Abstract:  Redesign is a work for improving a new product after it has been used a period. Identification of the redesign modules is the precondition. The existing identification methods mainly focus on customer demands, without considering product failure data. Therefore, a new identification method is proposed using fuzzy random FMEA. A redesign necessity index is defined to evaluate the design risk of product modules. Considering the randomness and fuzziness of the risk judgment, a fuzzy random FMEA model is constructed to measure the relationship between the failure modes and the product modules. Besides, credibility theory and fuzzy stochastic simulation technique are employed to deal with the multi valued problem of fuzzy variables and random variables. Finally, the feasibility and effectiveness of the proposed method is verified by the identification and verification of the crawler crane.

Key words:  redesign module identification, failure mode and effects analysis, credibility theory