The dynamic 4S auto maintenance shop scheduling in a multi-constraint machine environment based on the theory of constraints

摘要

In this paper, 4S auto maintenance shop scheduling with multi-constraint machines is of concern. In 4S auto maintenance shop, it may appear temporary bottlenecks except for the long-term bottlenecks, and they form multi-constraint machines jointly with the task size reaching the peak. Through scheduling the constraint machines effectively, it can improve overall performance of the system to satisfy the customers' requirements. First, we describe and construct a model for the scheduling problem which can be designed as the dynamic flexible job shop scheduling problem (FJSP) with multi-constraint machines for the goal of minimizing customers' waiting time. Then, putting an emphasis on the constraint machines, we apply the theory of constraint to decompose and simplify the complex system and also construct the coordination mechanism between constraint machines and non-constraint machines. After that, an improved constraint-guided heuristic algorithm is proposed to solve the constraint machine scheduling problem, while different dispatching rules are selected for solving the non-constraint machine scheduling according to the location of the non-bottleneck in the system. What is more, we design the rescheduling rules combing characteristics of the problem to realize dynamic scheduling with multi-constraint machines. Finally, 4S auto maintenance shop scheduling with high workload during the rush hour (on the eve of the holiday) served as the actual cases, and the proposed algorithm is compared with three different dispatching rules under various size of problems. The result obtained from the computational study has shown that the proposed algorithm is much better.