Modelling product representations used in automobile body design

Engineers use many different models in the course of their work, varying from physical models through graphical to mathematical and computational models. This paper describes a study of the automobile body-in-white design process to identify the models used in the course of this process. It explains the experimental method of using Petri net diagrams to describe the design process in an automotive company, and then using these models in conjunction with the company’s engineers to identify the models used by the engineers at each stage in the process. It will describe the overall use of models in the process, and also one particular aspect of the process in some detail, to illustrate the application of the experimental technique. Representations involve the initial use of sketches and stylists’ renderings, then the development of the body form through physical models. Specialist models are used for formability and structural analysis, and for the development of tooling. The paper concludes with some suggestions on the lessons to be learned for process modelling and computer support tools.