Reliability Analysis Approach for Variation by Integrating FMEA with VMEA

This paper describes a reliability analysis approach which is called F-VMEA. Traditional FMEA is insufficient to consider detrimental variations which lead to soft failure, so, the proposed F-VMEA compensates for the deficiencies. Hence, the objective of this article is to show how to simultaneously consider failure and variation in whole product development process. F-VMEA starts with FMEA and processes in parallel with VMEA, hence can derive significantly cooperative effect for predicting system reliability finally. During the concept design phase, integrating FMEA with basic or enhanced VMEA is reasonable and effective for limited information. With the data, information and knowledge increased, the FMECA is combined with probabilistic VMEA in the detailed design stage. This approach not only concentrates on failure but also fully pays more attention on unwanted variation, then, the causes which lead to soft or hard failures can be roundly founded in the design stage. This paper outlines the detailed implementation process of F-VMEA. The feasibility of this method is demonstrated by specific steps of implementation. Finally, the jet pipe electrohydraulic servo valve is used to verify the F-VMEA method.