Abstract
Industrial designers are new-creating both function and attribute of product in the conceptual design process. Quality of product depends heavily on their creative thinking. Therefore, it is difficult that computer-aided system supports a creative and inventive thinking process. We proposed the methodology of Conceptual and inventive Design Support System (CDSS) for its difficulty and estimated this methodology to satisfy the requirement. In this paper, we propose new analysis model by using contact and observer objects into use case diagram for CDSS, and estimate this model by questionnaire and rough sets. Furthermore, we experimented by adopting psychology about the estimation of the guidance method of using observer object. The validity is discussed thought the result of them.
