Heuristic Model for Dynamic Single Machine Group Scheduling in Laser Cutting Job Shop to Minimize the Makespan

Abstract

In today’s highly competitive market, laser cutting which has a characteristic of “make to order” and high product variety is under pressure to reduce costs, to increase productivity and to respond to the rapidly changing demands from customers. To maintain the competitive advantage, companies need to have a real-time dynamic scheduling system, which can handle large combinations of jobs, allowing sequencing of jobs to achieve multi-objective goals. Motivated by a real-life scheduling problem in a sheet metal processing company in Malaysia, this research addressed single machine scheduling problem with sequence-dependent setup times and group technology assumption to minimize makespan and with the secondary objective of minimizing setup times. The focus of this paper is on developing a simple heuristic algorithm based dynamic scheduling system. This algorithm has been coded in vb.net and is integrated with a database system. The scheduling system developed is verified and validated by comparing to the actual production run. Results show that the algorithm model can find good solutions within short computational time.