Constructive and composite heuristics for the 2-stage assembly scheduling problem with periodic maintenance and makespan objective

This paper addresses the 2-stage assembly scheduling problem to minimise makespan with availability constraints, where the machines are not always available due to periodic maintenance activities. To the best of our knowledge, the periodic maintenance constraint has never been considered for the problem under investigation. In the proposed model, the preemption of operations is not allowed, and therefore, if an operation cannot be finished within the current availability period, then it has to be completely processed in the next one. Firstly, two constructive heuristics powered by a partial local search mechanism are proposed. Secondly, two composite heuristics are proposed incorporating an interchange-based local search mechanism. After that, two computational evaluations are carried out. On the one hand, 84 dispatching rules adapted from the literature, involving two bin-packing policies, are compared among them. On the other hand, the proposed methods are compared with existing heuristics from the literature. The computational results show that the adapted dispatching rules perform well for the two bin-packing policies, and the new proposals outperform the existing heuristics.