基于可能性理论的随机应力加速寿命试验分析方法

An Approach for Analyzing Accelerated Life Test with Random Stresses Based on Possibility Theory

在加速寿命试验中,随机应力的影响是普遍存在的,但目前对随机应力条件下的加速寿命试验分析缺乏有效的方法。以可能性理论为基础,将随机应力转化为一个模糊应力,通过确定该模糊应力的可能性分布函数,建立随机应力条件下的寿命分布模型。提出一种通过求取模糊数的上、下可能性均值来减小模型误差的方法,并以阿伦尼斯模型为例,分析了温度随机应力条件下的寿命分布模型,结果证明该方法是有效的。

The influence of the random stress is ubiquitous in the accelerated life test, but it is difficult to analyze the accelerated life test under random stresses currently. An approach based on the theory of possibility was presented, which transformed the random stress into one fuzzy stress, and thus the lifedistribution model with the random stresses could be established by estimating the possibility distribution of the fuzzy stress. Then, a method was presented to reduce the model error by calculating the lower possibility and upper possibility mean values of fuzzy numbers. Finally, an example was taken based on the Arrhenius model, and the life-distribution model with the random temperature stress was analyzed. The result demonstrated the feasibility of this approach.