Failure Mode and Effects Analysis Using Rough Set Theory and Grey Relational Projection Method

Failure modes and effects analysis technique (FMEA) is One of the high usage tool to identify and prioritization of risks in the industrial, production and service environments. traditional FMEA has many shortcomings, Therefore many researches have been done to enhance the performance of FMEA. Also, in this study, a new approach has been proposed to deal with shortcomings of traditional FMEA. In this new approach Rough numbers have been used for representation of vague and subjective information and an improved method of gray relational analysis (GRA) as the Gray relational projection method (GRP) to prioritize potential failure modes. In the proposed method, evaluation of risk factors by members of the FMEA team has been modeled by Rough numbers and then The GRP method determines the priority of failure modes. To illustrate the performance of the proposed method, an example is used for the ranking of failure modes and evaluating and comparing the proposed model. The new approche have been overcame the shortcomings of traditional FMEA like multiplication of risk factors and the resulted discontinuous amounts and inattention to the weight of risk factors, by considering the weight of risk factors and using a method of prioritization by using GRP method. The proposed approach is achieved more affective and more accurate prioritization by covering ambiguity and uncertainty in experts’ judgements. The results indicates that in comparison with the traditional FMEA, a more reasonable and more accurate ranking have been resulted for FMEA method by combination of Rough numbers and GRP method.