Event-Driven Production Rescheduling in Job Shop Environments

Unpredictable incoming orders and the required nesting process highly complicate production planning and scheduling in sheet metal job shop environments and cause extremely high lead times as well as intermediate stocks. For this, numerous advanced planning and scheduling (APS) algorithms exist, aiming at creating a globally optimized production schedule. Due to the complexity of the multi-objective optimization and the large amount of unforeseen shop-floor events, effective and applicable solutions have not been presented so far. This work introduces an event-driven rescheduling concept based on lean principles leading to a high responsiveness of the production process to any kind of deviation. The achieved, significantly smaller buffer occupancies enable shorter lead times and improved delivery time estimations. Excellent performance results of the rescheduling concept are shown in different simulation experiments. The presented concept can easily be implemented in any kind of sheet metal job shop and its respective IT infrastructure.