A Simulation Approach to Hybrid Flowshop Scheduling Using Dispatching Rules

Abstract

This research addresses a hybrid flow shop scheduling problem using a simulation approach. The scheduling problem is characterized by two features—blocking scheduling and sequence dependent setup time. The objective of the scheduling is to minimize the makespan, i.e. the time needed to complete all jobs. Different dispatching rules have been evaluated and their relative performances have been compared. The experimental results indicate that the commonly good dispatching rules in usual job shop scheduling like FIFO and SPT do not perform better or even much worse than LPT in the studied scheduling problem. The main reason is the special characteristic of the scheduling problem. Although this paper proposes some dispatching rules which perform well in minimizing the makespan, further researches are needed to find better dispatching rules for this kind of scheduling environment. The simulation uses the Flexism software as the coding and testing environment.