Multi-objective joint optimization of batch-discrete hybrid flow shop scheduling integrated with machine maintenance

Many studies on production scheduling are focusing on production line composed of same type of machines. However, multiple processing form are existing in real production environment. And preventive maintenance and emergency repair cause the unavailability of machine will affect production efficiency. In order to solve the conflict between dispatch schedule and preventive maintenance plan. This paper develop a joint optimization on a hybrid flow shop model including not only batch processor but also discrete processor. And a preventive maintenance strategy based on reliability is designed. The multi-objective is to simultaneously minimize the makespan and total production cost. Particle swarm optimization and heuristic algorithm are proposed to solve the problem. Then a large number of computational instances are conducted. The experimental results show that joint optimization are superior compared with independent decision-making. And it also show the effects of different unit production cost for batch size in the end.