Effects of Initial Stance of Quadruped Trotting on Walking Stability, Page 003-006
Dongqing He & Peisun Ma, Research Institute of Robotics, Shanghai Jiaotong University, China, School of Mechatronical Engineering, University of Petroleum, China
Abstract: It is very important for quadruped walking machine to keep its stability in high speed walking. It has been indicated that moment around the supporting diagonal line of quadruped in trotting gait largely influences walking stability. In this paper, moment around the supporting diagonal line of quadruped in trotting gait is modeled and its effects on body attitude are analyzed. The degree of influence varies with different initial stances of quadruped and we get the optimal initial stance of quadruped in trotting gait with maximal walking stability. Simulation results are presented.
Keywords: quadruped, trotting, attitude, walking stability
An Agent-based Manufacturing Management System for Production and Logistics within Cross-Company Regional and National Production Networks, Page 007-014
Heinrich, S.; Durr, H.; Hanel, T. & Lassig, J., Department of Manufacturing Systems Engineering, Chemnitz University of Technology, Germany
Abstract: The goal is the development of a simultaneous, dynamic, technological as well as logistical real-time planning and an organizational control of the production by the production units themselves, working in the production network under the use of Multi-Agent-Technology. The design of the multi-agent-based manufacturing management system, the models of the single agents, algorithms for the agent-based, decentralized dispatching of orders, strategies and data management concepts as well as their integration into the SCM, basing on the solution described, will be explained in the following.
Keywords: production engineering and management, dynamic manufacturing planning and control, multi agentsystems (MAS), supply-chain-management (SCM), e-manufacturing
Nonlinear Receding-Horizon Control of Rigid Link Robot Manipulators, Page 015-024
Hedjar, R. & Boucher, P., Supelec, Plateau de Moulon F91192 Gif Sur Yvette Cedex, France
Abstract: The approximate nonlinear receding-horizon control law is used to treat the trajectory tracking control problem of rigid link robot manipulators. The derived nonlinear predictive law uses a quadratic performance index of the predicted tracking error and the predicted control effort. A key feature of this control law is that, for their implementation, there is no need to perform an online optimization, and asymptotic tracking of smooth reference
trajectories is guaranteed. It is shown that this controller achieves the positions tracking objectives via link position measurements. The stability convergence of the output tracking error to the origin is proved. To enhance the robustness of the closed loop system with respect to payload uncertainties and viscous friction, an integral action is introduced in the loop. A nonlinear observer is used to estimate velocity. Simulation results for a two-link rigid robot are performed to validate the performance of the proposed controller.
Keywords: receding-horizon control, nonlinear observer, robot manipulators, integral action, robustness
Audit, Control and Monitoring Design Patterns (ACMDP) for Autonomous Robust Systems (ARS), Page 025-038
Trad, A. & Trad, C., TradSoft, 1007 Lausanne, Switzerland
Abstract: This paper proposes the Audit, Control and Monitoring Design Patterns (ACMDP) for building Autonomous and Robust Systems (ARS) such as Mobile Robot Systems (MRS). These patterns are also applicable to other Mission Critical and Complex Systems (MCCS). This paper presents a proposal which will help ARS project managers and engineers design, build and estimate the probability that an ARS will succeed or fail. Furthermore, this proposal offers the possibility to ARS problems with the help of audit, monitoring and controlling components, adjust the project management pathways, and define the problem sources as well as their possible solutions, in order to deliver an ARS or an MRS.
Keywords: ARS, MRS, design patterns, packages, components, maintenance, audit, control and monitor
Control a 2-Axis Servomechanism by Gesture Recognition using a Generic WebCam, Page 039-044
Tavares, J. M. R. S.; Ferreira, R. & Freitas, F., Departamento de Engenharia Mecanica e Gestao Industrial, Faculdade de Engenharia da Universidade do Porto, Portugal
Abstract: This paper presents two approaches used to control a 2-axis servomechanism by gesture recognition. For both approaches, the adopted control philosophy was: In the system’s learning phase, the control images are acquired by a generic webcam and associated to the desired orders. On the other hand, in the working phase, each control image is acquired, by the same webcam and, by comparison with the stored orders images, the desired order is recognized and processed by the servomechanism in quasi real time. In this paper, the used servomechanism and both implemented approaches are described, and are indicated some advantages and weakness of each one. Two examples of images control sets are also presented, and some conclusions and future works are addressed.
Keywords: computational vision, gesture recognition, object moments, orientation histograms, servomechanism control
Modular Adaptive System Based on a Multi-Stage Neural Structure for Recognition of 2D Objects of Discontinuous Production, Page 045-051
Topalova, I., Department of Automation of Discontinuous Production, Technical University Sofia, Bulgaria
Abstract: This is a presentation of a new system for invariant recognition of 2D objects with overlapping classes, that can not be effectively recognized with the traditional methods. The translation, scale and partial rotation invariant contour object description is transformed in a DCT spectrum space. The obtained frequency spectrums are decomposed into frequency bands in order to feed different BPG neural nets (NNs). The NNs are structured in three stages - filtering and full rotation invariance; partial recognition; general classification. The designed multi-stage BPG Neural Structure shows very good accuracy and flexibility when tested with 2D objects used in the discontinuous production. The reached speed and the opportunuty for an easy restructuring and reprogramming of the system makes it suitable for application in different applied systems for real time work.
Keywords: feature extraction, invariant descriptor, backpropagation, neural network, pattern recognition
Realization of a Service Robot for Cleaning Spherical Surfaces, Page 053-058
Houxiang Zhang; Jianwei Zhang; Rong Liu; Guanghua Zong, Dept. TAMS, Faculty of Computer Science, University of Hamburg, Hamburg, Germany, Robotics Institute, BeiHang University, Beijing, China
Abstract: There are more and more buildings with complicated shape emerging all over the world. Their walls require constant cleaning which is difficult to realize. In this paper, based on analyzing the characteristics of the working target,a new kind of auto-climbing robot is proposed, which is used for cleaning the spherical surface of the National GrandTheatre in China. The robots’ mechanism and unique aspects are presented in detail. A distributed controller based onCAN bus is designed to meet the requirements of controlling the robot. The control system is divided into 6 parts, fiveCAN bus control nodes and a remote controller, which are designed and established based mainly on the P80C592. Finally, the motion function is described in detail. The experimental results confirm the principle described above andthe robot’s ability to work on the spherical surface.
Keywords: spherical surface; auto-climbing robot; mechanism structure; control system; motion function
An Adaptive Control Scheme for Nonholonomic Mobile Robot with Parametric Uncertainty, Page 059-063
Mnif, F. & Touati, F., Sultan Qaboos University, Department of Electrical and Computer Engineering, Oman, Institut National des Sciences Appliquées et de Technologie, Intelligent Control, Design and Optimization of Complex Systems Research Unit, Tunisia
Abstract: This paper addresses the problem of stabilizing the dynamic model of a nonholonomic mobile robot. A discontinuous adaptive state feedback controller is derived to achieve global stability and convergence of the trajectories of the of the closed loop system in the presence of parameter modeling uncertainty. This task is achieved by a non smooth transformation in the original system followed by the derivation of a smooth time invariant control in the new coordinates. The stability and convergence analysis is built on Lyapunov stability theory.
Keywords: nonholonomic system, adaptive control, car-like vehicle
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