Dynamic scheduling of flexible manufacturing systems : a study of machine and material handling control strategies

In recent years there has been an increased interest in automated and Flexible Manufacturing Systems (FMS). The focus of this research is to develop and test on-line scheduling rules for both machines and material handling sub-systems of an FMS. The scheduling rules use various priority attributes and relevant information concerning the availability status of resources in the decision making process. These rules are dynamic in nature because the priority of a job in the system can change continually. The scheduling rules are applied to control a hypothetical FMS consisting of multiple shared resources for different operating conditions. Simulation is used to model the system and consequently test the performance of different scheduling rules with respect to mean flowtime, consistency of output, and efficient operation of the material handling system. Design of experiments is used to explore the relative effectiveness of scheduling rules on the system performance measures for a variety of experimental conditions