Joint component-system maintenance planning over entire system task profile

Engineering systems have become increasingly complex, which demands the study of system-level maintenance strategy to be integrated with a realistic prediction of component-level performance. Most previous research of system maintenance models has focused only on the relationship between component failure rate and maintenance cost. For a system with degrading components, however, it is more intuitive to model the system’s health state together with component degradation processes. In this paper we propose a preventive maintenance strategy based on the simulation of component degradation processes and lifetime predictions. In addition, the proposed strategy utilizes the maintenance opportunities between tasks assigned by system. Specifically, the unit-time system maintenance cost is minimized with the consideration of interactions between component-level and system-level decision-makings. The approach we propose is more practical due to the simulation of the component degradation processes according to the real task profile of the system and the initial maintenance schedule can be re-adjusted in the event of an unexpected component failure. Therefore, it ensures an overall low maintenance cost and high system reliability over time. A case study of unmanned aerial vehicle illustrates the proposed method.