A Probabilistic Design Reuse Index

The benefits of being able to create a number of product variations from a limited range of components, or sub-assemblies, are widely recognized. Indeed it is clear that companies who can effectively reuse elements of existing designs when creating new products will be more productive and profitable than those whose catalogues are full of parts individually tailored to specific models. Frustratingly, despite the benefits, existing approaches to quantifying the amount of design reuse within a company’s product range are laborious and often provide only aggregated reuse value that provided little explicit indication of where the highest and lowest levels of re-use occur within a product portfolio. This paper surveys existing measures of design reuse and describes the results of applying some of them to quantify the amount of commonality in a range of flat-pack furniture. The results illustrate the differences between their definitions of design reuse. We then present a new approach to objectively quantifying levels of reuse by comparing actual probability distributions of component use with virtual ones, where every component is used with equal preference. The proposed reuse metric, named Probabilistic Design Reuse Index (PDRI), is applied to the flat-pack dataset and the results used to highlight component families with low levels of design commonality.