An opportunistic maintenance model for multi-component systems experiencing shocks

Abstract

In various industrial fields, systems are often exposed to external or internal shocks, which can significantly affect their performance. This study proposes an opportunistic age-based preventive maintenance (PM) strategy for a multi-component coherent system whose components are exposed to fatal shocks. At the system’s initiation, a PM is scheduled at a set time (Formula presented). The system is subject to occasional fatal shocks, arriving in a random pattern resembling a counting process. If the system fails before (Formula presented), it will be restored to a new state by replacing the failed components and repairing the operating components to an “as good as new” state. If the system is functioning at time (Formula presented), the number of failed components is checked to decide whether the system should be replaced or allowed to continue operating. If the number of failed components at (Formula presented) is less than a threshold (Formula presented), the PM time (Formula presented) is postponed to a new PM time (Formula presented) and the system continues operating in the interval (Formula presented). Otherwise, a PM action is performed on the entire system by replacing the failed components and repairing the operating components to an “as good as new” state. Under this scenario, we integrate a cost function based on various cost parameters to determine the optimal values of decision variables (Formula presented), (Formula presented), and (Formula presented). In the particular case that the process of component failures is a non-homogeneous Poisson process, we examine the effectiveness of the proposed model by analyzing some examples of coherent systems using graphical and numerical methods . © IMechE 2025