Failure mode and effect analysis using interval type-2 fuzzy sets and fuzzy Petri nets

Failure mode and effect analysis (FMEA) is a powerful reliability management tool for identifying and eliminating known and potential failures in systems, designs, processes, or services to improve their safety and reliability. At present, FMEA has been widely used in various industries. However, the traditional risk priority number (RPN) method has been criticized for many defects. For example, it ignores the relative importance of the risk factors severity (S), occurrence (O), and detection (D), and it is difficult for experts to evaluate the risk of failure modes using precise values from 1 to 10. In this study, we develop a new FMEA model that combines interval type-2 fuzzy sets (IT2FSs) and fuzzy Petri nets (FPNs) to overcome the drawbacks and improve the effectiveness of the traditional FMEA. The rationality and accuracy of the proposed FMEA are illustrated by an example of aerospace electronics manufacturing project. The results show that the new risk assessment model can produce more reliable and reasonable risk ranking results of failure modes in the practical application.