On the use of time-limited and monitoring information for maintenance decision support

Developments of monitoring techniques provide information on the actual conditions. The information level available on the system (failure times, deterioration, load, usage condition, etc.) and the way to integrate them impact directly the performance of maintenance operations that represent a substantial portion of the total life cycle costs of many systems. In this context, we consider a gradually deteriorating system operating under an uncertain environment. The information about the future environment state is only known on a finite rolling horizon. The system is subject to constraints and maintenance actions cannot be planned at any time, but at fixed times called maintenance opportunities and known only on a finite horizon. Based on the considered system, we aim to use the monitoring data and the time-limited information for maintenance decision support in order to reduce its costs. Several maintenance policies are proposed: age-based policy, condition-based policy and two predictive policies based on a cost and a risk criterions. The comparison of the maintenance cost savings of these policies allows concluding the value of different types of information and the best ways to use them in maintenance decision-making.