Representation of similarity and dependency for assembly modularity

Researchers have expanded the definition of product modularity from function-based modularity to life-cycle process-based modularity, and developed a measure of product modularity and validated a corresponding modular product design method. However, a correct modularity measure and modular design method are not enough to realize modular product design. How the measure and design method are used, especially the role of product representation, is an important aspect of modular design and imperative for realizing the promised cost savings of modularity. In this paper, we develop a representation that includes similarity and dependency for assembly modularity. The similarity representation is based on assembly cost factors including tool changes and fixture changes. The process-based design dependency representation is based on design features that impact the assembly process (faces, fasteners, assembly interference, etc.). This representation captures the cost benefits of modularity and can be extended to other life-cycle processes. A set of products is used to show the application of this representation in association with a modularity measure and modular design method.