ECDEX: A knowledge-based approach to conceptual design of engineering systems

Abstract

This paper describes a knowledge-based approach to the domain independent conceptual design phase. We describe the development of “ECDEX”, the “Engineering Conceptual Design Expert” that generates concept variants (concept alternatives) during the conceptual design phase of engineering systems. ECDEX was developed using an expert system shell called CLIPS (C Language Integrated Production System) and a C-program interface to aid the quantitative phase of concept evaluation. ECDEX internally develops function structures that are dependent on the number of solution principles for each sub-function selected during the process. After the function structures are developed, ECDEX searches for solution principles for each of the sub-functions considering that every combination needs to begin with the system input and end with the system output. After all combinations are developed, ECDEX performs the concept evaluation using evaluation criteria defined by the designer providing a set of ‘concept variants’. ECDEX is applied to three test cases; an impulse loading test rig, a hydro-electric generation plant and a fishing reel. The results from these three test cases demonstrate that ECDEX generates satisfactory conceptual designs of engineering systems.