The Construction of Master Production Scheduling System and Available-to-Promise Mechanism under Process Selectable Environment for the TFT-LCD Cell Assembly Factory

摘要

TFT-LCD cell assembly factory takes charge of assembling the glasses from array factory with the color filters, and traditionally adopts hot press (HPS) process for filling liquid. With the introduction of one drop fill (ODF) process for accelerating the speed of filling, the production planning needs to consider the allocation of production quantities to two kinds of processes, according to customer's selection. Each product has three kinds of attributes including size, liquid type and process type, and every workstation takes account of some attributes to decide the setup time. With consideration of the uncertainty of actual orders, factories take make-to-order (MTO) mixed with make-to-forecast (MTF) policy and try to keep some unused capacity for satisfying the new arrived customer orders in the process selectable environment. As a result, this paper proposes a master production scheduling system to plan a schedule with the most unused capacity, and develops the available-to-promise mechanism to response the new arrived customer orders in short time. The proposed master production scheduling system is developed to solve the schedule for the polyimide print workstation and the bottleneck workstations of ODF process and HPS process simultaneously, with minimization of the bottleneck's setup time as the objective function. The available-to-promise mechanism is applied when the new orders arrive by checking the quantity available to promise and the capacity to promise first, and then reschedule for the new arrived orders. Experimental studies reveal that the proposed master production scheduling system allocates the production quantity of HPS process and of ODF process properly to raise the delivery rate, and the proposed available-to-promise mechanism can plan the new arrived orders fulfilled in seconds.