Operation management in reconfigurable manufacturing systems: Reconfiguration for error handling

Reconfigurable manufacturing systems offer quick adjustment of production capacity and functionality in response to unpredictable market changes as being systems designed at the outset for rapid change in system configuration, its machines and controls. During the production process, out-of-ordinary events occur dynamically and unpredictably both at the system (machine breakdowns, change in job's priorities, etc.) and at the cell level (tool failures, robot collisions, etc.). Such exceptions interrupt the production process by causing errors in the schedule plan (system level) or in the task plan (cell level). Error handling is the policy meant for reacting to errors caused by the occurrence of out-of-ordinary events. The reconfiguration ability turns out to be the new technological factor enabling new strategies to handle out-of-ordinary events of the production process. Both economic and performance aspects need to be considered in order to make a decision in support of particular error handling policies such as using reconfiguration. This paper, starting from a simulation case study, highlights advantage of using reconfiguration for error handling. Authors propose an object-oriented high-level control structure for real-time error handling, which integrates the new reconfiguration for error handling technology with the existing reactive scheduling system.