Modeling dependent competing failure processes based on stochastic hybrid systems

Complex systems and products are usually subject to multiple dependent competing failure processes (DCFP). Modeling of such systems are widely researched in recent years. In this paper, we adopt a new approach to model DCFP based on a class of stochastic processes referred to as stochastic hybrid systems (SHS) to achieve better computational performance. The developed SHS-based DCFP model considers soft failures caused jointly by continuous degradation and additional abrupt degradation increment due to random shocks, and hard failures caused by sudden overload from the same shock processes. Failures occur whenever one of the following two events happens: (i) the degradation process reaches its threshold; (ii) a shock whose magnitude exceeds a critical strength level occurs.