Clark, S & Dissanayake, G 1999, 'Simultaneous localisation and map building using millimetre wave radar to extract natural features', Proceedings - IEEE International Conference on Robotics and Automation, vol. 2, pp. 1316-1321.
View description>>
This paper discusses the use of a 77GHz millimetre wave radar as a guidance sensor for autonomous land vehicle navigation. An extended Kalman filter (EKF) maintains an estimate of map features in addition to vehicle state. This map augmented EKF is implemented with radar reflectors, designed for high visibility from all orientations. An improvement on this approach enables natural features to be identified, using the polarisation of returned radar signals. Those that are suitable as navigational markers are used to update estimates of vehicle and feature locations. This method requires no a priori knowledge of the environment and no target infrastructure.
Dissanayake, G, Sukkarieh, S, Nebot, E & Durrant-Whyte, H 1999, 'New algorithm for the alignment of inertial measurement units without external observation for land vehicle applications', Proceedings - IEEE International Conference on Robotics and Automation, vol. 3, pp. 2274-2279.
View description>>
This paper describes a real time, on-the-fly, Roll and Pitch alignment algorithm for Inertial Measurement Units (IMUs) mounted on land vehicles. Unlike conventional strategies, the alignment is achieved without external observations. This is achieved by exploiting the non-holonomic constraints that govern the motion of a vehicle on a surface to obtain the Roll and Pitch of the IMU. The position of the vehicle along its path is still unobservable and the algorithm is effective only when there is sufficient excitation in all degrees of freedom. However, with the proposed alignment algorithm, the IMU is able to provide sufficiently accurate position information for substantially longer periods of time compared with conventional methods. Experimental results are provided along with a comparison of an IMU/GPS navigation loop showing the effectiveness of the algorithm.
Fang, JQ, Li, QS & Liu, DK 1999, 'Non-spillover control design of tall buildings in modal space', Wind and Structures, vol. 2, no. 3, pp. 189-200.
View/Download from: Publisher's site
View description>>
In this paper, a new algorithm for active control design of structures is proposed and investigated. The algorithm preserves the decoupling property of the modal vibration equation and eliminates the spillover problem, which is the main shortcoming in the independent modal space control (IMSC) algorithm. With linear quadratic regulator(LQR) control law, the analytical solution of algebraic Riccati equation and the optimal actuator control force are obtained, and the control design procedure is significantly simplified. A numerical example for the control design of a tall building subjected to wind loads demonstrates the effectiveness of the proposed algorithm in reducing the acceleration and displacement responses of tall buildings under wind actions.
Fang, JQ, Li, QS, Jeary, AP & Liu, DK 1999, 'Damping of tall buildings: its evaluation and probabilistic characteristics', The Structural Design of Tall Buildings, vol. 8, no. 2, pp. 145-153.
View/Download from: Publisher's site
Fang, JQ, Li, QS, Jeary, AP, Liu, DK & Wong, CK 1999, 'Probabilistic characteristics of damping in buildings', Wind and Structures, vol. 2, no. 2, pp. 127-131.
View/Download from: Publisher's site
View description>>
This paper describes probabilistic characteristics of damping in a tall building based on the results of full-scale measurement. It is found, through statistical analysis of the damping data, that the probability density function(PDF) of damping at the high amplitude plateau can be well represented by Normal distribution (Gaussian distribution). A stochastic damping model is proposed to estimate amplitude-dependent damping for practical application.
Huang, S & Zhang, S 1999, 'Some control problems for symmetric circulant composite systems', Kongzhi Lilun Yu Yingyong/Control Theory and Applications, vol. 16, no. 4.
View description>>
In this paper, we study the output regulation for symmetric circulant composite systems and the quadratic stability and the quadratic stabilization for uncertain symmetric circulant omposite systems. It is shown that because of the special structure of the system, the output regulator roblems for such a system can be transfered to the output regulator problem for sys tems with lower rder. The quadratic stability for such a system can be simplified by considering the quadratic stability of several independent systems of lower order. And the quadratic stabilization controller of such a system can be constructed by the quadratic stabilization controller of systems with lower order.
Huang, S, Zheng, L, Yang, G-H & Zhang, S 1999, 'The decoupling of a class of large-scale systems with symmetric circulant structure', IFAC Proceedings Volumes, vol. 32, no. 2, pp. 5903-5908.
View/Download from: Publisher's site
Kim, J, Moon, SW, Kim, SH, Hwang, DH, Lee, SJ, Oh, MS & and Ra, SW 1999, 'Design of a loosely-coupled GPS/INS integration system', Journal of the Korea Institute of Military Science and Technology, vol. 2, pp. 186–196-186–196.
Li, Q, Cao, H, Li, G, Li, S & Liu, D 1999, 'Optimal design of wind-induced vibration control of tall buildings and high-rise structures', Wind and Structures, vol. 2, no. 1, pp. 69-83.
View/Download from: Publisher's site
View description>>
The most common used control device on tall buildings and high-rise structures is active and passive tuned mass damper (ATMD and TMD). The major advantages of ATMD and TMD are discussed. The existing installations of various passive/active control devices on real structures are listed. A set of parameter optimization methods is proposed to determine optimal parameters of passive tuned mass dampers under wind excitation. Simplified formulas for determining the optimal parameters are proposed so that the design of a TMD can be carried out easily. Optimal design of wind-induced vibration control of frame structures is investigated. A thirty-story tall building is used as an example to demonstrate the procedure and to verify the efficiency of ATMD and TMD with the optimal parameters.
Li, QS, Fang, JQ & Liu, DK 1999, 'Evaluation of structural dynamic responses by stochastic finite element method', Structural Engineering and Mechanics, vol. 8, no. 5, pp. 477-490.
View/Download from: Publisher's site
Li, QS, Liu, DK & Fang, JQ 1999, 'Optimum Design of Actively Controlled Structures Using Genetic Algorithms', Advances in Structural Engineering, vol. 2, no. 2, pp. 109-118.
View/Download from: Publisher's site
View description>>
Optimal placement of actuators in actively controlled structures is a mixed-discrete optimization problem; it has the characteristics of nonlinear, non-continuous, and so on. For this type of optimization problem, traditional optimization methods based on mathematical programming may not be effective. In this paper, the complexity, discreteness and non-linearity of the optimal design problems of actuator placement are investigated. An optimal control algorithm and active tendon controllers are applied to control the response of a 16-storey building under earthquake loads. A mathematical model of optimal actuator configuration is established. Based on the special optimization problem of actuator configuration in an actively controlled structure, a modified genetic algorithm is presented and applied to solve the problems. A design procedure/method is presented for this kind of optimization problem, and the suitability of this method for the optimization problem is investigated. The numerical calculation and analysis are carried out for the building controlled by active tendon control mechanisms, and the results are discussed and analyzed in detail.
Li, QS, Liu, DK, Fang, JQ, Jeary, AP & Wong, CK 1999, 'Using neural networks to model and predict amplitude dependent damping in buildings', Wind and Structures, vol. 2, no. 1, pp. 25-40.
View/Download from: Publisher's site
View description>>
In this paper, artificial neural networks, a new kind of intelligent method, are employed to model and predict amplitude dependent damping in buildings based on our full-scale measurements of buildings. The modelling method and procedure using neural networks to model the damping are studied. Comparative analysis of different neural network models of damping, which includes multi-layer perception network (MLP), recurrent neural network, and general regression neural network (GRNN), is performed and discussed in detail. The performances of the models are evaluated and discussed by tests and predictions including self-test, `one-lag' prediction and `multi-lag' prediction of the damping values at high amplitude levels. The established models of damping are used to predict the damping in the following three ways: (1) the model is established by part of the data measured from one building and is used to predict the another part of damping values which are always difficult to obtain from field measurements: the values at the high amplitude level. (2) The model is established by the damping data measured from one building and is used to predict the variation curve of damping for another building. And (3) the model is established by the data measured from more than one buildings and is used to predict the variation curve of damping for another building. The prediction results are discussed.
Scheding, S, Dissanayake, G, Nebot, EM & Durrant-Whyte, H 1999, 'An experiment in autonomous navigation of an underground mining vehicle', IEEE TRANSACTIONS ON ROBOTICS AND AUTOMATION, vol. 15, no. 1, pp. 85-95.
View/Download from: Publisher's site
View description>>
This paper describes the theoretical development and experimental evaluation of a navigation system for an autonomous load, haul, and dump truck (LHD) based on the results obtained during extensive in-situ field trials. The particular contributions of th
Schmiedeler, JP & Waldron, KJ 1999, 'The Mechanics of Quadrupedal Galloping and the Future of Legged Vehicles', The International Journal of Robotics Research, vol. 18, no. 12, pp. 1224-1234.
View/Download from: Publisher's site
View description>>
Previous studies have noted that biological quadrupeds adjust their gaits when encountering drag in their locomotion. This paper investigates the hypothesis that these gait adjustments allow the legs to operate at an optimal working length when generating thrust. A 5-DoF dynamic model of a quadruped having a rigid trunk and massless legs is formulated. This model reflects the dimensions and inertial properties of a galloping machine the authors are designing. The constrained, steady-state motion equations governing the transverse and rotary gallops of the model are solved numerically for various levels of drag. The footfall phasing solutions for both forms of the gallop approach a partially in-phase gait, the half-bound, as drag increases. These gait transitions are the result of constraints requiring the legs to operate at their optimal working length when in contact with the terrain. Thus, the behavior of the model supports the original hypothesis. This paper also includes a discussion of future research directions in the field of artificial legged locomotion.
Shoudong Huang, Lam, J, Guang-Hong Yang & Siying Zhang 1999, 'Fault tolerant decentralized H/sub ∞/ control for symmetric composite systems', IEEE Transactions on Automatic Control, vol. 44, no. 11, pp. 2108-2114.
View/Download from: Publisher's site
Wijesoma, WS, Kodagoda, KRS & Teoh, EK 1999, 'Un-coupled fuzzy controller for longitudinal and lateral control of a golf car-like AGV', IEEE Conference on Intelligent Transportation Systems, Proceedings, ITSC, pp. 142-147.
View description>>
The development of techniques for lateral and longitudinal control of vehicles has become an important and active research topic in the face of emerging markets for advanced AGVs and mobile robots. The primary focus is on the development of an intelligent control scheme, which is insensitive to parametric uncertainty, load and parameter fluctuations and most importantly amenable to real time implementation. We have reviewed promising control schemes for steering and speed control of mobile robots. In this paper, we present an effective uncoupled direct fuzzy PD/PI control scheme for a particular outdoor AGV, which is a converted electrically powered golf-car. The controller performance is assessed against the required performance criteria and another nonlinear technique, viz. the computed torque technique (CTT).
Kodagoda, KRS, Wijesoma, WS & Teoh, EK 1970, 'Robust Un-coupled Fuzzy Controller for Longitudinal and Lateral Control of an AGV', Lecture Notes in Computer Science 1625, International Conference on Computational Intelligence, Theory and Applications, Springer Berlin Heidelberg, Germany, pp. 370-381.
View/Download from: Publisher's site
Moon, SW, Kim, J, Hwang, D, Ra, S & Lee, SJ 1970, 'Implementation of a Loosely-Coupled GPS/INS Integration System', Proc. of The 4th International Symposium on Satellite Navigation Technology and Applications, Brisbane, Queensland, Australia.
Wijesoma, WS & Kodagoda, KRS 1970, 'Synthesis of Stable Fuzzy PD/PID Control Laws for Robotic Manipulators from a Variable Structure Systems Standpoint', Lecture Notes in Computer Science 1625, International Conference on Computational Intelligence, Theory and Applications,, Springer Berlin Heidelberg, Germany, pp. 495-511.
View/Download from: Publisher's site
