A layout technique for class diagrams to be used in product configuration projects

The use of product configurators has produced a range of benefits for several companies, such as minimizing the use of resources and shortening the lead times in product specification processes. When developing a product configurator, two kinds of models are often created, namely analysis models and design models. Since the task of describing product knowledge in analysis models involves domain experts, the analysis language has to be easily understandable in order to avoid the need for extensive training. For this task, the so-called Product Variant Master (PVM) diagramming technique is often applied. With regard to the design model, the requirements for the language focus more on a formalized and rich language, which is why class diagrams are often applied. To avoid the use of different modelling languages in the analysis and design phase, this paper proposes the layout technique 'Vertically Aligned Class Diagrams' (VACDs), which incorporate the usability of PVMs into class diagrams. To validate the usefulness of the VACD technique, the paper compares VACDs to PVMs and class diagrams in a utility analysis and a usability experiment. These investigations strongly indicate that VACDs maintain to a great extent the combined advantages of PVMs and normally drawn class diagrams. Thus, the use of VACDs in configurator projects has the potential to increase efficiency, improve communication and reduce errors.