Opportunistic condition-based maintenance and aperiodic inspections for the two-unit series system
Condition-Based Maintenance (CBM) intends to perform maintenance right before a failure occurs by estimating the pending moment of failure based on monitoring a certain condition, such as vibration or temperature. This paper considers a two-unit series system with economic dependencies. The aperiodic inspection moments are optimized simultaneously with the critical levels at which maintenance is performed in order to minimize cost and/or maximize availability. For this purpose, a stochastic model is developed based on semi-regenerative properties of the maintained system state. We build on the work of Castanier, B., A. Grall, and C. B_erenguer (2005), A condition-based maintenance policy with non-periodic inspections for a two-unit series system, Reliability Engineering & System Safety 87 (1), 109{120, by fully including all opportunistic maintenance opportunities, determining the system unavailability time more accurately, and providing a more extensive performance evaluation. Results indicate that the accuracy with which the unavailability time is approximated has a great impact on the resulting optimal maintenance strategy. Keywords: Condition-based maintenance, Multi-unit system, Economic dependencies, Aperiodic
inspections, Reliability