Due to the development of sensor technologies nowadays, condition-based maintenance (CBM) programs can be established and optimized based on the data collected through condition monitoring. The CBM activities can significantly increase the uptime of a machine. However, they should be conducted in a coordinated way with the production plan to reduce the interruptions. On the other hand, the production lot size should also be optimized by taking the CBM activities into account. Relatively fewer works have been done to investigate the impact of the CBM policy on production lot-sizing and to propose joint optimization models of both the economic manufacturing quantity (EMQ) and CBM policy. In this paper, we evaluate the average long-run cost rate of a degrading manufacturing system using renewal theory. The optimal EMQ and CBM policy can be obtained by minimizing the average long-run cost rate that includes setup cost, inventory holding cost, lost sales cost, predictive maintenance cost and corrective maintenance cost. Unlike previous works on this topic, we allow the use of continuous time and continuous state degradation processes, which broadens the application area of this model. Numerical examples are provided to illustrate the utilization of our model. Condition-based Maintenance Economic Manufacturing Quantity production time of the manufacturing system degradation state of the manufacturing system at t failure threshold of the degradation process X(.) first passage time of X(.) over H control limit of X(.) first passage time of X(.) over C pdf of TC pdf of TH under the condition that TC =tc operational time including production time and idle time on-hand inventory level at time t’ demand rate production rate production quantity/lot size production time for a lot number of lots produced random duration of corrective maintenance cdf of corrective maintenance time S pdf of corrective maintenance time S constant duration of predictive maintenance cumulative production and maintenance cost until time t’ expected total production and maintenance cost per cycle expected length of a cycle setup cost per lot expected setup cost per cycle expected inventory holding cost per cycle holding cost per unit held in inventory per time unit cost of lost sales per unit expected lost sales cost per cycle expected predictive maintenance cost per cycle cost related to the predictive maintenance activities triggered by the control limit C after the production of a lot expected corrective maintenance cost per cycle cost due to the unexpected machine failure, including corrective maintenance cost, scrap costs due to the machine failure, costs of changing staff working schedule or transportation schedule, etc average long-run total cost rate 
Joint optimization of condition-based maintenance and production lot-sizing