Reliability analysis of PMS with disconnected mission phases

Traditional phased mission system (PMS) requires that mission phases are connected one after another. However, there is a kind of PMS with mission phases that are not connected consecutively because of idle phase existing among them. Component repair can occur in idle phase, but there is no mission requirement in such phase. This is a new kind of PMS that has not been investigated thoroughly in literature. In this paper, mission reliability is defined as the probability that the system successfully complete missions in all phases except in idle phases. By define absorbing states as the failure states corresponding to the systems mission failure, a continuous time Markov chain (CTMC) models are built for each mission phase. The transition probabilities of system states are obtained by solving CTMC models. Based on these probabilities, mission reliability can be calculated for such kind of PMS. Finally, a numerical example is provided to show the effectiveness of the proposed approach.