based on the Euler-Bernoulli beam theory are developed, and then four static deflection cases are analysed. Experiments are conducted with two types of layer jamming sheaths (overlap numbers n =3, 5) and four different vacuum pressures (0kPa, 25kPa, 50kPa, 75kPa) at three different bending angles (0°, 90°, 180°). The results demonstrate that the stiffness changing tendency is in compliance with the derived models and show that the robot has a good stiffness variable capability. With the jamming sheath of n =3, the stiffness ranges (ratios) are 36.4 to 241.7 N/m (6.6) and 92.9 to 19.3×103 N/m (207.8) in the transverse and axial directions, respectively. With the jamming sheath of n =5, the stiffness ranges (ratios) are 65.7 to 398.3 N/m (6.1) and 106.7 to 20.8×103 N/m (194.9) in the transverse and axial directions, respectively. Additionally, the actuating and gripping experiments demonstrate that this robot has good performance in real-world applications.

Feng, K, Ji, JC, Li, Y, Ni, Q, Wu, H & Zheng, J 2022, 'A novel cyclic-correntropy based indicator for gear wear monitoring', Tribology International, vol. 171, pp. 107528-107528.
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Gearbox is a vulnerable component of a turbine's drivetrain and plays a vital role in the power transmission in wind turbines. Wind turbines usually operate under harsh working environments, such as in deserts, oceans, and on hills. The adverse operating conditions (such as inevitable fluctuating wind loads and speeds) make the gearbox transmission prone to reliability degradation and premature failure. Gear wear is a common and unavoidable surface degradation phenomenon during the lifespan of the gear transmission system. The gear wear propagation can result in severe failures, such as gear surface spalling, gear root crack, and gear tooth breakage, all of which could lead to the failure of the drivetrain system of wind turbines and bring unexpected economic loss, even serious accidents. Thus, it is crucial to monitor the gear wear propagation progression in order to enable reliable and safe operation. To this end, this paper develops a novel vibration-based health indicator to monitor the gear surface degradation induced by gear wear progression. With the help of the novel indicator developed, the health status of the gearbox can be well evaluated and thus predictive maintenance-based decisions can be made to reduce maintenance costs and minimize gearbox failures in wind turbines. A series of endurance tests under different lubrication conditions and operational conditions are carried out to verify the effectiveness of the gear wear monitoring indicator.

Feng, K, Ji, JC, Wang, K, Wei, D, Zhou, C & Ni, Q 2022, 'A novel order spectrum-based Vold-Kalman filter bandwidth selection scheme for fault diagnosis of gearbox in offshore wind turbines', Ocean Engineering, vol. 266, pp. 112920-112920.
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Vold-Kalman order tracking filter is an effective technique for dealing with non-stationary vibrations which offshore wind turbines often encounter. It has a unique capability to extract and track the time waveforms of harmonics in short transients without phase bias, and this capability is beneficial to the condition monitoring of offshore wind turbines. In general, the accuracy of the tracking results of the Vold-Kalman filer for condition monitoring is heavily dependent on the selection of filter bandwidth. A fixed filter bandwidth becomes problematic when processing different types of signals under varying operating conditions. Significant errors may arise in the tracking, rendering the condition monitoring of offshore wind turbines unreliable. To address this issue, this paper proposes a novel scheme for Vold-Kalman filter bandwidth selection to guarantee the consistency and accuracy of the offshore wind turbine condition monitoring process, ensuring reliable fault diagnosis. A numerical model is used to evaluate the effectiveness of the proposed bandwidth selection scheme first. Then the proposed scheme is further validated through the offshore wind turbine planetary gearbox datasets, together with the demonstration of the fault diagnosis capability of the filtered results.

Feng, K, Ni, Q, Beer, M, Du, H & Li, C 2022, 'A novel similarity-based status characterization methodology for gear surface wear propagation monitoring', Tribology International, vol. 174, pp. 107765-107765.
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The gearbox is a vital component for rotating machinery and has been used in many critical engineering applications. Surface wear is a common but inevitable phenomenon during the lifespan of the gearbox. Its propagation can result in some catastrophic failures and cause unexpected economic loss. Therefore, it is vital to evaluate the degradation process of the gear system caused by surface wear propagation in order to make reliable predictive maintenance-based decisions to ensure the safe operation of the gearbox transmission system. The vibration analysis technique is a prevailing tool for rotating machine condition monitoring. However, research on vibration-based gear wear monitoring is relatively rare as the dynamic interactions between gear surface wear and gear system dynamic characteristics would produce complex gear dynamic responses and vibration features. Therefore, this paper presents a novel similarity-based status characterization methodology for gear wear monitoring. In this proposed methodology, a novel gear wear monitoring indicator is developed to evaluate gear tooth contact characteristics at different wear severities, which could significantly benefit gear systems' health management. The effectiveness of the proposed method for gear wear propagation process monitoring is presented and proven through a series of run-to-failure tests with different lubrications and operational conditions.

Francis, I & Saha, S 2022, 'Surface tension effects on flow dynamics and alveolar mechanics in the acinar region of human lung'.
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Computational fluid dynamics (CFD) simulations, in-vitro setups, andexperimental ex-vivo approaches have been applied to numerous alveolargeometries over the past years. They aimed to study and examine airflowpatterns, particle transport, and particle-alveolar wall deposition fractions.These studies are imperative to both pharmaceutical and toxicological studies,especially nowadays with the escalation of the menacing COVID-19 virus.However, most of these studies ignored the surfactant layer that covers thealveoli and the effect of the air-surfactant surface tension on flow dynamicsand air-alveolar surface mechanics. The present study employs a realistic humanbreathing profile of 4.75 to emphasize the importance of the surfactant layerby numerically comparing airflow phenomena between a surfactant-enriched andsurfactant-deficient model. The acinar model exhibits physiologically accuratealveolar and duct dimensions extending from lung generations 18 to 23. Proximallung generations experience dominant recirculating flow while farthergenerations in the distal alveolar region exhibit dominant radial flows. In thesurfactant-enriched model, surface tension values alternate during inhalationand exhalation. In the surfactant-deficient model, only water coats thealveolar walls. Results showed that surfactant deficiency in the alveoliadversely alters airflow behavior and generates unsteady chaotic breathingthrough the production of vorticities, accompanied by higher vorticity andvelocity magnitudes. In addition, high air-water surface tension in thesurfactant-deficient case was found to induce higher shear stress values on thealveolar walls than that of the surfactant-enriched case. Overall, it wasconcluded that the presence of the surfactant improves respiratory mechanicsand allows for smooth breathing and normal respiration.

Francis, I & Saha, SC 2022, 'Computational fluid dynamics and machine learning algorithms analysis of striking particle velocity magnitude, particle diameter, and impact time inside an acinar region of the human lung', Physics of Fluids, vol. 34, no. 10, pp. 101904-101904.
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Complementing computational fluid dynamics (CFD) simulations with machine learning algorithms is becoming increasingly popular as the combination reduces the computational time of the CFD simulations required for classifying, predicting, or optimizing the impact of geometrical and physical variables of a specific study. The main target of drug delivery studies is indicating the optimum particle diameter for targeting particular locations in the lung to achieve a desired therapeutic effect. In addition, the main goal of molecular dynamics studies is to investigate particle–lung interaction through given particle properties. Therefore, this study combines the two by numerically determining the optimum particle diameter required to obtain an ideal striking velocity magnitude (velocity at the time of striking the alveoli, i.e., deposition by sedimentation/diffusion) and impact time (time from release until deposition) inside an acinar part of the lung. At first, the striking velocity magnitudes and time for impact (two independent properties) of three different particle diameters (0.5, 1.5, and 5 μm) are computed using CFD simulations. Then, machine learning classifiers determine the particle diameter corresponding to these two independent properties. In this study, two cases are compared: A healthy acinus where a surfactant layer covers the inner surface of the alveoli providing low air–liquid surface tension values (10 mN/m), and a diseased acinus where only a water layer covers the surface causing high surface tension values (70 mN/m). In this study, the airflow velocity throughout the breathing cycle corresponds to a person with a respiratory rate of 13 breaths per minute and a volume flow rate of 6 l/min. Accurate machine learning results showed that all three particle diameters attain larger velocities and smaller impact times in a diseased acinus compared to a healthy one. In both cases, the 0.5-μm particles acquire the smallest velocities an...

Francis, I & Saha, SC 2022, 'Surface tension effects on flow dynamics and alveolar mechanics in the acinar region of human lung', Heliyon, vol. 8, no. 10, pp. e11026-e11026.
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Francis, I, Shrestha, J, Paudel, KR, Hansbro, PM, Warkiani, ME & Saha, SC 2022, 'Recent advances in lung-on-a-chip models', Drug Discovery Today, vol. 27, no. 9, pp. 2593-2602.
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Gunatilake, A, Kodagoda, S & Thiyagarajan, K 2022, 'A Novel UHF-RFID Dual Antenna Signals Combined With Gaussian Process and Particle Filter for In-Pipe Robot Localization', IEEE Robotics and Automation Letters, vol. 7, no. 3, pp. 6005-6011.
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Condition assessment of underground infrastructures such as pipe networks is crucial for aging cities around the globe. The development of robotic technologies over the years led to the application of them in the condition assessment of pipe networks. However, there is a gap for accurate localization technology due to the complexity of the environment. In this letter, we propose a novel ultra-high frequency radio frequency identification (UHF-RFID) technology dual antenna system combined with Gaussian process and Particle filter algorithms to achieve millimetre level localization accuracy. The system is capable of achieving millimetre level accuracy over 50m of length without an apparent estimation drift. The results were validated through experiments conducted using an extracted water pipe section.

Gunatilake, A, Kodagoda, S & Thiyagarajan, K 2022, 'Battery-Free UHF-RFID Sensors-Based SLAM for In-Pipe Robot Perception', IEEE Sensors Journal, vol. 22, no. 20, pp. 20019-20026.
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Hamidi, BA, Hosseini, SA & Hayati, H 2022, 'Forced torsional vibration of nanobeam via nonlocal strain gradient theory and surface energy effects under moving harmonic torque', Waves in Random and Complex Media, vol. 32, no. 1, pp. 318-333.
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Hamidi, BA, Hosseini, SA, Hayati, H & Hassannejad, R 2022, 'Forced axial vibration of micro and nanobeam under axial harmonic moving and constant distributed forces via nonlocal strain gradient theory', Mechanics Based Design of Structures and Machines, vol. 50, no. 5, pp. 1491-1505.
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Haris, A, Sepehrirahnama, S, Lee, HP & Lim, K-M 2022, 'Mitigation of vibration of ship structure via local structural modifications', Ships and Offshore Structures, vol. 17, no. 8, pp. 1684-1694.
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He, Z, Luo, Q, Li, Q, Zheng, G & Sun, G 2022, 'Fatigue behavior of CFRP/Al adhesive joints — Failure mechanisms study using digital image correlation (DIC) technique', Thin-Walled Structures, vol. 174, pp. 109075-109075.
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Henke, T & Deuse, J 2022, 'Application of heuristics for packing problems to optimise throughput time in fixed position assembly islands', International Journal of Productivity and Quality Management, vol. 36, no. 1, pp. 150-150.
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Henneken, J, Blamires, SJ, Goodger, JQD, Jones, TM & Elgar, MA 2022, 'Population level variation in silk chemistry but not web architecture in a widely distributed orb web spider', Biological Journal of the Linnean Society, vol. 137, no. 2, pp. 350-358.
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Abstract Spider webs are iconic examples of extended phenotypes that are remarkably plastic across different environments. Orb webs are not only effective traps for capturing prey, but can also provide information to potential mates and, in some cases, potential predators and prey through silk-based chemicals. As with regular phenotypic traits, variability in the properties of spider webs is thought to be mediated by a combination of genetic and environmental effects. Here, we examined variation in several key features of the webs of the orb-weaving spider Argiope keyserlingi across five geographically disparate populations. We documented variation in web architecture and chemical properties of webs collected directly from the field. We then probed the potential for the underlying environmental driver of local insect abundance to explain this variation, by analysing the properties of orb webs constructed by the spiders from these different populations, but under identical laboratory conditions. We found no evidence of variation across populations in the architecture of webs constructed in the laboratory, despite the large geographic distances. Nonetheless, we discovered between population variation in the composition of chemicals found on the surface of silk and in the taxonomic distribution of available prey. Furthermore, there was a positive correlation between the quantity of nitrogenous compounds in web silks and female body condition. When combined, these findings suggest that environmental mechanisms can drive variation in web traits across spider populations.

Huang, S & Zhao, L 2022, '2021 IEEE RAS Winter School on Simultaneous Localization and Mapping in Deformable Environments [Education]', IEEE Robotics & Automation Magazine, vol. 29, no. 1, pp. 120-122.
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Simultaneous localization and mapping (SLAM) is an important research problem for robot navigation in unknown environments, particularly when GPS is not available. SLAM requires a robot to be able to build a map of the environment in real time and simultaneously estimate its own location within the map. In the past two decades, significant progress has been made in the research for SLAM in static environments. However, when an environment has deformations, such as when a surgical robot is navigating in internal body environments, SLAM needs to build a time-varying 3D map of the soft tissues and estimate the location of the robot/sensor within the map. This poses a challenging problem since the robot/sensor is moving while the environment is deforming.

Huang, X, Clemon, LM, Islam, MS & C. Saha, S 2022, 'Optimization of fluid characteristics in the main nozzle of an air-jet loom', Textile Research Journal, vol. 92, no. 3-4, pp. 525-538.
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As part of the propulsion system, the fluid dynamic features of the main nozzle can immediately affect the stability and efficiency of an air-jet loom. This study aims to optimize the fluid characteristics in the main nozzle of an air-jet loom. To investigate ways of weakening the effect of airflow congestion and backflow phenomenon occurring in the sudden expansion region, the computational fluid dynamics method is employed. Three-dimensional turbulence flow models for a regular main nozzle and 12 prototypes with different nozzle core tip geometry are built, simulated, and analyzed to get the optimum performance. Furthermore, a set of modified equations that consider the direction of airflow are proposed for better estimation of the friction force applied by the nozzle. The result shows that the nozzle core tip's geometry has a significant influence on the internal airflow, affecting the acceleration tube airflow velocity, turbulence intensity, and backflow strength of the sudden expansion region, and other critical fluid characteristics as well. Several proposed models have succeeded in reducing the backflow and outperforming the original design in many different aspects. Models A-60 and C-P, in particular, manage to increase the propulsion force by 37.6% and 20.2% in the acceleration tube while reducing the maximum backflow by 57.1% and 52.2%, respectively. These simulation results can provide invaluable information for the future optimization of the main nozzle.

Huo, X, Jiang, Z, Luo, Q, Li, Q & Sun, G 2022, 'Mechanical characterization and numerical modeling on the yield and fracture behaviors of polymethacrylimide (PMI) foam materials', International Journal of Mechanical Sciences, vol. 218, pp. 107033-107033.
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Polymethacrylimide (PMI) foam materials exhibit great potential in engineering applications due to their lightweight property. Nevertheless, there is lack of constitutive data regarding the PMI foam materials under complex loading conditions; therefore, this paper reports the systematic experimental characterization of the elastic, plastic and fracture properties of PMI foam materials. In this study, the quasi-biaxial stress loading conditions were generated by the Arcan fixture. A 2D digital image correlation (DIC) system was employed to identify the macroscopic deformation in the tests. Based upon the experimental data, a yield surface of the PMI foam material was calibrated and analyzed, in which both low and high densities of PMI foams were taken into account. It was found that the plastic and fracture parameters can be greatly affected by the foam density owing to different microstructure characteristics. Further, fracture behaviors of the PMI foam were experimentally investigated in the context of linear elastic fracture mechanics (LEFM). The critical energy release rates (ERRs) were extracted for the mixed mode I/II by using cracked specimens subjected to combined tension-shear loadings. A homogenized finite element model was developed for the PMI foam materials and validated with the experiment. This study is expected to gain systematic understanding of PMI foam material properties and provide an effective constitutive model for practical applications of PMI foam materials.

Huo, X, Luo, Q, Li, Q, Zheng, G & Sun, G 2022, 'On characterization of cohesive zone model (CZM) based upon digital image correlation (DIC) method', International Journal of Mechanical Sciences, vol. 215, pp. 106921-106921.
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Islam, MS, Rahman, MM, Arsalanloo, A, Beni, HM, Larpruenrudee, P, Bennett, NS, Collins, R, Gemci, T, Taylor, M & Gu, Y 2022, 'How SARS-CoV-2 Omicron droplets transport and deposit in realistic extrathoracic airways', Physics of Fluids, vol. 34, no. 11, pp. 113320-113320.
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The SARS-CoV-2 Omicron variant is more highly transmissible and causes a higher mortality rate compared to the other eleven variants despite the high vaccination rate. The Omicron variant also establishes a local infection at the extrathoracic airway level. For better health risk assessment of the infected patients, it is essential to understand the transport behavior and the toxicity of the Omicron variant droplet deposition in the extrathoracic airways, which is missing in the literature. Therefore, this study aims to develop a numerical model for the Omicron droplet transport to the extrathoracic airways and to analyze that transport behavior. The finite volume method and ANSYS Fluent 2020 R2 solver were used for the numerical simulation. The Lagrangian approach, the discrete phase model, and the species transport model were employed to simulate the Omicron droplet transport and deposition. Different breathing rates, the mouth and nose inhalation methods were employed to analyze the viral toxicity at the airway wall. The results from this study indicated that there was a 33% of pressure drop for a flow rate at 30 l/min, while there was only a 3.5% of pressure drop for a 7.5 l/min. The nose inhalation of SARS-CoV-2 Omicron droplets is significantly more harmful than through the mouth due to a high deposition rate at the extrathoracic airways and high toxicity in the nasal cavities. The findings of this study would potentially improve knowledge of the health risk assessment of Omicron-infected patients.

Islam, MZ, Hossain, SI, Deplazes, E & Saha, SC 2022, 'The steroid mometasone alters protein containing lung surfactant monolayers in a concentration-dependent manner', Journal of Molecular Graphics and Modelling, vol. 111, pp. 108084-108084.
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Mometasone is an investigational anti-inflammatory steroidal drug to treat inflammation via pulmonary administration. For steroid drugs to be effective they need to be adsorbed by lung surfactants, a thin monolayer at the air-water interface in alveoli that reduces surface tension. Information on the molecular-level interactions of the drug with lung surfactants is useful to understand the mechanism of adsorption. In this study, we use coarse-grained molecular dynamics simulation to understand the concentration-dependent effect of mometasone on a lung surfactant monolayer (LSM) composed of lipids and surfactant proteins, under two different breathing conditions (exhalation, at surface tension 0 mNm-1 and inhalation, surface tension 20-25 mNm-1). A series of fixed-APL and fixed-surface tension simulations were used to demonstrate that in the absence of drugs, the model LSM reproduces the surface tensions for the compressed and expanded states, as well as compressibility at different surface tensions. In-depth analysis of simulations of a LSM in the presence of five different drug concentrations shows that mometasone alters the structure and dynamics of the LSM in a concentration-dependent manner. Mometasone induces a collapse in the monolayer that is affected by the surfactant protein and surface tension. Overall, these findings suggest that the surfactant proteins, surface tension and drug concentration are all critical components affecting monolayer stability and drug adsorption. The outcomes of this study may be beneficial for a more in-depth understanding of how mometasone is adsorbed by lung surfactants.

Islam, MZ, Hossain, SI, Deplazes, E, Luo, Z & Saha, SC 2022, 'The concentration-dependent effect of hydrocortisone on the structure of model lung surfactant monolayer by using an in silico approach', RSC Advances, vol. 12, no. 51, pp. 33313-33328.
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Adsorption mechanism of corticosteroid drug hydrocortisone in the lung surfactant monolayer.

Islam, MZ, Krajewska, M, Hossain, SI, Prochaska, K, Anwar, A, Deplazes, E & Saha, SC 2022, 'Concentration-Dependent Effect of the Steroid Drug Prednisolone on a Lung Surfactant Monolayer', Langmuir, vol. 38, no. 14, pp. 4188-4199.
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The lung surfactant monolayer (LSM) is the main barrier for particles entering the lung, including steroid drugs used to treat lung diseases. The present study combines Langmuir experiments and coarse-grained (CG) molecular dynamics simulations to investigate the concentration-dependent effect of steroid drug prednisolone on the structure and morphology of a model LSM. The surface pressure-area isotherms for the Langmuir monolayers reveal a concentration-dependent decrease in area per lipid (APL). Results from simulations at a fixed surface tension, representing inhalation and exhalation conditions, suggest that at high drug concentrations, prednisolone induces a collapse of the LSM, which is likely caused by the inability of the drug to diffuse into the bilayer. Overall, the monolayer is most susceptible to drug-induced collapse at surface tensions representing exhalation conditions. The presence of cholesterol also exacerbates the instability. The findings of this investigation might be helpful for better understanding the interaction between steroid drug prednisolone and lung surfactants in relation to off-target effects.

Jenkin, L, Peng, J & Parnell, J 2022, 'Variability of noise prediction models in catchments featuring significant barriers and noise-enhancing meteorological conditions', The Journal of the Acoustical Society of America, vol. 152, no. 4_Supplement, pp. A129-A129.
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Accurate prediction of noise propagation from industrial sources forms a vital foundation from which to determine noise pollution levels on sensitive communities, as well as informing any mitigation measures required to address unacceptable impacts. A variety of sound propagation model options are available to practitioners in commercial software platforms such as SoundPLAN and CadnaA, and the ability to design effective noise barriers is contingent on the selection of a model that is suitable for the situation under consideration. This is particularly important in noise catchments that feature noise-enhancing meteorological conditions and where significant barriers exist, or are proposed between the industrial estate and potentially noise affected residential communities. In this work, sound levels computed using CONCAWE, ISO 9613-2, Nord2000 and CNOSSOS-EU sound propagation models for homogenous and favourable conditions are compared. The cross-sectional profile of the case study featured in this work is based on a real-world situation in the built-up suburban area of Sydney, Australia. Current findings highlight some key considerations, limitations, and pitfalls associated with older empirically derived sound propagation models.

Jiang, C, Li, W, Deng, M & Ng, C-T 2022, 'Quasistatic pulse generation of ultrasonic guided waves propagation in composites', Journal of Sound and Vibration, vol. 524, pp. 116764-116764.
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Jiang, C, Zhang, C, Li, W, Deng, M & Ng, C-T 2022, 'Assessment of damage in composites using static component generation of ultrasonic guided waves', Smart Materials and Structures, vol. 31, no. 4, pp. 045025-045025.
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Abstract Static component (SC) generation of guided waves (GWs), which combines the high sensitivity of acoustic nonlinearity to micro-damage and low attenuative effect, has great potential for damage assessment in large composite structures. The present work explores the use of SC generation of GWs for assessing damages in carbon fiber reinforced polymer (CFRP) composite laminates. The features including mode, waveform, and cumulative effect of the generated SC in composites are numerically investigated by three-dimensional finite element modeling and simulation. A dynamic displacement measurement method based on piezoelectric transducers is accordingly proposed and experimentally verified. The cumulative SC pulse generated from primary GW tone-burst with a finite duration, is observed and verified numerically and experimentally. It is found that the magnitude of the generated SC pulse is linearly proportional to the quadratic material nonlinearity. Experimental results demonstrate that the generated SC pulse of GW under group velocity matching condition, is an effective means to assess the hygrothermal damage and low-velocity impact damage in CFRP composite plates. The performed experimental examination validates the feasibility of the proposed approach for damage assessment in CFRP composites.

Khezri, M, Hu, Y, Luo, Q, Bambach, MR, Tong, L & Rasmussen, KJR 2022, 'Structural morphing induced by functionalising buckling', Thin-Walled Structures, vol. 181, pp. 110103-110103.
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The paper presents an overview of a research project at the University of Sydney aimed at developing a general framework for the analysis and design of functional components of buildings and structures, where such components achieve large shape changes (morphing) via buckling. The shape changes are optimised, e.g. to reduce energy consumption by minimising solar radiation loads or maximising natural air ventilation. The underlying driver for the project is to develop innovative building technology solutions to reduce the energy consumption of the next generation of low-, medium- and high-rise buildings. The paper first summarises recent work on plate elements supported along three edges, in which temporary intermediate restraints are used to load the plate into the post-buckling range and subsequently released to generate an abrupt shape change in response to an external signal triggered by shading or ventilation demand. This investigation is backed by an analysis of the placement of intermediate restraints to optimise the plate deflection by maximising the pre-buckling compression of the plate. Next, a study is presented on optimising the topology of plates to maximise their shading or ventilation capacities under applied compression or bending. Considering both buckling and nonlinear post-buckling, the analytical framework optimises the spatial distribution of plate thickness. Experiments on optimised plates are reported as well, in which shape memory alloy (SMA) and piezoelectric (PZT) actuators are used to induce compression and buckling. Subsequently, morphing induced by flexural–torsional buckling is investigated where simple 3-member frame geometries are devised to achieve large lateral buckling displacements and twist rotations under low-power external excitation. Lastly, an application of functionalised buckling for shading of buildings is illustrated which employs a bi-stable mechanism powered by shape memory alloy actuation.

Kiss, SH, Katuwandeniya, K, Alempijevic, A & Vidal-Calleja, T 2022, 'Constrained Gaussian Processes With Integrated Kernels for Long-Horizon Prediction of Dense Pedestrian Crowd Flows', IEEE Robotics and Automation Letters, vol. 7, no. 3, pp. 7343-7350.
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Kong, X, Luo, J, Luo, Q, Li, Q & Sun, G 2022, 'Experimental study on interface failure behavior of 3D printed continuous fiber reinforced composites', Additive Manufacturing, vol. 59, pp. 103077-103077.
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Lammers, T, Guertler, M & Skirde, H 2022, 'Can product modularization approaches help address challenges in technical project portfolio management? – Laying the foundations for a methodology transfer', International Journal of Information Systems and Project Management, vol. 10, no. 2, pp. 26-42.
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Formalized Project Portfolio Management (PPM) models struggle to provide comprehensive solutions to project selection, resource allocation and adaptability to dynamic technology project environments. In this article, we introduce a vision for a novel Modular Project Portfolio Management (MPPM) approach by drawing on well-established engineering methods for designing modular product architectures. We show how systems theory can be used to enable a transfer of methods from the area of engineering design and manufacturing to the area of PPM and how the concept of product modularity could help address challenges of existing PPM approaches. This lays the groundwork for the possible development of MPPM as a new and innovative methodology for managing complex technology and engineering project landscapes.

Lammers, T, Rashid, L, Kratzer, J & Voinov, A 2022, 'An analysis of the sustainability goals of digital technology start-ups in Berlin', Technological Forecasting and Social Change, vol. 185, pp. 122096-122096.
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Larpruenrudee, P, Surawski, NC & Islam, MS 2022, 'The Effect of Metro Construction on the Air Quality in the Railway Transport System of Sydney, Australia', Atmosphere, vol. 13, no. 5, pp. 759-759.
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Sydney Metro is the biggest project of Australia’s public transport, which was designed to provide passengers with more trains and faster services. This project was first implemented in 2017 and is planned to be completed in 2024. As presented, the project is currently in the construction stage located on the ground stations of the Sydney Trains Bankstown line (T3). Based on this stage, several construction activities will generate air pollutants, which will affect the air quality around construction areas. Moreover, it might cause health problems to people around there and also the passengers who usually take the train on the T3 line. However, there is no specific data for air quality inside the train that may be affected by the construction from each area. Therefore, the aim of this study is to investigate the air quality inside the train carriage of all related stations from the T3 line. A sampling campaign was conducted over 3 months to analyze particulate matter (PM) concentration, the main indoor pollutants including formaldehyde (HCHO) and total volatile organic compounds (TVOC). The results of the T3 line were analyzed and compared to Airport & South line (T8) that were not affected by the project’s construction. The results of this study indicate that Sydney Metro construction activities insignificantly affected the air quality inside the train. Average PM2.5 and PM10 inside the train of T3 line in the daytime were slightly higher than in the nighttime. The differences in PM2.5 and PM10 concentrations from these periods were around 6.8 μg/m3 and 12.1 μg/m3, respectively. The PM concentrations inside the train from the T3 line were slightly higher than the T8 line. However, these concentrations were still lower than those recommended by the national air quality standards. For HCHO and TVOC, the average HCHO and TVOC concentrations were less than the recommendation criteria.

Li, Z, Gao, W, Yu Wang, M & Luo, Z 2022, 'Design of multi-material isotropic auxetic microlattices with zero thermal expansion', Materials & Design, vol. 222, pp. 111051-111051.
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Liu, X, Wang, L, Luo, Q, Bai, Z, Li, Q & Hu, J 2022, 'A New Stress-Based Formulation for Modeling Notched Fiber-Reinforced Laminates', Polymers, vol. 14, no. 24, pp. 5552-5552.
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Laminated plates are often modeled with infinite dimensions in terms of the so-called Whitney–Nuismer (WN) stress criteria, which form a theoretical basis for predicting the residual properties of open-hole structures. Based upon the WN stress criteria, this study derived a new formulation involving finite width; the effects of notch shape and size on the applicability of new formulae and the tensile properties of carbon-fiber-reinforced plastic (CFRP) laminates were investigated via experimental and theoretical analyses. The specimens were prepared by using laminates reinforced by plain woven carbon fiber fabrics and machined with or without an open circular hole or a straight notch. Standard tensile tests were performed and measured using the digital image correlation (DIC) technique, aiming to characterize the full-field surface strain. Continuum damage mechanics (CDMs)-based finite element models were developed to predict the stress concentration factors and failure processes of notched specimens. The characteristic distances in the stress criterion models were calibrated using the experimental results of un-notched and notched specimens, such that the failure of carbon fiber laminates with or without straight notches could be analytically predicted. The experimental results demonstrated well the effectiveness of the present formulations. The new formula provides an effective approach to implementing a finite-width stress criterion for evaluating the tensile properties of notched fiber-reinforced laminates. In addition, the notch size has a great effect on strength prediction while the fiber direction has a great influence on the fracture mode.

Luo, J, Luo, Q, Zhang, G, Li, Q & Sun, G 2022, 'On strain rate and temperature dependent mechanical properties and constitutive models for additively manufactured polylactic acid (PLA) materials', Thin-Walled Structures, vol. 179, pp. 109624-109624.
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Luo, Q, Tong, L, Bambach, M, Rasmussen, KJR & Khezri, M 2022, 'Active nonlinear buckling control of optimally designed laminated plates using SMA and PZT actuators', Thin-Walled Structures, vol. 181, pp. 110134-110134.
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Luo, Q, Tong, L, Khezri, M, Rasmussen, KJR & Bambach, MR 2022, 'Optimal design of thin laminate plates for efficient airflow in ventilation via buckling', Thin-Walled Structures, vol. 170, pp. 108582-108582.
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Martin-Jimenez, D, Ruppert, MG, Ihle, A, Ahles, S, Wegner, HA, Schirmeisen, A & Ebeling, D 2022, 'Chemical bond imaging using torsional and flexural higher eigenmodes of qPlus sensors', Nanoscale, vol. 14, no. 14, pp. 5329-5339.
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Non-contact atomic force microscopy (AFM) with CO-functionalized tips allows visualizing the chemical structure of individual adsorbed molecules. Particularly high image contrast is observed by exciting a torsional eigenmode of the AFM sensor.

Masangkay, J, Munasinghe, N, Watterson, P & Paul, G 2022, 'Simulation and experimental characterisation of a 3D-printed electromagnetic vibration sensor', Sensors and Actuators A: Physical, vol. 338, pp. 113470-113470.
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Additive manufacturing, also known as 3D printing has already transformed from a rapid prototyping tool to a final end-product manufacturing technique. 3D printing can be used to develop various types of sensors. This paper investigates the ability to use the electromagnetic induction properties of 3D printed carbon-based filament for developing sensors. The paper presents a novel prototype vibration sensor which is 3D-printable, except for an included NdFeB magnet. Motion is detected from the voltage induced by the relative motion of the magnet. The devised vibration sensor is simulated using ANSYS, and a novel prototype is 3D-printed for physical testing to characterise and understand its electromagnetic properties. Simulation helped establish constraints for the design. Two types of experimental setups were physically tested, one setup with a magnet freely sliding inside a cylindrical cavity within an oscillating coil, and the other setup with a stationary coil and oscillating magnet. At a frequency of 10 Hz and a motion travel of about 12 mm, the induced voltage for the moving coil case varied from 5.4 mV RMS for pure sliding motion of the internal magnet to 22.1 mV RMS. The findings of this paper suggest that future sensors can be developed using the electromagnetic induction properties of the carbon-based filament.

Maxwell, IA & Maxwell, NJL 2022, 'A quantitative metric for research impact using patent citation analytics', World Patent Information, vol. 71, pp. 102126-102126.
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Maxwell, IA & Maxwell, NJL 2022, 'A review of Chinese-owned Australian patents', World Patent Information, vol. 71, pp. 102151-102151.
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McCourt, LR, Routley, BS, Ruppert, MG, Keast, VJ, Sathish, CI, Borah, R, Goreham, RV & Fleming, AJ 2022, 'Single-Walled Carbon Nanotubes as One-Dimensional Scattering Surfaces for Measuring Point Spread Functions and Performance of Tip-Enhanced Raman Spectroscopy Probes', ACS Applied Nano Materials, vol. 5, no. 7, pp. 9024-9033.
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This Article describes a method for the characterization of the imaging performance of tip-enhanced Raman spectroscopy probes. The proposed method identifies single-walled carbon nanotubes that are suitable as one-dimensional Raman scattering objects by using atomic force microscope maps and exciting the radial breathing mode using 785 nm illumination. High-resolution cross sections of the nanotubes are collected, and the point spread functions are calculated along with the optical contrast and spot diameter. The method is used to characterize several probes, which results in a set of imaging recommendations and a summary of limitations for each probe. Elemental analysis and boundary element simulations are used to explain the formation of multiple peaks in the point spread functions as a consequence of random grain formation on the probe surface.

Mehami, J, Falque, R, Vidal-Calleja, T & Alempijevic, A 2022, 'Multi-Modal Non-Isotropic Light Source Modelling for Reflectance Estimation in Hyperspectral Imaging', IEEE Robotics and Automation Letters, vol. 7, no. 4, pp. 10336-10343.
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Estimating reflectance is key when working with hyperspectral cameras. The modelling of light sources can aid reflectance estimation, however, it is commonly overlooked. The key contribution of this letter is a physics-based, data-driven model formed by a Gaussian Process (GP) with a unique mean function capable of modelling a light source with an asymmetric radiant intensity distribution (RID) and a configurable attenuation function. This is referred to as the light-source-mean model. Moreover, we argue that by utilising multi-modal sensing information, we can achieve improved reflectance estimation using the proposed light source model with shape information obtained by depth cameras. An existing reflectance estimation method, that solves the dichromatic reflectance model (DRM) via quadratic programming optimisation, is augmented with terms that allow input of shape information. Experiments in simulation show that the light-source-mean GP model had less error when compared to a parametric model. The improved reflectance estimation outperforms existing methods in simulation by reducing the error by 96.8% on average when compared to existing works. We further validate the improved reflectance estimation method through a multi-modal classification application.

Mortazavi, H, Mortazavy Beni, H & Islam, MS 2022, 'Thermal/fluid characteristics of the inline stacked plain‐weave screen as solar‐powered Stirling engine heat regenerators', IET Renewable Power Generation, vol. 16, no. 5, pp. 956-965.
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Ni, Q, Ji, JC, Feng, K & Halkon, B 2022, 'A fault information-guided variational mode decomposition (FIVMD) method for rolling element bearings diagnosis', Mechanical Systems and Signal Processing, vol. 164, pp. 108216-108216.
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Being an effective methodology to adaptatively decompose a multi-component signal into a series of amplitude-modulated-frequency-modulated (AMFM) sub-signals with limited bandwidth, the variational mode decomposition (VMD) has received increasing attention in the diagnosis of rolling element bearings. In implementing VMD, an optimal determination of decomposition parameters, including the mode number and bandwidth control parameter, is the pivotal starting point. However, in practical engineering, heavy background noise, abnormal impulses and vibration interferences from other internal components, often bring great challenges in selecting mode number and bandwidth control parameter. These issues may lead to the performance degradation of VMD for bearing fault diagnosis. Therefore, a fault information-guided VMD (FIVMD) method is proposed in this paper for extracting the weak bearing repetitive transient. To minimize the effects of background noise and/or interferences from other components, two nested statistical models based on the fault cyclic information, incorporated with the statistical threshold at a specific significance level, are used to approximately determine the mode number. Then the ratio of fault characteristic amplitude (RFCA) is defined and utilized to identify the optimal bandwidth control parameter, through which the maximum fault information is extracted. Finally, comparisons with the original VMD, empirical mode decomposition (EMD) and local mean decomposition (LMD) are conducted using both simulation and experimental datasets. Successful fault diagnosis of rolling element bearings under complicated operating conditions, including early bearing fault signals in run-to-failure test datasets, signals with impulsive noise and planet bearing signals, demonstrates that the proposed FIVMD is a superior approach in extracting weak bearing repetitive transients.

Patel, V, Jose, L, Philippot, G, Aymonier, C, Inerbaev, T, McCourt, LR, Ruppert, MG, Qi, D, Li, W, Qu, J, Zheng, R, Cairney, J, Yi, J, Vinu, A & Karakoti, AS 2022, 'Fluoride-assisted detection of glutathione by surface Ce³⁺/Ce⁴⁺ engineered nanoceria', Journal of Materials Chemistry B, vol. 10, no. 47, pp. 9855-9868.
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Nanoceria prepared with different Ce3+/Ce4+ ratios show different oxidase mimetic activities. The activity is enhanced selectively in presence of fluoride ions and used for glutathione detection.

Pietroni, N, Dumery, C, Guenot-Falque, R, Liu, M, Vidal-Calleja, TA & Sorkine-Hornung, O 2022, 'Computational Pattern Making from 3D Garment Models.', CoRR, vol. abs/2202.10272, no. 4, pp. 1-14.
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We propose a method for computing a sewing pattern of a given 3D garment model. Our algorithm segments an input 3D garment shape into patches and computes their 2D parameterization, resulting in pattern pieces that can be cut out of fabric and sewn together to manufacture the garment. Unlike the general state-of-the-art approaches for surface cutting and flattening, our method explicitly targets garment fabrication. It accounts for the unique properties and constraints of tailoring, such as seam symmetry, the usage of darts, fabric grain alignment, and a flattening distortion measure that models woven fabric deformation, respecting its anisotropic behavior. We bootstrap a recent patch layout approach developed for quadrilateral remeshing and adapt it to the purpose of computational pattern making, ensuring that the deformation of each pattern piece stays within prescribed bounds of cloth stress. While our algorithm can automatically produce the sewing patterns, it is fast enough to admit user input to creatively iterate on the pattern design. Our method can take several target poses of the 3D garment into account and integrate them into the sewing pattern design. We demonstrate results on both skintight and loose garments, showcasing the versatile application possibilities of our approach.

Ragazzon, MRP, Messineo, S, Gravdahl, JT, Harcombe, DM & Ruppert, MG 2022, 'The Generalized Lyapunov Demodulator: High-Bandwidth, Low-Noise Amplitude and Phase Estimation', IEEE Open Journal of Control Systems, vol. 1, pp. 69-84.
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Rahman, M, Zhao, M, Islam, MS, Dong, K & Saha, SC 2022, 'Numerical study of nano and micro pollutant particle transport and deposition in realistic human lung airways', Powder Technology, vol. 402, pp. 117364-117364.
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Rahman, MM, Zhao, M, Islam, MS, Dong, K & Saha, SC 2022, 'Nanoparticle transport and deposition in a heterogeneous human lung airway tree: An efficient one path model for CFD simulations', European Journal of Pharmaceutical Sciences, vol. 177, pp. 106279-106279.
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Rees, N, Thiyagarajan, K, Wickramanayake, S & Kodagoda, S 2022, 'Ground-Penetrating Radar Signal Characterization for Non-destructive Evaluation of Low-Range Concrete Sub-surface Boundary Conditions', IEEE Sensors Letters, vol. 6, no. 4, pp. 1-4.
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Romeijn, T, Behrens, M, Paul, G & Wei, D 2022, 'Experimental analysis of water and slurry flows in gravity-driven helical mineral separators', Powder Technology, vol. 405, pp. 117538-117538.
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Romeijn, T, Behrens, M, Paul, G & Wei, D 2022, 'Instantaneous and long-term mechanical properties of Polyethylene Terephthalate Glycol (PETG) additively manufactured by pellet-based material extrusion', Additive Manufacturing, vol. 59, pp. 103145-103145.
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Polyethylene Terephthalate Glycol (PETG) is a highly popular feedstock for extrusion-based additive manufacturing. While data are available on the instantaneous properties of additively manufactured PETG, few research have been done on forecasting the creep behaviour of additively manufactured PETG while accounting for the material altering effects of ageing. This research article aims to enhance the understanding of both the instantaneous and time-dependent mechanical properties of additively manufactured PETG through a series of tensile, FEA simulations, Dynamic Mechanical Analysis (DMA), and two types of creep experiments. The details of experimental and mathematical calculations of the instantaneous and time-dependent properties of additively manufactured PETG are provided. Nine independent material parameters have been determined including three Young's moduli, three shear moduli and three Poisson's ratios, to fully quantify an orthotropic material model of additively manufactured PETG. The printed material exhibited a Young's modulus that is 86.5% of the theoretically possible value in direction 1, a Young's modulus in direction 2 is 66.0% of the theoretical optimum, and a Young's modulus in direction 3 is within 1% of its theoretical maximum. In addition to reporting the creep behaviour of PETG, the novel application of the Time-Temperature Superposition Principle (TTSP) to additively manufactured PETG has been shown to produce an age-affected creep prediction for up to 3.88 years based on samples aged for 221 h and at 23 °C. The methodology and data models have been found to enable predictions for other ages and temperatures. It was concluded that the application of the TTSP creep methodology was limited by the creep test temperature, 60 °C, after which the material began to behave in a non rheologically-simple manner.

Ruppert, MG, Martin-Jimenez, D, Yong, YK, Ihle, A, Schirmeisen, A, Fleming, AJ & Ebeling, D 2022, 'Experimental analysis of tip vibrations at higher eigenmodes of QPlus sensors for atomic force microscopy', Nanotechnology, vol. 33, no. 18, pp. 185503-185503.
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Abstract QPlus sensors are non-contact atomic force microscope probes constructed from a quartz tuning fork and a tungsten wire with an electrochemically etched tip. These probes are self-sensing and offer an atomic-scale spatial resolution. Therefore, qPlus sensors are routinely used to visualize the chemical structure of adsorbed organic molecules via the so-called bond imaging technique. This is achieved by functionalizing the AFM tip with a single CO molecule and exciting the sensor at the first vertical cantilever resonance mode. Recent work using higher-order resonance modes has also resolved the chemical structure of single organic molecules. However, in these experiments, the image contrast can differ significantly from the conventional bond imaging contrast, which was suspected to be caused by unknown vibrations of the tip. This work investigates the source of these artefacts by using a combination of mechanical simulation and laser vibrometry to characterize a range of sensors with different tip wire geometries. The results show that increased tip mass and length cause increased torsional rotation of the tuning fork beam due to the off-center mounting of the tip wire, and increased flexural vibration of the tip. These undesirable motions cause lateral deflection of the probe tip as it approaches the sample, which is rationalized to be the cause of the different image contrast. The results also provide a guide for future probe development to reduce these issues.

Saadallah, A, Abdulaaty, O, Büscher, J, Panusch, T, Morik, K & Deuse, J 2022, 'Early Quality Prediction using Deep Learning on Time Series Sensor Data', Procedia CIRP, vol. 107, pp. 611-616.
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Saadallah, A, Büscher, J, Abdulaaty, O, Panusch, T, Deuse, J & Morik, K 2022, 'Explainable Predictive Quality Inspection using Deep Learning in Electronics Manufacturing', Procedia CIRP, vol. 107, pp. 594-599.
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Saha, SC, Francis, I, Huang, X & Paul, AR 2022, 'Heat transfer and fluid flow analysis in a realistic 16-generation lung', Physics of Fluids, vol. 34, no. 6, pp. 061906-061906.
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Heat transfer between inhaled hot/cool air and the lung surface within the human respiratory system is an intriguing topic that has not received enough attention. The lung can be considered an in vivo heat exchanger, balancing the inhaled air temperature by lowering the hot air temperature and increasing the cool air temperature. The current work studies the unsteady and incompressible airflow motion and heat transfer during inhalation between the surface of the lungs (37 °C) and the inhaled cool air (25 °C) in one case and inhaled hot air (43 °C) in another. Computerized tomography scan (CT-scan) images of the lung of a 39-year-old male patient were processed to generate the airway geometry consisting of 16 generations. The geometry was further modified in UG NX 12.0, and the mesh generation was carried out using Ansys Meshing. The shear stress transport (SST) k−ω turbulent model was employed in Ansys Fluent 20.2 to model the air/lung convective volume heat transfer utilizing a realistic breathing velocity profile. Temperature streamlines, lung volume temperatures, surface heat flux, and surface temperatures on all 16 generations were produced for both cases during the breathing cycle of 4.75 s. Several conclusions were made by studying and comparing the two cases. First, heat transfer between inhaled hot or cool air and the lung surface mainly occurred in the first few generations. Second, airflow temperature patterns are dependent on the inlet breathing velocity profile. Third, the lung volume temperature change directly correlates with the temperature difference between air and the lung surface. Finally, the surface heat flux strongly depended on the heat transfer coefficient. The density, viscosity, thermal conductivity, and specific heat of hot/cool air affected the Reynolds number, Nusselt number, heat transfer coefficient, and surface heat flux.

Sansom, TM, Oberst, S, Richter, A, Lai, JCS, Saadatfar, M, Nowotny, M & Evans, TA 2022, 'Low radiodensity μCT scans to reveal detailed morphology of the termite leg and its subgenual organ', Arthropod Structure & Development, vol. 70, pp. 101191-101191.
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Termites sense tiny substrate-borne vibrations through subgenual organs (SGOs) located within their legs' tibiae. Little is known about the SGOs' structure and physical properties. We applied high-resolution (voxel size 0.45 μm) micro-computed tomography (μCT) to Australian termites, Coptotermes lacteus and Nasutitermes exitiosus (Hill) to test two staining techniques. We compared the effectiveness of a single stain of Lugol's iodine solution (LS) to LS followed by Phosphotungstic acid (PTA) solutions (1% and 2%). We then present results of a soldier of Nasutitermes exitiosus combining μCT with LS + 2%PTS stains and scanning electron microscopy to exemplify the visualisation of their SGOs. The termite's SGO due to its approximately oval shape was shown to have a maximum diameter of 60 μm and a minimum of 48 μm, covering 60 ± 4% of the leg's cross-section and 90.4 ± 5% of the residual haemolymph channel. Additionally, the leg and residual haemolymph channel cross-sectional area decreased around the SGO by 33% and 73%, respectively. We hypothesise that this change in cross-sectional area amplifies the vibrations for the SGO. Since SGOs are directly connected to the cuticle, their mechanical properties and the geometric details identified here may enable new approaches to determine how termites sense micro-vibrations.

Scherer, S, Agrawal, V, Best, G, Cao, C, Cujic, K, Darnley, R, DeBortoli, R, Dexheimer, E, Drozd, B, Garg, R, Higgins, I, Keller, J, Kohanbash, D, Nogueira, L, Pradhan, R, Tatum, M, Viswanathan, V, Willits, S, Zhao, S, Zhu, H, Abad, D, Angert, T, Armstrong, G, Boirum, R, Dongare, A, Dworman, M, Hu, S, Jaekel, J, Ji, R, Lai, A, Lee, YH, Luong, A, Mangelson, J, Maier, J, Picard, J, Pluckter, K, Saba, A, Saroya, M, Scheide, E, Shoemaker-Trejo, N, Spisak, J, Teza, J, Yang, F, Wilson, A, Zhang, H, Choset, H, Kaess, M, Rowe, A, Singh, S, Zhang, J, Hollinger, G & Travers, M 2022, 'Resilient and Modular Subterranean Exploration with a Team of Roving and Flying Robots', Field Robotics, vol. 2, no. 1, pp. 678-734.
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Subterranean robot exploration is difficult, with many mobility, communications, and navigation challenges that require an approach with a diverse set of systems, and reliable autonomy. While prior work has demonstrated partial successes in addressing the problem, here we convey a comprehensive approach to address the problem of subterranean exploration in a wide range of tunnel, urban, and cave environments. Our approach is driven by the themes of resiliency and modularity, and we show examples of how these themes influence the design of the different modules. In particular, we detail our approach to artifact detection, pose estimation, coordination, planning, control, and autonomy, and we discuss our performance in the tunnel, urban, and self-organized cave circuits of the DARPA Subterranean Challenge. Our approach led to a winning result in the tunnel circuit, and placing second in the urban circuit event. We convey lessons learned in designing and testing a resilient system for subterranean exploration that can generalize to a large range of operating conditions, and potential improvements for the future.

Schlegl, T, Schlegl, S, Tomaselli, D, West, N & Deuse, J 2022, 'Adaptive similarity search for the retrieval of rare events from large time series databases', Advanced Engineering Informatics, vol. 52, pp. 101629-101629.
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Improving the recall of information retrieval systems for similarity search in time series databases is of great practical importance. In the manufacturing domain, these systems are used to query large databases of manufacturing process data that contain terabytes of time series data from millions of parts. This allows domain experts to identify parts that exhibit specific process faults. In practice, the search often amounts to an iterative query–response cycle in which users define new queries (time series patterns) based on results of previous queries. This is a well-documented phenomenon in information retrieval and not unique to the manufacturing domain. Indexing manufacturing databases to speed up the exploratory search is often not feasible as it may result in an unacceptable reduction in recall. In this paper, we present a novel adaptive search algorithm that refines the query based on relevance feedback provided by the user. Additionally, we propose a mechanism that allows the algorithm to self-adapt to new patterns without requiring any user input. As the search progresses, the algorithm constructs a library of time series patterns that are used to accurately find objects of the target class. Experimental validation of the algorithm on real-world manufacturing data shows, that the recall for the retrieval of fault patterns is considerably higher than that of other state-of-the-art adaptive search algorithms. Additionally, its application to publicly available benchmark data sets shows, that these results are transferable to other domains.

Schlegl, T, Tomaselli, D, Schlegl, S, West, N & Deuse, J 2022, 'Automated search of process control limits for fault detection in time series data', Journal of Process Control, vol. 117, pp. 52-64.
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Manually defined control limits remain a common strategy for quality control in manufacturing due to their ease of deployment on the shop floor compared to more advanced data analysis approaches. Despite their continued importance, there is no systematic method of defining these control limits. However, sub-optimal control limits can lead to undetected faults or cause unnecessary interruption to production. This manuscript presents an algorithm that systematizes this manual process into an efficient search task. We conceptualized the search task as a sequence of sub-problems that are based on the conventional steps taken by process experts when defining control limits. This algorithm can be integrated into an expert tool for shop floor personnel to automate the definition of control limits in annotated time series data. We demonstrate the efficacy of the control limits found by our algorithm by comparing them to those manually defined by process experts in real-world process data from the automotive industry. Furthermore, we show that our algorithm generalizes to traditional time series classification problems and achieves state-of-the-art performance on selected benchmark datasets. Our work is the first effort in automating the otherwise manual definition of control limits for fault detection.

Schwenken, J, Schallow, J, Sollik, D, Richter, R & Deuse, J 2022, 'Identifikation und Prognose dynamischer Engpässe', Zeitschrift für wirtschaftlichen Fabrikbetrieb, vol. 117, no. 5, pp. 294-299.
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Abstract Eine erhöhte geplante und ungeplante Variabilität innerhalb der Produktion begünstigt das vermehrte Auftreten dynamischer Engpässe. Deren Beherrschung in Form eines zielgerichteten Engpassmanagements gelingt in der Unternehmenspraxis derzeit häufig nur sehr unzureichend und weitestgehend reaktiv. Dieser Beitrag stellt wesentliche Anwenderanforderungen sowie eine Bewertungssystematik und deren Anwendung für ausgewählte Verfahren der Engpassidentifikation und -prognose vor.

Seethaler, R, Mansour, SZ, Ruppert, MG & Fleming, AJ 2022, 'Piezoelectric benders with strain sensing electrodes: Sensor design for position control and force estimation', Sensors and Actuators A: Physical, vol. 335, pp. 113384-113384.
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Piezoelectric benders are widely used in industrial applications due to their low-cost and compact size. However, due to the large relative size and cost of displacement sensors, bender actuators are often operated in open-loop or with feed-forward control, which can limit positioning accuracy to 20% of full-scale. To improve the positioning accuracy of piezoelectric benders, this article proposes integrating resistive strain gauges into the electrode surface by chemical etching or laser ablation. These strain sensors are then used to measure and control the tip displacement. The proposed sensors are shown to suffer from significant cross-coupling between the actuator voltage and measured signal; however, this can be mitigated by judicious choice of the sensor location and actuator driving scheme. In addition to position sensing, a method is also presented for simultaneous estimation of the contact force between the actuator tip and load. The proposed methods are validated experimentally by controlling the tip position of a piezoelectric bender while simultaneously estimating the force applied to a reference load cell.

Seiler, KM, Palmer, AW & Hill, AJ 2022, 'Flow-Achieving Online Planning and Dispatching for Continuous Transportation With Autonomous Vehicles', IEEE Transactions on Automation Science and Engineering, vol. 19, no. 1, pp. 457-472.
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In large-scale industrial applications, goods must be continuously transported between locations, which in the absence of conveyor systems is by a fleet of individual vehicles. This article introduces flow-achieving scheduling tree (FAST), an online dispatching algorithm that allows vehicles to efficiently operate as a team to maximize the system's throughput while meeting a production schedule. A high-performance model is developed for high-fidelity prediction of vehicle interactions and system performance. It is subsequently optimized using a self-tuning variant of Monte Carlo tree search (MCTS) to make agile dispatch decisions in real time. The method is validated using an open-cut mine site and is shown to outperform a commonly used algorithm in this domain. Note to Practitioners - This article was motivated by the problem of dispatching autonomous haul trucks on open-cut mine sites. The proposed method is suited to any industrial transportation system where a continuous stream of goods must be efficiently transported between the load and unload stations by a potentially heterogeneous fleet of automated vehicles. The system makes decisions in real time while reacting to performance variations and disturbances by using a receding horizon approach. Off-the-shelf software commonly used in this domain is based on heuristics with limited ability to optimize, leading to myopic decision making without taking vehicle interactions into account. Here, flow-achieving scheduling tree (FAST) overcomes this by optimizing over possible schedules and thereby implicitly accounting for knock-on effects. Future work will incorporate additional constraints into the optimization process and validate FAST in other industrial domains.

Sepehrirahnama, S & Oberst, S 2022, 'Acoustic Radiation Force and Torque Acting on Asymmetric Objects in Acoustic Bessel Beam of Zeroth Order Within Rayleigh Scattering Limit', Frontiers in Physics, vol. 10.
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Acoustic momentum exchange between objects and the surrounding fluid can be quantified in terms of acoustic radiation force and torque, and depends on several factors including the objects’ geometries. For a one-dimensional plane wave type, the induced torque on the objects with arbitrary shape becomes a function of both, direct polarization and Willis coupling, as a result of shape asymmetry, and has only in-plane components. Here, we investigate, in the Rayleigh scattering limit, the momentum transfer to objects in the non-planar pressure field of an acoustic Bessel beam with axisymmetric wave front. This type of beam is selected since it can be practically realized by an array of transducers that are cylindrically arranged and tilted at the cone angle β which is a proportionality index of the momentum distribution in the transverse and axial propagation directions. The analytical expressions of the radiation force and torque are derived for both symmetric and asymmetric objects. We show the dependence of radiation force and torque on the characteristic parameters β and radial distance from the beam axis. By comparing against the case of a plane travelling plane wave, zero β angle, we demonstrated that the non-planar wavefront of a zeroth order Bessel beam causes an additional radial force and axial torque. We also show that, due to Willis coupling, an asymmetric object experiences greater torques in the θ direction, by minimum of one order of magnitude compared to a plane travelling wave. Further, the components of the partial torques owing to direct polarization and Willis coupling act in the same direction, except for a certain range of cone angle β. Our findings show that a non-planar wavefront, which is quantified by β in the case of a zeroth-order Bessel beam, can be used to con...

Sepehrirahnama, S, Oberst, S, Chiang, YK & Powell, DA 2022, 'Willis Coupling-Induced Acoustic Radiation Force and Torque Reversal', Physical Review Letters, vol. 129, no. 17, p. 174501.
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Acoustic meta-atoms serve as the building blocks of metamaterials, with linear properties designed to achieve functions such as beam steering, cloaking, and focusing. They have also been used to shape the characteristics of incident acoustic fields, which led to the manipulation of acoustic radiation force and torque for development of acoustic tweezers with improved spatial resolution. However, acoustic radiation force and torque also depend on the shape of the object, which strongly affects its scattering properties. We show that by designing linear properties of an object using metamaterial concepts, the nonlinear acoustic effects of radiation force and torque can be controlled. Trapped objects are typically small compared with the wavelength, and are described as particles, inducing monopole and dipole scattering. We extend such models to a polarizability tensor including Willis coupling terms, as a measure of asymmetry, capturing the significance of geometrical features. We apply our model to a three-dimensional, subwavelength meta-atom with maximal Willis coupling, demonstrating that the force and the torque can be reversed relative to an equivalent symmetrical particle. By considering shape asymmetry in the acoustic radiation force and torque, Gorkov's fundamental theory of acoustophoresis is thereby extended. Asymmetrical shapes influence the acoustic fields by shifting the stable trapping location, highlighting a potential for tunable, shape-dependent particle sorting.

Sepehrirahnama, S, Ray Mohapatra, A, Oberst, S, Chiang, YK, Powell, DA & Lim, K-M 2022, 'Acoustofluidics 24: theory and experimental measurements of acoustic interaction force', Lab on a Chip, vol. 22, no. 18, pp. 3290-3313.
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This tutorial review covers theoretical and experimental aspects of acoustic interaction force, as one of the driving forces of acoustophoresis. The non-reciprocity, rotational coupling, viscosity effects, and particle agglomeration are discussed.

Sick, N & Bröring, S 2022, 'Exploring the research landscape of convergence from a TIM perspective: A review and research agenda', Technological Forecasting and Social Change, vol. 175, pp. 121321-121321.
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Convergence at the level of science, technology, market or industry can increasingly be witnessed in a number of empirical settings. It is currently seen as one of the most important influence factors on and trigger for developing innovation strategies. This empirical relevance is mirrored by a surge in publications. Therefore, motivated by a highly dynamic but at the same time rather unstructured body of literature, this review offers a systematic and critical analyses of studies related to Technology and Innovation Management (TIM) research that address convergence from a processual perspective. Four major strands can be identified: (1) drivers and patterns of convergence, (2) anticipation of convergence, (3) strategic reactions to convergence, and (4) convergent products. A key finding of this review is that most contributions have been inward oriented, i.e. understanding the dynamics of convergence. A consequence of this inner focus is that the scientific discourse on convergence has to some degree unfolded independently from its theoretical underpinnings. To this end, this review provides a comprehensive framework of convergence research, including current challenges and emerging themes to address these challenges. The resulting research agenda serves as a starting point to inspire future studies of relevance for theory and conceptual development as well as managerial practice.

Song, Y, Zhang, Z, Wu, J, Wang, Y, Zhao, L & Huang, S 2022, 'A Right Invariant Extended Kalman Filter for Object Based SLAM', IEEE Robotics and Automation Letters, vol. 7, no. 2, pp. 1316-1323.
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With the recent advance of deep learning based object recognition and estimation, it is possible to consider object level SLAM where the pose of each object is estimated in the SLAM process. In this letter, based on a novel Lie group structure, a right invariant extended Kalman filter (RI-EKF) for object based SLAM is proposed. The observability analysis shows that the proposed algorithm automatically maintains the correct unobservable subspace, while standard EKF (Std-EKF) based SLAM algorithm does not. This results in a better consistency for the proposed algorithm comparing to Std-EKF. Finally, simulations and real world experiments validate not only the consistency and accuracy of the proposed algorithm, but also the practicability of the proposed RI-EKF for object based SLAM problem. The MATLAB code of the algorithm is made publicly available.

Sun, G, Wang, Y, Luo, Q & Li, Q 2022, 'Vibration-based damage identification in composite plates using 3D-DIC and wavelet analysis', Mechanical Systems and Signal Processing, vol. 173, pp. 108890-108890.
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High-speed three-dimensional digital image correlation (3D-DIC) techniques can acquire full-field vibration responses under a single excitation, which is not restricted by the number of degrees of freedom (DOFs) in measurement compared with accelerometers and laser Doppler vibrometers (LDVs). Therefore, 3D-DIC exhibits compelling capacity in dynamic testing, especially for nondestructive damage detection. Based on experimental modal analysis (EMA), this study presents a damage detection method without using a baseline model, which combines the advantages of 3D-DIC with two-dimensional continuous wavelet transform (2D-CWT) for damage detection and recognition. The carbon fiber reinforced plastic (CFRP) composite plates with prefabricated artificial damages, including spatial notches and local crack, were investigated. The mode shapes of damaged CFRP composite plates were obtained by singular value decomposition (SVD) from the matrix of frequency response functions (FRFs). Then the mode shapes were analyzed by using wavelet transform, and the damage index was derived from the wavelet coefficients. For comparison, two other damage indices, namely mode shape curvature and polynomial fitting difference, were also derived. It is found that 3D-DIC could provide different measurement DOFs in line with the damage form for post-processing; and the Mexican-hat wavelet analysis can accurately detect the location and size of damage by suppressing the effects of measurement noise.

Sun, G, Wei, Y, Huo, X, Luo, Q & Li, Q 2022, 'On quasi-static large deflection of single lap joints under transverse loading', Thin-Walled Structures, vol. 170, pp. 108572-108572.
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Thiyagarajan, K, Kodagoda, S, Luu, M, Harper, T, Ritchie, D, Prentice, K & Martin, J 2022, 'Intelligent Guide Robots for People who are Blind or have Low Vision: A Review', Vision Rehabilitation International, vol. 13, no. 1, pp. 1-15.
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Wagstyl, D, Borggräfe, T, Oberdiek, S, Wagener, L & Deuse, J 2022, 'Digitale Kollaborationsplattform zur verteilten, agilen Planung im Produktentstehungsprozess', Zeitschrift für wirtschaftlichen Fabrikbetrieb, vol. 117, no. 12, pp. 879-883.
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Abstract Aktuelle Planungsprojekte zur Produktionssystemgestaltung erfordern die Integration zahlreicher Akteure. Zur erfolgreichen, verteilten Kollaboration ist eine geeignete digitale Plattform erforderlich. Die in diesem Beitrag vorgestellte Plattformarchitektur stellt eine aufgabenorientierte Bereitstellung der Planungsdaten vor und zeigt die Verknüpfung mit einem Workflow-Management zur unternehmensinternen Ablauforganisation auf. Die Kollaboration auf der digitalen Plattform wird auf Konzeptebene mit einer agilen Projektplanung und mit einem flexiblen Visualisierungskonzept unterstützt. Abschließend zeigt dieser Beitrag eine exemplarische Integration der IT-Lösung auf und führt Indikatoren ein, welche die Akzeptanz im industriellen Mittelstand erfassen.

Walker, P, Li, T, Khonasty, R, Ponnanna, KM, Kuo, A, Zhao, L & Huang, S 2022, 'Proof of concept study for using UR10 robot to help total hip replacement', The International Journal of Medical Robotics and Computer Assisted Surgery, vol. 18, no. 2, p. e2359.
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AbstractBackgroundThe demand for total hip replacement (THR) for treating osteoarthritis has grown substantially worldwide. The existing robotic systems used in THR are invasive and costly. This study aims to develop a less‐invasive and low‐cost robotic system to assist THR surgery.MethodsA preliminary robotic reaming system was developed based on a UR10 robot equipped with a reamer to cut acetabulum. A novel approach was proposed to cut through a 5 mm hole in femur such that the operation is less invasive to the patients.ResultsThe average error of the cutting hemisphere by the robotic reaming system is 0.1182 mm which is smaller than the average result reaming by hand (0.1301 mm).ConclusionThe robotic reaming can help make THR procedures less invasive and more accurate. Moreover, the system is expected to be significantly less expensive than the robotic systems available in the market at present.

Wang, E, Yao, R, Luo, Q, Li, Q, Lv, G & Sun, G 2022, 'High-temperature and dynamic mechanical characterization of closed-cell aluminum foams', International Journal of Mechanical Sciences, vol. 230, pp. 107548-107548.
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Wang, Q, Liu, D, Carmichael, MG, Aldini, S & Lin, C-T 2022, 'Computational Model of Robot Trust in Human Co-Worker for Physical Human-Robot Collaboration', IEEE Robotics and Automation Letters, vol. 7, no. 2, pp. 3146-3153.
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Trust is key to achieving successful Human-Robot Interaction (HRI). Besides trust of the human co-worker in the robot, trust of the robot in its human co-worker should also be considered. A computational model of a robot's trust in its human co-worker for physical human-robot collaboration (pHRC) is proposed. The trust model is a function of the human co-worker's performance which can be characterized by factors including safety, robot singularity, smoothness, physical performance and cognitive performance. Experiments with a collaborative robot are conducted to verify the developed trust model.

Wang, X, Zheng, J, Ni, Q, Pan, H & Zhang, J 2022, 'Traversal index enhanced-gram (TIEgram): A novel optimal demodulation frequency band selection method for rolling bearing fault diagnosis under non-stationary operating conditions', Mechanical Systems and Signal Processing, vol. 172, pp. 109017-109017.
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It is very important to select the optimal demodulation frequency band (ODFB) of rolling bearing vibration signals for the most valuable fault information extraction and diagnosis. Fast kurtogram (FK) is an effective and most commonly used ODFB selection approach for bearing fault diagnosis, which generally is founded on the filter bank structure and short-time Fourier transform. Though the FK method can effectively detect the shock characteristics of frequency band signals, other useful characteristics related with failure of vibration signal will be ignored. In this paper, a novel ODFB selection method called traversal index enhanced-gram (TIEgram) is proposed for rolling bearing vibration signals. In the proposed TIEgram method, first of all, the traversal segmentation model is utilized to transfer the original signal into frequency domain for enhancing overall segmentation performance of traditional binary trees and 1/3 binary trees structure segmentation models. Then, a new weighted fusion indicator based on the kurtosis, correlation coefficient and spectral negative entropy is designed to select ODFB from the segmented results of traversal segmentation model, which can effectively solve the problem that different vibration signal characteristics cannot be fully detected by a single indicator. After that, an enhanced adaptive multi-scale weighted morphological filtering-based envelope spectrum is employed to demodulate the obtained frequency band for a much more accurate diagnosis effect of rolling bearing. Finally, the simulated and measured signals of rolling bearing under stationary and non-stationary operating conditions are respectively used to verify the feasibility and effectiveness of the proposed method with comparison of the existing FK, Autogram and infogram methods. The comparison analysis results show that TIEgram method can accurately identify the most useful fault information and shows better performance than existing methods.

Wang, Y, Luo, Q, Xie, H, Li, Q & Sun, G 2022, 'Digital image correlation (DIC) based damage detection for CFRP laminates by using machine learning based image semantic segmentation', International Journal of Mechanical Sciences, vol. 230, pp. 107529-107529.
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Vision-based damage detection in carbon fiber-reinforced plastic (CFRP) composites can be interfered by such factors as surface texture, stains and lighting. A digital image correlation (DIC) based surface strain monitoring technique, on the other hand, enables to track the change of strain distribution. It is promising to develop a new approach for online structural health monitoring (SHM), in which the DIC strain contours can be scrutinized automatically and the results are no longer substantially subjected to human interference. In this study, a convolutional neural network (CNN) based image semantic segmentation technique is proposed for pixel-level classification of DIC strain field images. A DeepLabv3+ encoder-decoder architecture combined with different feature extraction networks is investigated. The training dataset and validation of the model are obtained through finite element (FE) simulation. The images of quasi-static axial tensile strain field obtained from 2D-DIC are used to test the accuracy and efficiency of the trained CNN model. It is found that use of a pre-trained ResNet-50 CNN model as the backbone network of DeepLabv3+ architecture through a transfer learning algorithm can make the semantic segmentation results reach a mean intersection over union of 0.9236. The prediction accuracy of the semantic segmentation model trained from the FE data is comparable with that of the model trained from the experimental data, which demonstrates that the proposed machine learning approach for DIC measurement is cost-effective.

Wang, Z, Luo, J, Gong, Z, Luo, Q, Li, Q & Sun, G 2022, 'On correlation of stamping process with fiber angle variation and structural performance of thermoplastic composites', Composites Part B: Engineering, vol. 247, pp. 110270-110270.
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Wang, Z, Luo, Q, Li, Q & Sun, G 2022, 'Design optimization of bioinspired helicoidal CFRPP/GFRPP hybrid composites for multiple low-velocity impact loads', International Journal of Mechanical Sciences, vol. 219, pp. 107064-107064.
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Weibel, J-B, Patten, T & Vincze, M 2022, 'Robust Sim2Real 3D Object Classification Using Graph Representations and a Deep Center Voting Scheme', IEEE Robotics and Automation Letters, vol. 7, no. 3, pp. 8028-8035.
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Wickramanayake, S, Thiyagarajan, K & Kodagoda, S 2022, 'Deep Learning for Estimating Low-Range Concrete Sub-Surface Boundary Depths Using Ground Penetrating Radar Signals', IEEE Sensors Letters, vol. 6, no. 3, pp. 1-4.
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Wickramanayake, S, Thiyagarajan, K, Kodagoda, S & Piyathilaka, L 2022, 'Ultrasonic thickness measuring in-pipe robot for real-time non-destructive evaluation of polymeric spray linings in drinking water pipe infrastructure', Mechatronics, vol. 88, pp. 102913-102913.
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Williams, P, Kirby, R & Karimi, M 2022, 'Sound power radiated from acoustically thick, fluid loaded, axisymmetric pipes excited by a central monopole', Journal of Sound and Vibration, vol. 527, pp. 116843-116843.
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The aim of this study is to determine how the breakout noise of infinite length cylindrical shells excited by a central internal point source differ between acoustically thin and thick walls. This will further our understanding of acoustic radiation from axisymmetric pipes with thick walls, whose breakout noise excited by an internal monopole has not been studied previously. To accomplish this, pipes filled with air and immersed in an external fluid are investigated. This is performed numerically using the semi analytical finite element method to generate predictions above the critical frequency of the duct. It is observed that the maxima in the breakout noise occur when a certain class of eigenmodes with sound energy lying predominantly in the structure veer away from those where the sound energy lies predominantly in the fluid. For lightly fluid loaded pipes with thin walls this veering and associated increase to breakout noise is observed at the ring frequency and above the critical frequency. However for thick walled pipes, no corresponding increase in breakout noise is observed at the critical frequency for a pipe immersed in air. Instead the increase in breakout noise is observed only at the ring frequency and above. However, if the pipe is immersed in water then the increase in breakout noise is observed to occur below the ring frequency.

Wu, H, Wei, D, Hee, AC, Huang, S, Xing, Z, Jiao, S, Huang, H & Jiang, Z 2022, 'The influence of water-based nanolubrication on mill load and friction during hot rolling of 304 stainless steel', The International Journal of Advanced Manufacturing Technology, vol. 121, no. 11-12, pp. 7779-7792.
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AbstractUsing pure water in comparison to water-based lubricant containing 4% TiO2 nanoparticles (NPs), the hot rolling tests of 304 stainless steel were carried out at a rolling temperature of 1050 °C under varying rolling reductions and speeds. The effects of lubrication on rolling force, torque, power and contact friction were systematically investigated. The coefficient of friction (COF) during steady-state hot steel rolling was inversely calculated using a developed flow stress model. The COF models including the effects of rolling reduction and speed were proposed via multiple linear regression. The results indicated that the use of the nanolubricant enabled a reduction of rolling force up to 6.1% and decreases in rolling torque and power up to 21.6%, compared to that of water condition. The results obtained from the linear regression agreed well with those from the inverse calculation, suggesting the developed COF models had high accuracy. The lubrication mechanisms were derived from a boundary lubrication regime, owing to ball bearing and mending effects of TiO2 NPs, and formation of thin lubricant film under high rolling pressure.

Yadav, N, Patel, V, McCourt, L, Ruppert, M, Miller, M, Inerbaev, T, Mahasivam, S, Bansal, V, Vinu, A, Singh, S & Karakoti, A 2022, 'Tuning the enzyme-like activities of cerium oxide nanoparticles using a triethyl phosphite ligand', Biomaterials Science, vol. 10, no. 12, pp. 3245-3258.
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Tuning the enzyme mimetic activity of cerium oxide nanoparticles using triethylphosphine modifies its enzyme mimetic activities and improves the antimicrobial activity.

Yang, Z, Pan, J, Chen, J, Zi, Y, Oberst, S, Schwingshackl, CW & Hoffmann, N 2022, 'A novel unknown-input and single-output approach to extract vibration patterns via a roving continuous random excitation', ISA Transactions, vol. 129, pp. 675-686.
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Ye, K & Ji, JC 2022, 'An origami inspired quasi-zero stiffness vibration isolator using a novel truss-spring based stack Miura-ori structure', Mechanical Systems and Signal Processing, vol. 165, pp. 108383-108383.
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In this paper, an origami-inspired vibration isolator is proposed and numerically investigated to achieve a quasi-zero-stiffness (QZS) property. A truss-spring based stack Miura-ori (TS-SMO) structure is introduced in the vibration isolation system to provide a desired stiffness for high-static-low-dynamic requirement. The proposed TS-SMO structure is different from the traditional origami structures which include rigid facets and deformable creases. It uses coil spring sets to replace all the creases, to improve the physical realization in engineering applications. Nonlinear force response and the QZS feature can be achieved through the geometric nonlinearity and its unique Poisson's ratio profile. The static force and stiffness characteristics of the developed TS-SMO structure are numerically discussed to meet specific feature requirements. Then a QZS vibration isolator is presented under specific parameter design. The force–displacement response and stiffness diagram are obtained to verify the static performance as an isolation system. Furthermore, the displacement transmissibility is derived through dynamic analysis by employing both harmonic balance method (HBM) and numerical simulations. The isolation performance under variable viscous damping is also discussed to examine the effects of the system damping.

Zhao, F, Cao, S, Luo, Q, Li, L & Ji, J 2022, 'Practical design of the QZS isolator with one pair of oblique bars by considering pre-compression and low-dynamic stiffness', Nonlinear Dynamics, vol. 108, no. 4, pp. 3313-3330.
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Various quasi-zero stiffness (QZS) vibration isolators have been developed by using the structures of oblique springs and bars. Towards a practical design, this paper further theoretically and experimentally studies the static and dynamic force of the QZS isolator with one pair of oblique bars by considering pre-compression of horizontal springs and producing an extremely low-dynamic stiffness. By designing the new parameter configuration, two simple formulations are derived on the basis of two QZS conditions to design an improved QZS isolator with a constant low-dynamic stiffness in a wide region around the static equilibrium position. A detailed comparison between the proposed and the existing isolators is made to show the significant improvement on isolation performance. On the basis of the derived formulations, a prototype is fabricated and tested to verify the theoretical formulations and constant low-dynamic stiffness. The experimental results show that the designed QZS isolator can achieve a much wider QZS region to isolate vibration in a larger frequency band and demonstrate a lower displacement transmissibility for the external excitation.

Zhao, S & Burnett, IS 2022, 'Evolutionary array optimization for multizone sound field reproduction', The Journal of the Acoustical Society of America, vol. 151, no. 4, pp. 2791-2801.
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Multizone sound field reproduction aims to generate personal sound zones in a shared space with multiple loudspeakers. Traditional multizone sound field reproduction methods have focused on optimizing the source strengths given a preset array configuration. Recently, however, various methods have explored optimization of the loudspeaker locations. These can be categorized into sparse regularization and iterative methods with existing studies based on numerical simulations and mostly aiming at single-zone sound field reproduction. In this paper, unique experiments compare the state-of-the-art loudspeaker placement optimization methods by selecting a smaller number of loudspeakers from the candidates uniformly placed along a circle. An evolutionary array optimization scheme is proposed and shown to outperform the best existing methods in terms of mean square error in the bright zone and acoustic contrast between the bright and dark zones at frequencies below 1 kHz. The proposed evolutionary optimization scheme is simple, flexible, and can be extended to broadband optimization and other cost functions.

Zhao, S, Li, S, Liu, H, Jiang, J, Wang, M, Liu, H, Wang, W & Wang, Z 2022, 'Quadruple hydrogen bond motif-toughened polybenzoxazine with improved comprehensive performances', Advanced Composites and Hybrid Materials, vol. 5, no. 4, pp. 3057-3067.
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Zhao, S, Zhu, Q, Cheng, E & Burnett, IS 2022, 'A room impulse response database for multizone sound field reproduction (L)', The Journal of the Acoustical Society of America, vol. 152, no. 4, pp. 2505-2512.
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This letter introduces a database of Room Impulse Responses (RIRs) measured in seven different rooms for multizone sound field reproduction research in various acoustic environments. A circular array of 60 loudspeakers was installed in each room, with two microphone arrays placed sequentially in five different zones inside the loudspeaker array. A total of 260 400 RIRs were measured to establish the database. As a demonstration application of the database for multizone sound field reproduction, simulations were performed on the pressure matching and acoustic contrast control methods to investigate how a system optimized with the RIRs measured in one room would perform in other rooms.

Zhao, X, Liu, Y, Wang, Z, Wu, K, Dissanayake, G & Liu, Y 2022, 'TG: Accurate and Efficient RGB-D Feature With Texture and Geometric Information', IEEE/ASME Transactions on Mechatronics, vol. 27, no. 4, pp. 1973-1981.
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Zheng, G, Zhang, L, Wang, E, Yao, R, Luo, Q, Li, Q & Sun, G 2022, 'Investigation into multiaxial mechanical behaviors of Kelvin and Octet-B polymeric closed-cell foams', Thin-Walled Structures, vol. 177, pp. 109405-109405.
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As a class of effective lightweight energy absorption materials, periodic closed-cell foams have been widely applied in engineering, in which the Kelvin and Octet-B foams have demonstrated great value in the research of multiaxial mechanical characteristics. For this reason, this study aims to develop a series of realistic finite element analysis (FEA) models for investigating their uniaxial, compression-shear, and arbitrary triaxial compression performance. Under uniaxial loading conditions, the mechanical responses and deformation modes of the two foams are compared and analyzed with different densities. The influence of different loading angles is also considered under compressive-shear loading. The deformation pattern of foams subject to equal biaxial and hydrostatic loading are compared with uniaxial compression. Based on sufficient simulation data, the initial yield surfaces of the two foams are plotted in the von Mises and mean stress plane, and fitted by three theoretical yield criteria characterized in terms of quadratic functions. It is found that the Miller criterion can better describe the initial yield surface shape of Kelvin foams than the yield models of Deshpande–Fleck and Zhang et al.; while the above yielding models are all of high fitting accuracy for the Octet-B foam. Further, the ability to resist initial yield of the Kelvin foam has proven superior to Octet-B foams by calculating the curve integration. The study is anticipated to provide new insights into novel design and extensive applications of periodic closed-cell foam materials in practice.

Zheng, J, Cao, S, Pan, H & Ni, Q 2022, 'Spectral envelope-based adaptive empirical Fourier decomposition method and its application to rolling bearing fault diagnosis', ISA Transactions, vol. 129, pp. 476-492.
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Zheng, Y, Luo, Z, Wang, Y, Li, Z, Qu, J & Zhang, C 2022, 'Optimized high thermal insulation by the topological design of hierarchical structures', International Journal of Heat and Mass Transfer, vol. 186, pp. 122448-122448.
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Zhong, J, Kirby, R, Karimi, M & Zou, H 2022, 'A spherical wave expansion for a steerable parametric array loudspeaker using Zernike polynomials', The Journal of the Acoustical Society of America, vol. 152, no. 4, pp. 2296-2308.
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A steerable parametric array loudspeaker (PAL) can electronically steer highly directional audio beams in the desired direction. The challenge of modelling a steerable PAL is to obtain the audio sound pressure in both near and far fields with a low computational load. To address this issue, an extension of the spherical wave expansion is proposed in this paper. The steerable velocity profile on the radiation surface is expanded as Zernike polynomials which are an orthogonal and form a complete set over a unit circle. An expression for the radiated audio sound is then obtained using a superposition of Zernike modes. Compared to the existing methods, the proposed expansion is computationally efficient and provides a rigorous transformation of the quasilinear solution of the Westervelt equation without paraxial approximations. The proposed expansion is further extended to accommodate local effects by using an algebraic correction to the Westervelt equation. Numerical results for steering single and dual beams are presented and discussed. It is shown that the single beam can be steered in the desired direction in both near and far fields. However, dual beams cannot be well separated in the near field, which cannot be predicted by the existing far field models.

Zohurul Islam, M, Nath Mondal, R & C. Saha, S 2022, 'Impacts of Rotation on Unsteady Fluid Flow and Energy Distribution through a Bending Duct with Rectangular Cross Section', Energy Engineering, vol. 119, no. 2, pp. 453-472.
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A depth understanding of fluid flow past a curved duct having rectangular cross-section with different aspect ratios (l) are essential for various engineering applications such as in chemical, mechanical, bio-mechanical and bio-medical engineering. So highly ambitious researchers have given significant attention to study new characteristics of fluid flow in a curved duct. The flow characterization in the rectangular duct has been studied over a wide range of numerical and selective experimental studies. However, proper knowledge with the effects of Coriolis force for different aspect ratios is important for better understanding of the transitional behaviour and the subsequent heat generation, which is required to improve further. The purpose of this study is to reveal insight into the transitional flow pattern and heat transfer in a curved rectangular domain. The Navier-Stokes equations are solved using the spectral method, while the Crank-Nicolson method is used to solve the energy equation. An in-house FORTRAN code is developed to get the numerical solution. For post-processing purposes, Tecplot-360 and Ghost-script tools are used. The present study exposes development of Dean vortices that affect heat generation as well as thermal enhancement in the flow with underlying the flow controlling parameters, the Dean number (Dn), the Grashof number (Gr) and the Taylor number (Tr). Time-dependent results followed by phase spaces show that transient flow undergoes in the scenario ‘chaotic → multi-periodic→ periodic → steady-state’ generating 2-to 8-vortices for the periodic/multi-periodic flow at 2000 ≤ Tr ≤ 2205 for l = 2, whereas similar sort of flow is observed in the range of 3100 ≤ Tr ≤ 3195 for l = 3. More complicated 4-to 13-vortex solutions are obtained for the chaotic flow regime at l = 2 in the range of 0 ≤ Tr < 2200 and at l = 3 in the range of 0 ≤ Tr < 3100. The chaotic flow that occurs at the certain range of Tr proficiently intensifies the heat...

Zuo, S, Wang, D, Zhang, Y & Luo, Q 2022, 'Design and testing of a parabolic cam-roller quasi-zero-stiffness vibration isolator', International Journal of Mechanical Sciences, vol. 220, pp. 107146-107146.
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Circular cam-roller (CCR) quasi-zero stiffness (QZS) vibration isolators have been extensively studied. As the CCR isolator can only achieve low stiffness in a very small range and cannot withstand excitation with large amplitude, study on other cam profiles has become interests. This paper investigates a parabolic cam-roller (PCR) QZS vibration isolator. Theoretical formulations of the PCR QZS isolator are derived in detail and the condition of PCR isolator outperforming CCR one is obtained. Design parameters are analyzed and then the optimal design is presented. A prototype of the PCR QZS vibration isolator is fabricated and tested; the corresponding CCR QZS and linear isolators are also experimentally evaluated. In comparison with CCR QZS isolators, the proposed PCR QZS isolators can withstand force and displacement excitations with larger amplitudes in the QZS region. The experimental results validate the present formulation and show that vibration isolation performance of the proposed PCR QZS isolator is much better than that of the CCR QZS isolator and that of the corresponding linear isolator. In comparison with the CCR QZS isolator, the present PCR QZS isolator can have lower stiffness in a wider region around the equilibrium position and lower transmissibility.

Bauer, D, Patten, T & Vincze, M 1970, 'SporeAgent: Reinforced Scene-level Plausibility for Object Pose Refinement', 2022 IEEE/CVF Winter Conference on Applications of Computer Vision (WACV), 2022 IEEE/CVF Winter Conference on Applications of Computer Vision (WACV), IEEE.
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Best, G, Garg, R, Keller, J, Hollinger, GA & Scherer, S 1970, 'Resilient Multi-Sensor Exploration of Multifarious Environments with a Team of Aerial Robots', Robotics: Science and Systems XVIII, Robotics: Science and Systems 2022, Robotics: Science and Systems Foundation.
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Brown, M, Dey, S, Tuxworth, G, Co, J, Bernus, P & Souza, PD 1970, 'An Ility Calculation for Satellite Software Validation', 2022 IEEE Aerospace Conference (AERO), 2022 IEEE Aerospace Conference (AERO), IEEE.
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Byun, H, Zhao, L, Kim, J & Huang, S 1970, 'Comparison Between MATLAB Bundle Adjustment Function and Parallax Bundle Adjustment', 2022 17th International Conference on Control, Automation, Robotics and Vision (ICARCV), 2022 17th International Conference on Control, Automation, Robotics and Vision (ICARCV), IEEE, pp. 60-65.
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Bundle Adjustment (BA) takes a crucial part in Structure from Motion (SfM) which refines a visual reconstruction by optimizing the camera poses and feature positions. The performance of BA can differ depending on the parametrization methods. This paper evaluates two bundle adjustment techniques using standard BA function from MATLAB and Parallax BA. The two BA techniques are compared using data from the 'Starry Night' and 'MALAGA Parking-6L' with different initial inputs. The accuracy and convergence properties of the two BA methods have been evaluated. The effect of the different parameterization techniques and initial information was also analyzed. In most cases, the results of Parallax BA show better accuracy with lower final reprojection error and are less sensitive to the initialization values. It is evaluated that the parallax angle avoids the singularity issue commonly found in Standard BA, which shows that Parallax BA outperforms Standard BA. Furthermore, visual-inertial SLAM (VI-SLAM), based on Parallax BA, has been presented. It is much more reliable than a pure-vision system, showing further improved performance in terms of robustness and accuracy, even with less feature observation. The open-source code can be found in: https://github.com/uts-hb/ParallaxBA.git

Chen, S, Zhao, L, Huang, S & Hao, Q 1970, 'Multi-robot Active SLAM based on Submap-joining for Feature-based Representation Environments', Australasian Conference on Robotics and Automation, ACRA, Australasian Conference on Robotics and Automation, Brisbane.
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The ability to acquire knowledge of the environment actively is essential for autonomous system. In this paper, we propose a multi-robot active simultaneous localization and mapping (SLAM) algorithm based on mutual information for feature-based representation environments that do not depend on the grid map. A multi-layer motion planner and virtual landmarks are introduced to improve exploration efficiency and reduce planning time. To improve the system's accuracy and scalability, we also developed a decentralized version of the active SLAM based on the submap-joining approach. Both simulations and real-world experiments are performed to validate the effectiveness of the proposed methods.

Chi, Z, Wang, S, Li, X, Chang, C-T, Islam, M, Holkar, A, Pronger, S, Liu, T, Lam, K-M & He, X 1970, 'Multi-level unsupervised domain adaption for privacy-protected in-bed pose estimation', International Workshop on Advanced Imaging Technology (IWAIT) 2022, International Workshop on Advanced Imaging Technology (IWAIT 2022), SPIE.
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Cullen, M, Ji, J & Zhao, S 1970, 'Acoustic based GMAW penetration depth identification using droplet transfer monitoring', 2022 IEEE 18th International Conference on Automation Science and Engineering (CASE), 2022 IEEE 18th International Conference on Automation Science and Engineering (CASE), IEEE, pp. 2369-2374.
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Process monitoring and quality control for industrial robotic Gas Metal Arc Welding (GMAW) systems are key components in ensuring the reliability of the produced products. While being a widely used process, there is still a lack of a robust, plug and play monitoring solution. In particular, weld bead penetration depth is a crucial factor in many fabrication applications, where substantial bonding strength is crucial. This paper introduces a new penetration depth estimation method using the emitted acoustic signal to monitor the droplet transfer process. By monitoring the droplet transfer, an estimation of the welding energy transferred to the base material can be obtained while accounting for variations in the welding process. Using this method, the penetration depth is able to be measured within an error of +15%, proving to be a promising solution for online monitoring in robotic welding applications.

Dai, B, Gentil, CL & Vidal-Calleja, T 1970, 'A Tightly-Coupled Event-Inertial Odometry using Exponential Decay and Linear Preintegrated Measurements', 2022 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), 2022 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), IEEE, pp. 9475-9482.
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In this paper, we introduce an event-based visual odometry and mapping framework that relies on decaying event-based corners. Event cameras, unlike conventional cam-eras, can provide sensor data during high-speed motions or in scenes with high dynamic ranges. Rather than providing intensity information at a global shutter rate, events are trig-gered asynchronously depending on whether there is a change in brightness at the pixel location. This novel sensing paradigm calls for unconventional ego-motion estimation techniques to address these new challenges. The key aspect of our framework is the use of a continuous representation of inertial measurements to characterise the system's motion which accommodates the asynchronous nature of the event data while estimating a discrete state in an optimisation-based approach. The proposed method relies on corners extracted from events-only data and associates them with a spatio-temporal locality scheme based on exponential decay. Event tracks are then tightly coupled with temporally accurate preintegrated inertial measurements, allowing for the estimation of ego-motion and a sparse map. The proposed method is evaluated on the Event Camera Dataset showing performance against the state-of-art in event-based visual-inertial odometry.

Deuse, J, Hoffmann, F, Sick, N, Bennett, N, Lammers, T & Hernandez Moreno, V 1970, 'Digitization of the work environment for sustainable production – How could algae based sink technologies enable a neutral Product Carbon Footprint?', Digitization of the work environment for sustainable production, GITO Verlag, pp. 193-205.
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The alarming progress of climate change requires immediate and rigorous action from our society. This also affects the manufacturing industry to a large extent. Many companies have recognised the situation and set themselves ambitious goals with regard to achieving CO2 neutrality. An important step is the detailed analysis of CO2 emissions across the entire supply chain, differentiated by Scopes 1, 2 and 3. Initiated by Siemens, industry and university partners worldwide are currently in the process of founding a non-profit, non-government organisation, called Estainium. Remarkable about the goals of the organisation is that not only CO2 sources, but in particular certified CO2 sinks are to be integrated into the emerging platform. Terrestrial and aquatic sinks without the desired CO2 neutrality could not be achieved must be connected in a clearly traceable and fraud-proof manner. The paper describes the need to create transparency with regard to a product-related carbon footprint and the development of a closed sink system for the accurate carbon capture of emissions generated by value-added processes.

Deuse, J, Sick, N, Guertler, M, Hoffmann, F, Lammers, T & Hernandez Moreno, V 1970, 'Digitization of the work environment for sustainable production How could Digital Technologies enable a neutral Product Carbon Footprint?', Luxemburg.
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Fattoruso, V, Sepehrirahnama, S, Tofigh, F, Lai, JCS, Nowotny, M & Oberst, S 1970, 'CONSIDERATION ON HOW TO IMPROVE GROUND REACTION FORCE MEASUREMENTS IN SMALL WALKING INSECTS', Proceedings of the International Congress on Sound and Vibration, 28th International Congress on Sound and Vibration, Singapore.
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Micro-vibrations caused by the motion of insects, provide a content-rich signal that may be perceived by nestmates, competitors or predators. Knowing the ground reaction forces of a single leg impacting the surface can provide quantitative information about the interaction with the substrate, the substrate itself, physiological and behavioural state of an individual, through mechanistic constraints and the diversity of the gait. Micro-force plates have been used for measuring the ground reaction forces in the order of micro-Newton, using highly sensitive strain gauges attached to compliant load-bearing parts of an underlying mechanical structure. However, their calibration and signal-to-noise-ratio are some of the main challenges of designing these highly sensitive systems. For fine movement analysis, the micro-force plates need to be coupled to high speed video recording systems; the synchronisation of the camera and force plate represents another challenge. For an existing micro-force plate designed for ant measurements, which showed linear signal response in the calibrated force with a lower limit of 120 μN, the linearity of force measurement and sensitivity of the device are investigated in a lower force range, extending the opportunity to study also insects with a lighter footfall. We take into account the difficulties of adapting such devices to the insects' needs related to the environment (i.e. temperature, light...) and morphology (i.e. dimension, weight...). Based on the experiments of the force plate, we consider how to design an experimental setup that overcomes many of the behavioural and technical challenges, to enable more efficient and accurate measurements for insects with body weights less than 5 mg.

Frijat, L, Tomidei, L, Guertler, M & Sick, N 1970, 'Collaborative Robotics: A new work health and safety risk assessment for a novel technology', Asia Pacific Occupational Safety & Health Organization, Melbourne.

Guertler, MR, Adams, N, Caldwell, G, Donovan, J, Hopf, A & Roberts, J 1970, 'A Life-Cycle Framework to Manage Collaboration and Knowledge Exchange in Open Organisations', Proceedings of the Design Society, Cambridge University Press (CUP), pp. 181-190.
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AbstractSuccessful research and development requires interdisciplinary collaboration, often across organisational boundaries and for extended timeframes, such as in innovation networks or ecosystems. Open Organisation (OO) research can support collaboration and knowledge exchange in such situations. It builds on established concepts of Open Innovation through enhancing the exchange of knowledge by the exchange of humans. This paper contributes to OO research by presenting an OO lifecycle framework, which analyses evolving organisational and collaboration characteristics and resulting management needs.

Guertler, MR, Clemon, LM, Bennett, NS & Deuse, J 1970, 'Design for Additive Manufacturing (DfAM): Analysing and Mapping Research Trends and Industry Needs', 2022 Portland International Conference on Management of Engineering and Technology (PICMET), 2022 Portland International Conference on Management of Engineering and Technology (PICMET), IEEE, Portland, Oregon, USA, pp. 1-1.
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Since its early days as a rapid prototyping technology, additive manufacturing has significantly evolved and become an important enabling technology for advanced manufacturing. Despite the benefits, its application in industry is not trivial as, for example, products need to be re-designed and processes changed, and it is not always the optimal manufacturing technology. Design for Additive Manufacturing (DfAM) is a key approach to support the successful use of additive manufacturing in industry and to bridge the gap between research and practice. Aside from design process and technology related methods and tools, DfAM also considers organisational and procedural aspects. To support the success of DfAM and as a result additive manufacturing, it is important to understand how industry needs are addressed by current DfAM methods/tools and related research activities. In this respect, a comprehensive analysis is missing. Therefore, this paper systematically analyses current research topics, fields and trends as well as industry needs and DfAM requirements from an engineering management perspective. Mapping them allows for a systematic discussion between academia and industry to identify the most pressing research needs.

Guo, Z, Halkon, B & Clemon, L 1970, 'Effects of infill parameters on the vibration characteristics of additively manufactured specimens', International Conference on Noise and Vibration Engineering, Leuven, Belgium.

Halkon, B, Perrin, R & Guo, Z 1970, 'INVESTIGATING THE VIBROACOUSTICS OF INDIAN ELEPHANT BELLS', Proceedings of the International Congress on Sound and Vibration, Singapore.
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The geometry of a handmade, 13-tine Indian elephant bell replica, captured with manual measurements and updated using a contemporary and accessible, smartphone-based approach, has been used to generate a simple finite element model. Mode shapes, presented using a novel approach, are compared with those derived from group theory predictions for this bell's symmetries and show excellent agreement for the first two singlets and five of the first six doublets. Natural frequencies are compared with those obtained from an experimental modal analysis campaign using a scanning laser Doppler vibrometer and an automatic modal impact hammer. Again, reasonable agreement is observed for the mode shapes of interest. Results are also qualitatively similar, with appropriate adjustments, to those previously reported in the literature for a 16-tine bell of different design obtained using Electronic Speckle Pattern Interferometry. The results allow us to compare and contrast the effectiveness of these two non-contact optical vibration measurement methods in work of this type on 3D structures.

Hanna, P, Carmichael, M & Clemon, L 1970, 'Benefit of Optimal Actuator Selection – A Comparative Study', Volume 4: Biomedical and Biotechnology; Design, Systems, and Complexity, ASME 2022 International Mechanical Engineering Congress and Exposition, American Society of Mechanical Engineers.
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Abstract Actuators are a vital component, and often the limiting factor in robotics and robotic-related applications like humanoids, exoskeletons, prosthetics and orthosis. Actuator selection is critical due to system design flow-on effects including weight, energy consumption and form factor. A designer’s challenge is often to optimize the actuator to minimize size or weight and meet the performance specifications usually with trade-offs. This paper investigates the design impacts of selecting more suited actuators on the system through a representative humanoid configuration performing a task. It also looks at variations based on the scale of the humanoid using human anthropometric data for variations in limb lengths. The torques and speeds required at each joint to complete the task is simulated and the system design is updated to keep a constant member stress across all designs. The total energy and weight are calculated and used to compare actuator selection impacts. By knowing the extent of the flow-on effects actuator selection has on a configuration, and how this effect scales, designers are able to determine what investment should be allocated to locating the ideal actuator for their task.

Hassan, S, Kim, J & Huang, S 1970, 'An Incremental Robust Underwater Navigation with Expectation-Maximisation', Australasian Conference on Robotics and Automation, ACRA.
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This paper presents a robust navigation solution using low-cost visual-inertial sensors in a 6-Degree of Freedom (DoF) environment. That is an incremental/online navigation solution using the nonlinear least-squares optimisation with classification expectationmaximisation (EM). In this problem, weights are assigned to each measurement observation using the Cauchy function that are iteratively computed from the errors between predicted robot poses and the observed robot measurement. However, the computational cost is quite high in solving the full-batch estimation via Gauss-Newton. By implementing the sliding window filter (SWF), we introduce an incremental EM based robust navigation where the computational cost is shown a significant reduction compared to the full robust batch estimation. The impact of window size on the navigation performance is studied given the dataset is unknown to predict the optimum window gating. This allows a robust constant-time estimation of the robot pose. Such a capability is desirable in underwater navigation applications such as intervention missions. We verify this work using the experimental dataset collected by the UTS submersible pile inspection robot (SPIR).

Hayati, H, Eager, D & Oberst, S 1970, 'Recurrence Plot Qualification Analysis of the Greyhound Rotary Gallop Gait', Springer International Publishing, Sapienza University of Rome, Italy (online), pp. 331-341.
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Holmewood, R, Halkon, B & Darwish, A 1970, 'Towards real-time vibro-acoustic classification, verification and tracking of in-flight UAVs', International Conference on Noise and Vibration Engineering, Leuven, Belgium.

Hossain, M & Eager, D 1970, 'Simulating Theoretical Jerk by Numerical Modelling for Greyhound Racing', Proceedings of the 12th International Conference on Simulation and Modeling Methodologies, Technologies and Applications, 12th International Conference on Simulation and Modeling Methodologies, Technologies and Applications, SCITEPRESS - Science and Technology Publications, Lisbon, PORTUGAL, pp. 379-385.
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Johansen, S, Senaratne, H, Burden, A, Howard, D, Caldwell, GA, Donovan, J, Duenser, A, Guertler, M, Mcgrath, M, Paris, C, Rittenbruch, M & Roberts, J 1970, 'Empowering People in Human-Robot Collaboration: Bringing Together and Synthesising Perspectives', Proceedings of the 34th Australian Conference on Human-Computer Interaction, OzCHI '22: 34th Australian Conference on Human-Computer Interaction, ACM.
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Khatkar, J, Clemon, L & Mettu, R 1970, 'Toolpath Planning With Thermal Stress Awareness for Material Extrusion Additive Manufacturing', Volume 2A: Advanced Manufacturing, ASME 2022 International Mechanical Engineering Congress and Exposition, American Society of Mechanical Engineers.
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Abstract Additive manufacturing has emerged as a next-generation technology for advanced fabrication. Fused Filament Fabrication (FFF) is the most widespread form of material extrusion additive manufacturing and has growing applications in large scale construction. Despite its advantages, FFF is limited by structural weaknesses introduced by cooling of the material between layers. This paper presents an approach to reduce the probability of failure for a given object under known loading conditions through improved toolpath planning which considers temperature decay. Our approach reorders the fabrication sequence to vary the time to print between layers such that the thermal stress induced in fabrication is reduced in regions most likely to fail at the expense of increasing thermally induced stress in less critical areas. In our simulation experiments, we found that our approach offers the greatest improvement when the rate of cooling is large enough for significant temperature decay to occur, but not so large that cooling occurs too quickly for the print order to have any effect. Our approach offers the potential to improve the performance of 3D printed components under known loading conditions by considering the temperature of the print in the planning of the toolpath.

Khatkar, J, Clemon, LM, Fitch, R & Mettu, R 1970, 'A Reeb Graph Approach for Faster 3D Printing.', CASE, 2022 IEEE 18th International Conference on Automation Science and Engineering (CASE), IEEE, pp. 277-282.
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Material extrusion additive manufacturing is an essential technology for rapid prototyping. The standard approach to planning the deposition toolpath for this technology builds each layer sequentially. Unfortunately this approach typically results in significant wasted motion, which is a barrier for use in industrial production. In this paper, we give a new method for toolpath planning that improves on the layer-based approach as well as our own previous methods that build toolpaths across layers. Our approach utilizes a Reeb decomposition on the input model, which is a geometric decomposition that allows toolpath planning over subcomponents of the model rather than over individual extrusion segments. This allows a top-down construction of toolpaths, and is highly effective. We test our new approach, which we call Reeb planning, over a benchmark of 50 models and achieve a reduction of 49.7% in wasted motion over standard layer-based methods. Our decomposition scheme also provides insight into model classification, which can be used for improved production planning.

Khatkar, J, Yoo, C, Fitch, R, Clemon, LM & Mettu, R 1970, 'Coordinated Toolpath Planning for Multi-Extruder Additive Manufacturing.', IROS, 2022 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), IEEE, pp. 10230-10237.
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We present a new algorithm for coordinating the motion of multiple extruders to increase throughput in fused filament fabrication (FFF)/fused deposition modeling (FDM) additive manufacturing. Platforms based on FFF are commonly available and advantageous to several industries, but are limited by slow fabrication time and could be could be significantly improved through efficient use of multiple extruders. We propose the coordinated toolpath planning problem for systems of extruders mounted as end-effectors on robot arms with the objective of maximizing utilization and avoiding collisions. Building on the idea of dependency graphs introduced in our earlier work, we develop a planning and control framework that precomputes a set of multi-layer toolpath segments from the input model and efficiently assigns them to individual extruders such that executed toolpaths are collision-free. Our method overcomes key limitations of existing methods, including utilization loss from workspace partitioning, precomputed toolpaths subject to collisions with the partially fabricated object, and wasted motion resulting from strict layer-by-layer fabrication. We report simulation results that show a major increase in utilization compared to single and multi-extruder methods, and favorable fabrication results using commodity hardware that demonstrate the feasibility of our method in practice.

Larpruenrudee, P, Bennett, NS, Hossain, J, Fitch, R & Islam, MS 1970, 'Hydrogen Energy Storage System: How does the semi-cylindrical helical coil heat exchanger affect metal hydride beds' thermal conductivity?', Australasian Fluid Mechanics Conference, Australasian Fluid Mechanics Conference, Sydney, Australia.
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Metal hydride (MH) is classified as one of the solid material storage technologies for hydrogen storage. This material has been recently used worldwide because of its ability to provide a large hydrogen storage capacity, low operating pressure and high safety. However, the disadvantage of this material is having low thermal conductivity, which leads to it having a slow hydrogen absorption time. For the absorption process, faster heat removal from the MH storage will result in faster absorption. Therefore, enhancing heat transfer performance is one of the most effective ways to improve storage performance. This paper aims to improve the heat transfer performance by employing a semi-cylindrical coil as a heat exchanger embedded inside the storage material. Air is used as the heat transfer fluid (HTF). A comparison of the hydrogen absorption duration and the bed temperature between the semi-cylindrical coil heat exchanger (SCHE) and the traditional helical coil heat exchanger (HCHE) has been made to investigate the effect of heat exchanger configuration designs. These two configurations are designed based on the constant volume of the heat exchanger tube and metal hydride. The numerical simulations are performed by using ANSYS Fluent 2020 R2. The results from this study indicate that the average bed temperature inside the storage by using SCHE is reduced faster than using HCHE, which leads to having a faster hydrogen absorption, approximately 59% time reduction. The key finding from this study could be an important enabler for industrial applications.

Mao, Z, Zhao, L, Huang, S, Fan, Y & Lee, APW 1970, 'DSR: Direct Simultaneous Registration for Multiple 3D Images', Springer Nature Switzerland, pp. 98-107.
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Markham, G, Seiler, KM, Balamurali, M & Hill, AJ 1970, 'Load-Haul Cycle Segmentation with Hidden Semi-Markov Models', 2022 IEEE 18th International Conference on Automation Science and Engineering (CASE), 2022 IEEE 18th International Conference on Automation Science and Engineering (CASE), IEEE.
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Milton, J, Halkon, B, Oberst, S, Chiang, YK & Powell, D 1970, 'SONAR-BASED BURIED OBJECT DETECTION VIA STATISTICS OF RECURRENCE PLOT QUANTIFICATION MEASURES', Proceedings of the International Congress on Sound and Vibration, International Congress on Sound and Vibration, Society of Acoustics, Singapore, Singapore, pp. 1-8.
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Active sonar has been successfully deployed for naval mine countermeasures (MCM) to detect, localise, and classify mines and mine-like objects (MLOs). One of the most challenging problems in MCM operations is the detection and classification of (partially) covered objects; traditional image-based sonar processing techniques cannot readily detect objects within the seabed. In this paper, a processing technique that utilises recurrence plot quantification analysis, a class of nonlinear time series analysis, is proposed for improved covered MLO detection in raw sonar signals. Recurrence plots are binary, graphical visualisations of the recurrence matrix generated from time series data. Following an embedding process to reconstruct a copy of the dynamics in phase space, recurrence plot quantification analysis measures can be extracted and further statistically analysed. Using computationally generated sonar signals extracted from simplified representations of real-world relevant scenarios, this study explores the application of such an approach and its sensitivity to the user-defined parameters for detecting the presence of an MLO, irrespective of the level of burial.

Nerse, C & Oberst, S 1970, 'NUMERICAL VIBRATION ANALYSIS OF HONEYBEE COMB STRUCTURES', Proceedings of the International Congress on Sound and Vibration, International Congress on Sound and Vibration, Singapore.
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Since ancient times much has been written about the geometrical perfection of honeybee comb structures. The hexagonal shape, trademark of the comb cell, has been credited for auxetic mechanical properties and efficient storage of honey. More recent studies on Apis mellifera ligustica have shown that bees have complex nest-building practices through ecological and behavioural evolution. Although mostly dominated by hexagonal cells, the comb structure is shown to feature imperfections due to uneven distribution of worker and drone cells, as well as tilting and merging of cluster of cells. The shape and conditions of the substrate in which the hive is built upon also affects the expansion of the comb structure. Experimental studies have shown that the honeybee comb may have unusual physical properties of vibration amplification and phase reversal. However, the confined nature of these studies poses challenges in understanding the physical mechanisms. In this study, we examine the sensitivity of geometrical and viscoelastic material properties of a honeybee comb on structural vibration transmission. For this purpose, a finite element model of a comb has been developed to obtain modal and frequency response characteristics. The results have shown that lateral deflection of the walls may contribute to efficient vibration transmission at certain resonant frequencies of the cells. Findings might elucidate on why certain frequencies have been observed in experiments, irrespective of the shape and the boundary conditions of the overall honeycomb, and how bees may use this feature to communicate within the colony.

Nerse, C, Oberst, S, Moore, S & MacGillivray, I 1970, 'ASSESSMENT OF FLANKING TRANSMISSIONS IN MEASUREMENTS OF SOUND TRANSMISSION LOSS OF MULTILAYER PANELS', Proceedings of the International Congress on Sound and Vibration, International Congress on Sound and Vibration, Singapore.
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The sound transmission loss measurements of small-sized panels ideally require perfect sealing of the panel frame and a rigid construction of the filler wall that encloses the panels. In practice, suppression of flanking transmission is achieved by having a sufficient isolation between both the source and the receiver rooms and blocking the indirect transmission by installing additional elements on the surfaces of both rooms. At the outer edges of the panel, the frame is supported by acoustically reflective materials and insulations to reduce the energy propagating into the wall. The sound transmission loss of the panels can be improved by installing layers that contribute to additional or more efficient dissipation. These layers are installed in such a way that they are tightly bolted into the frame with a niche being introduced on sides to further secure the panel within the opening. However, for panels with alternating layers of solid and porous materials, or with acoustic cavities, the structural rigidity of the supporting frame and joints are the primary factors that cause the flanking transmission. In this study, we investigate the extent of this transmission, and identify the vibration transmission paths and assess their negligibility in measurement of the sound transmission loss of the multilayer panels. A source-path-receiver approach has been proposed for ranking the critical transmission paths for different panel configurations. For this purpose, a numerical framework has been developed to measure the acoustic response of the room and vibration response of the structural elements at operating conditions. A finite element model in COMSOL is set to validate the results and is compared with an in-house analytical solution which shows good agreements. Assessment of the vibration and acoustic signals at sub-structures reveals transmission paths that are significant for the performance evaluation of multilayer panels.

Okour, M, Falque, R, Vidal-Calleja, T & Alempijevic, A 1970, 'Sim2real Cattle Pose Prediction in 3D pointclouds', Australasian Conference on Robotics and Automation, ACRA, Australasian Conference on Robotics and Automation, ARAA, Brisbane, Australia, pp. 1-8.
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Cattle's body shape and joint articulation carry significant information about their well-being. Building a large dataset of any animals' 3D scans is a challenging task. However, such a dataset is required for training deep learning algorithms for 3D body pose estimation. In this work, we investigate how such a dataset can be constructed for cattle from a single 3D model animated by a digital artist. Further, we reduce the sim2real gap between the virtual dataset and real scans of animals by augmenting the shape of the 3D model to cover the range of possible body shapes. The generated dataset is tested on semantic key points detection with an encoder-decoder architecture.

Paul, G, Tomidei, L, Sick, N, Guertler, M, Carmichael, M & Wambsganss, A 1970, 'Guidelines for Safe Collaborative Robot Design and Implementation', Guidelines for Safe Collaborative Robot Design and Implementation, Guidelines for Safe Collaborative Robot Design and Implementation, Sydney.

Pẽna, F, Mehami, J, Falque, R, Patten, T, Alempijevic, A & Vidal-Calleja, T 1970, 'Subcutaneous Fat Depth Regression Using Hyperspectral and Depth Imaging', Australasian Conference on Robotics and Automation, ACRA, Australasian Conference on Robotics and Automation, ARAA, Brisbane, Australia, pp. 1-10.
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Robotic perception is becoming an important component for automation in the meat processing industry. Whether for contaminant detection or automatic cutting, multimodal perception systems, in particular, based on hyperspectral imaging have the ability to provide information that goes beyond the texture and colour of a surface. In this paper, we present a learning-based method to estimate subcutaneous fat depth in meat cuts by leveraging hyperspectral data models that rely on the knowledge of modelled light sources and surface shape information. Data from a fully calibrated hyperspectral and colour depth (RGB-D) camera system is used as input. Fat depth ground truth is recovered via a novel systematic approach that ray casts a computed tomography (CT) mesh of the meat cuts, which is nonrigidly aligned with a depth reconstruction captured by the RGB-D camera. We thus evaluate machine learning methods that can handle small datasets, by employing dimensionality reduction and data augmentation to address the limited amount of imbalanced data that is acquired. Our results show that leveraging shape and light models, coupled with machine learning methods that capture nonlinearities and spatial correlations produces the most accurate results.

Perrin, R, Halkon, B & Guo, Z 1970, 'Sacred Geometry and Axial Symmetry in the Modern Hand Bell', Acoustical Society of New Zealand (ASNZ) Conference, Acoustical Society of New Zealand (ASNZ) Conference, Wellington, New Zealand.

Polikarpov, M, Emelianov, G, Hubner, F, Farooq, A, Prasad, R, Deuse, J & Schiemann, J 1970, 'Automated Multi-sensory Data Collection System for Continuous Monitoring of Refrigerating Appliances Recycling Plants', 2022 IEEE 27th International Conference on Emerging Technologies and Factory Automation (ETFA), 2022 IEEE 27th International Conference on Emerging Technologies and Factory Automation (ETFA), IEEE.
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Richmond, J & Halkon, B 1970, 'COVERT COLLECTION AND AUTOMATED ANALYSIS OF VIBROACOUSTIC INTELLIGENCE FROM DRONE MOUNTED LASER DOPPLER VIBROMETERS', Proceedings of the International Congress on Sound and Vibration, International Congress on Sound and Vibration, Society of Acoustics, Singapore, pp. 1-8.
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The synthesis of Laser Doppler Vibrometers (LDVs) with autonomous or remotely piloted vehicles such as drones has the potential to enable highly sensitive, non-invasive and discrete vibroacoustic intelligence gathering processes in hostile environments without risk to human life. This work builds upon a previously developed vibroacoustic noise reduction and speaker diarisation system by exploring the effect of feature extraction parameters on diarisation performance. By tuning the Mel Frequency Cepstral Coefficients (MFCC) and x-vector windowing parameters - how many samples are used to produce a single feature vector - the optimal combination was determined to be 0.305 and 0.5 seconds, respectively, resulting in an error of approximately 5%. This work also presents a live or'online' vibroacoustic intelligence processing and analysis system by utilising an open-set clustering algorithm - Real-Time Exponential Filter Clustering (RTEFC). Similarly, the effect of the similarity threshold D and the exponential filter parameter α on diarisation performance was explored. The most effective combination was 0.96 and 0.75, respectively, resulting in an error of approximately 10%. Furthermore, a live transcription stage has also been included using the Microsoft Azure Speech-to-Text API, automating another important intelligence analysis process.

Sansom, T, Sepehrirahnama, S, Halkon, B, Lai, JCS & Oberst, S 1970, 'LASER INTENSITY-INDUCED DAMAGE EFFECTS ON DYNAMIC CHARACTERISATION OF WINGS OF THE EUROPEAN HONEYBEE (APIS MELLIFERA)', Proceedings of the International Congress on Sound and Vibration, International Congress on Sound and Vibration, Singapore.
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Micromechanical and mesoscopic structures including biological tissue, insect appendages or hearing organs can be dynamically characterised through laser Doppler vibrometry (LDV). LDV measures surface vibrations with high spatial resolution, and high dynamic and frequency ranges without causing obvious damage to the specimens. Generally speaking, higher laser intensities lead to higher signal-to-noise ratios, desirable for accurate vibration measurements. However, for certain wavelengths and too high intensity values, the LDV, though only 1 mW output, may damage organic tissue. We aim to illustrate LDV measurements by studying the vibration characteristics of forewings (N= 5) of the European honeybee (Apis mellifera, Hymenoptera). We qualify the level of damage caused by a laser vibrometer with a Helium-Neon laser (532 nm) of a microsystems analyser using a white light-microscope. We monitor the change in the first three eigenfrequencies and the non-damaging intensity level at which the forced-vibration response (FRF) of the wings can still be measured. The first three frequencies at 0.48±0.04 kHz, 1.05±0.06 kHz, and 1.55±0.12 kHz, and their mode shapes of damaged wings are compared against those reported in literature and show ca. 15% frequency deviation. Assuming the stiff element hypothesis, the wing's first bending mode is expected to be at higher frequencies (485±37 Hz) than the approximate wing-beat frequency (234±13.9 Hz). Implementing a finite element model of the wing using a reinforced membrane geometry approach, the measurement results of the undamaged wings are verified. Our results indicate that the intensity levels in LDV measurements on bee wings need to be carefully monitored. The established experimental methodology based on non-damaging laser intensity can also be used for studies of other insects' filigree structures such as their appendages and their vibration and acoustic sensing organs.

Schreiberhuber, S, Weibel, J-B, Patten, T & Vincze, M 1970, 'GigaDepth: Learning Depth from Structured Light with Branching Neural Networks', Springer Nature Switzerland, pp. 214-229.
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Schuhmann, AH, Kleinfeller, N, Sepehrirahnama, S, Oberst, S, Adams, C & Melz, T 1970, 'Numerical analysis on defect detection using structural intensity in solid bodies', Proceedings of the International Congress on Acoustics.
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Analysing structural intensity (SI) offers the possibility to assess the transmission of wave energy within a structure. Measurement of SI has been mainly focused on thin shells and beams. In this work a measurement method is presented to evaluate SI within solid, homogeneous, and isotropic bodies. The method is based on the reciprocity principle, a fundamental assumption in linear vibroacoustics. It allows the reconstruction of the structural intensity field within the bulk of a solid body from the measured surface velocities on the exterior boundaries. From the preliminary results, we demonstrate the capability of this method in approximating the spatial variation of the reconstructed stress and velocity fields using finite element simulation results. Inspired by the reciprocity-based method, we also demonstrate a cavity detection technique using the structural intensity measured along a closed path on a surface of a solid block. Despite some discrepancies in the estimate of the magnitude, the method works well in principle for the benchmark problem of a rectangular cube and it can be verified using our recently set up experimental test. Our proposed method provides an alternative energy-based SI detection technique that may perform as well as those exploiting velocity/acceleration or strain/stress.

Sepehrirahnama, S, McManus, H & Oberst, S 1970, 'ACOUSTIC LEVITATOR-TWEEZER USING PRE-PROGRAMMED ACOUSTIC HOLOGRAMS', Proceedings of the International Congress on Sound and Vibration, 28th International Congress on Sound and Vibration 2022, Singapore.
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Objects in an acoustic field are subjected to acoustic radiation forces, which depend on the objects' scattering behaviour and becomes comparable to the objects' weight for sizes smaller than a few millimeters. This led to manipulation techniques with ultrasonic waves in fluids. In current acoustic levitators, naturally asymmetric objects undergo unwanted spin and rigid-body oscillations. We developed a design of an acoustic manipulator with the ability to levitate and tweeze in vertical and horizontal directions, respectively. This is realised, using three separate transducer arrays and a discretized, reflective floor, inspired by the MIT inForm machine. The floor is made of nine movable pins to change the surface topography and, consequently, manipulate the acoustic field. In this study, we implemented square, staircase, and flat surface configurations to apply pre-defined acoustic holograms for manipulating levitated objects. The two side arrays generate a strong horizontal trap for holding the objects stably at a point where the acoustic radiation force is near zero. The top array and the adjustable floor generate a radiation force as large as an object's weight at the point of levitation, indicated by its levitation height. The object responds to the change of pins by altering its original position in the chamber. Preliminary results obtained at a transducer driving frequency of 40 kHz indicate that an asymmetric object such as a Bee's wing can be levitated stably for more than half an hour with minimal response to external disturbances, and without using phased-array technique. Owing to acoustic radiation force, the measurements are contactless and potentially non-invasive or minimally invasive, dependent on the object. The suggested device design can be potentially employed in the study of delicate biological samples including insects' appendages, such as wings, legs or other filigree structures such as electronic components, wires or MEMS with d...

Smith, W, Qin, Y, Furukawa, T & Dissanayake, G 1970, 'Autonomous Robotic Map Refinement for Targeted Resolution and Local Accuracy', 2022 IEEE International Symposium on Safety, Security, and Rescue Robotics (SSRR), 2022 IEEE International Symposium on Safety, Security, and Rescue Robotics (SSRR), IEEE.
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Sueza Raffa, L, Bennett, NS & Clemon, LM 1970, 'Opportunities for Energy Efficiency Improvements in Craft and Micro-Breweries', Volume 6: Energy, ASME 2022 International Mechanical Engineering Congress and Exposition, American Society of Mechanical Engineers.
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Abstract Rising energy prices and increasing competitiveness in the brewing industry challenge beer producers to reduce costs. To address this issue — and the environmental concerns over climate change — more energy-efficient brewing processes are required. The brewhouse consumes around one-quarter of the total energy demand in a brewery, especially wort boiling, where heat energy in the form of vapour is often wasted and presents a large potential for recovering energy. Although the technology for heat recovery during wort boiling is commercially available for large breweries, the development of equipment technology for craft and micro-breweries still lags behind. Based on a survey of Australian local craft and micro-breweries and a nano-brewery case study, we compare the evaporation rates during wort boiling for different operational parameters and use the results to verify a proposed mathematical model of evaporation from a kettle. We also propose and analyse options for re-utilising the recovered energy, such as pre-heating water for use in a subsequent process or storage for a later brew. Our study shows that the vapour released during the production of one litre of beer has the potential to heat 0.6 to 1.6 litres of water from ambient to 65°C. As for the potential energy savings and environmental impact, the case study nano-brewery can save approximately 5% of the brewhouse’s energy consumption or 2% of the energy required by the entire brewing process, while each surveyed brewery can spare 16 to 133 tonnes of CO2-e from being released into the atmosphere each year. These results reinforce the potential of recovering waste energy from wort boiling vapours in assisting breweries to become more energy-efficient, competitive and environmentally responsible.

Tofigh, F, Sepehrirahnama, S, Lai, JCS & Oberst, S 1970, 'CHARACTERISING AND CALIBRATING PIEZO ACTUATORS FOR MICRO-EXCITATION FOR VIBRATION PLAYBACK IN BI-OASSAYS OF INSECTS', Proceedings of the International Congress on Sound and Vibration, 28th Intenational Congress on Sound and Vibration, Singapore.
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Micro-vibration signals in bioassays under controlled environmental conditions in biotremology require a device that can generate a similar level of vibration response as caused by the insect. Since bioassays often need to be run in environmental cabinets, the space available is limited, and structures to be excited should not be mass loaded. Considering the properties of piezo actuators in generating very short strokes with high frequency and fast response times, stacked arrangements were found suitable for micro-excitation based on a given approximation of a Dirac delta impulse, approximating in the first instance the impact signal of a walking insect. However, at below the current limit of miniaturised force and displacement actuators, it is essential to characterise and calibrate the piezo actuators to ensure they are producing the desired signal at the point of contact on a given structure. Here we established a methodology for driving piezo actuators at the order of μm/s to generate low-amplitude impulsive excitations. The methodology includes finding the transfer function of the piezo actuator and an aluminum and a wood beam (Pinus radiata) of 20x10mm2 cross section and 200mm length. The reaction force from the piezo actuator was measured from about 40mN down to 2mΝ for travel ranges between 1.2μm and 11μm. The results showed that the force varies linearly from 5-19μm for the ceramic, and 0.6μm to 1.4μm for the PI and the MTK actuators with an input voltage ranging from 2-10V. The measurement setup improved using an anechoic chamber to reduce the noise level by one order of magnitude, compared to reported results in literature, and ensure excitation amplitudes as low as ±10nm/s can be measured. The presented methodology allows developing affordable micro-excitors in the future for playback bioassays in confined spaces which cause minimal mass loading on the test specimen.

Tomidei, L, Sick, N, Deuse, J & Clemon, L 1970, 'Production Flow Analysis in the Era of Industry 4.0 : How Digital Technologies can Support Decision-Making in the Factory of the Future', 2022 Portland International Conference on Management of Engineering and Technology (PICMET), 2022 Portland International Conference on Management of Engineering and Technology (PICMET), IEEE.
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Tomidei, L, Sick, N, Guertler, M, Frijat, L, Carmichael, M, Paul, G, Wambsganss, A, Moreno, VH & Hussain, S 1970, 'BEYOND TECHNOLOGY - THE COGNITIVE AND ORGANISATIONAL IMPACTS OF COBOTS', Australasian Conference on Robotics and Automation, ACRA, Australasian Conference on Robotics and Automation, Brisbane.
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Work environments are radically changing with the adoption of new technologies. As the trend for automation grows collaborative robots or 'cobots' are being increasingly adopted by organisations from various industries. As opposed to traditional industrial robots, collaborative robots are complex socio-technical systems that allow close interaction between robots and humans. As a result, these systems can have significant impact on the physical and mental well-being of individuals, and safety can be ensured only by addressing physical, cognitive, and organisational factors. This study aims to provide an understanding of the work practices and behaviours in relation to the cognitive and organisational impact of cobots in Australian industries. By raising awareness of the key challenges and possible solutions to address them, this study provides contributions to academia and industry practice.

Vu, TL, Nguyen, DDK, Sutjipto, S, Le, DT & Paul, G 1970, 'Investigation of Annotation-assisted User Performance in Virtual Reality-based Remote Robot Control', Australasian Conference on Robotics and Automation, ACRA.
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This paper investigates the use of point cloud processing algorithms to provide annotations for robotic manipulation tasks completed remotely via Virtual Reality (VR). A VR-based system has been developed that receives and visualises processed data from real-time RGB-D camera feeds. A point cloud processing algorithm is introduced to annotate targets, and simulated experiments were conducted to validate the efficacy of the proposed algorithm. A real-world robot model has also been developed to provide realistic reactions and control feedback. The targets and the robot model are reconstructed in a VR environment and presented to users with different modalities. The modalities and available information are varied between experimental settings, and the associated task performance is recorded and analysed. The results accumulated from 288 experiments completed by 12 participants indicated that point cloud data is sufficient for task completion. Additional information, neither image stream nor preliminary processes presented as annotations, was found to have a signficant impact on the completion time. However, the combination of image stream and colored point cloud data visualisation modalities was found to greatly enhance a user's performance accuracy, with the number of target centres missed being reduced by 25%.

Vu, TL, Nguyen, DDK, Sutjipto, S, Le, DT & Paul, G 1970, 'Investigation of User Performance in Virtual Reality-based Annotation-assisted Remote Robot Control', Proceedings of the 28th ACM Symposium on Virtual Reality Software and Technology, VRST '22: 28th ACM Symposium on Virtual Reality Software and Technology, ACM, pp. 1-2.
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This poster investigates the use of point cloud processing algorithms to provide annotations for robotic manipulation tasks completed remotely via Virtual Reality (VR). A VR-based system has been developed that receives and visualizes the processed data from real-time RGB-D camera feeds. A real-world robot model has also been developed to provide realistic reactions and control feedback. The targets and the robot model are reconstructed in a VR environment and presented to users in different modalities. The modalities and available information are varied between experimental settings, and the associated task performance is recorded and analyzed. The results accumulated from 192 experiments completed by 8 participants showed that point cloud data is sufficient for completing the task. Additional information, either image stream or preliminary processes presented as annotations, was found to not have a significant impact on the completion time. However, the combination of image stream and colored point cloud data visualization modalities was found to greatly enhance a user's performance accuracy, with the number of target centers missed being reduced by 40%.

West, N, Schwenken, J & Deuse, J 1970, 'Comparative Study of Methods for the Real-Time Detection of Dynamic Bottlenecks in Serial Production Lines', Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 35th International Conference on Industrial, Engineering and Other Applications of Applied Intelligent Systems (IEA/AIE), Springer International Publishing, Kitakyushu, JAPAN, pp. 3-14.
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Capacity-limiting bottlenecks in manufacturing systems form the ideal starting point for measures of improvement. However, the inherent variability of modern systems leads to dynamic bottleneck behavior, causing them to shift between stations. Numerous methods for the detection of shifting bottlenecks exist in literature. In this paper, we present and compare three methods: Bottleneck Walk (BNW), Active Period Method (APM), and an adaptation of Interdeparture Time Variances (ITV). The comparative study deploys the methods in a serial production line with seven stations and eight buffers. We vary the individual locations of the bottlenecks by adding more process time. To compare the methods, we determine the overall average ratio of agreement between the three detection methods. APM and ITV have the highest agreement at an average of 80.10%. Pairings with BNW achieve significantly lower rates of agreement, with 56.33% for ITV, and 62.03%% when compared to the APM.

West, N, Syberg, M & Deuse, J 1970, 'A Holistic Methodology for Successive Bottleneck Analysis in Dynamic Value Streams of Manufacturing Companies', Lecture Notes in Mechanical Engineering, Springer International Publishing, pp. 612-619.
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Numerous methods for bottleneck detection, along novel approaches for bottleneck prediction, are available in literature. To facilitate the development and application of such methods, this paper proposes a holistic methodology for Bottleneck Analysis in dynamic value streams. Analogous to established data analytics levels, namely descriptive, diagnostic, predictive, and prescriptive analytics, the methodology specifies objectives for data-driven Bottleneck Analysis. Based on state-of-the-art bottleneck detection methods, the methodology provides measures for the diagnosis of bottleneck severity and frequency. Additionally, it considers prediction methods to anticipate emerging bottlenecks, depending on available databases. Finally, the methodology provides a context for the yet unexplored field of bottleneck prescription, which aims to mitigate bottleneck effects by data-driven control recommendations. Further practical application of the methodology has to confirm its suitability as a holistic framework for analyzing bottlenecks in dynamic value streams.

Woolfrey, J & Liu, D 1970, 'An Optimal Dynamic Control Method for Robots with Virtual Links', 2022 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), 2022 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), IEEE, pp. 12843-12848.
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Virtual links and virtual joints can be appended to the kinematic chain of a robot arm to assist in modelling and control of certain tasks. Activities such as spray painting, sand blasting, or scanning with a laser or camera can be enhanced by modelling the fluid stream, light beam, or field of view using a virtual link. Virtual joints can be used to allow movement in semi-redundant degrees of freedom of the task space. This can can be exploited to optimize the control of the real robot. A prudent choice is to minimize the effort required by the manipulator to execute the task. This often requires the inversion of the inertia matrix. However, virtual links have no inertia so the inverse does not exist. This paper first explores methods of adding virtual mass or modifying the inertia matrix to allow inversion and the consequences. Then an optimal control problem is proposed that minimizes kinetic energy in the real manipulator and maximizes use of the virtual joints. In doing so, we only need the real inertia matrix which is always invertible. The method is validated in a case study for high pressure water blasting. It is shown to reduce the dynamic torque norm compared to a minimum velocity controller.

Wöstmann, R, Borggräfe, T, Janßen, S, Kimberger, J, Ould, S, Bennett, N, Moreno, VH & Deuse, J 1970, 'Data-driven recipe optimisation based on unified digital twins and shared prediction models', Proceedings of the European Modeling & Simulation Symposium, EMSS, The 34th European Modeling & Simulation Symposium, CAL-TEK srl.
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The importance of cross-process multivariate data analysis for improving products and processes is continuously increasing. Artificial intelligence and machine learning offer new possibilities to represent complex cause-effect relationships in models and to use them for optimisation. For consistent and scalable usage, unified data structures and representations of products, processes and resources are required in order to be able to use larger data populations as well as deploy these models in different application contexts. The paper presents an approach of shared prediction models for recipe optimisation based on unified digital twins in the beverage industry. For this purpose, a central generic data model was created, which is the basis for unified digital twins and thus the integration of physical and digital entities, as well as the foundation for cross-process data analysis.

Xiao, T, Halkon, B, Oberst, S, Wang, S & Qiu, X 1970, 'SOUND FIELD MEASUREMENT AT AN ENCLOSURE OPENING USING REFRACTO-VIBROMETRY', Proceedings of the International Congress on Sound and Vibration, International Congress on Sound and Vibration, Singapore.
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A sound field can be measured by an array of microphones distributed across the area of interest or by moving a smaller number of microphones sequentially. Such procedures can be time-consuming and expensive when high spatial resolution is required. Furthermore, the presence of physical microphones might disturb the sound field. Refracto-vibrometry is based on the acousto-optic effect. It can serve as an alternative method to measure sound pressure at all the points of interest without disturbing the sound field. In this paper, three methods, the filtered back-projection, the truncated singular value decomposition and the Tikhonov regularisation methods, are used to evaluate the sound field at an enclosure opening. Comparison with a microphone array shows that the Tikhonov regularisation method yields the best result.

Xompero, A, Pang, YL, Patten, T, Prabhakar, A, Calli, B & Cavallaro, A 1970, 'Audio-Visual Object Classification for Human-Robot Collaboration', ICASSP 2022 - 2022 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), ICASSP 2022 - 2022 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), IEEE, Singapore, Singapore, pp. 9137-9141.
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Human robot collaboration requires the contactless estimation of the physical properties of containers manipulated by a person for example while pouring content in a cup or moving a food box Acoustic and visual signals can be used to estimate the physical properties of such objects which may vary substantially in shape material and size and also be occluded by the hands of the person To facilitate comparisons and stimulate progress in solving this problem we present the CORSMAL challenge and a dataset to assess the performance of the algorithms through a set of well defined performance scores The tasks of the challenge are the estimation of the mass capacity and dimensions of the object container and the classification of the type and amount of its content A novel feature of the challenge is our real to simulation framework for visualising and assessing the impact of estimation errors in human to robot handovers

Xu, M, Zhao, L, Huang, S & Hao, Q 1970, 'Active SLAM in 3D deformable environments', 2022 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), 2022 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), IEEE, pp. 7952-7958.
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This paper considers active SLAM problem for 3D deformable environments where the trajectory of the robot is planned to optimize the SLAM results. A planning strategy combining an efficient global planner with an accurate local planner is proposed to solve the problem. Simulation results under different scenarios have shown that the proposed active SLAM algorithm provides a good balance between accuracy and efficiency as compared to the local planner and the global planner. The MATLAB code of this first active SLAM algorithm for 3D deformable environments is made publicly available4.

Ye, K, Ji, JC & Hu, D 1970, 'Dynamic Analysis of a Novel Zero-Stiffness Vibration Isolator by Considering Frictional Force Involved', Lecture Notes in Electrical Engineering, Springer Singapore, pp. 544-553.
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This study proposes a novel zero-stiffness vibration isolator and investigates its dynamic responses under micro-oscillation with a friction consideration. The novel vibration isolator is based on the mechanism of a cam-roller Quasi-Zero-Stiffness (QZS) system while with improvement by reducing its system components. The proposed vibration isolator consists of a designed bearing, which can provide stiffness responses in the radial direction, and an inserted rod with curved surface. Without the precise cooperation between the positive and negative stiffness systems required in a typical QZS isolator, the designed single stiffness system can provide the high-static-low-dynamic stiffness characteristic directly. The static characteristics of the stiffness performance are numerically confirmed, and then the dynamic responses with friction consideration at the contact surfaces are discussed. The displacement transmissibility in low frequency range is numerically validated when applying harmonic excitation on the base. The analysis results of this study reveal a unique vibration isolating performance of the zero-stiffness system under frication consideration.

Zhang, S, Zhao, L, Huang, S, Wang, H, Luo, Q & Hao, Q 1970, 'SLAM-TKA: Real-time Intra-operative Measurement of Tibial Resection Plane in Conventional Total Knee Arthroplasty', Medical Image Computing and Computer Assisted Intervention – MICCAI 2022, Springer Nature Switzerland, pp. 126-135.
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Total knee arthroplasty (TKA) is a common orthopaedic surgery to replace a damaged knee joint with artificial implants. The inaccuracy of achieving the planned implant position can result in the risk of implant component aseptic loosening, wear out, and even a joint revision, and those failures most of the time occur on the tibial side in the conventional jig-based TKA (CON-TKA). This study aims to precisely evaluate the accuracy of the proximal tibial resection plane intra-operatively in real-time such that the evaluation processing changes very little on the CON-TKA operative procedure. Two X-ray radiographs captured during the proximal tibial resection phase together with a pre-operative patient-specific tibia 3D mesh model segmented from computed tomography (CT) scans and a trocar pin 3D mesh model are used in the proposed simultaneous localisation and mapping (SLAM) system to estimate the proximal tibial resection plane. Validations using both simulation and in-vivo datasets are performed to demonstrate the robustness and the potential clinical value of the proposed algorithm.

Zhao, S & Burnett, I 1970, 'Adaptive personal sound zones systems with online plant modelling', The 24th International Congress on Acoustics, The 24th International Congress on Acoustics, Gyeongju, Korea.

Zhao, S & Burnett, IS 1970, 'Time-Domain Acoustic Contrast Control with A Spatial Uniformity Constraint for Personal Audio Systems', ICASSP 2022 - 2022 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), ICASSP 2022 - 2022 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), IEEE, Singapore, Singapore, pp. 1061-1065.
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Personal audio systems with multiple sound zones for listeners to enjoy different music/audio contents privately in a shared physical space have attracted great research interest in the past two decades. Acoustic Contrast Control (ACC) is one of the most popular methods for generating multiple personal sound zones because it produces the minimum inter-zone interference. However, the ACC method has been found to be inferior to the pressure matching method in terms of sound quality due to an uneven frequency response and nonuniform spatial sound field distribution in the bright zone. This paper proposes a spatial uniformity constraint on time-domain broadband ACC in addition to the frequency response trend estimation constraint with the aim of ensuring a uniform sound field distribution in the bright zone. Simulation results with measured room impulse responses demonstrate that the proposed algorithm reduces the magnitude variations in the bright zone to be less than 1 dB higher than the just noticeable level difference at a cost of a perceptually negligible degradation in acoustic contrast.

Zhou, S, Eager, D, Halkon, B, Walker, P, Covey, K & Braiden, S 1970, 'INVESTIGATION AND COMPARISON OF THE SOUND QUALITY OF THE LURES USED FOR GREYHOUND RACING', Proceedings of the International Congress on Sound and Vibration.
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This study investigates and compares the acoustic signatures of a traditional wire-cable pulled lure system and two novel alternative battery-operated lure systems which were developed to eliminate the hazardous steel-wire cable and make the sport of greyhound racing safer for greyhounds, participants, and spectators. The acoustical measurements of these three lure systems were conducted at the Murray Bridge greyhound racing track in South Australia with high-frequency B&K Type 4191 microphones. The microphones were positioned within the starting box and on the track adjacent to the starting boxes, at both the straight track and bending track. The measurements captured the sounds that the greyhounds hear before and after the opening of the starting box gate. The sound quality analysis was conducted to compare the lure sounds. It was found when the battery-lure was installed with all nylon rollers, it presented less sound energy than the traditional wire-cable pulled lure. When two of the nylon rollers were replaced with steel rollers, the battery-operated lure emitted a louder sound than the traditional wire-cable-pulled lure. The different acoustic characteristics of these lure systems suggest future research is warranted on the reaction of greyhounds to different lure sounds, particularly their excitement level within the starting box as the lure approaches. This initial research also suggests some greyhounds may not clearly hear the battery-operated lure with all nylon rollers approaching the starting boxes and the timing of these greyhounds to jump may be delayed, particularly during high wind conditions.

Zhou, S, Eager, D, Halkon, B, Walker, P, Covey, K & Braiden, S 1970, 'Investigation and Comparison of the Sound Quality the Wirecable Lure and Battery-Operated Lure used for Greyhound Racing', International Congress on Sound and Vibration, Singapore.

Zhu, M & Zhao, S 1970, 'Broadband loudspeaker placement optimization for personal sound zones systems', Proceedings of the International Congress on Acoustics, The 24th International Congress on Acoustics, Gyeongju, Korea.
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Personal sound zones system has attracted considerable attention in the past decades due to its potential for private audio generation in public spaces. Various methods have been explored to optimize the driving signals of loudspeakers that are placed to form a regular array, such as circular, linear, and arc-shaped arrays. Recently, loudspeaker placement optimization has been investigated by researchers to reduce the number of loudspeakers without remarkable sacrifice in performance. Existing loudspeaker placement optimization algorithms have been designed in the frequency domain and the optimized loudspeaker arrangements depend on frequency, which is undesirable in practical applications. To overcome this problem, this paper explores broadband loudspeaker placement optimization for multizone sound field reproduction based on a time-domain evolutionary array optimization method. Simulations with measured room impulse responses are performed to select a smaller number of loudspeakers from 60 candidate loudspeakers that are uniformly placed along a circle. Simulation results demonstrate the optimized array achieves a higher acoustic contrast with a lower array effort than the empirical arc-shaped array, when the same number of loudspeakers are selected.

Darwish, A, Oberst, S & Halkon, B University of Technology Sydney 2022, Hexapod payload report, no. v1, Centre for Audio, Acoustics and Vibration, Faculty of Engineering and IT, University of Technology Sydney.

Guertler, M, Carmichael, M, Paul, G, Sick, N, Tomidei, L, Hernandez Moreno, V, Wambsganss, A, Amin, M, Cockburn, J, Frijat, L & Hussain, S NSW Government: Centre for Work Health and Safety 2022, Guidelines for the Safe Collaborative Robot Design and Implementation, NSW Government: Centre for Work Health and Safety.
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Funded through the NSW Workers Compensation Operational Fund.

Halkon, B, Guo, Z & Darwish, A UTS 2022, Fatigue Load Test on Worthington Rail Floor Panels for EM - Final Report, UTS.

Halkon, B, Milton, J, Oberst, S, Powell, D, Chiang, YK & Phung, SL UTS 2022, Enhanced detection, localisation and identification of sand-covered naval mines using novel hybrid signal processing methods, UTS.

Trianni, A, Bennett, N & Lindsay, D Aus Industry Cooperative Research Centres Program 2022, Industry 4.0 for energy productivity – Opportunity Assessment for Research Theme B2, Final Report, no. Project Code: 21.B2.A.0229, Sydney, Australia.
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This opportunity assessment report explores the various benefits, barriers, regulation, and business modelscurrently available for Industry 4.0 technologies. Industry 4.0 technologies aim to improve energyproductivity within industry I.e., the ability to shift part or whole [industrial] energy usage to times of theday when it is either/both cheaper and more economical with renewable energy sources. Given thecomplexity of Industry 4.0 technical features (Artificial Intelligence (AI), sensors, big data & analytics,Internet of Things (IoT)), the breadth of analysis this report provides insights into how to unlock futurepotential by leveraging benefits and overcoming barriers to this technological transition.

Chen, C, Ding, L, Liu, B, Du, Z, Liu, Y, Di, X, Shan, X, Lin, C, Zhang, M, Xu, X, Zhong, X, Wang, J, Chang, L, Halkon, BJ, Chen, X, Cheng, F & Wang, F 2022, 'Exploiting dynamic nonlinearity in upconversion nanoparticles for super-resolution imaging'.

Falque, R, Vidal-Calleja, T & Alempijevic, A 2022, 'Semantic keypoint extraction for scanned animals using multi-depth-camera systems'.

He, Y, Wang, J, Su, D, Nakadai, K, Wu, J, Huang, S, Li, Y & Kong, H 2022, 'Observability Analysis of Graph SLAM-Based Joint Calibration of Multiple Microphone Arrays and Sound Source Localization'.

Hernandez Moreno, V, Carmichael, MG & Deuse, J 2022, 'Towards Learning by Demonstration for Industrial Assembly Tasks', Institute of Electrical and Electronics Engineers (IEEE).
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Hernandez Moreno, V, Carmichael, MG & Deuse, J 2022, 'Towards Learning by Demonstration for Industrial Assembly Tasks', Institute of Electrical and Electronics Engineers (IEEE).
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Islam, MS, Larpruenrudee, P, Rahman, MM, Luo, Z, Sauret, E & Gu, Y 2022, 'A CFD-DEM Model for Particle Transport in Airways', MDPI AG.
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Seiler, KM 2022, 'Haul Road Mapping from GPS Traces'.