Computational Principles of Mobile Robotics

Transcription

1 Computational Principles of Mobile Robotics Mobile robotics is a multidisciplinary field involving both computer science and engineering. Addressing the design of automated systems, it lies at the intersection of artificial intelligence, computational vision, and robotics. This textbook for advanced undergraduates and graduate students emphasizes computation and algorithms for a range of strategies for locomotion, sensing, and reasoning. It concentrates on wheeled and legged mobile robots but also discusses a variety of other propulsion systems. The new edition presents advances in robotics and intelligent machines over the last 10 years, including significant coverage of SLAM (simultaneous localization and mapping) and multi-robot systems. It includes additional mathematical background and an extensive list of sample problems. Various mathematical techniques that were assumed in the first edition are now briefly introduced in appendices at the end of the text to make the book more self-contained. Researchers and students in the field of mobile robotics will appreciate this comprehensive treatment of state-of-the-art methods and key technologies. Gregory Dudek is James McGill Professor of Computer Science and the Director of the School of Computer Science and of the Mobile Robotics Laboratory at McGill University. Michael Jenkin is a Professor of Computer Science and Engineering at York University. He has coedited eight books on human and machine vision.

2 Computational Principles of Mobile Robotics Second Edition Gregory Dudek McGill University Michael Jenkin York University

3 CAMBRIDGE UNIVERSITY PRESS Cambridge, New York, Melbourne, Madrid, Cape Town, Singapore, São Paulo, Delhi, Dubai, Tokyo, Mexico City Cambridge University Press 32 Avenue of the Americas, New York, NY , USA Information on this title: / Cambridge University Press 2010 This publication is in copyright. Subject to statutory exception and to the provisions of relevant collective licensing agreements, no reproduction of any part may take place without the written permission of Cambridge University Press. First published 2010 Printed in the United States of America A catalog record for this publication is available from the British Library. Library of Congress Cataloging in Publication data Dudek, Gregory, 1958 Computational principles of mobile robotics / Gregory Dudek, Michael Jenkin. 2nd ed. p. cm. Includes bibliographical references and index. ISBN Mobile robots. 2. Robotics Mathematics. I. Jenkin, Michael, 1959 II. Title. TJ D dc ISBN ISBN Hardback Paperback Cambridge University Press has no responsibility for the persistence or accuracy of URLs for external or third-party Internet Web sites referred to in this publication and does not guarantee that any content on such Web sites is, or will remain, accurate or appropriate.

4 For Krys and Heather

5 Contents Acknowledgments Preface to the Second Edition page xi xiii 1 Overview and Motivation From Mechanisms to Computation Historical Context Biological Inspiration Operational Regimes Operational Modes A Guide to This Book Further Reading Problems 16 2 Fundamental Problems Path Planning for a Point Robot Localization for a Point Robot Sensing for a Point Robot Mapping for a Point Robot SLAM for a Point Robot Looking Forward Further Reading Problems 27 Part One: Locomotion and Perception 29 3 Mobile Robot Hardware Locomotion Off-Board Communication Processing Further Reading Problems 77 4 Non-Visual Sensors and Algorithms Basic Concepts Contact Sensors: Bumpers 86 vii

6 viii Contents 4.3 Inertial Sensors Infrared Sensors Sonar Radar Laser Rangefinders Satellite-Based Positioning Data Fusion Biological Sensing Further Reading Problems Visual Sensors and Algorithms Visual Sensors Object Appearance and Shading Signals and Sampling Image Features and Their Combination Obtaining Depth Active Vision Other Sensors Biological Vision Further Reading Problems 164 Part Two: Representation and Planning Representing and Reasoning About Space Representing Space Representing the Robot Path Planning for Mobile Robots Planning for Multiple Robots Biological Mapping Further Reading Problems System Control Horizontal Decomposition Vertical Decomposition Hybrid Control Architectures Middleware High-Level Control Alternative Control Formalisms The Human Robot Interface Mobile Robot Software Development as Experimentation Standard Software Toolkits 237

7 Contents ix 7.10 Further Reading Problems Pose Maintenance and Localization Simple Landmark Measurement Servo Control Recursive Filtering Non-Geometric Methods: Perceptual Structure Correlation-Based Localization Global Localization Biological Approaches to Localization Further Reading Problems Mapping and Related Tasks Sensorial Maps Geometric Maps Topological Maps Exploration Further Reading Problems Robot Collectives Categorizing Collectives Control Architectures Collective Communication Sensing Planning for Action Formation Control Localization Mapping Further Reading Problems Robots in Practice Delivery Robots Intelligent Vehicles Robots for Survey and Inspection Mining Automation Space Robotics Autonomous Aircraft Military Reconnaissance Bomb/Mine Disposal Underwater Inspection Agriculture/Forestry Aids for the Disabled 325

8 x Contents Entertainment Domestic Robots Further Reading Problems The Future of Mobile Robotics Locomotion Sensors Control System Integration Standardization Future Directions 333 Appendix A: Probability and Statistics 335 A.1 Probabililty 335 A.2 Some Simple Statistics 338 A.3 Further Reading 339 A.4 Problems 339 Appendix B: Linear Systems, Matrices, and Filtering 341 B.1 Linear Algebra 341 B.2 Matrix Algebra 341 B.3 Signals and Systems 343 B.4 Fourier Theory 344 B.5 Sampling and the Nyquist Theorem 344 B.6 Further Reading 345 B.7 Problems 345 Appendix C: Markov Models 346 C.1 Discrete Markov Process 346 C.2 Hidden Markov Models 348 C.3 Markov Decision Process 349 C.4 POMDP 350 C.5 Further Reading 351 C.6 Problems 351 Bibliography 353 Index 381

9 Acknowledgments This book would not have been possible without the active support of our students and colleagues who suffered through early drafts, provided imagery and papers, and put up with us while this volume was being put together. The list of people who helped is much too long to include here, but some require special mention: International Joint Conferences on Artificial Intelligence (IJCAI), for letting us do a tutorial on mobile robotics that started us on the journey; students at McGill and York, including Eric Bourque, Andrew Hogue, and Yiannis Rekleitis, who suffered with photocopies of early drafts; Prof. Evangelos Milios for his helpful comments and Prof. Evangelos Papadopoulos for his help on space robots; Rob Sim for his figures; and Louis Dudek for his proofreading and helpful comments. Finally, we thank Lauren Cowles and Cambridge University Press for encouraging us do this in the first place. xi

10 Preface to the Second Edition The authors surrounded by a collection of some of their robots and sensors. The first edition of this book arose from a tutorial that was initially presented in It evolved over a number of years and finally appeared in Robotics is, of course, a rapidly changing field, and even as the first edition was appearing, it was apparent that it would become dated rather quickly. Thus in late 2002, the first steps were taken toward a second edition. The field of mobile robotics continues to evolve, and this book has (we hope) evolved with the field. Topics that were in their infancy when the first edition was published such as SLAM and multi-robot systems have evolved into much more mature disciplines. The mathematical foundations of much of mobile robotics has also matured, and this too is reflected in this volume. In addition to updating the various algorithms and methods described in the first edition, the second edition is somewhat more self-contained. Specifically, various mathematical techniques that were assumed in the first edition are now introduced, albeit briefly, in appendices at the end of the text. xiii