Balancing Assembly Line with Moving Workers and Worker-Dependent Task Times Using Linear Programming Formulation

Murat Sahin; İsmet Soylemez

doi:10.17798/bitlisfen.1785785

Balancing Assembly Line with Moving Workers and Worker-Dependent Task Times Using Linear Programming Formulation

Abstract

This study addresses the moving heterogeneous worker assembly line balancing problem, a new variant of the classical problem that simultaneously considers worker-dependent task times and worker mobility between stations. In this setting, the processing time of each task differs according to the skills and efficiency of the assigned worker, while workers are allowed to move within a limited range to perform tasks at different stations. These features make the problem more realistic but also substantially more complex, as precedence relations, heterogeneous workloads, cycle time restrictions, and worker movements must all be satisfied simultaneously. To capture these interrelated aspects, mixed integer linear programming is proposed, which can provide exact solutions for small-sized instances. A dataset based on well-known precedence diagrams is generated to evaluate model performance across varying levels of task time variability and worker–station configurations. The results show that the formulation optimally solves small-sized instances, whereas medium and large instances remain computationally demanding, with increasing gaps and longer solving times. The findings further reveal that adding an extra workstation can improve efficiency, especially in larger-sized problem instances. Overall, this study contributes to assembly line literature with a novel mathematical model that integrates worker heterogeneity and mobility, highlighting future research opportunities for heuristic and metaheuristic approaches.

Keywords

Ethical Statement

There is no conflict of interest between the authors. The study is complied with research and publication ethics.

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Details

Primary Language

English

Subjects

Industrial Engineering

Journal Section

Research Article

Authors

Murat Sahin
0000-0003-3173-1749
Türkiye

İsmet Soylemez ^*
0000-0002-8253-9389
Türkiye

Publication Date

March 24, 2026

Submission Date

September 17, 2025

Acceptance Date

November 25, 2025

Published in Issue

Year 2026 Volume: 15 Number: 1

DOI

https://doi.org/10.17798/bitlisfen.1785785

IZ

https://izlik.org/JA85HL53PD

Cite

RIS / Bibtex

APA

Sahin, M., & Soylemez, İ. (2026). Balancing Assembly Line with Moving Workers and Worker-Dependent Task Times Using Linear Programming Formulation. Bitlis Eren Üniversitesi Fen Bilimleri Dergisi, 15(1), 177-187. https://doi.org/10.17798/bitlisfen.1785785

AMA

1.Sahin M, Soylemez İ. Balancing Assembly Line with Moving Workers and Worker-Dependent Task Times Using Linear Programming Formulation. Bitlis Eren Üniversitesi Fen Bilimleri Dergisi. 2026;15(1):177-187. doi:10.17798/bitlisfen.1785785

Chicago

Sahin, Murat, and İsmet Soylemez. 2026. “Balancing Assembly Line With Moving Workers and Worker-Dependent Task Times Using Linear Programming Formulation”. Bitlis Eren Üniversitesi Fen Bilimleri Dergisi 15 (1): 177-87. https://doi.org/10.17798/bitlisfen.1785785.

EndNote

Sahin M, Soylemez İ (March 1, 2026) Balancing Assembly Line with Moving Workers and Worker-Dependent Task Times Using Linear Programming Formulation. Bitlis Eren Üniversitesi Fen Bilimleri Dergisi 15 1 177–187.

IEEE

[1]M. Sahin and İ. Soylemez, “Balancing Assembly Line with Moving Workers and Worker-Dependent Task Times Using Linear Programming Formulation”, Bitlis Eren Üniversitesi Fen Bilimleri Dergisi, vol. 15, no. 1, pp. 177–187, Mar. 2026, doi: 10.17798/bitlisfen.1785785.

ISNAD

Sahin, Murat - Soylemez, İsmet. “Balancing Assembly Line With Moving Workers and Worker-Dependent Task Times Using Linear Programming Formulation”. Bitlis Eren Üniversitesi Fen Bilimleri Dergisi 15/1 (March 1, 2026): 177-187. https://doi.org/10.17798/bitlisfen.1785785.

JAMA

1.Sahin M, Soylemez İ. Balancing Assembly Line with Moving Workers and Worker-Dependent Task Times Using Linear Programming Formulation. Bitlis Eren Üniversitesi Fen Bilimleri Dergisi. 2026;15:177–187.

MLA

Sahin, Murat, and İsmet Soylemez. “Balancing Assembly Line With Moving Workers and Worker-Dependent Task Times Using Linear Programming Formulation”. Bitlis Eren Üniversitesi Fen Bilimleri Dergisi, vol. 15, no. 1, Mar. 2026, pp. 177-8, doi:10.17798/bitlisfen.1785785.

Vancouver

1.Murat Sahin, İsmet Soylemez. Balancing Assembly Line with Moving Workers and Worker-Dependent Task Times Using Linear Programming Formulation. Bitlis Eren Üniversitesi Fen Bilimleri Dergisi. 2026 Mar. 1;15(1):177-8. doi:10.17798/bitlisfen.1785785