Wavefront Propagation and Fuzzy based Autonomous Navigation, Page 093-102
Adel Al-Jumaily & Cindy Leung, Mechatronics and Intelligent Systems Group,Faculty of Engineering, University of Technology, Sydney, Australia

Abstract: Path planning and obstacle avoidance are the two major issues in any navigation system. Wavefront propagation algorithm, as a good path planner, can be used to determine an optimal path. Obstacle avoidance can be achieved using possibility theory. Combining these two functions enable a robot to autonomously navigate to its destination. This paper presents the approach and results in implementing an autonomous navigation system for an indoor mobile robot. The system developed is based on a laser sensor used to retrieve data to update a two dimensional world model of therobot environment. Waypoints in the path are incorporated into the obstacle avoidance. Features such as ageing of objects and smooth motion planning are implemented to enhance efficiency and also to cater for dynamic environments.
Keywords: possibility theory, wavefront propagation, autonomous robot, indoor environment

Control of a Lightweight Flexible Robotic Arm Using Sliding Modes, Page 103-110
Victor Etxebarria; Arantza Sanz & Ibone Lizarrag, Dpto. de Electricidad y Electrónica, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Bilbao, Spain

Abstract: This paper presents a robust control scheme for flexible link robotic manipulators, which is based on considering the flexible mechanical structure as a system with slow (rigid) and fast (flexible) modes that can be controlled separately. The rigid dynamics is controlled by means of a robust sliding-mode approach with well-established stability properties while an LQR optimal design is adopted for the flexible dynamics. Experimental results show that this composite approach achieves good closed loop tracking properties both for the rigid and the flexible dynamics.
Keywords: sliding control, robot manipulators, flexible robotic arms, robust control

A Hybrid Three Layer Architecture for Fire Agent Management in Rescue Simulation Environment, Page 111-116
Alborz Geramifard; Peyman Nayeri; Reza Zamani-Nasab & Jafar Habibi, Department of Computer Engineering, Sharif University of Technology, Tehran, Iran

Abstract: This paper presents a new architecture called FAIS for implementing intelligent agents cooperating in a special Multi Agent environment, namely the RoboCup Rescue Simulation System. This is a layered architecture which is customized for solving fire extinguishing problem. Structural decision making algorithms are combined with heuristic ones in this model, so it's a hybrid architecture.
Keywords: FAIS, multi-agent system, RoboCup, rescue simulation, layered architecture

Dynamic Balance Control of Multi-arm Free-Floating Space Robots, Page 117-124
Panfeng Huang, Yangsheng Xu & Bin Liang, Department of Automation and Computer-Aided Engineering, The Chinese University of Hong Kong, Hong Kong, P.R. China

Abstract: This paper investigates the problem of the dynamic balance control of multi-arm free-floating space robot during capturing an active object in close proximity. The position and orientation of space base will be affected during the operation of space manipulator because of the dynamics coupling between the manipulator and space base. This dynamics coupling is unique characteristics of space robot system. Such a disturbance will produce a serious impact between the manipulator hand and the object. To ensure reliable and precise operation, we propose to develop a space robot system consisting of two arms, with one arm (mission arm) for accomplishing the capture mission, and the other one (balance arm) compensating for the disturbance of the base. We present the coordinated control concept for balance of the attitude of the base using the balance arm. The mission arm can move along the given trajectory to approach and capture the target with no considering the disturbance from the coupling of the base. We establish a relationship between the motion of two arm that can realize the zeros reaction to the base. The simulation studies verified the validity and efficiency of the proposed control method.
Keywords: free-floating space robot, dynamics, dynamic control, coordinated cont rol

Robust Motion Control for Mobile Manipulator Using Resolved Acceleration and Proportional-Integral Active Force Control, Page 125-134
Musa Mailah; Endra Pitowarno & Hishamuddin Jamaluddin, Department of Applied Mechanics, Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, Skudai, Malaysia

Abstract: A resolved acceleration control (RAC) and proportional-integral active force control (PIAFC) is proposed as an approach for the robust motion control of a mobile manipulator (MM) comprising a differentially driven wheeled mobile platform with a two-link planar arm mounted on top of the platform. The study emphasizes on the integrated kinematic and dynamic control strategy in which the RAC is used to manipulate the kinematic component while the PIAFC is implemented to compensate the dynamic effects including the bounded known/unknown disturbances and uncertainties. The effectivenss and robustness of the proposed scheme are investigated through a rigorous simulation study and later complemented with experimental results obtained through a number of experiments performed on a fully developed working prototype in a laboratory environment. A number of disturbances in the form of vibratory and impact forces are deliberately introduced into the system to evaluate the system performances. The investigation clearly demonstrates the extreme robustness feature of the proposed control scheme compared to other systems considered in the study.
Keywords: mobilemanipulator, robust motion control, resolved acceleration control, active force control

Production CAGD – Computer Aided Gripper Design for a Flexible Gripping System, Page 135-138
Michael Sdahl & Bernd Kuhlenkoetter, University of Dortmund, Faculty of Mechanical Engeneering, Chair MGH, Germany

Abstract: This paper is a summary of the recently accomplished research work on flexible gripping systems. The goal is to develop a gripper which can be used for a great amount of geometrically variant workpieces. The economic aspect is of particular importance during the whole development. The high flexibility of the gripper is obtained by three parallel used principles. These are human and computer based analysis of the gripping object as well as mechanical adaptation of the gripper to the object with the help of servo motors. The focus is on the gripping of free-form surfaces with suction cup.
Keywords: flexible gripper, CAD, suction gripper, flexibility in manufacturing

A Descriptive Model of Robot Team and the Dynamic Evolution of Robot Team Cooperation, Page 139-143
Shu-qin Li; Lan Shuai; Xian-yi Cheng; Zhen-min Tang & Jing-yu Yang, Department of Computer Science of Nanjing University of Science and Technology, Nanjing, P.R. China

Abstract: At present, the research on robot team cooperation is still in qualitative analysis phase and lacks the description model that can quantitatively describe the dynamical evolution of team cooperative relationships with constantly changeable task demand in Multi-robot field. First this paper whole and static describes organization model HWROM of robot team, then uses Markov course and Bayesian theorem for reference, dynamical describes the team cooperative relationships building. Finally from cooperative entity layer, ability layer and relative layer we research team formation and cooperative mechanism, and discuss how to optimize relative action sets during the evolution. The dynamic evolution model of robot team and cooperative relationships between robot teams proposed and described in this paper can not only generalize the robot team as a whole, but also depict the dynamic evolving process quantitatively. Users can also make the prediction of the cooperative relationship and the action of the robot team encountering new demands based on this model.
Keywords: robot team, cooperation, dynamic evolution