Reconfigurable Distributed Control

Abstract

The use of registered names, trademarks, etc., in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant laws and regulations and therefore free for general use.The publisher makes no representation, express or implied, with regard to the accuracy of the information contained in this book and cannot accept any legal responsibility or liability for any errors or omissions that may be made.Typesetting: Electronic camera-ready by authors Printed in the United States of America (SBA) 69/3830-543210 Printed on acid-free paper Preface vi performance degradation during still manageable fault situations. An exhaustive review of model-based and model-free strategies for fault detection is provided to introduce the reader to the area of process monitoring, which looks for a practical approximation of it. Furthermore, an extensive review of network control is given to define how time delays are accommodated due to fault tolerance strategies. To that respect, a guide for how to approximate to this interesting open field is presented.Special mention should be made of the software used in this work; in this case, three major packages are used: first, MATLAB 6.5, especially the Simulink and State Flow toolboxes. The second package is True Time, which is used to simulate the communication network, and it is available through the Internet http://www.control.lth.se/~dan/truetime/; this package has been found to be an efficient tool for understanding the functionality of a network. Finally, ADMIRE is another useful package (ADMIRE, 2003) that is an aerodynamic model of an aircraft, which has presented interesting scenarios under fault and time delay scenarios worthy to be studied in future work.This book is divided into five chapters. The first chapter is a basic review of communication networks in which a description of network protocols is provided based on a common standard of open systems interconnection (OSI); particular interest is presented over the control area network databus (CAN bus) because of its common use over real-time distributed systems. The second chapter is focused on the real-time background, and it presents how a real-time system can define time delays based on its inherent deterministic behavior using scheduling algorithms; in fact, an overview of most classic scheduling algorithms is presented.The outline of the third chapter is based on fault diagnosis strategies for a common and unknown situation, which is an unhealthy scenario. Specifically, this chapter concentrates on a smart element paradigm that understands this element as an autonomous device that can self-diagnose. Chapter 3 presents the most common strategies of fault diagnosis and their use for health treatment.The fourth chapter presents an implementation of the control reconfiguration strategy based on a review of network control systems to pursue a feasible option for safety during fault conditions. Strategies such as time delay modeling, interloop connection, and others such ...