Is designing independent of domain? Comparing models of engineering, software and service design

Abstract

This paper presents a quantitative method for analysing process models of designing independently of the specific design domain. The method uses the situated function–behaviour–structure framework as the basis for a simulation model of a designer acting according to these models. The results of these simulations are sequences of design issues that are analysed using cumulative occurrence graphs with associated quantitative measures. The paper illustrates the approach by analysing and comparing three models of designing from different domains: Pahl and Beitz’ model of engineering design, the rational unified process of software design and a model of design for six sigma in service design. The quantitative results indicate some commonalities across the different models. These commonalities are related to the start of cognitive effort spent on design issues, the continuity of the cognitive effort throughout the design process and the constancy of the speed with which design issues are generated.