Dendrogram-directed design space exploration for DSM-based product modularization

Product modularization is an architecture design scheme for a product to manage its complexity as a system. The design methods for modularization often employ mathematical operations to achieve better modularization. Although multiple objectives result in various alternatives, identifying the superior one best suited for their trade-off relationships and ambiguity in their interpretation is challenging. Moreover, the decision-maker is required to explore the design space and determine the preferred solution with a rational reason. This study proposes a decision support method for product modularization based on the design structure matrix (DSM). The method is directed by the hierarchical clustering of alternatives into a dendrogram, and it facilitates the interpretation of alternatives over a decision bifurcation diagram. It is assumed that an optimal solution can be represented as a piling-up of smaller pieces, which correspond to building blocks in the combinatorial solution space. The distance of alternatives was surveyed using schema representation defined in various levels. Further, the hierarchical clustering technique structures the design space of alternatives into branches and organizes the essential parts, identified as building blocks, into a tree-shaped graph. Consequently, such a structure is crucial to revealing the leverage points in modularity and facilitates the exploration of product modularization. The proposed method was applied to an air-conditioner unit to demonstrate and ascertain its validity and effectiveness.