Optimal Supervisory Control Of Automated Manufacturing Systems

This monograph presents the state-of-the-art developments in the design of behaviorally and structurally optimal livenessen-forcing Petri net supervisors with computationally tractable approaches. It details optimal supervisory control problems arising in automated production systems and outlines a methodology to achieve the optimality purposes of deadlock prevention via converting a variety of problems under consideration into integer linear programming models. The book includes a reference bibliography at the end of each chapter and a complete index.

Presents strategies with reachability graph analysis for optimizing resource allocation systems Supervisory Control and Scheduling of Resource Allocation Systems offers an important guide to Petri net (PN) models and methods for supervisory control and system scheduling of resource allocation systems (RASs). Resource allocation systems are common in automated manufacturing systems, project management systems, cloud data centers, and software engineering systems. The authors—two experts on the topic—present a definition, techniques, models, and state-of-the art applications of supervisory control and scheduling problems. The book introduces the basic concepts and research background on resource allocation systems and Petri nets. The authors then focus on the deadlock-free supervisor synthesis for RASs using Petri nets. The book also investigates the heuristic scheduling of RASs based on timed Petri nets. Conclusions and open problems are provided in the last section of the book. This important book: Includes multiple methods for supervisory control and scheduling with reachability graphs, and provides illustrative examples Reveals how to accelerate the supervisory controller design and system scheduling of RASs based on PN reachability graphs, with optimal or near-optimal results Highlights both solution quality and computational speed in RAS deadlock handling and system scheduling Written for researchers, engineers, scientists, and professionals in system planning and control, engineering, operation, and management, Supervisory Control and Scheduling of Resource Allocation Systems provides an essential guide to the supervisory control and scheduling of resource allocation systems (RASs) using Petri net reachability graphs, which allow for multiple resource acquisitions and flexible routings.

Control and Dynamic Systems: Advances in Theory and Applications, Volume 46: Manufacturing and Automation Systems: Techniques and Technologies, Part 2 of 5 covers the significant advances and issues on the utilization of techniques and technologies in the manufacturing industries. This volume is divided into nine chapters and starts with the essential issue of software in manufacturing systems, particularly the aspects of the control software that are active in the time-critical or real time portions of the machine's operation. The succeeding chapters deal with the interactions between material-handling systems and other components of manufacturing systems; the principles of flexible manufacturing systems; the various views on the contributions of mechatronics; and the techniques for machine layout optimization in manufacturing and automation systems. These topics are followed by discussions of the application of a real-time control system to address issues of safety, productivity advances, and production cost reductions. Other chapters consider the influence of human supervisory control of predominantly automated manufacturing processes and the techniques for the manufacturing systems integration. The final chapter examines the major importance of the assembly line balancing to manufacturing systems. This book is of great value to process and mechanical engineers, as well as process control workers and researchers.

This book shows how supervisory control theory (SCT) supports the formulation of various control problems of standard types, like the synthesis of controlled dynamic invariants by state feedback, and the resolution of such problems in terms of naturally definable control-theoretic concepts and properties, like reachability, controllability and observability. It exploits a simple, abstract model of controlled discrete-event systems (DES) that has proved to be tractable, appealing to control specialists, and expressive of a range of control-theoretic ideas. It allows readers to choose between automaton-based and dually language-based forms of SCT, depending on whether their preference is for an internal-structural or external-behavioral description of the problem. The monograph begins with two chapters on algebraic and linguistic preliminaries and the fundamental concepts and results of SCT are introduced. To handle complexity caused by system scale, architectural approaches—the horizontal modularity of decentralized and distributed supervision and the vertical modularity of hierarchical supervision—are introduced. Supervisory control under partial observation and state-based supervisory control are also addressed; in the latter, a vector DES model that exploits internal regularity of algebraic structure is proposed. Finally SCT is generalized to deal with timed DES by incorporating temporal features in addition to logical ones. Researchers and graduate students working with the control of discrete-event systems or who are interested in the development of supervisory control methods will find this book an invaluable aid in their studies. The text will also be of assistance to researchers in manufacturing, logistics, communications and transportation, areas which provide plentiful examples of the class of systems being discussed.

Master production scheduling II 60 On-line scheduling 65 Specific data requirements 69 Mailbox approaches 70 Conclusion 72 Chapter 7: Cell Level Control 75 Introduction 75 CCS classification 77 What is a cell? 78 CCS operational modes 80 Conclusion 86 Chapter 8: Equipment Level Control 89 Introduction 89 What is meant by equipment? 90 Equipment level control structure 92 Conclusion 94 Chapter 9: Conclusion and Future Trends 95 Overall production planning and control functions 98 Future trends 100 Conclusion 102 Appendix I: Master Production Scheduling II 103 References 107 Index 109 Preface This book is intended as an introduction to production planning and control of automated manufacturing systems. As such, it links together two diverse fields of interest: in the area of production planning and control there is a large body of work completed in analytical models, computer structures and overall systems; equally, for the hardware and detailed control aspects of the equipment used (for example, NC machines, robots, etc), comprehensive studies have also been completed. To cover each area fully would result in a work of several volumes. Instead, this book stresses the important elements of both areas that are vital to effective production planning and control of the whole automated manufacturing system.

Deadlock problems in flexible manufacturing systems (FMS) have received more and more attention in the last two decades. Petri nets are one of the more promising mathematical tools for tackling deadlocks in various resource allocation systems. In a system modeled with Petri nets, siphons are tied to the occurrence of deadlock states as a structural object. The book systematically introduces the novel theory of siphons, traps, and elementary siphons of Petri nets as well as the deadlock control strategies for FMS developed from it. Deadlock prevention methods are examined comparatively. The many FMS examples presented to demonstrate the concepts and results of this book range from the simple to the complex. Importantly, to inspire and motive the reader’s interest in further research, a number of interesting and open problems in this area are proposed at the end of each chapter.