A case study in a two-stage hybrid flow shop with setup time and dedicated machines

In this paper we address a scheduling problem taken from a label sticker manufacturing company. The production system is a two-stage hybrid flow shop with the characteristics of sequence-dependent setup time at stage 1, dedicated machines at stage 2, and two due dates. The objective is to schedule one day's mix of label stickers through the shop such that the weighted maximal tardiness is minimized. A heuristic is proposed to find the near-optimal schedule for the problem. The performance of the heuristic is evaluated by comparing its solution with both the optimal solution for small-sized problems and the solution obtained by the scheduling method currently used in the shop. As the heuristic is beneficial to the company, it will be implemented in the near future.