Adjusting condition monitoring quality for condition-based maintenance optimization of deteriorating systems
Proceeding of 9th International Conference on Modelling in Industrial Maintenance and Reliability 2016
Condition monitoring (CM) is an essential part in a condition-based maintenance (CBM) program as it can provides useful information about the system health for maintenance decision-making. The quality of CM information depends closely on implemented inspection and instrument technologies, and eventually on invested costs. While numerous works in the literature have considered problems related to CM quality (e.g., imperfect inspection models, detection and localization techniques, etc.), few of them focus on adjusting CM quality for CBM optimization. In this paper, assuming that the quality of CM information can be controlled by adjusting inspection costs, we investigate how such adjustment can contribute to save on the total cost of a CBM program. The study is done for a single-unit deteriorating system subject to random failures and to periodic inspection. We model the quality of the degradation information on the inspected system using the idea that its variance is a decreasing function of inspection cost (i.e., a more accurate CM information requires a more sophisticated inspection, hence a higher cost). A new inspection and replacement strategy whose decisions are adapted to this variance is proposed and compared to a non-adapting classical one. The comparison results under various configurations of system characteristics and maintenance costs allow us to conclude on the interest of CM adjustment in CBM optimization.