A condition-based maintenance model for periodically inspected systems subjected to competing failure processes

Abstract

A condition-based maintenance model for periodically inspected systems subject to degradation and random shocks is addressed in this paper. Upon inspection, one will need to determine whether to perform a preventive maintenance, corrective maintenance, or to do nothing. In this paper, we present an expected maintenance cost rate model for systems subject to a degradation process and cumulative shock damage. An optimal maintenance policy consisting of two decision variables such as the preventive maintenance threshold and periodical inspection time, is determined that minimizes the expected long-run maintenance cost per unit time. To improve the search and better ways to obtain the optimum solution, we also propose a heuristic algorithm procedure based on the mean time to first failure concept in order to find the best optimum solution. A numerical example is given to illustrate the ideas of modeling and algorithms.