Finding Breakthrough Points in Platformed Product Family Design

In product development, a design parameter, which designers can change directly, often has an adverse effect on several function metrics, which are indices that describe the product performance. This phenomenon is called a “tradeoff.” Traditionally, tradeoffs are considered for a single product. However, in recent years, there have been tradeoffs between several products because of communal design parameters in platform-based product family design. This problem makes it difficult to determine the point at which a technological innovation is profitable. In this paper, the point where designers make a technological innovation is defined as a breakthrough. A method is suggested to find the effective breakthrough point for a product family. A model was developed that shows the relations between design parameters and function metrics from a quality function deployment (QFD) to comprehensively estimate the effectiveness of a technological innovation. As an example application, a prototype system was developed and applied to searching a solar boat product family for breakthrough points. The results showed that the proposed method effectively supports the decision-making of product designers.