Effect of ergonomic aspects on single- and multiproduct assembly-line balancing problems

Abstract

Incorporating ergonomic considerations into an assembly-line balancing problem (ALBP) enhances productivity and minimizes ergonomic concerns. The assembly process, characterized by repetitive motions and handling numerous components, can lead to worker overload. Consequently, the inclusion of ergonomic aspects results in an appropriate distribution of assembly operations and relative workloads. This study investigates a multi-objective ALBP aimed at minimizing the number of workstations, overall skill level required, and variance in workers' energy expenditure across workstations. To address the ALBP while considering the ergonomic aspects, this study proposes an approach based on the non-dominated sorting genetic algorithm II (NSGA-II) and multi-objective simulated annealing (MOSA) using Pareto optimality. A comparative analysis of the NSGA-II and MOSA is conducted in single- and multiproduct production scenarios, and a computational study involving various factors is performed to identify the dominant algorithm. The computational analysis indicates that the runtime performance of MOSA is 73.287% better than that of NSGA-II; therefore, MOSA outperforms NSGA-II. This study aims at applying scientific knowledge concerning manufacturing ergonomics to assist manufacturing industries in enhancing their productivity.