TABLE OF CONTENTS 1. INTRODUCTION ....................................................................................................................... 6 1.1 BACKGROUND .......................................................................................................................... 6 1.2 ENGINEERING DESIGN - A FORM OF INFORMATION PROCESSING................................................. 6 1.3 RESEARCH IN ENGINEERING DESIGN.......................................................................................... 7 1.4 SCOPE AND MOTIVATION OF THIS THESIS .................................................................................. 8 1.5 STRUCTURE OF THIS THESIS ...................................................................................................... 9 2. SCIENTIFIC FRAMEWORK FOR RESEARCH IN DESIGN THEORY............................ 11 2.1 DEFINITION OF SCIENTIFIC THEORY AND DISCUSSION ON HOW THEORIES CAN BE USED............ 11 2.2 RESEARCH PROCESS MODEL FOR DESIGN THEORY................................................................... 12 3. CONTEXT OF THIS THESIS ................................................................................................. 14 3.1 INDUSTRIAL CONTEXT: THE DESIGN PROCESS ......................................................................... 14 3.1.1 Introduction to the design process roadmap..................................................................... 15 3.1.2 Putting together a project specific design process from the activities in the roadmap....... 16 3.1.3 Description of the generic activities in the design activity collection ................................ 17 3.1.3.1 Project control and decomposition ........................................................................................................... 17 3.1.3.2 Design object analysis............................................................................................................................. 17 3.1.3.3 Problem formulation ............................................................................................................................... 18 3.1.3.4 Decoupling (conflict resolution) .............................................................................................................. 19 3.1.3.5 Concept Generation and Selection........................................................................................................... 20 3.1.3.6 Trade-off................................................................................................................................................. 20 3.1.3.7 Implementation ....................................................................................................................................... 21 3.2 ACADEMIC CONTEXT: CONTEMPORARY DESIGN THEORY RESEARCH ....................................... 22 3.2.1 Motivation and Scope of selected design methods ............................................................ 22 3.2.1.1 Altshuller’s motivation and scope............................................................................................................ 22 3.2.1.2 Clausing’s motivation and scope ............................................................................................................. 23 3.2.1.3 Suh’s motivation and scope..................................................................................................................... 23 3.2.1.4 The Workshop Design Konstruktion (WDK) School’s motivation and scope............................................ 24 3.2.1.5 Discussion on scope of design methods ................................................................................................... 24 3.2.2 Approaches to develop new design methods ..................................................................... 24 3.2.2.1 Altshuller’s approach .............................................................................................................................. 24 3.2.2.2 Clausing’s approach................................................................................................................................ 25 3.2.2.3 Suh’s approach ....................................................................................................................................... 26 3.2.2.4 The WDK School’s approach .................................................................................................................. 26 3.2.2.5 Discussion on approaches to develop design methods .............................................................................. 27 3.2.2.6 Approach followed to develop the method presented in this thesis ........................................................... 28 4. EXPANDED FRAMEWORK OF INFORMATION IN DESIGN .......................................... 29 4.1 RESEARCH QUESTION ............................................................................................................. 29 4.2 RESEARCH METHOD ............................................................................................................... 29 4.3 LITERATURE STUDIES ............................................................................................................. 29 4.4 EMPIRICAL STUDY OF HOW ENGINEERING INFORMATION IS SYNTHESIZED IN A DESIGN PROJECT30 4.5 RESULTS ................................................................................................................................ 33 4.6 HYPOTHESES H1 AND H2 ....................................................................................................... 37 4.7 TESTING HYPOTHESES H1 AND H2 ......................................................................................... 37 4.7.1 Case study background ................................................................................................... 37 4.7.2 Effectively searching for potential design solutions.......................................................... 38 4.7.3 Design of the Depth Charge Initiator............................................................................... 39 4.7.3.1 Problem definition .................................................................................................................................. 39 4.7.3.2 Top level design...................................................................................................................................... 39 4.7.3.3 Decomposing the initiator (FR1) ............................................................................................................. 40 4.7.3.4 Environmental Analysis .......................................................................................................................... 40 4.7.3.5 Searching for DPs in the environmental phases ....................................................................................... 41 4.7.3.6 Choosing DPs. ........................................................................................................................................ 43 4.7.3.7 Design of sub-systems............................................................................................................................. 44 4.7.4 Final comments on the case study .................................................................................... 45 4.8 CONCLUSION .......................................................................................................................... 46 5. MANAGING INFORMATION IN THE FRAMEWORK ...................................................... 47 5.1 RESEARCH QUESTION............................................................................................................. 47 5.2 RESEARCH METHOD............................................................................................................... 47 5.3 THEORY DEVELOPMENT......................................................................................................... 47 5.3.1 Finding problem sources in a design object ..................................................................... 48 5.3.2 Proposing an information system for field service............................................................ 51 5.3.3 Tracing the impact of an Engineering Change Order (ECO)............................................ 51 5.3.4 Tracing design decisions.................................................................................................. 53 5.4 COMPUTER SYSTEMS THAT REALIZE SOME OF THE FUNCTIONS IN THE ABOVE THEORY............ 54 5.4.1 Background ..................................................................................................................... 54 5.4.2 Design information system based on axiomatic design ..................................................... 56 5.4.2.1 Analyzing the design process and information flows ................................................................................ 56 5.4.2.2 Finding existing tools that satisfy the requirements ................................................................................. 57 5.4.2.3 Implementation - Case study ................................................................................................................... 57 5.4.3 QCAD - Quality Computer Aided Design......................................................................... 64 5.4.4 Discussion on the differences between the two computer implementations........................ 66 5.5 CONCLUSIONS .......................................................................................................................