Mission abort strategy for generalized k-out-of-n: F systems considering competing failure criteria

For safety-critical systems such as submarines and solar lighting system, mission abort is an effective way to enhance system survivability when a certain malfunction condition is met. This paper contributes by presenting a bivariate mission abort policy for generalized k-out-of- n: F systems that fail if there are at least m non-overlapping k c consecutive failed components or at least k t failed components. When the number of non-overlapping k c consecutive failed components reaches a preset level or the total number of failed components exceeds a predetermined value, the mission is aborted, and then a rescue procedure is initiated. Mission reliability and system survivability are derived by employing a two-step finite Markov chain imbedding approach. The optimization models are formulated with the purpose of maximizing the mission reliability, and minimizing the expected total cost of mission failure and system failure, respectively. A numerical example based on a solar lighting system is presented to illustrate the applicability of the proposed policies.