A Multi-Worker Assembly Line Rebalancing with Spatial and Ergonomic Considerations

TL;DR

This paper introduces a multi-objective optimization model for rebalancing assembly lines with multiple workers, considering spatial and ergonomic constraints to improve feasibility and worker well-being.

Contribution

It presents a novel model that integrates task reassignment, ergonomic evaluation, and spatial constraints for multi-worker assembly line rebalancing.

Findings

Model generates feasible, human-centered reconfigurations

Consistently performs well across different cycle times

Enhances decision support for flexible production environments

Abstract

This work addresses the Assembly Line Rebalancing Problem in manual assembly systems where multiple workers operate in parallel within the same station - an industrially relevant scenario that remains insufficiently explored in the literature. A multi-objective optimization model is proposed that incorporates task reassignment, worker allocation, ergonomic evaluation, and explicit spatial feasibility through work-area constraints. The formulation minimizes deviations from the current configuration while promoting balanced workload and ergonomic conditions among workers. Computational experiments on synthetic problem instances demonstrate that the model consistently generates feasible and human-centered reconfigurations across varying cycle-time conditions, highlighting its potential as a decision-support tool for industrial rebalancing in flexible production environments.