随机环境应力冲击下基于多参数相关退化的导弹部件寿命预测

为了解决某型导弹部件的贮存寿命预测问题，提出了一种随机环境应力冲击下基于多参数相关退化的寿命预测方法。针对产品存在退化失效与突发失效两种失效模式，利用Wiener、Gamma及Inverse Gaussian等随机过程模型拟合各性能参数的退化数据，并采用Copula函数进行相关性退化失效建模；利用随机环境应力冲击解释突发失效的机理，并采用非均匀泊松过程对突发失效建模；进而建立退化失效与突发失效竞争的贮存寿命预测模型。实例应用说明所提方法能够反映出导弹部件的失效规律，比传统预测方法具有更高的预测准确性，具有较好的工程应用价值。

Lifetime prediction for missile components based on multiple parameters correlative degrading with random shocks of environmental stresses

In order to solve the problem of predicting the lifetime of a type of missile component, a prediction method based on multiple parameters correlative degrading with random shocks is proposed. The product has two failure modes which are degradation failure and traumatic failure. Some stochastic processes, including Wiener, Gamma, and Inverse Gaussian, are adopted to fit the degradation data of performance indexes, and Copula functions are then utilized to model the dependent degradation failure. The shocks of random environmental stresses are used to explain the mechanism of traumatic failure, and a non-homogeneous Poisson process is applied to model the traumatic failure. Thus, a lifetime prediction model is set up based on competing risks of degradation failure and traumatic failure. An application example validates that the proposed method, which can model the failure mechanism of the missile component, possesses higher prediction accuracy than traditional methods, and are applicable in engineering.