Fuzzy FMECA-Based Reliability Analysis of Welding Robots

A welding robot is an advanced piece of machinery in industry, especially in the field of industrial automation. As a complex system, it has a high failure probability because it manipulates, controls and performs complicated objects and tasks. Therefore, more attention has recently focused on the reliability of a welding robot. Reliability is very important because its performance will affect the overall system safety directly. In this paper we attempt to make the welding robot to be reliable and stable by using a fuzzy Failure Mode Effects and Criticality Analysis (FMECA) method. It is applied to determine the key to reliability improvement and maintenance of the welding robot system according to a failure model of hazard classes. Firstly, Failure Mode Effects Analysis (FMEA) of the key parts is carried out to obtain the failure modes. Secondly, the evaluation rules of the failure modes are discussed for experts scoring. Thirdly, the criticality of each failure mode is analyzed by fuzzy comprehensive evaluations. The analysis results are consistent with an actual situation and can verify the effectiveness of the presented method.