This paper proposes new algorithms for the assembly line balancing problem with hierarchical worker assignment (ALBHW). The ALBHW appears in real industrial contexts where companies deal with a multi-skilled workforce. It considers task execution times that vary depending on the worker type to whom the task is assigned. Qualification levels among workers are ranked hierarchically, where a lower qualified worker costs less but requires larger execution times. The aim is to assign workers and tasks to the stations of an assembly line, in such a way that cycle time and precedence constraints are satisfied, and the total cost is minimized. In this paper, we first present a mathematical model and improve it with preprocessing techniques. Then, we propose a constructive heuristic and a variable neighborhood descent that are useful to solve large instances. Extensive computational experiments on benchmark instances prove the effectiveness of the algorithms.
@article{arxiv.2004.13396,
title = {Exact and heuristic solutions for the assembly line balancing problem with hierarchical worker assignment},
author = {Nicolas P. Campana and Manuel Iori and Mayron C. O. Moreira},
journal= {arXiv preprint arXiv:2004.13396},
year = {2020}
}