Abstract
Today, developing various types of products in a short design lead-time is needed to satisfy consumers' needs. In this study, a method to support expansion of design requirements using product cases is proposed. In our previous reports, framework for expansion of design requirements was proposed and a supporting system was developed based on the framework. In this paper, we focused on the requirements cope with the influences of usage environment. First, descriptions of relations between a product and usage environment of it is defined based on product cases analysis. Then, a method to extract the design requirement cope with usage environment on the analogy of similar product cases is proposed. Finally, case studies were done using the system. The results showed that the system can extract the design requirements arise from usage environment.