Effort-saving modeling in the design process - results of a postal survey

In the design process the early stages of task clarification and conceptual design are important factors because of their determinant influence on the design costs. Observations of an individual designer's procedures show tha t finding ideas and generating solutions are largely associated with the us e of supporting external representations such as sketches and models. In a postal survey consulting 106 designers the extent and the effects of using such external representations were investigated. The results show the domin ance of sketches as an external aid and the increasing use of CAD already i n the early stages of the design process. Moreover, we found evidence of a close association between the supporting effects of external representation s and the communication processes of the designer with other persons involv ed in the design process.