Manufacturing is a complex activity drawing upon many disciplines and technologies, reflecting management attitudes and philosophies, dependent upon organizational structures, influenced by the customers for products and by the suppliers of the many materials, machines, and equipment used to produce those products. Most efforts to develop a science of manufacturing have concentrated on understanding and improving the performance of unit operations and activities, in the belief that maximizing the effectiveness of the separate parts would result in an optimized system. Although our endeavors have provided a greater understanding of the fundamental phenomena underlying the individual components and an increased awareness of the details needed to direct and control them, we are beginning to realize that the complexity of the myriad relationships, interactions, and dependencies of the components and processes precludes such an approach to system optimization. It is now clear that ignoring the many interactions prevents good predictions of system performance and improved controls.

The study on which this report is based was an effort by the National Academy of Engineering to define principles underlying the complexity of manufacturing systems. Many of the findings of this study were presented at an NAE symposium entitled “Foundations of World-Class Manufacturing Systems” held in Washington, D.C., on June 19, 1991. I would like to thank W. Dale Compton, who chaired the symposium and the Committee on

Foundations of Manufacturing, and Joseph A. Heim, the principal staff officer for the project, for their efforts in organizing the symposium and in the publication of this volume. Also, on behalf of the National Academy of Engineering, I would like to thank the committee members (listed on page 254) and the authors who participated in the study and symposium. Special thanks are due to the following individuals in the NAE Program Office who worked on the publication and symposium: H. Dale Langford, Maribeth Keitz, Melvin J. Gipson, Vivienne T. Chin, and Mary J. Ball.

This project was carried out under the auspices of the NAE Program Office, directed by Bruce R. Guile. Partial funding for this effort was provided by the Intel Foundation and the National Academy of Engineering Technology Agenda Program.

ROBERT M. WHITE

President

National Academy of Engineering

Recognition of the complexity of the manufacturing system and the need to view it in its entirety was a principal outcome of the February 1987 National Academy of Engineering conference on “Design and Analysis of Integrated Manufacturing Systems: Status, Issues, and Opportunities. ” The conference identified a need for a more intensive search for the elements of a manufacturing systems discipline, based on the belief that a more effective characterization of manufacturing systems would benefit both practitioners and educators.

In response, the National Academy of Engineering assembled the Committee on Foundations of Manufacturing in early 1989 to address the disciplinary nature of manufacturing systems. The concept of manufacturing as a discipline implies the existence of “basic laws,” a taxonomy, basic theories of design, and optimization procedures. This study has focused on the systems aspects of manufacturing and has been primarily concerned with those generic issues reflected in world-class manufacturing companies and is not intended to address operational solutions to today's manufacturing problems.

The Foundations of Manufacturing Committee met on numerous occasions during 1989 and 1990 to explore the various aspects of manufacturing systems, often meeting with manufacturing experts who are not members of the committee. Individual committee members, as well as the committee, also developed a variety of characterizations of manufacturing systems and

subsystems and began work on developing or obtaining data to illustrate some of the hypothesized relationships. In July 1990 the committee hosted a workshop at the NAS/NAE study center in Woods Hole, Massachusetts, for several manufacturing executives, practitioners, and university educators. The exchange of ideas during the workshop lent further credence to the need to identify the core set of principles or bases on which manufacturing systems could be analyzed, designed, and managed. The enthusiastic reception for the concept and support for the effort to define and generalize these principles led to the development of several papers (included in this volume) that focus on many of the ideas presented during the workshop. The committee draws heavily on these papers in its arguments concerning the importance of these principles and their application in the manufacturing environment.

The committee designated these principles “foundations” of manufacturing because of their comprehensive applicability; they are generic, not specific to a particular industry or company; they are operational in that they lead to specific actions and show directions that should be taken; and their application should lead to improved system performance. These operating principles must be recognized, understood, and aggressively adopted by manufacturing organizations that aspire to world-class performance standards.

This report provides a framework that can be used by manufacturing executives and practitioners to improve their capability to predict the outcomes of product, process, and operating decisions and to assist them in analyzing, designing, and controlling their systems. For educators and those engaged in research, the report identifies opportunities for greater exploration and the discovery of additional foundations of manufacturing systems. Furthermore, it reminds us that intense interdisciplinary interactions of the many contemporary engineering, business, and social disciplines needed by modern manufacturing systems will contribute significantly to the global competitiveness of manufacturing in the United States.

W. DALE COMPTON, Chairman

Foundations of Manufacturing Committee

National Academy of Engineering

MANUFACTURING SYSTEMS