Optimizing dynamic performance of phased-mission systems with a common bus and warm standby elements

Phased-mission systems widely exist in many real-world systems such as communication networks, aerospace and unmanned aerial vehicles. The reliability modeling and analysis of phased-mission systems is highly important due to their indispensable roles in the society. Reliability analysis of a phased-mission system is challenging because of the statistical dependencies between different phases and the dynamic behaviors of system components. This research considers a phased-mission system with a common bus and warm standby elements. Each unit of the phased-mission system consists of n binary-state nonrepairable elements that are configured as a 1-out-of-n: G warm standby system. A recursive algorithm is proposed to determine the performance of the stochastic process with arbitrary time-to-failure distributions. A reliability evaluation algorithm based on the universal generating function is proposed to analyze the average instantaneous availability of the considered system. We further study the optimal system design problem that aims to find the optimal elements allocation as well as the optimal activation sequence to maximize the average instantaneous availability. A case study of a supervisory control and data acquisition system is presented to illustrate the application of the proposed model and algorithms.