Representing product architecture and analyzing evolvable design characteristics
There is a strong connection between a product’s architecture and the ease with which it can be evolved into future generations of products. The main goal of this dissertation is to create a measurement tool that can assess the extent to which a design exhibits different characteristics of being flexible for future evolution. The High Definition Design Structure Matrix (HDDSM) is presented as a product representation model that captures the specific types of interactions between components of a product. An interaction basis is defined that extends the detailed flows of signal, material, and energy used in functional modeling to include detailed spatial interactions. By including an external element to represent all interactions that cross outside of the product boundary, the HDDSM is shown to be a modular product model. A process for reverse engineering products and creating a HDDSM is presented and shown to significantly reduce the effort required to create a HDDSM model. The repeatability of the HDDSM model is evaluated by calculating the interrater agreement between models created by independent examiners.
Four analysis processes are presented to analyze the HDDSM model for characteristics of evolvable design. These characteristics are taken from design guidelines for product flexibility for future evolution. The analyses produce quantitative metrics that allow an examiner to measure and compare how well a particular characteristic of evolvable design has been incorporated based only on the component interactions recorded in the HDDSM. Three of the metrics, the Space Potential Ratio, the Framework metric, and the Energy-Flow Module metric are shown to be consistent with a product’s flexibility for future evolution as measured by a Change Modes and Effects Analysis.