A New Condition-Based Maintenance Decision Model for Degraded Equipment Subjected to Random Shocks

For the condition-based maintenance decision of the degrading equipment, the existing methods usually only consider the impact of maintenance activities on equipment degradation rate or degradation level, ignoring the impact of shocks existing in the life cycle. Toward this end, this paper concentrates on how to make optimal maintenance decision policy for degraded equipment subjected to random shocks under imperfect maintenance. Firstly, we propose a multi-stage degradation model based on the Wiener process and incorporate the influence of shocks and maintenance into the degradation model. The remaining useful life(RUL) is predicted under the concept of the first hitting time (FHT). Secondly, we establish a condition-based maintenance decision model on the basis of the prognostic information and determine the monitoring interval and the preventive maintenance (PM) threshold. Finally, a numerical simulation is provided to substantiate the condition-based maintenance decision model proposed in the paper.