Cased-Based Reasoning Based on Extension Theory for Conflict Resolution in Cooperative Design

Customer participation is common in cooperative design, which facilitates the understanding and addressing of customers’ requirements. Case-based Reasoning (CBR) is an effective method for quickly finding cases that may address customers’ requirements. The challenges for applying CBR to fulfill customers’ requirements at an early design stage include the complexity of requirements representation, the conflicts between different requirements, and the development of similarity measures for retrieval. This paper presents our work on the representation of both qualitative and quantitative requirements on product performance on the basis of fuzzy matter-element. On that basis, a similarity measure is developed using the side-distance in extension theory, to achieve accurate retrieval and effective conflict resolution. A case study of a screw air compressor is used to evaluate the proposed description method and the similarity measure. It is shown that the proposed methods are viable and effectively address the conflict resolution issue.