Other Books by V. Daniel Hunt

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2 MECHATRONICS

3 Other Books by V. Daniel Hunt Artificial Intelligence and Expert System Sourcebook. New York: Chapman and Hall, Dictionary of Advanced Manufacturing Technology. New York: Elsevier/North-Holland, Smart Robots. New York: Chapman and Hall, Industrial Robotics Handbook. New York: Industrial Press, Robotics Dictionary. New York: Elsevier/North Holland, RobotJustification. Springfield, Virginia: Technology Research Corporation, 1984.

4 MECHATRONICS: Japan's Newest Threat v. Daniel Hunt CHAPMAN and HALL New York London

5 First published 1988 by Chapman and Hall 29 West 35th Street, New York, NY Published in Great Britain by Chapman and Hall, Ltd. 11 New Fetter Lane, London EC4P 4EE 1988 by Chapman and Hall Softcover reprint ofthe 1st edition 1988 All rights reserved. No part of this book may be reproduced in any way, or by any means, without permission in writing from the publisher. Library of Congress Cataloging-in-Publication Data Hunt, V. Daniel. Mechatronics: Japan's newest threat. (Chapman and Hall advanced industrial technology series) Includes index. 1. Computer integrated manufacturing systems. I. Title. II. Series. TS155.6.H ' ISBN-13: e-isbn-13: DOl: / Author's Note: This book was prepared as an account of work sponsored by Chapman and Hall. Neither Chapman and Hall, nor Technology Research Corporation, nor any of its employees, nor any of their contractors, subcontractors, consultants, or their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness or usefulness of any information, apparatus, product or process disclosed, or represents that its use would not infringe on privately owned rights. The views, opinions and conclusions in this book are those of the author and do not necessarily represent those of the United States Government. Public domain information and those documents abstracted or used in full, edited or otheiwise used are noted in the acknowledgments or on specific pages or illustrations.

6 Table of Contents PART I BACKGROUND 1 1 INTRODUCTION TO MECHATRONICS 3 What is Mechatronics? 3 The Japanese Approach to Mechatronics 8 Benefits of Mechatronics 11 Challenges to Management and the Organization 14 America Challenged! 18 Summary 23 About This Book 24 2 MECHATRONIC SYSTEM ELEMENTS 26 System Concept 26 PART" APPLICA TlONS 53 3 FACTORY AUTOMATION 55 Applications of Computer-Aided Design 57 Robots for FactoI)' Automation 60 Numerically Controlled Machines for FactoI)' Automation 63 Mechatronic Applications 64 4 OFFICE AUTOMATION 67 The Automated Office-Present and Future 67 Basic Functions for an Automated FactoI)' 71 Users and Providers of Information 73

7 VI Table of Contents Telecommunication and Infonnation Processing 76 Office Automation Technologies 80 Data Bases for Office Automation 108 Office Automation and Manufacturing Interface 113 Mechatronics and Office Automation HOME AUTOMATION 119 The Home of the Future 119 Home Infonnation Systems 123 The Automated Kitchen 128 Home Security Systems 131 Heating, Ventilation, and Air Conditioning 134 Water and Energy Management 135 Home Master Control 138 Personal Robots 139 PART 11/ TECHNOLOGY COMPUTER INTEGRATED SYSTEMS Introduction to Computer-Integrated Systems Computer-Aided Design (CAD) Computer-Aided Manufacturing Tools and Strategies for Manufacturing Management Artificial Intelligence in Manufacturing 7 SMART ROBOTS Introduction to Robotics Robot System Elements Robot Sensor Systems End-Effector Tooling for Robots Implementation of Robotics Typical Robot Applications The Future of Robotics 8 MACHINE VISION SYSTEMS Framework for Machine Vision Elements of Machine Vision Practical Machine Vision Systems The State of the Art in Machine Vision

8 Table of Contents VII PART IV ASSESSMENT TECHNOLOGY ASSESSMENT 267 Manipulators and Actuators 268 Precision Mechanisms 274 Machine Vision Systems 282 Non-Vision Sensor Systems 287 Artificial Intelligence 292 Software for Mechatronics 298 Flexible Manufacturing Systems 302 Assembly/Inspection Systems TRENDS IN MECHATRONICS 310 The Future of Mechatronics 310 Growth in Computer Technology 311 World Market Trends 319 Trends in Factory Automation 322 Trends in Office Automation 333 Trends in Home Automation A BLUEPRINT FOR THE FUTURE 351 Opportunity for System Integration 351 Enhanced Productivity 354 Impact on People and Jobs 358 Changes in Education 363 APPENDIX A GLOSSARY 367 APPENDIX 8 REFERENCE MA TERIALS 371 Bibliography 371 Japanese Information Sources 375 U.S. Report on Mechatronics 377 Mechatronics Standards 377 INDEX 379

9 This book is dedicated to Donald W. Keehan, who has contributed, in every way possible, to its successful development.

10 Part I Background

11 Chapter 1 Introduction to Mechatronics What is "Mechatronics"? "Mechatronics" is a term coined by the Japanese to describe the integration of mechanical and electronic engineering. The concept may seem to be anything but new, since we can all look around us and see a myriad of products that utilize both mechanical and electronic disciplines. Mechatronics, however, specifically refers to a multidisciplined, integrated approach to product and manufacturing system design. It represents the next generation of machines, robots, and smart mechanisms necessary for carrying out work in a variety of environments-primarily, factoi)' automation, office automation, and horne automation as shown in Figure 1-1. FACTORY AUIDMATION OFFICE AUIDMATION HOME AUIDMATION Figure 1-1. Mechatronic Environments. 3

12 4 Mechatronics-Japan's Newest Threat By both implication and application, mechatronics represents a new level of integration for advanced manufacturing technology and processes. The intent is to force a multidisciplinary approach to these systems as well as to reemphasize the role of process understanding and control. This mechatronic approach is currently speeding up the already-rapid Japanese process for transforming ideas into products, as shown in Figure 1-2. Currently, mechatronics describes the Japanese practice of using fully integrated teams of product designers, manufacturing, purchasing, and marketing personnel acting in concert with each other to design both the product and the manufacturing system. The Japanese recognized that the future in production innovation would belong to those who learned how to optimize the marriage between electronic and mechanical systems. They realized, in particular, that the need for this optimization would be most intense in application of advanced manufacturing and production systems where artificial intelligence, expert systems, smart robots, and advanced manufacturing SPEED OF NEW PRODUCT DEVELOPMENT MECHATRONICS CAD/CAM STAND-ALONE SYSTEMS Figure 1-2. Mechatronics Transforms Ideas into Products Faster than Traditional Approach.

13 Introduction to Mechatronics 5 technology systems would create the next generation of tools to be used in the factory of the future. From the very beginnings of recorded time, mechanical systems have found their way into every aspect of our society. Our simplest mechanisms, such as gears, pulleys, springs, and wheels, have provided the basis for our tools. Our electronics technology, on the other hand, is completely twentieth-century, all of it created within the past 75 years. Until now, electronics were included to enhance mechanical systems' performance, but the emphasis remained on the mechanical product. There had never been any master plan on how the integration would be done. In the past, it had been done on a case-by-case basis. More recently, however, because of the overwhelming advances in the world of electronics and its capability to physically simplijy mechanical configurations, the technical community began to reassess the marriage between these two disciplines. The most obvious trend in the direction of mechatronic innovation can be observed in the automobile industry. There was a time when a car was primarily a mechanical marvel with a few electronic appendages (Figure 1-3). First came the starter motor, and then the generator, each making Figure 1-3. Model T Ford Production Line. Source: Reprinted with the perrn,ission of Ford Motor Company

14 6 Mechatronics-Japan's Newest Threat the original product a bit better than it was before. Then came solid-state electronics, and suddenly the mechanical mruvel became an electromechanical mruvel. Today's machine is controlled by microprocessors, built by robots, and fault-analyzed by a computer connected to its "external interface connector." Automotive mechanical engineers are no longer the masters of their creations. The process that describes the evolution of the automobile is somewhat typical of other products in our society. Electronics has repeatedly improved the performance of mechanical systems, but that innovation has been more by serendipity than by design. And that is the essence of mechatronics-the preplanned application of, and the efficient integration of, mechanical and electronics technology to create an optimurnnproducl A recent U.S. Department of Commerce report entitled "JTECH Panel Report on Mechatronics in Japan" compared U.S. and Japanese research and development trends in specific areas of mechatronics technology as shown in Figure 1-4. Except for a few areas, the technology necessary to accomplish the development of the next generation of systems embodying the principles of mechatronics is fully within the technological reach of the Japanese. Comparisons were made in three categories: basic research, advanced development, and product implementation. Except for machine vision and software, Japanese basic research was comparable to the United States, with the Japanese closing in fast on machine vision system technology. Japanese artificial intelligence research is falling behind, primarily because the Japanese do not consider it an essential ingredient of their future systems, they appear capable of closing even that gap, if required. In the advanced development and product implementation areas, Japan is equal to or better than the United States, and is continuing to pull ahead at this time. The Department of Commerce report concluded that Japan is maintaining its position and is in some cases gaining ground over the United States in the application of mechatronics. Their progress in mechatronics is important because it addresses the very means for the next generation of data-driven advanced design and manufacturing technology. In fact, the Department of Commerce report concludes that this has created a regenerative effect on Japan's manufacturing industries. To close the gap, we will need to go much further than creating new tools. If we accept the fact that mechanical systems optimally coupled with electronics components will be the wave of the future, then we must also understand that the ripple effect will be felt all the way back to the university, where we now keep the two disciplines of mechanics and electronics separated and allow them to meet only in occasional

15 Introduction to Mechatronics 7 Category Basic Advanced Product Research Development Implementation FMS o Vision Non-vision O Assembly O+- >1 >1 Intelligent mechanisms O+- I Software <, I Standards O Manipulators Precision mechanism Coding System - Present Status Japan Compared to U.S.: Rate of Change < FAR BEHIND t PULLING AWAY - BEHIND I GAINING GROUND 0 EVEN... HOLDING CONSTANT + AHEAD " FALLING BEHIND > FAR AHEAD t LOSING QUICKLY Figure 1-4. Department of Commerce Mechatronics Assessment Summary. Source: JTECH panel report on Mechatronics in Japan, JTECH-TAR-8402 overview sessions. New curricula must be created for a new hybrid engineer-a mechatronics engineer. Only then can we be assured that future generations of product designers and manufacturing engineers will fully seek excellence in these new techniques. We need to rethink our present-day approach of separating our engineering staffs both from each other and from the production engineers. Uving together and communicating individual knowledge will create a

16 8 Mechatronics-Japan's Newest Threat new synergistic effect on products. Maximum interaction will be the key to optimum designs and new product development. The definition of mechatronics is much more significant than its combined words imply. It can physically tum engineering and manufacturing upside down. It will change the way we design and produce the next generation of high technology products. The nation that fully implements the rudiments of mechatronics and vigorously pursues it will lead the world to a new generation of technology innovation with all its profound implications. The Japanese Approach to Mechatronics American indusny is just beginning to realize that the Japanese production advantage cannot be explained by culture or work ethic. It might, however, be explained by their philosophy and practice of mechatronics. This "optimum combination of electronic and mechanical engineering" has led the Japanese to structure the factory environment with precision-design features highlighted by both simple solutions to problems and use of state-of-the-art technology when required. The Japanese are already cornering the marketplace on consumer electronics, office machines, semiconductor fabrication equipment, precision optics, automation devices, computer peripherals, robots, and flexible manufacturing systems. The current Japanese mechatronics effort should rank high as an area of u.s. national concern for several reasons: The pragmatic approach of the Japanese, coupled with their particular infrastructure, allows them to create systems very rapidly with present technology. Using minimal on-line sensors, they create systems by coupling product design to current technology, and use people whenever the technology is missing or fails them. Most large Japanese firms are supported by large production technology centers that can produce the needed systems rapidly and independently of the supplier marketplace. Their approach stresses gaining market share, then profitability. In the United States, users depend on suppliers, and suppliers generate new systems only if they are assured of a profit. The U.S. "Factory-of-the-Future" approach taken by a number of companies offers integration of manufacturing systems but does not address the full user-supplier infrastructure issue. Several large U.S. companies, notably IBM, GM, and GE, are addressing the infrastruc-

17 Introduction to Mechatronics 9 ture issue by acting as their own suppliers, but this does not help the small and mid-sized company, which is the base of U.S. manufacturing capabilities. Until the user-supplier infrastructure question is addressed, the United States may continue to lag behind Japan in implementing new systems. Japan appears to be embarked on a broad spectrum approach to intelligent mechanisms. An information-control versus an artificial intelligence approach to advanced robotics and process problems may be the method used by the Japanese to accelerate their basic research programs for intelligent machines. Currently, they lag significantly behind the United States in intelligent systems and complex autonomous system research, but they have started such work. The question is which strategy will they use, and when will they catch us? Previous history of the Japanese approach in implementing new products quickly, together with the potential of many new production systems available from mechatronic techniques, is expected to provide a strong economic advantage for the Japanese, which will help them further accelerate their growth and use of even more mechatronic technology. There is a significant difference between the Japanese and American approach to the planning and implementation phases of any development program. American visitors to Japanese engineering facilities that use mechatronic techniques find themselves completely frustrated when they try to get a Japanese engineer to move on an idea or to solve a problem. It seems that the Japanese engineer first studies the problem, then conducts research, talks about it with his colleagues, does some more thinking, and then finally decides upon an approach and moves cautiously toward a solution. It could take weeks or months before the Japanese engineer is satisfied that enough information was available and understood. In the United States, the planning phase is abbreviated and the implementation phase is given more emphasis, almost as if there is a belief that planning is not as valuable as implementation. This tendency might stem from our national inclination to want to move out and get the job done. Every engineer in America has, at one time or another, been accused of gold-plating a design; but most engineers are, in fact, never fully satisfied with their design. Getting them to the point of design-freeze can be a perplexing problem to manufacturing engineers and other players on the product team who can't do much without the final design. As a result,

18 10 Mechatronics-Japan's Newest Threat engineers are pushed to freeze the design at the earliest possible time. The working phrase is "never enough time to do it right," but "always enough time to do it over again." The disparity between implementation and planning in American engineering functions and their Japanese mechatronic counterparts has great significance in explaining the differences in quality between American and Japanese products. Perhaps our approach causes us to improve quality incrementally as customers demand it, and to stop when they appear satisfied. The problem with that approach is that there is always a new customer with a new set of ideas on what the acceptable level of quality should be. The mechatronic planning phase in the Japanese development cycle is not a formal time interval, set aside for planning purposes only. If it were, the operation would not appear as slow and drawn out as it does, since the end points of the planning period would be identifiable. The Japanese seem to do whatever is required for each design or problem, using all the time they feel necessary to understand fully what will be needed. Unlike the American practice in which the planners are generally not the implementors, the Japanese design engineers poring over piles of plans and data will more than likely be the implementors as well. Having a stake in the possible solutions and knowing that what is agreed to will also be their next job, participants want to become deeply involved in the process. It is not uncommon to find some very senior level people involved in the implementation phase of Japanese mechatronic activity. Everyone works on the problem or its subsets with little regard for precise skill/work matching. The mechatronic effort is, in essence, a team approach where the necessary talent blends in and out of the scene as required. The Japanese do not place nearly as much emphasis on job categories as we do in America. The president of the company may be found working on a problem on the line with the other workers. At the center of the Japanese approach is an awareness that many kinds of skills are required to make a good product, and anyone of them, if poorly applied, could defeat the work of all the rest. Job/skill class distinctions are, by American standards, blurred. Another distinctive feature of the implementation portion of the mechatronic work in Japan has to do with the nature of the detail tasks. The Japanese look on any part of the problem solving effort as valuable and worthy of involvement. Even the most boring and tedious aspects of a task are not shunned and passed off to someone else. Here, too, the mindset seems to be one of "unity of purpose" and "do it right the first time." Finally, it has been said that the Japanese engineers do not appear

19 Introduction to Mechatronics 11 to be as creative as ours. This feeling might stem from their slow, methodical, apparently drawn-out approach to getting the job done. There was a time in the past when many of their products were reverseengineered copies of our own products, placed in the marketplace in competition with ours. Few knowledgeable people today would say that the Japanese are only copiers of others. On the contrary, we and the rest of the world are studying their processes and designs to find out why we have become second best in areas where we had no competition before. Whether it is a protracted planning phase, more unified worker involvement, or both, the American engineering function could benefit from. a review of the Japanese mechatronics problem-solving process and the results achieved in getting the job done. From beginning to end, the Japanese have used the mechatronics process, which is more fully integrated and teamwork oriented, with a unity of purpose for product market analysis, production, and distribution. The Japanese team decides up front on what they will or will not do to the product to make it a reliable and marketable commodity. Their standard of excellence seems to be their worker, whom they keep fully involved in the product development cycle. Management does not dictate incremental quality; the worker watches for it at every tum. Benefits of Mechatronics Mechatronics may sound like utopia to many product and manufacturing managers because it is often presented as the solution to nearly all of the problems in manufacturing. In particular, it promises to increase productivity in the factory dramatically. Design changes are easy with extensive use of mechatronic elements such as CAD; CAP and MIS systems help in scheduling; and flexible manufacturing systems, computer-aided design, and computer-integrated manufacturing equipment cut turnaround time for manufacturing. These subsystems minimize production costs and greatly increase equipment utilization. Connections from CAE, CAD, and CAM help create designs that are economical to manufacture; control and communications are improved,. with minimal paper flow; and CAM equipment minimizes time loss due to setup and materials handling. Many companies that make extensive use of computers view their factories as examples of mechatronic concepts, but on close examination their integration is horizontal-in the manufacturing area only-or at best includes primarily manufacturing and management. General Electric, as part of its effort to become a major vendor of factory automation systems, has embarked on ambitious plans for integration at several of

20 12 Mechatronics-Japan's Newest Threat its factories, including its Erie Locomotive Plant, its Schenectady Steam Turbine Plant, and its Charlottesville Controls Manufacturing Division. The primary benefits of mechatronics, with an emphasis on advanced manufacturing technology and factory automation, are summarized below. High Capital Equipment Utilization 'TYPically, the throughput for a set of machines in a mechatronics system will be up to three times that for the same machines in a stand-alone job shop environment. The mechatronic system achieves high efficiency by having the computer schedule every part to a machine as soon as it is free, simultaneously moving the part on the automated material handling system and downloading the appropriate computer program to the machine. In addition, the part arrives at a machine already fixtured on a pallet (this is done at a separate work station) so that the machine does not have to wait while the part is set up. Reduced Capital Equipment Costs The high utilization of equipment results in the need for fewer machines in the mechatronic system to do the same work load as in a conventional system. Reductions of 3:1 are common when replacing machining centers in a job-shop situation with a mechatronic system. Reduced Direct Labor Costs Since each machine is completely under computer control, full-time oversight is not required. Direct labor can be reduced to the less skilled personnel who fixture and defixture the parts at the work station, and a machinist to oversee or repair the work stations, plus the system supervisor. While the fixturing personnel in mechatronic environments require less advanced skills than corresponding workers in conventional factories, labor cost reduction is somewhat offset by the need for computing and other skills which may not be required in traditional workplaces. Reduced Work-in-Process Inventory and Lead Time The reduction of work-in-process in a mechatronic system is quite dramatic when compared to a job-shop environment. Reductions of 80