Predictability of change in engineering

Abstract

Design changes can be surprisingly complex. We examine the problems they cause and discuss the problems involved in predicting how changes propagate, based on empirical studies. To assist this analysis we distinguish between (a) a static background of connectivities (b) descriptions of designs, processes, resources and requirements and (c) the dynamics of design tasks acting on descriptions. The background might consist of existing designs and subsystems, or established processes used to create them. The predictability of design change is examined in terms of this model, especially the types and scope of uncertainties and where complexities arise. An industrial example of change propagation is presented in terms of the background (connectivity) - description - action model.