When designing complex products such as robots or jet engines, companies face the problem that designers lack the necessary tools to predict the behaviour of the product in the case of component change, and to assess the risks associated with decisions. Product models allow companies and individual designers to reason about product properties. The information in the model can be used to analyse the properties of a product before decisions are taken about potential modifications. To meet time and budget constraints it is vital to have the ability to predict the risks of knock-on effects before a change is implemented and select alternative changes accordingly. This paper introduces a comparison of two product models used in the Change Prediction Method (CPM) and the Contact & Channel Model (C&CM). It analyses ways where both approaches can benefit and complement each other in analysing and predicting product change.@en

Functional product models in design so far were built up by asking for the main function of a product first and then breaking the main function down into sub-functions, until an appropriate level of granularity was reached. A problem of this approach is that a product often provides even more functions which are not subordinate to the main function. This paper presents an approach how these functions can be captured in a reliable and structured way, using the requirements of a product as a superstructure. The improvements of this new approach are demonstrated by predicting change propagation based on an improved functional product model and comparing it to the results of a change prediction using the conventional functional product model.@en