Optimal Design of Accelerated Degradation Failure Mechanism Consistency Discriminant Test Based on D-Optimality

Abstract

Accelerated degradation test (ADT) is considered as a method for obtaining product degradation data in a short period of time, and the life and reliability of the product are inferred under the conditions of use.In order to ensure the effectiveness of ADT, guaranting that the failure mechanism of the product under each accelerated stress is consistent with the failure mechanism under normal stress is necessary. Therefore, it is necessary to carry out an accelerated degradation failure mechanism consistency discriminant test. At present, the determination of the test variables in the accelerated degradation failure mechanism consistency discriminant test is mainly based on experience, and lacks a set of experimental optimal methods with theoretical basis. In this paper, in order to solve the above problems, save sample capacity and reduce testing time, D-Optimality for step stress is applied to optimal design of accelerated degradation failure mechanism consistency discriminant test based on Wiener process.First, we apply Wiener process to describe an accelerated degradation failure mechanism consistency discriminant test. Then, we apply D-Optimality for step stress that by using the expenditure function and the decision variable function as restrictions, the sample capacity, the optimal total test time and the optimal time at each stress level are given. At last, a case study is used to illustrate the proposed method.