Expert systems in the design process

Computers have been used to aid the design process for well over twenty years. Initially there were just draughting systems, but now 3-D modellers and finite element analysis packages are commonplace. As computing power has become cheaper to buy and smaller to house so the applications for these systems have proliferated and all designers are now taking an interest. Expert systems, which try to imitate human decisionmaking capability, are much newer, but as with the draughting and analytical tools they will eventually find their way into the world of computer-aided design. This article discusses the possible roles of expert systems in the design process and illustrates the use of two shells - TIMM and INSIGHT - in relation to detailed design decisions. Using a shell will impose constraints on the way the problem must be formulated and the application of TIMM to the costing of turned components and INSIGHT to the selection of a manufacturing process demonstrate the kind of structures it will be necessary to use.