Reliability evaluation of PMS considering coupling effect of functional and physical dependency

Aviation and aerospace system are typical Phased-Mission Systems (PMSs) featured with varying configuration, phased load condition and cross phase failure correlation. The coupling effect of Functional Dependency (FDEP) and Physical Dependency (PDEP) has a unique influence on the failure behavior of PMS. In this article, the coupling effect is analyzed, and the degradation of components is modeled with the positive drift wiener process, in which the drift coefficient is related to environmental conditions and operation stress. Finally, failure behavior and system reliability are simulated. An avionics controller is studied as a case, with the degradation time distribution model and simulation algorithm, the coupling effect and dynamical system reliability can be achieved. Results show that this modeling method can describe the coupling effects of FDEP and PDEP and their influence on the failure behavior and reliability of the PMS system.