Real-time operational control of an FMS with full routing flexibility

This paper considers the operational control of an FMS with flexible alternative machines and flexible alternative operation sequences (full routing flexibility). Several policies are presented which can select in real-time the next operation for a part, and the machine to perform that operation, given that flexible process plans are available. These policies were examined by simulation of an eight-machine FMS model under several operating conditions against several performance measures. Results indicate that the system performance is at its best using a policy which seeks to balance the workload between machines while also minimising the distance travelled by the parts.