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Computer-Aided Materials Selection During Structural Design
Committee on Application of Expert Systems to Materials Selection During Structural Design
National Materials Advisory Board
Commission on Engineering and Technical Systems
National Research Council
NMAB-467
National Academy Press
Washington, D.C.
1995
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NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competencies and with regard for appropriate balance.
This report has been reviewed by a group other than the authors according to procedures approved by a Report Review Committee consisting of members of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine.
This study by the National Materials Advisory Board was conducted under ARPA Order No. 8475 issued by DARPA/CMO under Contract No. MDA 972-92-C-0028 with the U.S. Department of Defense and the National Aeronautics and Space Administration.
The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the official policies, either expressed or implied, of the Defense Advanced Research Projects Agency or the U.S. Government.
Library of Congress Catalog Card Number 94-69233
International Standard Book Number 0-309-05193-2
Available in limited supply from:
National Materials Advisory Board
2101 Constitution Avenue, NW
Washington, D.C. 20418
202-334-3505 nmab@nas.edu
Additional copies are available for sale from:
National Academy Press
2101 Constitution Avenue, NW Box 285 Washington, D.C. 20055 800-624-6242 202-334-3313 (in the Washington Metropolitan Area)
Copyright 1995 by the National Academy of Sciences. All rights reserved.
Printed in the United States of America.
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Abstract
The selection of the proper materials for a structural component is a critical engineering activity. It is governed by many, often conflicting factors that typically include service requirements, design life, materials availability, database accessibility, manufacturing constraints, repair and replacement strategies, client preferences, and cost. The incorporation of computer-aided materials selection systems into computer-aided design and computer-aided manufacturing operations could assist designers by suggesting potential manufacturing processes for particular products to facilitate concurrent engineering, recommending various materials for a specific part based on a given set of characteristics, or proposing possible modifications of a design if suitable materials for a particular part do not exist. This report reviews the structural design process, determines the elements and capabilities required for a computer-aided materials selection system to assist design engineers, and recommends the research and development areas of materials database, knowledge base, and modeling required to develop a computer-aided materials selection system.
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The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Bruce Alberts is president of the National Academy of Sciences.
The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. Robert M. White is president of the National Academy of Engineering.
The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an advisor to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Kenneth I. Shine is president of the Institute of Medicine.
The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy's purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Bruce Alberts and Dr. Robert M. White are chairman and vice chairman, respectively, of the National Research Council.
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Committee on Application of Expert Systems to Materials Selection During Structural Design
FRANK W. CROSSMAN Chair, Director,
Material Sciences, Lockheed Palo Alto Research Laboratory, Palo Alto, California
JAN D. ACHENBACH, Director,
Center for Quality Engineering and Failure Prevention, Northwestern University, Evanston, Illinois
HAROLD L. GEGEL, Director,
Processing Science Division, Universal Energy Systems, Dayton, Ohio
RICHARD N. HADCOCK, Vice President,
RNH Associates, Inc., Huntington, New York
THOMAS S. KACZMAREK,
North American Operation Manufacturing Center, General Motors Corporation, Warren, Michigan
J. GILBERT KAUFMAN, Vice President,
Technology, The Aluminum Association, Washington, D.C.
MICHAEL ORTIZ,
Engineering Department, Brown University, Providence, Rhode Island
FRIEDRICH B. PRINZ,
Rodney H. Adams Professor of Engineering,
Departments of Mechanical Engineering and Materials Science, Stanford University, Stanford, California
JAN SCHREURS,
Westinghouse Science and Technology Center, Westinghouse Electric Company, Pittsburgh, Pennsylvania
VOLKER WEISS, Professor of Engineering and Physics, Chairman,
Department of Mechanical Aerospace and Manufacturing Engineering, Syracuse University, Syracuse, New York
LIAISON REPRESENTATIVES
RALPH P. I. ADLER, Chief,
Metals Research Branch, Army Research Laboratory—Materials Directorate, Watertown, Massachusetts
WILLIAM BARKER,
Defense Sciences Office, Defense Advanced Research Projects Agency, Arlington, Virginia
ANDREW CROWSON, Director,
Metallurgy and Materials Science Division, Research Triangle Park, North Carolina
WALTER M. GRIFFITH, Deputy Director,
Metals and Ceramics Division, Materials Directorate, Wright Patterson Air Force Base, Ohio
CRAIG MADDEN,
Research Engineering Group, David Taylor Research Center, Bethesda, Maryland
RONALD G. MUNRO, Physicist,
Ceramics Division, National Institute of Standards and Technology, Gaithersburg, Maryland
NMAB STAFF
ROBERT M. EHRENREICH, Senior Staff Officer
PAT WILLIAMS, Senior Secretary
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Acknowledgments
The committee would like to express its appreciation to the following individuals for their presentations to the committee: J. Hendrix of Hercules Incorporated, O. Richmond of ALCOA, and D. Marinaro of PDA Engineering. The committee would also like to thank Larry Ilcewicz for hosting a site visit to the Boeing facility in Seattle, Washington, and the following individuals for their presentations: H. Shomber, A. Falco, T. Lackey, T. Richardson, B. Das, B. Backman, A. Miller, J. Boose, P. Rimbos, and G. Swanson. The committee acknowledges with thanks the contributions of Robert M. Ehrenreich, Senior Staff Officer, and Pat Williams, Senior Secretary, to the project.
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Preface
The Department of Defense and the National Aeronautics and Space Administration requested that the National Materials Advisory Board convene a committee to study the application of expert systems to materials selection during structural design. The objectives of the study were to determine (1) the components needed for an effective computer-assisted, concurrent engineering design system, (2) the barriers preventing the development of such a system, and (3) the research and development required to construct such a system.
The committee met six times between June 1991 and September 1992. The first meeting focused on developing a perspective on the study scope and an approach for assessing the primary, underlying technologies pertinent to the study via case studies and an industry site visit.1 The second meeting provided an opportunity for each committee and liaison member to describe his or her research and technical experience pertinent to the committee charter. Committee members also presented case studies of computer-aided materials selection systems with which they had experience. This helped determine the state of the art of such systems and provide examples of design decisions involving geometric relations; design rules associated with performance, processing, manufacturing, and supportability; and advanced computer concepts and technologies that aid the design optimization process. The committee then held three study sessions focused on product design, materials supply and development, and state-of-the-art computer-aided systems technology for materials selection. The first study session consisted of a site visit to the Boeing Commercial Airplane Company in Seattle, Washington, to learn about materials selection within the airplane design process. The second session consisted of presentations by representatives of ALCOA and Hercules on materials modeling, certification, and the supplier-designer interaction. The third session focused on computer demonstrations of some state-of-the-art systems that aid the materials selection process, to determine current capabilities and identify barriers to the development of an optimal system.
This report is divided into five chapters. Chapter 1 defines the study scope and committee charge. Chapter 2 places materials selection within the context of the design process, using the Boeing Commercial Airplane Group as a case study. Chapter 3 presents the committee's vision of a full-function, computer-aided materials selection system. Chapter 4 reviews the underlying information technologies pertinent to the materials selection process, determined by the examination of the case studies listed in Appendix B. Chapter 5 discusses the issues preventing the development of computer-aided materials selection systems and outlines the recommendations for the research and development required to attain the envisioned system. The appendices include (1) a glossary of acronyms, (2)
1
The number of computer-aided systems on the market is rapidly growing, with new products being introduced daily (see Schorr and Rappaport, 1989; Rappaport and Smith, 1991; Smith and Scott, 1991). Since any compilation of systems would be rapidly out-of-date, the committee determined the current capabilities of computer-aided systems by examining the 30 case studies listed in Appendix B.
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a complete list of the case studies reviewed by the committee, (3) a review of some of the knowledge-representation tools and technologies discussed in the report, and (4) two examples of the case studies reviewed by the committee that typify the materials selection and database systems currently available.
Comments or suggestions that readers of this report wish to make can be sent via Internet electronic mail to nmab@nas.edu or by FAX to the National Materials Advisory Board at 202/334-3718.
Frank W. Crossman, Chair
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Contents
EXECUTIVE SUMMARY
1
Vision of a Computer-Aided Materials Selection System
1
Strategies for Overcoming Barriers
2
General Conclusions and Recommendations
4
1
INTRODUCTION
7
Benefits
7
Definitions
8
Study Objectives and Scope
8
2
MATERIALS SELECTION IN STRUCTURAL DESIGN
11
Concurrent Engineering and Design Organization
11
Materials Selection During Computer-Aided Design
13
Summary of Materials Information Requirements in Design
15
3
ENHANCING THE MATERIALS SELECTION PROCESS IN DESIGN: A VISION
19
Integrated Engineering Support in Integrated Enterprises
19
Supporting Strategic Material Decisions
20
Supporting Routine Material Decisions
21
Supporting Innovative Materials Selection in Design
21
Summary
22
4
INFORMATION TECHNOLOGIES PERTINENT TO THE MATERIALS SELECTION PROCESS
25
Databases and Knowledge Bases
25
Modeling and Analysis Systems
29
5
CONCLUSIONS AND RECOMMENDATIONS
37
Strategies for Overcoming Barriers
37
General Conclusions and Recommendations
39
References
41
Appendix A:
Glossary of Acronyms
45
Appendix B:
Case Studies Reviewed by the Committee
47
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Appendix C:
Review of Selected Knowledge-Representation Techniques and Tools
49
Appendix D:
Knowledge-Based Integrated Design System
57
Appendix E:
An Intelligent Knowledge System for Selection of Materials for Critical Aerospace Applications
63
Appendix F:
Biographical Sketches of Committee Members
69
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List of Figures
2-1
The sequential engineering approach to structural design
11
2-2
A typical comparison of sequential and concurrent engineering
12
2-3
An example of a typical structures DBT hierarchy: Boeing 777 horizontal stabilizer DBTs
12
2-4
The expertise in a structural design concurrent engineering team
13
2-5
The interactions of a typical DBT
13
2-6
A model of the wing of the Grumman X-29 and associated finite element analysis
14
2-7
Structures and materials design interactions
15
3-1
The conceptual architecture of a Computer-Aided Materials Selection System
24
4-1
Automobile side marker
30
4-2
Concurrent engineering environment including inspectability
33
4-3
POD curves for two scanning plans
35
C-1
The differences between wireframe, surface model, and solid model representational domains
52
C-2
An example of the LOOS system to define the structure or ''topology" of a layout
55
D-1
Information flow in IPD
58
D-2
Methods developers' frame of reference
59
D-3
Control flow between roles in the blade design assistant
60
D-4
Blade design assistant
61
E-1
Model of an intelligent knowledge system applicable to the material selection problem
64
E-2
Specific system architecture for the prototype IKSMAT
64
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List of Tables
2-1
Examples of Materials Information Required During Product Design
16
2-2
Typical Product Design Requirements for Aircraft Structure Development
16
2-3
Summary of Designer "Wants"
17
3-1
Summary of the Materials-Specific Information Technologies and Some of the Primary Computer Technologies Required for a Computer-Aided Materials Selection System
23
4-1
Representative Applications Based on Knowledge of Materials
27
4-2
Steps in the Development of a Process Model
31
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Computer-Aided Materials Selection During Structural Design
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