Reliability Evaluation of Nonlinear Degraded Equipment based on Wiener Process

In unstable environments, many devices exhibit non-linear degradation characteristics, and their degradation rate will also change accordingly. In order to consider the degradation differences between individuals, We introduce a method for evaluating equipment reliability in the context of nonlinear degradation, leveraging the Wiener process. This technique utilizes the Wiener process to depict equipment degradation and employs a time scale model to linearize nonlinear data. At the same time, the drift coefficients of the Wiener process were randomized to propose a reliability model that considers individual differences. The unknown parameters in the model were determined by using two-stage maximum likelihood estimation, and the correctness and superiority of this method were verified through examples.