Reliability Assessment Method Based on Performance Degradation and Improved Dempster-Shafer Evidence Theory

In view of the difficulty of the traditional reliability evaluation method for multivariate performance parameters, this paper puts forward a kind of reliability assessment method which is based on performance degradation and Dempster-Shafer (DS) evidence theory. Firstly, the degradation data of each performance parameter is modeled, and their degradation models and life distributions are obtained. Secondly, a distance function of Jousselme is introduced to modify the traditional evidence theory to improve the processing ability of the conflicting evidence information. Thirdly, the improved DS evidence theory is used to fuse and make decisions on life data of each key performance parameter, and then the overall reliability index of the product can be obtained. Finally, this method is tested with performance degradation data of fiber-optic gyroscope and the storage life of it is 38,000 hours. The experimental result shows that this method is more reasonable and accurate for reliability assessment of multivariate performance parameters of fiber-optic gyroscope and has certain reference value for maintenance support decision of equipments. It is also applicable to the reliability assessment of other equipments.