Chotiprayanakul, P, Liu, DK & Dissanayake, G 2012, 'Human-robot-environment interaction interface for robotic grit-blasting of complex steel bridges', AUTOMATION IN CONSTRUCTION, vol. 27, pp. 11-23.
View/Download from: Publisher's site
View description>>
This paper presents a human-robot-environment interaction (HREI) interface using haptic feedback for a grit-blasting robot operating in close proximity to a complex steel bridge structure. The productivity requirements dictate the need for efficient algorithms for mapping, exploration, and collision-free motion planning. While a large portion of the grit-blasting operation can be automated, a tele-operation is essential to deal with some difficult to access sections such as edges, complex corners, and surfaces which can only be approached through hole. A 3-dimensional virtual force field (3D-VF 2) method is developed for capturing the relationship between the robot and its environment. A novel haptic force generation method and a workspace mapping algorithm allow intuitive interaction between the operator and the robot through haptic feedback. The strategies presented are verified in extensive simulations and experiments conducted on a steel bridge with a prototype grit-blasting robot. © 2012 Elsevier B.V.
Herath, DC, Kodagoda, S & Dissanayake, G 2012, 'A two-tier map representation for compact-stereo-vision-based SLAM', ROBOTICA, vol. 30, pp. 245-256.
View/Download from: Publisher's site
View description>>
Vision sensors are increasingly being used in the implementation of Simultaneous Localization and Mapping (SLAM). Even though the mathematical framework of SLAM is well understood, considerable issues remain to be resolved when a particular sensing modal
Khushaba, RN, Greenacre, L, Kodagoda, S, Louviere, J, Burke, S & Dissanayake, G 2012, 'Choice modeling and the brain: A study on the Electroencephalogram (EEG) of preferences', EXPERT SYSTEMS WITH APPLICATIONS, vol. 39, no. 16, pp. 12378-12388.
View/Download from: Publisher's site
View description>>
Choice conjures the idea of a directed selection of a desirable action or object, motivated by internal likes and dislikes, or other such preferences. However, such internal processes are simply the domain of our human physiology. Understanding the physiological processes of decision making across a variety of contexts is a central aim in decision science as it has a great potential to further progress decision research. As a pilot study in this field, this paper explores the nature of decision making by examining the associated brain activity, Electroencephalogram (EEG), of people to understand how the brain responds while undertaking choices designed to elicit the subjects' preferences. To facilitate such a study, the Tobii-Studio eye tracker system was utilized to capture the participants' choice based preferences when they were observing seventy-two sets of objects. These choice sets were composed of three images offering potential personal computer backgrounds. Choice based preferences were identified by having the respondent click on their preferred one. In addition, a brain computer interface (BCI) represented by the commercial Emotiv EPOC wireless EEG headset with 14 channels was utilized to capture the associated brain activity during the period of the experiments. Principal Component Analysis (PCA) was utilized to preprocess the EEG data before analyzing it with the Fast Fourier Transform (FFT) to observe the changes in the main principal frequency bands, delta (0.5-4 Hz), theta (4-7 Hz), alpha (8-12 Hz), beta (13-30 Hz), and gamma (30-40 Hz). A mutual information (MI) measure was then used to study left-to-right hemisphere differences as well as front-to-back difference. Eighteen participants were recruited to perform the experiments with the average results showing clear and significant change in the spectral activity in the frontal (F3 and F4), parietal (P7 and P8) and occipital (O1 and O2) areas while the participants were indicating their...
Khushaba, RN, Kodagoda, S, Takruri, M & Dissanayake, G 2012, 'Toward improved control of prosthetic fingers using surface electromyogram (EMG) signals', EXPERT SYSTEMS WITH APPLICATIONS, vol. 39, no. 12, pp. 10731-10738.
View/Download from: Publisher's site
View description>>
A fundamental component of many modern prostheses is the myoelectric control system, which uses the electromyogram (EMG) signals from an individual's muscles to control the prosthesis movements. Despite the extensive research focus on the myoelectric con
Kirchner, N & Alempijevic, A 2012, 'A Robot Centric Perspective on the HRI Paradigm', Journal of Human-Robot Interaction, vol. 1, no. 2, pp. 135-157.
View/Download from: Publisher's site
View description>>
The industrial revolution undoubtedly defined the role of machines in our society, and it directly shaped the paradigm for human machine interaction - a paradigm which was inherited by the field of Human Robot Interaction (HRI) as the machines became robots. This paper argues that, for a foreseeable set of interactions, reshaping this paradigm would result in more effective and more often successful interactions. This paper presents our Robot Centric paradigm for HRI. Evidence in the form of summaries of relevant literature and our past efforts in developing social-robotics enabling technology is presented to support our paradigm. A definition and a set of recommendations for designing the key enabling component, sociocontextual cues, of our paradigm are presented. Finally, empirical evidence generated through a number of experiments and field studies (N = 456 and N = 320) demonstrates our paradigm is both feasibly incorporated into HRI and moreover, yields significant contributions to the successfulness of a set of HRIs.
Pasian, B, Sankaran, S & Boydell, S 2012, 'Project management maturity: a critical analysis of existing and emergent factors', International Journal of Managing Projects in Business, vol. 5, no. 1, pp. 146-157.
View/Download from: Publisher's site
View description>>
PurposeThe purpose of this paper is to report on the findings of a doctoral thesis examining the limitations of project management maturity and associated models. It examines the management of undefined projects where the definition, repeatability and predictability of processes cannot be reasonably expected. The challenge to project management maturity theorists is to recognize the possibility of project management maturity in an environment characterized by undefined project elements and the requirement for greater flexibility in their management.Design/methodology/approachThis inquiry was supported by a multimethod (MXM) research design with two stages: a content/textual analysis of two different collections of maturity models, and an exploratory case study of two university sites. The analysis (supported by grounded theory techniques) contributed to the development of a 4‐node conceptual framework that was used as the primary data collection instrument at two Canadian university sites.FindingsResults indicate that multiple non‐process factors can contribute to a mature project management capability. These can include context‐specific values, specialized bodies of knowledge (instructional design), customer involvement, third‐party influence, and tacit “human factors” such as trust and creativity. The demands of this inquiry also demonstrated the need for a new data collection sequence in multimethod research design theory.Practical implicationsPractitioners are encouraged to consider customer involvement, organizational dynamics and adaptable variables such as leadership (among other non‐process f...
Qayyum, U, Martin, A, Kim, J & Shim, DH 2012, 'Omni-VISER: 3D omni vision-laser scanner', Australasian Conference on Robotics and Automation, ACRA.
View description>>
Three dimensional perception has drawn significant attention recently partly due to the success of Kinect and 3D lidar such as Velodyne. Although quite successful, they still have some limitations such as limited sensing range or high costs prohibiting them for small-scale outdoor applications. This paper presents a novel 3D scanning system by integrating a continuously rotating laser head with an omni-directional vision which offers a full 360° field of view with sweeping range measurements. An extrinsic calibration procedure is also proposed, in which point correspondences are being used instead of calibration object. Key benefits of the proposed system are 1) the capability to provide full 3D measurements after each revolution and 2) a real-time texture based 3D mapping. The paper presents the experimental results of prototype hardware for 3D point cloud generation with texture and feature detection. An open source implementation of real-time point cloud generation is also made available.
Sheffield, J, Sankaran, S & Haslett, T 2012, 'Systems thinking: taming complexity in project management', On the Horizon, vol. 20, no. 2, pp. 126-136.
View/Download from: Publisher's site
View description>>
Project Management and Systems Thinking overlap. In a software development world where the problems with today's legacy system are a consequence of yesterday's enterprise-wide solution, it is useful to understand cycles of cause and effect and their attendant time delays. As system complexity increases, systems thinking becomes increasingly important in generating debate and insight about an uncertain and changing environment. Surprisingly, project managers do not seem to use simple systems thinking tools even though these provide unique benefits in framing and solving problems that arise from multiple perspectives and relationships. The purpose of this paper is to introduce systems thinking and describe its application to the management of complexity in projects. It is based on a subject developed and taught by two of the authors if the paper in a Master of Project Management Course offered at the University of Technology Sydney to help project managers use systems thinking approaches to deal with project complexity. The subject evolved over a three year period using an action research approach to improve the subject to meet the needs of the students as well as the increasingly complex environment that they face in their projects. In this paper systems thinking is positioned in the evolution of the project management discipline, and its relationship to complex systems explored. Selected concepts are then described and applied to the three phases (concept, implementation and evaluation) of the system development lifecycle.
Singh, SPN & Waldron, KJ 2012, 'A stance period approach for simplified observation of galloping as applied to canines', Robotica, vol. 30, no. 4, pp. 627-633.
View/Download from: Publisher's site
View description>>
SUMMARYThe gallop is the preferred gait by mammals for agile traversal through terrain. This motion is intrinsically complex as the feet are used individually and asymmetrically. Simple models provide a conceptual framework for understanding this gait. In this light, this paper considers the footfall projections as suggested by an impulse model for galloping as a measurement simplifying strategy. Instead of concentrating on forces and inverse dynamics, this view focuses observations on leg motion (footfalls and stance periods) for subsequent gallop analysis and parameter estimation. In practice, this eases experiments (particularly for IR-based motion capture) by extending the experimental workspace, removing the need for single-leg contact force-plate measurements, and reducing the marker set. This provides shorter setup times, and it reduces postprocessing as data are less likely to suffer from occlusion, errant correspondence, and tissue flexion. This approach is tested using with three canine subjects (ranging from 8 to 24 kg) performing primarily rotary gallops down a 15 m runway. Normalized results are in keeping with insights from previous animal and legged robot studies and are consistent with motions suggested by said impulse model.
Solà, J, Vidal-Calleja, T, Civera, J & Montiel, JMM 2012, 'Impact of Landmark Parametrization on Monocular EKF-SLAM with Points and Lines', International Journal of Computer Vision, vol. 97, no. 3, pp. 339-368.
View/Download from: Publisher's site
View description>>
This paper explores the impact that landmark parametrization has in the performance of monocular, EKFbased, 6-DOF simultaneous localization and mapping (SLAM) in the context of undelayed landmark initialization. Undelayed initialization in monocular SLAM challenges EKF because of the combination of non-linearity with the large uncertainty associated with the unmeasured degrees of freedom. In the EKF context, the goal of a good landmark parametrization is to improve the model's linearity as much as possible, improving the filter consistency, achieving robuster and more accurate localization and mapping. This work compares the performances of eight different landmark parametrizations: three for points and five for straight lines. It highlights and justifies the keys for satisfactory operation: the use of parameters behaving proportionally to inverse-distance, and landmark anchoring. A unified EKF-SLAM framework is formulated as a benchmark for points and lines that is independent of the parametrization used. The paper also defines a generalized linearity index suited for the EKF, and uses it to compute and compare the degrees of linearity of each parametrization. Finally, all eight parametrizations are benchmarked employing analytical tools (the linearity index) and statistical tools (based on Monte Carlo error and consistency analyses), with simulations and real imagery data, using the standard and the robocentric EKF-SLAM formulations. © 2011 Springer Science+Business Media, LLC.
Ahmad, A, Huang, S, Wang, JJ, Dissanayake, G & IEEE 1970, 'A New State Vector and a Map Joining Algorithm for Range-Only SLAM', 2012 12TH INTERNATIONAL CONFERENCE ON CONTROL, AUTOMATION, ROBOTICS & VISION (ICARCV), International Conference on Control, Automation, Robotics and Vision, IEEE, Guangzhou, China, pp. 1024-1029.
View/Download from: Publisher's site
View description>>
This paper presents a new state vector and a map joining algorithm for range-only SLAM problems. Local maps are built by least squares optimization using the new state vector and a landmark initialization strategy which is an improvement on our preliminary work [1]. The map joining algorithm combines the local maps using least squares optimization to maintain the estimation consistency. Both the local map building and the map joining algorithm maintain a list of 'unused range observations' to minimize the potential for information loss. The accuracy of the proposed method is evaluated using a simulation dataset, and an experimental dataset provided by the Robotics Institute at Carnegie Mellon University (CMU). © 2012 IEEE.
Ahmad, A, Zhao, L, Huang, S, Dissanayake, G & IEEE 1970, 'Convergence Comparison of Least Squares Based Bearing-Only SLAM Algorithms Using Different Landmark Parametrizations', 2012 12TH INTERNATIONAL CONFERENCE ON CONTROL, AUTOMATION, ROBOTICS & VISION (ICARCV), International Conference on Control, Automation, Robotics and Vision, IEEE, Guangzhou, China, pp. 1006-1011.
View/Download from: Publisher's site
View description>>
This paper compares the convergence of least squares based 2D bearing-only SLAM algorithms using different landmark parametrizations. It is shown that the requirement on the accuracy of the initial value vary significantly when using different landmark parametrizations. Especially, for small scale bearing-only SLAM problems, the region of attraction of the global minimum for Gauss-Newton iteration based bearing-only SLAM algorithm using parallax angle landmark parametrization is significantly larger as compared with those of bearing-only SLAM algorithms using other landmark parametrizations. © 2012 IEEE.
Amirsadri, A, Bishop, AN, Kim, J, Trumpf, J & Petersson, L 1970, 'A computationally efficient low-bandwidth method for very-large-scale mapping of road signs with multiple vehicles', 15th International Conference on Information Fusion, FUSION 2012, IEEE, pp. 1351-1358.
View description>>
This paper provides a flexible solution to the problem of building and maintaining a very-large-scale map using multiple vehicles. In particular, we consider producing a map of landmarks on the scale of thousands of kilometres in an outdoor environment. The algorithm is distributed across multiple vehicles each given the task of producing and updating a local map. The vehicles are equipped with a range of sensors and selectively communicate maps to and from a central station in a bandwidth-constraint environment. The potentially overlapping local maps are asynchronously transmitted back to a central fusion centre where a global map repository is maintained. The work addresses two of the most common issues of mapping in large-scale environments, namely, computational complexity and limited communication bandwidth. The proposed communication architecture is scalable and is capable of dealing with time-varying overlapping map sizes. A general data fusion framework based on covariance intersection is proposed to tackle the problem of redundant information propagation that is caused by communicating sub-maps of arbitrary size in the network. We also provide an analysis on the applicability of covariance intersection, as compared to the optimal approach when no cross-correlation is known between estimates from different vehicles. We further analyse the solution using a number of illustrative examples. © 2012 ISIF (Intl Society of Information Fusi).
Amirsadri, A, Jonghyuk Kim, Petersson, L & Trumpf, J 1970, 'Practical considerations in precise calibration of a low-cost MEMS IMU for road-mapping applications', 2012 American Control Conference (ACC), 2012 American Control Conference - ACC 2012, IEEE, pp. 881-888.
View/Download from: Publisher's site
Carmichael, MG & Dikai Liu 1970, 'A task description model for robotic rehabilitation', 2012 Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2012 34th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), IEEE, San Diego, CA, pp. 3086-3089.
View/Download from: Publisher's site
View description>>
The desire to produce robots to aid in physical neurorehabilitation has led to the control paradigm Assistance-As-Needed. This paradigm aims to assist patients in performing physical rehabilitation tasks whilst providing the least amount of assistance required, maximizing the patient's effort which is essential for recovery. Ideally the provided assistance equals the gap between the capability required to perform the task and the patient's available capability. Current implementations derive a measure of this gap by critiquing task performance based on some criteria. This paper presents a task description model for tasks performed by a patient's limb, allowing physical requirements to be calculated. Applied to two upper limb tasks typical of rehabilitation and daily activities, the effect of task variations on the task's physical requirements are observed. It is proposed that using the task description model to compensate for changing task requirements will allow better support by providing assistance closer to the true needs of the patient. © 2012 IEEE.
Gan, SK, Fitch, R, Sukkarieh, S & IEEE 1970, 'Real-Time Decentralized Search with Inter-Agent Collision Avoidance', 2012 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION (ICRA), IEEE International Conference on Robotics and Automation, IEEE, Saint Paul, MN, USA, pp. 504-510.
View/Download from: Publisher's site
View description>>
This paper addresses the problem of coordinating a team of mobile autonomous sensor agents performing a cooperative mission while explicitly avoiding inter-agent collisions in a team negotiation process. Many multi-agent cooperative approaches disregard the potential hazards between agents, which are an important aspect to many systems and especially for airborne systems. In this work, team negotiation is performed using a decentralized gradient-based optimization approach whereas safety distance constraints are specifically designed and handled using Lagrangian multiplier methods. The novelty of our work is the demonstration of a decentralized form of inter-agent collision avoidance in the loop of the agents' real-time group mission optimization process, where the algorithm inherits the properties of performing its original mission while minimizing the probability of inter-agent collisions. Explicit constraint gradient formulation is derived and used to enhance computational advantage and solution accuracy. The effectiveness and robustness of our algorithm has been verified in a simulated environment by coordinating a team of UAVs searching for targets in a large-scale environment. © 2012 IEEE.
Himstedt, M, Alempijevic, A, Zhao, L, Huang, S & Boehme, H-J 1970, 'Towards robust vision-based self-localization of vehicles in dense urban environments', 2012 IEEE/RSJ International Conference on Intelligent Robots and Systems, 2012 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS 2012), IEEE, Algarve, Portugal, pp. 3152-3157.
View/Download from: Publisher's site
View description>>
Self-localization of ground vehicles in densely populated urban environments poses a significant challenge. The presence of tall buildings in close proximity to traversable areas limits the use of GPS-based positioning techniques in such environments. This paper presents an approach to global localization on a hybrid metric-topological map using a monocular camera and wheel odometry. The global topology is built upon spatially separated reference places represented by local image features. In contrast to other approaches we employ a feature selection scheme ensuring a more discriminative representation of reference places while simultaneously rejecting a multitude of features caused by dynamic objects. Through fusion with additional local cues the reference places are assigned discrete map positions allowing metric localization within the map. The self-localization is carried out by associating observed visual features with those stored for each reference place. Comprehensive experiments in a dense urban environment covering a time difference of about 9 months are carried out. This demonstrates the robustness of our approach in environments subjected to high dynamic and environmental changes. © 2012 IEEE.
Hu, G, Huang, S, Zhao, L, Alempijevic, A & Dissanayake, G 1970, 'A robust RGB-D SLAM algorithm', 2012 IEEE/RSJ International Conference on Intelligent Robots and Systems, 2012 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS 2012), IEEE, Algarve, Portugal, pp. 1714-1719.
View/Download from: Publisher's site
View description>>
Recently RGB-D sensors have become very popular in the area of Simultaneous Localisation and Mapping (SLAM). The major advantage of these sensors is that they provide a rich source of 3D information at relatively low cost. Unfortunately, these sensors in their current forms only have a range accuracy of up to 4 metres. Many techniques which perform SLAM using RGB-D cameras rely heavily on the depth and are restrained to office type and geometrically structured environments. In this paper, a switching based algorithm is proposed to heuristically choose between RGB-BA and RGBD-BA based local maps building. Furthermore, a low cost and consistent optimisation approach is used to join these maps. Thus the potential of both RGB and depth image information are exploited to perform robust SLAM in more general indoor cases. Validation of the proposed algorithm is performed by mapping a large scale indoor scene where traditional RGB-D mapping techniques are not possible. © 2012 IEEE.
Kassir, A, Fitch, R, Sukkarieh, S & IEEE 1970, 'Decentralised Information Gathering with Communication Costs', 2012 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION (ICRA), IEEE International Conference on Robotics and Automation, IEEE, Saint Paul, MN, USA, pp. 2427-2432.
View/Download from: Publisher's site
View description>>
Advantages of decentralised decision making systems for multi-agent robotic tasks are limited by the heavy demand they impose on communication. This paper presents an approach to control communication for the LQ team problem, namely a team of agents with linear dynamics and quadratic team cost. Communication costs are added to the objective of the LQ optimal control linear matrix inequality formulation, allowing for a well-defined balancing of communication costs and team performance. Results show a reduction in communication consistent with the specified cost and in a manner that upholds team performance relative to the reduced communication footprint. The applicability of the approach has also been extended to information gathering tasks through local LQ approximations along the agents' paths. Simulation testing on a sample two-agent problem shows a 40% reduction in communication with negligible impact on performance. © 2012 IEEE.
Khushaba, RN, Kodagoda, S & IEEE 1970, 'Electromyogram (EMG) Feature Reduction Using Mutual Components Analysis for Multifunction Prosthetic Fingers Control', 2012 12TH INTERNATIONAL CONFERENCE ON CONTROL, AUTOMATION, ROBOTICS & VISION (ICARCV), International Conference on Control, Automation, Robotics and Vision, IEEE, Guangzhou, China, pp. 1534-1539.
View/Download from: Publisher's site
View description>>
Surface Electromyogram (EMG) signals are usually utilized as a control source for multifunction powered prostheses. A challenge that arises with the current demands of such prostheses is the ability to accurately control a large number of individual and combined fingers movements and to do so in a computationally efficient manner. As a response to such a challenge, we present a combined feature selection and projection algorithm, denoted as Mutual Components Analysis (MCA). The proposed MCA algorithm extends the well-known Principal Components Analysis (PCA) by pruning the noisy and redundant features before projecting the data. To implement the feature selection step, the mutual information concept is utilized to implement a new information gain evaluation function. The performance and significance of the proposed MCA is demonstrated on EMG datasets collected for the purpose of this research from eight subjects with eight electrodes attached on their forearm. Fifteen classes of fingers movements where considered in this paper with MCA achieving >95% accuracy on average across all subjects. © 2012 IEEE.
Khushaba, RN, Kodagoda, S, Dissanayake, G, Greenacre, L, Burke, S, Louviere, J & IEEE 1970, 'A Neuroscientific Approach to Choice Modeling: Electroencephalogram (EEG) and User Preferences', 2012 INTERNATIONAL JOINT CONFERENCE ON NEURAL NETWORKS (IJCNN), IEEE International Joint Conference on Neural Networks, IEEE, Brisbane, Australia, pp. 1-8.
View/Download from: Publisher's site
View description>>
Paper available at: http://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=&arnumber=6252561&contentType=Conference+Publications&sortType%3Ddesc_p_Publication_Year%26queryText%3Dkhushaba
Khushaba, RN, Lei Shi & Kodagoda, S 1970, 'Time-dependent spectral features for limb position invariant myoelectric pattern recognition', 2012 International Symposium on Communications and Information Technologies (ISCIT), 2012 International Symposium on Communications and Information Technologies (ISCIT), IEEE, Surfers Paradise, Gold Coast, Australia, pp. 1015-1020.
View/Download from: Publisher's site
View description>>
Recent studies on the myoelectric control of powered prosthetics revealed several factors that affect its clinical performance. One of the important factors is the variation in the limb position associated with normal use which can have a substantial impact on the robustness of Electromyogram (EMG) pattern recognition. To solve this problem, we propose in this paper a new feature extraction algorithm based on set of spectral moments that extracts the relevant information about the EMG power spectrum in an accurate and efficient manner. The main goal is to rely on effective knowledge discovery and pattern recognition methods to discover the neural information embedded in the EMG signals regardless of the limb position. Specifically, the proposed features define descriptive qualities for the general time domain-based characterization of the EMG spectral amplitude, spectral sparsity, and irregularity factor by the application of mathematical-statistical methods which also include frequency consideration. The performance of the proposed spectral moments is tested on EMG data collected from eight subjects, while implementing eight classes of movements, each at five different limb positions. Practical results indicate that training the classifier on the EMG moments collected from multiple positions and testing on completely unseen positions can achieve significant reduction in the classification error rates of upon â10% on average across all subjects and limb ositions.
Kim, S & Kim, J 1970, 'Building large-scale occupancy maps using an infinite mixture of Gaussian process experts', Australasian Conference on Robotics and Automation, ACRA.
View description>>
This paper proposes a novel method of occupancy map building for large-scale applications. Although Gaussian processes have been successfully applied to occupancy map building, it suffers from high computational complexity of O(n3), where n is the number of training data, limiting its use for large-scale mappings. We propose to take a divide-and-conquer approach by partitioning training data into manageable subsets by combining a Dirichlet process mixture on top of a Gaussian process, which turns into an infinite mixtures of Gaussian process experts. Experimental results with simulated data show that our method produces accurate occupancy maps while maintaining the scalability.
Kim, S & Kim, J 1970, 'Building occupancy maps with a mixture of Gaussian processes', 2012 IEEE International Conference on Robotics and Automation, 2012 IEEE International Conference on Robotics and Automation (ICRA), IEEE, IEEE, pp. 4756-4761.
View/Download from: Publisher's site
Kirchner, N, Alempijevic, A, Virgona, A & IEEE 1970, 'Head-to-shoulder signature for person recognition', 2012 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION (ICRA), IEEE International Conference on Robotics and Automation, IEEE, St Paul, MN, USA, pp. 1226-1231.
View/Download from: Publisher's site
View description>>
Ensuring that an interaction is initiated with a particular and unsuspecting member of a group is a complex task. As a first step the robot must effectively, expediently and reliably recognise the humans as they carry on with their typical behaviours (in situ). A method for constructing a scale and viewing angle robust feature vector (from analysing a 3D pointcloud) designed to encapsulate the inter-person variations in the size and shape of the people's head to shoulder region (Head-to-shoulder signature - HSS) is presented. Furthermore, a method for utilising said feature vector as the basis of person recognition via a Support-Vector Machine is detailed. An empirical study was performed in which person recognition was attempted on in situ data collected from 25 participants over 5 days in a office environment. The results report a mean accuracy over the 5 days of 78.15% and a peak accuracy 100% for 9 participants. Further, the results show a considerably better-than-random (1/23 = 4.5%) result for when the participants were: in motion and unaware they were being scanned (52.11%), in motion and face directly away from the sensor (36.04%), and post variations in their general appearance. Finally, the results show the HSS has considerable ability to accommodate for a person's head, shoulder and body rotation relative to the sensor - even in cases where the person is faced directly away from the robot.
Lie, S, Liu, DK & Bongers, B 1970, 'A cooperative approach to the design of an Operator Control Unit for a semi-autonomous grit-blasting robot', Australasian Conference on Robotics and Automation, ACRA, Australasian Conference on Robotics and Automation, Australian Robotics and Automation Association (ARAA), Wellington, New Zealand, pp. 1-7.
View description>>
Due to the diverse range of applications that robots cover today, Human Robot Interaction interface design has become an equally diverse area. This diverse area is characterised by the different types of end users that make use of the robots. For robots to be useful to end users their needs have to be well understood by the robotics development teams. One approach that facilitates understanding the end users needs is Cooperative Design. This paper presents the results of a study that took a Cooperative Design approach to the design and development of a robotic Operator Control Unit. The results presented here demonstrate that end users involved in the cooperative design approach thought it added important value to the design outcome, that they enjoyed the process and that it helped build interpersonal relationships within the development team.
Liu, M, Huang, S, Dissanayake, G, Wang, H, IEEE & Japan, RSO 1970, 'A Convex Optimization Based Approach for Pose SLAM Problems', 2012 IEEE/RSJ INTERNATIONAL CONFERENCE ON INTELLIGENT ROBOTS AND SYSTEMS (IROS), IEEE/RSJ International Conference on Intelligent Robots and Systems, IEEE, Algarve, Portugal, pp. 1898-1903.
View/Download from: Publisher's site
View description>>
This paper demonstrates that 2D pose SLAM has an underlining near convex structure when formulated as a least squares (LS) optimization problem. By introducing new variables and some approximations, the LS pose SLAM problem can be formulated as a quadratically constrained quadratic programming (QCQP) problem. The QCQP formulation can then be relaxed into a semi-definite programming (SDP) problem which is convex. Unique solution to the convex SDP problem can be obtained without initial state estimate and can be used to construct a candidate solution to the original LS pose SLAM problem. Simulation datasets and the Intel Research Lab dataset have been used to demonstrate that when the relative pose information contain noises with reasonable level, the candidate solution obtained through the relaxation is very close to the optimal solution to the LS SLAM problem. Thus in practice, the candidate solution can serve as either an approximate solution or a good initial guess for a local optimization algorithm to obtain the optimal solution to the LS pose SLAM problem. © 2012 IEEE.
McAllister, R, Peynot, T, Fitch, R, Sukkarieh, S, IEEE & Japan, RSO 1970, 'Motion Planning and Stochastic Control with Experimental Validation on a Planetary Rover', 2012 IEEE/RSJ INTERNATIONAL CONFERENCE ON INTELLIGENT ROBOTS AND SYSTEMS (IROS), IEEE/RSJ International Conference on Intelligent Robots and Systems, IEEE, Vilamoura, Portugal, pp. 4716-4723.
View/Download from: Publisher's site
View description>>
Motion planning for planetary rovers must consider control uncertainty in order to maintain the safety of the platform during navigation. Modelling such control uncertainty is difficult due to the complex interaction between the platform and its environment. In this paper, we propose a motion planning approach whereby the outcome of control actions is learned from experience and represented statistically using a Gaussian process regression model. This model is used to construct a control policy for navigation to a goal region in a terrain map built using an on-board RGB-D camera. The terrain includes flat ground, small rocks, and non-traversable rocks. We report the results of 200 simulated and 35 experimental trials that validate the approach and demonstrate the value of considering control uncertainty in maintaining platform safety. © 2012 IEEE.
Miro, JV, Poon, J, Huang, S & IEEE 1970, 'Low-cost Visual Tracking with an Intelligent Wheelchair for Innovative Assistive Care', 2012 12TH INTERNATIONAL CONFERENCE ON CONTROL, AUTOMATION, ROBOTICS & VISION (ICARCV), International Conference on Control, Automation, Robotics and Vision, IEEE, Guangzhou, China, pp. 1540-1545.
View/Download from: Publisher's site
View description>>
This paper presents the development of a low-cost vision-based robotic wheelchair system towards autonomous convoying. The non-holonomic follower vehicle obtains visual real-time pose data of a known coplanar target installed on the back of the leading vehicle. This allows the tracking vehicle to mimic the path of the preceding vehicle, while maintaining a safe distance behind it with the aid of a controller based on the robot's kinematics constraints. A back-end visual filter is proposed in the planning strategy to overcome the noisy environmental information acquired from the camera as it tracks the vehicle in front. The effectiveness of the approach is evaluated in an indoor setting using data obtained from an instrumented wheelchair platform and a low-cost camera, and validated with observations from a laser range finder and derived (known) maps of the environment. © 2012 IEEE.
Nguyen, LV, Kodagoda, S, Ranasinghe, R, Dissanayake, G & IEEE 1970, 'Simulated Annealing Based Approach for Near-Optimal Sensor Selection in Gaussian Processes', 2012 INTERNATIONAL CONFERENCE ON CONTROL, AUTOMATION AND INFORMATION SCIENCES (ICCAIS), International Conference on Control, Automation and Information Sciences, IEEE, Ho Chi Minh City, Vietnam, pp. 142-147.
View/Download from: Publisher's site
View description>>
This paper addresses the sensor selection problem associated with monitoring spatial phenomena, where a subset of k sensor measurements from among a set of n potential sensor measurements is to be chosen such that the root mean square prediction error is minimised. It is proposed that the spatial phenomena to be monitored is modelled using a Gaussian Process and a simulated annealing based approximately heuristic algorithm is used to solve the resulting minimisation problem. The algorithm is shown to be computationally efficient and is illustrated using both indoor and outdoor environment monitoring scenarios. It is shown that, although the proposed algorithm is not guaranteed to find the optimum, it always provides accurate solutions for broad range real-world and computer generated datasets.
Norouzi, M, De Bruijn, F & Miró, JV 1970, 'Planning Stable Paths for Urban Search and Rescue Robots', Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), Robot Soccer World Cup, Springer Berlin Heidelberg, Istanbul, Turkey, pp. 90-101.
View/Download from: Publisher's site
View description>>
Rescue robots are platforms designed to operate in challenging and uneven surfaces. These robots are often equipped with manipulator arms and varying traction arrangements. As such, it is possible to reconfigure the kinematic of robot in order to reduce potential instabilities, such as those leading to vehicle tip-over. This paper proposes a methodology to plan feasible paths through uneven topographies by planning stable paths that account for the safe interaction between vehicle and terrain. The proposed technique, based on a gradient stability criterion, is validated with two of the best known path search strategies in 3D lattices, i.e. the A* and the Rapidly-Exploring Random Trees. Using real terrain data, simulation results obtained with the model of a real rescue robot demonstrate significant improvements in terms of paths that are able to automatically avoid regions of potential instabilities, to concentrate on those where the freedom of exploiting posture adaptation permits generation of optimally safe paths. © 2012 Springer-Verlag Berlin Heidelberg.
Norouzi, M, Miro, JV, Dissanayake, G, IEEE & Japan, RSO 1970, 'Planning High-Visibility Stable Paths for Reconfigurable Robots On Uneven Terrain', 2012 IEEE/RSJ INTERNATIONAL CONFERENCE ON INTELLIGENT ROBOTS AND SYSTEMS (IROS), IEEE/RSJ International Conference on Intelligent Robots and Systems, IEEE, Algarve, Portugal, pp. 2844-2849.
View/Download from: Publisher's site
View description>>
This paper proposes a motion planning strategy for reconfigurable mobile robots in uneven terrain. Paths that guarantee stability while at the same time maximise the height of the sensor payload, thereby enhancing the capacity of the robot to explore the environment are obtained using a search algorithm based on A*. This is particularly applicable to operations such as search and rescue where observing the environment for locating victims is the major objective, although the proposed technique can be generalised to incorporate other potentially conflicting objectives such as minimising energy. The proposed planning strategy looks at exploiting the (possibly incomplete) environment information available to the robot and/or operator as it explores novel terrain. The effectiveness of the approach is evaluated using data obtained from a multi-tracked robot fitted with a manipulator arm and a range camera in a mock-up search and rescue arena. © 2012 IEEE.
Pagano, D, Liu, D, Waldron, K & IEEE 1970, 'A Method for Optimal Design of an Inchworm Climbing Robot', 2012 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND BIOMIMETICS (ROBIO 2012), IEEE International Conference on Robotics and Biomimetics, IEEE, Guangzhou, China, pp. 1293-1298.
View/Download from: Publisher's site
View description>>
Many ferromagnetic structures require regular inspection and maintenance to ensure their longevity, structural integrity and aesthetics. These operations are often very hazardous to workers, as they are normally performed at height or in confined spaces, and can expose workers to hazardous materials such as lead based paints and vehicle fumes. An inchworm climbing robot has been proposed as a solution that would improve the quality of the inspection procedure and the occupational health and safety for the maintenance personnel while reducing setup times and costs. However, a number of challenges in designing such an inchworm robot arise from the environmental, mobility and safety factors. This paper describes these challenges for given design applications and presents a method to optimise the design to address the challenges. Analyses of the results attest to the feasibility of the solution. © 2012 IEEE.
Patel, M, Miro, JV & Dissanayake, G 1970, 'A Hierarchical Hidden Markov Model to Support Activities of Daily Living with an Assistive Robotic Walker', 2012 4TH IEEE RAS & EMBS INTERNATIONAL CONFERENCE ON BIOMEDICAL ROBOTICS AND BIOMECHATRONICS (BIOROB), IEEE RAS/EMBS International Conference on Biomedical and Biomechatronics, IEEE RAS/EMBS International Conference on Biomedical and Biomechatronics, Rome, Italy, pp. 1071-1076.
View/Download from: Publisher's site
View description>>
This paper proposes a Hierarchical Hidden Markov Model (HHMM) framework as the most suitable tool to exploit the interactions between an intelligent mobility aid and their human operator. The framework presented is capable of learning a mixed array of the Activities of Daily Living (ADL) that the typical user of these supportive devices would normally engage in, both navigational and non-navigational in nature, and provide assistance as and when required. The main contribution of this paper is the demonstration of how this probabilistic tool capable of modelling behaviours at multiple levels of abstraction is a natural embodiment of machine intelligence to support user activities. Effectiveness of the proposed HHMM framework is evaluated with a number of healthy volunteers using a conventional rolling walker equipped with sensing and navigational aids whilst operating in a structured environment resembling a home. A comparison with more traditional discriminative models and mixed generative-discriminative models is also presented to provide a complete picture that highlights the benefits of the proposed approach. © 2012 IEEE.
Qayyum, U & Kim, J 1970, 'Global optimal solution to SLAM problem with unknown initial estimates', ICINCO 2012 - Proceedings of the 9th International Conference on Informatics in Control, Automation and Robotics, pp. 76-83.
View description>>
The paper presents a practical approach for finding the globally optimal solution to SLAM. Traditional methods are based upon local optimization based strategies and are highly susceptible to local minima due to non-convex nature of the SLAM problem. We employed the nonlinear global optimization based approach to SLAM by exploiting the theoretical limit on the numbers of local minima. Our work is not reliant on good initial guess, whereas existing approaches in SLAM literature assume good starting point to avoid local minima problem. The paper presents experimental results on different datasets to validate the robustness of the approach, finding the global basin of attraction with unknown initial guess. Copyright © 2012 SciTePress.
Qayyum, U & Kim, J 1970, 'Seamless aiding of inertial-slam using Visual Directional Constraints from a monocular vision', 2012 IEEE/RSJ International Conference on Intelligent Robots and Systems, 2012 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS 2012), IEEE, IEEE, pp. 4205-4210.
View/Download from: Publisher's site
Sankaran, S & Agarwal, R 1970, 'Rethinking project management goals and methods to suit service systems', 56th Annual Meeting of the International Society for the Systems Sciences 2012, ISSS 2012: Service Systems, Natural Systems, International Conference on Service Systems and Service Management, ISSS, San Jose, CA, USA, pp. 704-717.
View description>>
Industrial economies of the past are now moving towards becoming service-intensive, creative and knowledge-based economies that incorporate human creativity and social capital as the basis of value creation and productivity improvements. Moreover, they are radically transforming the manner in which they design, deliver and operate, thereby creating new services and market opportunities. Further, the fact that services are varied, have unique attributes - such as intangibility, heterogeneity, perishability, and inseparability (simultaneous consumption and delivery) - with the customer as a provider of input, make them complex in nature and difficult to understand and analyse. This has inspired a flurry of activity in government, industry and universities. There is now a growing recognition of the need for transdisciplinary research and new business models to propel innovation in services, commonly referred to as Services Science - An interdisciplinary cross-functional stream that brings together engineering, social sciences and management. In addition, business success is becoming less associated with tangible outcomes, embedded value and physical transactions, but more reliant on intangible resources, relationships, networks and co-creation of value. In the unfolding global economy, supply chains and value networks play a crucial role, and service organisations have to find innovative ways for attaining sustainable competitive advantage. Beyond this direct economic contribution, service industries have an ongoing role to deliver considerable indirect embodied value to goods production. Transformations in organisational structures and relations can imply changes in some or all of the mechanisms used to govern projects. Moreover, there is a growing consensus that project managers have to be more strategically instrumental than before in transforming organisational practices and processes when accomplishing project objectives. Underpinned by changing dynam...
Sankaran, S, Cameron, R & Scales, J 1970, 'The utility and quality of mixed methods in Project Management Research', EURAM 12th Annual Conference 2012, Annual Conference of the European Academy of Management, EURAM, Erasmus University, Rotterdam.
View description>>
Mixed methods research is being touted as the third methodological movement which is characterised by a growing body of theoretical and methodological frameworks and a body of cross disciplinary literature. Prominent mixed methodologists/authorities have championed the movement, which has strong footholds in the fields of education, health and nursing, and the social and behavioural sciences. The establishment of mixed method specific journals, research texts and courses and a growth in popularity among research funding bodies all indicate the growing trend in the adoption of mixed methods. Mixed methods research is being used and reported within business and management fields, despite the positivist traditions attached to certain business and management disciplines. This paper has used a retrospective content analysis of journal articles from three ranked journals from the field of project management: International Journal of Project Management (IJPM), the Project Management Journal (PMJ) and the IEEE Transactions on Engineering Management (IEEE_TEM). The aim of the study is to determine the prevalence rates of mixed methods in project management and to investigate the quality of mixed methods research within this field. Implications for further research are discussed, along with some guidelines to justify and describe how mixed methods have been used in project management research papers.
Shi, L, Kodagoda, S, Dissanayake, G, IEEE & Japan, RSO 1970, 'Application of Semi-supervised Learning with Voronoi Graph for Place Classification', 2012 IEEE/RSJ INTERNATIONAL CONFERENCE ON INTELLIGENT ROBOTS AND SYSTEMS (IROS), IEEE/RSJ International Conference on Intelligent Robots and Systems, IEEE, Vilamoura, Algarve, Portugal, pp. 2991-2996.
View/Download from: Publisher's site
View description>>
Representation of spaces including both geometric and semantic information enables a robot to perform high-level tasks in complex environments. Therefore, in recent years identifying and semantically labeling the environments based on onboard sensors has become an important competency for mobile robots. Supervised learning algorithms have been extensively used for this purpose with SVM-based solutions showing good generalization properties. The CRF-based approaches take the advantage of connectivity information of samples thereby provide a mechanism to capture complex dependencies. Blending the complementary strengths of Support Vector Machine (SVM) and Conditional Random Field (CRF), there have been algorithms to exploit the advantages of both to enhance the overall accuracy of place classification in indoor environments. However, experiments show that none of the above approaches deal well with diversified testing data. In this paper, we focus mainly on the generalization ability of the model and propose a semi-supervised learning strategy, which essentially improves the performance of the system. Experiments have been carried out on six real-world maps from different universities around the world and the results from rigorous testing demonstrate the feasibility of the approach.
Shi, L, Kodagoda, S, Khushaba, R, Dissanayake, G & IEEE 1970, 'Application of CRF and SVM based Semi-supervised Learning for Semantic Labeling of Environments', 2012 12TH INTERNATIONAL CONFERENCE ON CONTROL, AUTOMATION, ROBOTICS & VISION (ICARCV), International Conference on Control, Automation, Robotics and Vision, IEEE, Guangzhou, pp. 835-840.
View/Download from: Publisher's site
View description>>
Understanding the environment in both geometric and semantic levels enables a robot to perform high-level tasks in complex environments. Therefore in recent years research towards identifying and semantically labeling the environments based on onboard sensors for mobile robots has been gaining popularity. After the era of heuristic and rule-based approaches, supervised learning algorithms like Support Vector Machines (SVM) and AdaBoost have been extensively used for this purpose showing satisfactory performance. With the introduction of graphical models, approaches like Conditional Random Fields (CRF) which take the advantage of connectivity of samples provide more flexibility to capture complex dependencies. In this paper, we focus on a real-world task which challenges the generalization ability of the model, evaluate some graph based features, propose a semi-supervised learning algorithm by iteratively utilizing the results from SVM and CRF, and suggest a solution for CRF parameter estimation with partially labeled training data. Experiments have been conducted on six realworld indoor environments demonstrating the competence of the algorithm.
Tang, R & Liu, D 1970, 'An enhanced dynamic model for McKibben pneumatic muscle actuators', Australasian Conference on Robotics and Automation, ACRA.
View description>>
An enhanced dynamic force model of a type of small and soft McKibben-type pneumatic muscle (PM) actuator has been developed. This model takes the factor of external loads and a more sophisticated form of friction into account, and is presented as a polynomial function of pressure, contraction length, contraction velocity and external load. The coefficients in this model are determined from a series of experiments with constant loads and step pressure inputs. Comparison study with other models is conducted assuming the Coulomb friction as a constant force. The results demonstrate a solid enhancement of the presented model.
To, AW-K, Paul, G, Rushton-Smith, D, Liu, D & Dissanayake, G 1970, 'Automated and Frequent Calibration of a Robot Manipulator-mounted IR Range Camera for Steel Bridge Maintenance.', FSR, International Conference on Field and Service Robotics, Springer, Matsushima, Miyagi, Japan, pp. 205-218.
View/Download from: Publisher's site
View description>>
This paper presents an approach to perform frequent hand-eye calibration of an Infrared (IR) range camera mounted to the end-effector of a robot manipulator in a field environment. A set of three reflector discs arranged in a structured pattern is attached to the robot platform to provide high contrast image features with corresponding range readings for accurate calculation of the camera-to-robot base transform. Using this approach the hand-eye transform between the IR range camera and robot end-effector can be determined by considering the robot manipulator model. Experimental results show that a structured lighting-based IR range camera can be reliably hand-eye calibrated to a six DOF robot manipulator using the presented automated approach. Once calibrated, the IR range camera can be positioned with the manipulator so as to generate a high resolution geometric map of the surrounding environment suitable for performing the grit-blasting task. © Springer-Verlag Berlin Heidelberg 2014.
Valencia, R, Miro, JV, Dissanayake, G, Andrade-Cetto, J, IEEE & Japan, RSO 1970, 'Active Pose SLAM', 2012 IEEE/RSJ INTERNATIONAL CONFERENCE ON INTELLIGENT ROBOTS AND SYSTEMS (IROS), IEEE/RSJ International Conference on Intelligent Robots and Systems, IEEE, Algarve, Portugal, pp. 1885-1891.
View/Download from: Publisher's site
View description>>
We present an active exploration strategy that complements Pose SLAM [1] and optimal navigation in Pose SLAM [2]. The method evaluates the utility of exploratory and place revisiting sequences and chooses the one that minimizes overall map and path entropies. The technique considers trajectories of similar path length taking marginal pose uncertainties into account. An advantage of the proposed strategy with respect to competing approaches is that to evaluate information gain over the map, only a very coarse prior map estimate needs to be computed. Its coarseness is independent and does not jeopardize the Pose SLAM estimate. Moreover, a replanning scheme is devised to detect significant localization improvement during path execution. The approach is tested in simulations in a common publicly available dataset comparing favorably against frontier based exploration. © 2012 IEEE.
Van Nguyen, L, Ranasinghe, R, Kodagoda, S & Dissanayake, G 1970, 'Sensor selection based routing for monitoring Gaussian processes modeled spatial phenomena', Australasian Conference on Robotics and Automation, ACRA, Australasian Conference on Robotics and Automation, The ACRA 2012 Organising Committee, Wellington, New Zealand, pp. 1-7.
View description>>
This paper addresses the trade-off between the sensing quality and the energy consumption in the wireless sensor network associated with monitoring spatial phenomena. We use a non-parametric Gaussian Process to model the spatial phenomena to be monitored and simulated annealing based approximately heuristic algorithm for sensor selection. Our novel Sensor Selection based Routing (SSR) algorithm uses this model to identify the most informative nodes, which gives the root mean square prediction error less than a specified threshold, to construct the minimal energy-expended routing tree rooted at the sink. Our experiments have verified that the proposed computationally efficient SSR algorithm has significant advantages over conventional techniques.
Vidal-Calleja, TA & Agammenoni, G 1970, 'Integrated probabilistic generative model for detecting smoke on visual images', 2012 IEEE International Conference on Robotics and Automation, 2012 IEEE International Conference on Robotics and Automation (ICRA), IEEE, St Paul, MN, pp. 2183-2188.
View/Download from: Publisher's site
View description>>
Early fire detection is crucial to minimise damage and save lives. Video surveillance smoke detectors do not suffer from transport delays and can cover large areas. The smoke detection on images is, however, a difficult problem due the variability of smoke density, lighting conditions, background clutter, and unstable patterns. In order to solve this problem, we propose a novel unsupervised object classifier. Single visual features are classified using a model that simultaneously creates a codebook and categorises the smoke using a bag-of-words paradigm based on LDA model. Our algorithm can also tell the amount of smoke present on the image. Multiple image sequences from different cameras are used to show the viability of the proposed approach. Our experiments show that the model generalises well for different cameras, perspectives and scales. © 2012 IEEE.
Wang, H, Hu, G, Huang, S & Dissanayake, G 1970, 'On the Structure of Nonlinearities in Pose Graph', Robotics: Science and Systems VIII, Robotics: Science and Systems 2012, Robotics: Science and Systems Foundation, Sydney, Australia, pp. 1-8.
View/Download from: Publisher's site
View description>>
Pose graphs have become an attractive representation for solving Simultaneous Localization and Mapping (SLAM) problems. In this paper, we analyze the structure of the nonlinearities in the 2D SLAM problem formulated as the optimizing of a pose graph. First, we prove that finding the optimal configuration of a very basic pose graph with 3 nodes (poses) and 3 edges (relative pose constraints) with spherical covariance matrices, which can be formulated as a six dimensional least squares optimization problem, is equivalent to solving a one dimensional optimization problem. Then we show that the same result can be extended to the optimizing of a pose graph with two anchor nodes where every edge is connecting to one of the two anchor nodes. Furthermore, we prove that the global minimum of the resulting one dimensional optimization problem must belong to a certain interval and there are at most 3 minima in that interval. Thus the globally optimal pose configuration of the pose graph can be obtained very easily through the bisection method and closed-form formulas.
Wang, S, Khushaba, R & Kodagoda, S 1970, 'Towards speed-independent road-type classification', 2012 12th International Conference on Control Automation Robotics & Vision (ICARCV), 2012 12th International Conference on Control Automation Robotics & Vision (ICARCV 2012), IEEE, Guangzhou, CHina, pp. 614-619.
View/Download from: Publisher's site
View description>>
The knowledge of terrain types is not only useful for improving passenger's safety and comfort, but also for bounding safe navigation routes for autonomous vehicles. Most of the work in the literature is limited to rover operations at slower speeds or rovers with rigid wheels. This paper discusses and presents a critical analysis of speed independency of classifiers for passenger vehicles with tyres at road operating speeds. The suitability of using different features calculated based on vertically mounted accelerometer data as well as road profile data were analyzed. The experimental results agree with the literature, where speed independency could be achieved by using the Fast Fourier Transform (FFT) features extracted from the estimated road profiles. However, we also show that it is possible to achieve comparable results by extracting different features directly from acceleration data. This eliminates the requirement of accurate knowledge of the vehicle model parameters or speed of the vehicle. © 2012 IEEE.
Wang, S, Kodagoda, S & Ranasinghe, R 1970, 'Road terrain type classification based on laser measurement system data', Australasian Conference on Robotics and Automation, ACRA, Australasian Conference on Robotics and Automation, ARAA, Wellington, New Zealand, pp. 1-6.
View description>>
For road vehicles, knowledge of terrain types is useful in improving passenger safety and comfort. The conventional methods are susceptible to vehicle speed variations and in this paper we present a method of using Laser Measurement System (LMS) data for speed independent road type classification. Experiments were carried out with an instrumented road vehicle (CRUISE), by manually driving on a variety of road terrain types namely Asphalt, Concrete, Grass, and Gravel roads at different speeds. A looking down LMS is used for capturing the terrain data. The range data is capable of capturing the structural differences while the remission values are used to observe anomalies in surface reflectance properties. Both measurements are combined and used in a Support Vector Machines Classifier to achieve an average accuracy of 95% on different road types.
Wang, S, Kodagoda, S, Li, H & Shi, L 1970, 'Road Type Recognition Based on Vibration and Image Classification', PROCEEDINGS OF THE FIRST INTERNATIONAL CONFERENCE ON MECHATRONIC SYSTEM AND MEASUREMENT TECHNOLOGY, 1st International Conference on Mechatronic System and Measurement Technology, SCIENCE PRESS USA INC, Nanjing, PEOPLES R CHINA, pp. 70-78.
Wang, Z, Dissanayake, G & IEEE 1970, 'Exploiting Vehicle Motion Information in Monocular SLAM', 2012 12TH INTERNATIONAL CONFERENCE ON CONTROL, AUTOMATION, ROBOTICS & VISION (ICARCV), International Conference onControl Automation Robotics & Vision (ICARCV), IEEE, Guangzhou, China, pp. 1030-1035.
View/Download from: Publisher's site
View description>>
It is now well known that increasing the number of features maintained in the mapping process of the monocular SLAM improves the accuracy of the outcome. This, however, increases the state dimension and the associated computational cost. This paper investigates and evaluates the improvement on SLAM results by exploiting camera motion information. For a camera mounted on a vehicle, its motion is subject to the vehicle motion model. The work of this paper shows that by introducing relative pose constraints calculated from image points by considering the underlying vehicle motion model (for example the non-holonomic vehicle motion model), it is possible to incorporate vehicle motion information into the system and achieve even more accurate SLAM results than maintaining all extracted features in the map. It is demonstrated that in this process, the state dimension is not increased, and the sparse structure of the SLAM problem is maintained. So the underlying sparseness in the SLAM problem structure can still be exploited for computational efficiency. Simulation and experiment results are presented to demonstrate the relative merits of incorporating vehicle motion information for motion estimation and mapping.
Ward, P & Liu, D 1970, 'Design of a high capacity Electro Permanent Magnetic adhesion for climbing robots', 2012 IEEE International Conference on Robotics and Biomimetics (ROBIO), 2012 IEEE International Conference on Robotics and Biomimetics (ROBIO), IEEE, Guangzhou, China, pp. 217-222.
View/Download from: Publisher's site
View description>>
The interest for robotic solutions to perform inspection and maintenance of steel structures is realised with reduced costs, improved safety and improved efficiency. However current robotic solutions are limited by the required adhesion to support the robot and payload device. The design of an Electro Permanent Magnetic device is studied to yield a high capacity adhesion method for use with industrial climbing robots. The adhesion device must provide a lightweight, low power and a failsafe solution for ferromagnetic surfaces. The design process to achieve maximum holding force for Electro Permanent Magnets is presented. © 2012 IEEE.
Xu, Z, Fitch, R, Sukkarieh, S & IEEE 1970, 'Learning Utility Models for Decentralised Coordinated Target Tracking', 2012 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION (ICRA), IEEE International Conference on Robotics and Automation, IEEE, Saint Paul, MN, USA, pp. 1753-1759.
View/Download from: Publisher's site
View description>>
In decentralised target tracking, a set of sensors observes moving targets. When the sensors are static but steerable, each sensor must dynamically choose which target to observe in a decentralised manner. We show that the information exchanged by the sensors to synchronise their beliefs can be exploited to learn a model of the utility function that drives each others' decisions. Instead of communicating utilities to enable negotiation, each sensor regresses on the learnt model to predict the utilities of other team members. This approach bridges the gap between coordinating implicitly, a locally-greedy solution, and negotiating explicitly. We validated our approach in both hardware and simulations, and found that it out-performed implicit coordination by a statistically significant margin with both ideal and limited communications. © 2012 IEEE.
Zainudin, Z, Kodagoda, S & Van Nguyen, L 1970, 'Mutual information based data selection in Gaussian processes for people tracking', Australasian Conference on Robotics and Automation, ACRA, Australasian Conference on Robotics and Automation, The ACRA 2012 Organising Committee, Wellington, New Zealand, pp. 1-6.
View description>>
It is the general perception that models describing human motion patterns enhance tracking even with long term occlusions. One effective way of learning such patterns is to use Gaussian Processes (GP). However, with the increase of the amount of training data with time, the GP becomes computationally intractable. In this work, we have proposed a Mutual Information (MI) based technique along with the Mahalanobis Distance (MD) measure to keep the most informative data while discarding the least informative data. The algorithm is tested with data collected in an office environment with a Segway robot equipped with a laser range finder. It leads to more than 80% data reduction while keeping the rms errors within the required bounds. We have also implemented a GP based Particle filter tracker for long term people tracking with occlusions. The comparison results with Extended Kalman Filter based tracker shows the superiority of the proposed approach.
Zhang, WD, Robinson, C, Zheng, XF & Zhang, JF 1970, 'Characterisation of electron traps in high-k dielectric stacks for Flash memory applications using fast pulse techniques', 2012 IEEE 11th International Conference on Solid-State and Integrated Circuit Technology, 2012 IEEE 11th International Conference on Solid-State and Integrated Circuit Technology (ICSICT), IEEE, Xian, PEOPLES R CHINA, pp. 1-4.
View/Download from: Publisher's site
