Simple heuristics for the assembly line worker assignment and balancing problem

TL;DR

This paper introduces simple, fast heuristics for the assembly line worker assignment and balancing problem, accounting for variable task times based on worker assignment, and demonstrates their effectiveness in various applications.

Contribution

The paper develops a set of simple heuristics tailored for the assembly line worker assignment problem with variable task times, and evaluates their performance in multiple contexts.

Findings

Heuristics are computationally efficient.

Heuristics produce good solutions as standalone methods.

Heuristics enhance meta-heuristics when used as initial solutions.

Abstract

We propose simple heuristics for the assembly line worker assignment and balancing problem. This problem typically occurs in assembly lines in sheltered work centers for the disabled. Different from the classical simple assembly line balancing problem, the task execution times vary according to the assigned worker. We develop a constructive heuristic framework based on task and worker priority rules defining the order in which the tasks and workers should be assigned to the workstations. We present a number of such rules and compare their performance across three possible uses: as a stand-alone method, as an initial solution generator for meta-heuristics, and as a decoder for a hybrid genetic algorithm. Our results show that the heuristics are fast, they obtain good results as a stand-alone method and are efficient when used as a initial solution generator or as a solution decoder within more elaborate approaches.