We consider the integrated problem of optimally maintaining an imperfect, deteriorating sensor and the safety-critical system it monitors. The sensor's costless observations of the binary state of the system become less informative over time. A costly full inspection may be conducted to perfectly discern the state of the system, after which the system is replaced if it is in the out-of-control state. In addition, a full inspection provides the opportunity to replace the sensor. We formulate the problem of adaptively scheduling full inspections and sensor replacements using a partially observable Markov decision process (POMDP) model. The objective is to minimize the total expected discounted costs associated with system operation, full inspection, system replacement, and sensor replacement. We show that the optimal policy has a threshold structure and demonstrate the value of coordinating system and sensor maintenance via numerical examples.

Additional Metadata
Keywords maintenance optimization, partially observable Markov decision process, sensor deterioration, threshold policy
Persistent URL dx.doi.org/10.1002/nav.21763, hdl.handle.net/1765/102727
Journal Naval Research Logistics: an international journal
Citation
van Oosterom, C. (Chiel), Maillart, L.M. (Lisa M.), & Kharoufeh, J.P. (Jeffrey P.). (2017). Optimal maintenance policies for a safety-critical system and its deteriorating sensor. Naval Research Logistics: an international journal, 64(5), 399–417. doi:10.1002/nav.21763