An Optimal Selective Maintenance Model for Multi-state Deteriorating Systems Considering Imperfect Maintenance

Multi-state systems, which widely exist in the industrial and military field, are usually required to execute a series of missions with a finite break between two adjacent missions. To improve the system reliability and guarantee the success of the next mission, selective maintenance strategy is proposed to identify a subset of feasible maintenance actions under limited maintenance resources. In this paper, a novel selective maintenance model for a series-parallel multi-state system consisting of multi-state components is developed to minimize the overall maintenance cost. The validity of the selective maintenance model is demonstrated via an illustrative example of an aircraft gas turbine engine system. A comparative analysis between perfect maintenance strategy and imperfect maintenance strategy is conducted, and the result indicates that the imperfect maintenance is more cost-effective than perfect maintenance.