Optimization design method of step-stress accelerated degradation test

Abstract

The invention discloses an optimization design method of a step-stress accelerated degradation test, comprising the following steps of: firstly, determining a product performance degeneration model, an accelerated model and reliability functions; secondly, establishing an objective function; thirdly, determining a constraint condition and an optimization variable; and fourthly, realizing an optimization algorithm. When the asymptotic variance of the p quantile life reliability is calculated by using minimum asymptotic variance of p quantile life reliability as a target, the local derivation of the reliability function is solved by adopting a differential mode. The optimization design method solves the problems of seeking complicated function derivation difficultly, making a mistake easily, and the like. According to engineering experience, a constraint condition of monitoring times under any stress is supplied, a test optimizing result has an engineering actual significance, calculation times are greatly reduced by the restriction of M1.>=M2>= etc.>=Mk>=10, and the test optimization rate is increased. The test stress is used as the optimization variable, a stress level constraint condition is supplied according to practical conditions, and a test scheme can be systematically and roundly optimized.

Description

technical field [0001] The invention relates to an optimal design method for a step stress accelerated degradation test, belonging to the technical field of accelerated degradation tests. Background technique [0002] With the development of modern technology, there are more and more high-reliability and long-life products. In order to evaluate the reliability and life of these products, the American Roma Aeronautical Center formally proposed the accelerated life test (ALT) in the 1960s. At present, ALT Technology research has achieved a lot of research results, but long-life and high-reliability products have only a small amount of failure or no failure in ALT, which brings great difficulties to product life and reliability evaluation. To solve this problem, accelerated degradation test (ADT) came into being. ADT overcomes the deficiency that ALT only records product failure time without considering product performance degradation. By processing accelerated degradation dat...

AI Technical Summary

Problems solved by technology

[0006] So far, in the research on the optimal design of the SSADT scheme, the optimal design variables have not included the test stress level, and the test optimization is carried out under the condition of a given test stress level. In the optimal scheme, only test samples, monitoring frequency, and test censoring Time or number of monitoring

Images