步加寿命试验下数控系统可靠性评定方法研究

通过温-湿双应力加速试验,优化设计数控系统可靠性评估的双应力加速退化试验,降低了试验费用、缩短了试验周期;采用双应力加速退化模型,丰富试验数据,根据数控系统竞争失效的特点,建立可靠性评估模型;针对失效数据小样本的特征,采用Bayes方法对模型参数进行评估,提高评估准确度。

Investigation on Rapid Evaluation of NC System Under ALT

We established the two stress acceleration model which based on temperature-humidity double stress step life test;considering that the failure data is mixture of censored data and complete data,we adopt the mixed data regression method to estimate the parameters of acceleration model;considering that the failure model for the numerical control system has many situation,we established competing failure reliability evaluation model.Consider that the failure data has the feature of small sample;we use historical information by bayes method for prior distribution and combined with step-stress test competition model to evaluate the model parameters and raise assessment precision.