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Journals / Endüstri Mühendisliği / 2026 / Cilt: 37 Sayı: 2

A MULTI-OBJECTIVE OPTIMIZATION APPROACH FOR ERGONOMIC U-SHAPED MIXED-MODEL ASSEMBLY LINE BALANCING PROBLEM

ERGONOMİK U TİPİ KARMA MODELLİ MONTAJ HATTI DENGELEME PROBLEMİ İÇİN ÇOK AMAÇLI OPTİMİZASYON YAKLAŞIMI

Seçil Kulaç(BURSA TEKNİK ÜNİVERSİTESİ)0000-0003-3432-0099
Pages
435–466
Publication Date
2026-08-28
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

Computational results indicate an average reduction of 10.9% in cycle time for MOPSO relative to NSGA-II, particularly for medium- and large-scale instances.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:A multi-objective ergonomic U-shaped mixed-model assembly line balancing problem is formulated by integrating operational efficiency and human-centered performance within a unified optimization framework.
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Key Findings & Data:Computational results indicate an average reduction of 10.9% in cycle time for MOPSO relative to NSGA-II, particularly for medium- and large-scale instances.
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Conclusion & Impact:The results suggest that the proposed framework provides an effective and scalable approach for simultaneously addressing productivity and ergonomic performance in complex assembly systems.
🔬Design:Modeling & Simulation
📍Scope:Comprehensive Sample
⚙️Variables:Montaj hattı dengeleme · U tipi montaj hattı · Karma modelli üretim

Abstract

A multi-objective ergonomic U-shaped mixed-model assembly line balancing problem is formulated by integrating operational efficiency and human-centered performance within a unified optimization framework. The model simultaneously minimizes cycle time, maximum ergonomic risk, and ergonomic class imbalance, enabling the joint evaluation of workload intensity and its distribution across stations. Ergonomic risk is quantified using the energy expenditure (EE) method, providing a continuous and decision-dependent assessment of physical workload. Two Pareto-based metaheuristic algorithms, Non-dominated Sorting Genetic Algorithm II (NSGA-II) and Multi-objective Particle Swarm Optimization (MOPSO), are employed under a consistent solution representation and feasibility mechanism. Computational results indicate an average reduction of 10.9% in cycle time for MOPSO relative to NSGA-II, particularly for medium- and large-scale instances. In addition, MOPSO yields comparable ergonomic risk and class imbalance values, while producing a wider and more diverse Pareto front. Lower computational times are also observed, indicating improved solution efficiency. The results suggest that the proposed framework provides an effective and scalable approach for simultaneously addressing productivity and ergonomic performance in complex assembly systems.

Özet

Bu çalışma, operasyonel verimlilik ile insan odaklı performansı bütünleşik bir optimizasyon çerçevesi içerisinde entegre ederek, çok amaçlı ergonomik U tipi karma modelli montaj hattı dengeleme problemini ele almaktadır. Önerilen model, çevrim süresi, maksimum ergonomik risk ve ergonomik sınıf dengesizliğini eş zamanlı olarak minimize etmekte olup, iş yükü yoğunluğu ile bunun istasyonlar arasındaki dağılımının birlikte değerlendirilmesine olanak sağlamaktadır. Ergonomik risk, fiziksel iş yükünün sürekli ve karara bağlı bir değerlendirmesini sağlayan enerji harcaması (EE) yöntemi kullanılarak hesaplanmaktadır. Problemin çözümü için, Baskın Olmayan Sıralama Genetik Algoritması-II (NSGA-II) ve Çok amaçlı Parçacık Sürü Optimizasyonu (MOPSO) olmak üzere iki Pareto tabanlı meta-sezgisel algoritma, tutarlı bir çözüm temsili ve uygulanabilirlik mekanizması altında kullanılmaktadır. Hesaplama sonuçları, özellikle orta ve büyük ölçekli problemler için, MOPSO’nun NSGA-II’ye kıyasla çevrim süresinde ortalama %10,9 oranında azalma sağladığını göstermektedir. Ayrıca, MOPSO benzer düzeyde ergonomik risk ve sınıf dengesizliği değerleri üretirken, daha geniş ve daha çeşitli bir Pareto çözüm kümesi elde etmektedir. Daha düşük hesaplama süreleri gözlemlenmiş olup, bu durum çözüm verimliliğinin arttığını göstermektedir. Elde edilen bulgular, önerilen yaklaşımın karmaşık montaj sistemlerinde üretkenlik ile ergonomik performansın birlikte ele alınmasına yönelik etkili ve ölçeklenebilir bir yöntem sunduğunu göstermektedir.

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Cite This Article

Kulaç, S. (2026). A MULTI-OBJECTIVE OPTIMIZATION APPROACH FOR ERGONOMIC U-SHAPED MIXED-MODEL ASSEMBLY LINE BALANCING PROBLEM. Endüstri Mühendisliği, Cilt: 37 Sayı: 2, 435–466. https://doi.org/10.46465/endustrimuhendisligi.1944966

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