Optimal Periodic Maintenance Policy for Machines Subject to Deterioration and Random Breakdown

Optimal preventive maintenance (PM) policies for a machine subject to deterioration and random breakdown are derived using optimal control theory. PM policies are then obtained for a machine, and also for a group of i.i.d. machines working s-independently, subject to deterioration, intermittent breakdowns and associated repairs. The optimal policies are bang-bang. The PM ends when the income-rate from the machine becomes equal to the initial value of the income-rate.