Batch versus cyclic scheduling of flexible flow shops by mixed-integer programming

Abstract

New mixed-integer programming models are proposed for deterministic batch or cyclic scheduling in flow shops with parallel machines and finite in-process buffers. Models for scheduling with all machines continuously available for processing throughout the entire scheduling horizon as well as for scheduling with an arbitrary pattern of machine availability due to pre-scheduled downtime events are provided. Numerical examples modelled after real-world flexible flow shop scheduling in electronics manufacturing are presented, and to compare the batch and cyclic schedules with continuous or with limited machine availability, results of computational experiments are reported.

Keywords:

• flow shop scheduling
• mixed integer linear programming
• batch scheduling
• cyclic scheduling

Acknowledgements

This work was partially supported by a MNiSW research grant and by AGH. The author is grateful to two anonymous reviewers for comments that helped to improve the presentation of the paper.