Research On Reliability Modeling And Evaluation Based On Performance Degradation Data For Fiber Optic Gyroscope

The fiber optic gyroscope(FOG)is a typical electromechanical coupling product with high reliability,long life and small sample,which is widely used in the field of inertial navigation.As the key part of the inertial navigation system,the reliability of FOG becomes one of the key performance indexes.Therefore,how to model and analyze its reliability is of great significance.Because of the characteristics of high reliability and long life,it is difficult to get effective results by traditional failure life data.However,the failure mechanism of products shows that the degradation process of products contains a wealth of product reliability information,which can well reflect the performance characteristics of products.The reliability of FOG can be ensured by modeling the reliability of the product and evaluating the reliability of the product according to the data of the degradation process.Therefore,in this paper,performance degradation theory is used to study the reliability of FOG.The thesis mainly includes the following:(1)The structure,working principle,relevant performance indexes and the main characteristics of FOG are described.The degradation failure types and degradation failure mechanism of FOG are analyzed,and the related reliability theory is introduced.(2)The reliability evaluation model of FOG based on single performance degradation is constructed.The theory of reliability research based on performance degradation data is described.By modeling and analyzing the performance degradation process of FOG,the Wiener process is used to describe the performance degradation process of FOG,and the maximum likelihood estimation method is used to estimate the parameters of the model.Finally,the validity of the model is verified by the performance degradation data of FOG.(3)A reliability evaluation model of FOG based on multiple performance degradation is constructed.Firstly,the reliability model of single performance degradation index is built by Wiener stochastic process;Then the reliability model is built for the multi-element performance characteristic.Based on the accurate description of the correlation among the performance indexes,using the advantage of Copula function to describe the correlation among the multi variables,a multi performance reliability evaluation model of FOG is constructed,,and two step synthesis method is proposed to select the optimal copula function model.Finally,the validity ofthe model is verified by the data example of FOG.