Real-Time resource allocations and shceduling of product-mix production systems with multi-type jigs

Abstract

This paper introduces an integration method for a multi-type resource allocation problem (MRAP) and Product-mix scheduling problems (PMSPs) in real-time. Particularly, SAR2 (Simultaneous Allocation based on Resource-Ratio) is used as high-speed heuristic approach for the MRAP, and an real-time scheduling method using optimal production cycle (OPC) is used in the scheduling to maximize the resource utilization while keeping a due date and Q-time restrictions of every production lot. As the result of performance evaluations in an actual wafer test process, the proposed method improved both the due-date satisfaction by 24.4–26.2% and standard deviation of tool utilization by 13–16%. The computational time was short enough for a real-time control even by using a standard personal computer.