Towards opportunistic maintenance
Résumé
Today most conventional maintenance strategies are purely reactive, corrective (fixing or replacing equipment after it fails) or time-scheduled (Wang, 2002). These strategies are not well adapted to the control of the global performances of a manufacturing system (Gupta, et al., 2001). Therefore it is now necessary to move from traditional maintenance strategies towards condition-based maintenance performed only when a certain level of equipment deterioration occurs, or predictive maintenance which anticipates the appearance of a failure (Djurdjanovic, et al., 2003). This notion of anticipation becomes of true importance whenever a prognosis process is available (Iung, et al., 2005). Indeed the notion of anticipation allows the investigation of non-planned maintenance actions, which is part of what is called opportunistic maintenance. Opportunistic maintenance aims at answering the following questions: When to perform a particular maintenance action? What components should benefit from a preventive maintenance action? Which components should first benefit from a preventive maintenance intervention? The notion of opportunistic maintenance has been carefully reviewed in (Thomas, et al., 2008a). It was emphasized that the classical notion of opportunistic maintenance can cover up various realities and criteria. Moreover predictive vs. proactive maintenance strategies may generate numerous opportunities to perform non-previously-planned maintenance tasks. The notion of opportunistic maintenance currently does not allow taking advantage of those new opportunities-to-come, partly because of the lack of rigorous definitions and adapted formalisms of opportunistic maintenance