Machine-based production scheduling for rotomoulded plastics manufacturing

Abstract

In this paper, production scheduling for rotomoulded plastics manufacturing in a multi-machine environment is considered. The objective is to minimise total tardiness. The problem has some commonality with hybrid flow shop scheduling with batching, where additional constraints are needed to control which machines may be used at each stage. The problem is shown to be NP-hard and is formulated as a mixed integer program. Given consequently large solve times to obtain optimal solutions, simulated annealing and tabu search algorithms were developed alongside a constructive heuristic to obtain near-optimal solutions within a practical time-frame. The solution algorithms were tuned and tested using randomly generated problem instances. The best results in terms of solution quality were generally obtained by simulated annealing. The problem instances were generated to be representative of a real production environment located in Queensland, Australia.

Keywords:

• rotational moulding
• scheduling
• metaheuristics
• mixed integer programming

Acknowledgments

Industry partners Global Roto-Moulding provided historical production data to inform model testing. Computational resources and services used in this work were provided by the High Performance Computing and Research Group at the Queensland University of Technology.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Mark Baxendale http://orcid.org/0000-0002-1920-3217

James M. McGree http://orcid.org/0000-0003-2997-8929

Paul Corry http://orcid.org/0000-0003-3313-5967