基于竞争失效的导弹机电产品可靠性评估

目的 解决导弹机电产品退化-突发竞争失效模式下的可靠性评估问题。方法 对导弹典型机电产品电机进行贮存失效分析，同时考虑双参数退化失效和突发失效对电机贮存可靠性的影响。首先，以具有随机效应的非线性Wiener过程描述电机贮存退化失效过程中的非线性、随机性和样本差异性。然后，采用Weibull分布描述突发失效过程规律，并考虑退化程度对突发失效的影响。最后，利用Copula函数刻画退化性能参数之间的相互作用关系，建立双参数退化-突发竞争失效模型，并给出基于两步极大似然估计的参数估计方法。结果 以仿真导弹电机退化突发失效数据为例进行分析，实现了基于双参数退化-突发竞争失效模型的系统可靠性评估，得到电机贮存5 a时的可靠度估计值为0.465。结论 所构建的双参数随机退化与突发失效相关的竞争失效模型有效，为导弹机电产品可靠性验证评估及寿命预测提供了相应的理论依据。

Reliability Assessment of Missile Electromechanical Products Based on Competitive Failure

The work aims to address the reliability assessment problem of missile electromechanical products under the degradation-traumatic competitive failure mode. The storage failure analysis of typical missile electromechanical products was carried out, and the effect of multivariate degradation failure and traumatic failure on the storage reliability of the motor was considered. Firstly, a nonlinear, stochastic, and sample-specific degradation failure process in electromechanical products was described by a nonlinear Wiener process with random effects. Secondly, the Weibull distribution was adopted to describe the pattern of traumatic failure process, taking into account the effect of degradation level on traumatic failure. Finally, the copula function was used to describe the interaction relationship between the degradation performance parameters and a multivariate degradation-traumatic competitive failure model for electromechanical products was established. A parameter estimation method based on two-step maximum likelihood estimation was given. Taking simulated missile motor degradation and sudden failure data as an example, the system reliability assessment based on the multivariate degradation-traumatic competitive failure model was implemented, and the estimated reliability value of this product after 5 years of storage was 0.465. The constructed dual-variable stochastic degradation and traumatic failure competitive failure model is effective, providing a theoretical basis for reliability verification, assessment and lifespan prediction of missile electromechanical products.