Robot yer seçimi ve iþçi-istasyon atamasý düþünceleri altýnda hat dengeleme optimizasyonu: Bir bulaþýk makinesi fabrikasý vaka analizi

Bu makale bir Bulaþýk Makinesi Fabrikasýnda bulunan montaj hattý üzerinde yapýlmasý planlanan hat dengeleme çalýþmasý üzerinedir. Ana motivasyon, üzerinde çalýþma yapýlan montaj hattýný benzer iþleri gruplayarak daha dengeli hale getirmek ve vardiya baþýna üretilen bulaþýk makinesi sayýsýný arttýrmaktýr. Bu temel amaçlarýn yanýnda çalýþma; iþçi atamasýnýn yeniden yapýlmasný, iþ-stok alaný optimizasyonu ve istasyonlardaki iþ gücünün dengelenmesini hedeflemektedir. Ýstasyonlarýn, asansörün ve robotlarýn yer seçimi ile istasyonlara iþ ve iþçi atama kararlarýný dikkate alan yeni bir tam sayýlý programlama modeli öneriyoruz ve problemi kesin olarak çözmek için ticari bir çözücü kullanýyoruz. Problemin çözümünden elde edilen çýktýlar ýþýðýnda mevcut sistem ve iyileþtirilmiþ sistem sonuçlarý karþýlaþtýrýlmýþtýr. Öncelikle bulaþýk makinesi üretim kapasitesinin mevcut duruma göre artýþ deðerlendirmesi yapýlmýþ, ardýndan gruplanan iþlerin çevrim süresine olan etkisi deðerlendirilmiþtir. Yapýlan duyarlýlýk analizleri sonuçlarýna göre mevcut tempoyu, çevrim süresini ve iþçi sayýsýný iyileþtiren farklý sonuçlar önerilmiþtir. Bu sonuçlara göre, problemin diðer parametreleri sabitken, iþçi sayýsý %36 oranýnda azaltýlabilirken, vardiya baþý üretilen bulaþýk makinesi sayýsýný %52’ye kadar arttýrýlabilir. Bu çalýþmada firmaya önerilen sonuçta ise benzer iþler gruplanarak açýlan istasyon sayýsý 68% oranýnda azaltýlmýþ, istasyonlar tarafýndan kullanýlabilecek alan sayýsý mevcut sistem ile ayný tutularak iþçi sayýsý 10% oranýnda azaltýlmýþ ve çevrim süresinden 4,34 saniye kazanýlmýþtýr ve böylece vardiya baþý üretilen makine sayýsý %43 arttýrýlmýþtýr.

Line balancing optimization under robot location and worker-station assignment considerations: A case study of a dishwasher factory

The focus of this article is on the line balancing work planned on the assembly line of a Dishwasher Factory. The main motivation is to make the assembly line more stable by grouping similar jobs and to increase the number of dishwashers produced per shift. In addition to these basic objectives, this study aims to rearrange the number of operators, optimize work-stock area and balance the man power at the stations. We propose a novel integer programming model that takes into account the location selection of stations, elevators and robots and the decisions of assigning jobs and workers to stations and use a commercial solver to solve the problem exactly. In the light of the outputs obtained from the solution of the problem, the current system and the improved system results were compared. First, the increase of dishwasher production capacity under current operational guidelines was evaluated and then the effect of grouping jobs on cycle time was evaluated. Based on the results of the sensitivity analysis, different results were proposed to optimize the current tempo, cycle time and number of workers. The results indicate that the number of workers can be reduced by 36%, while the number of dishwashers produced per shift can be increased by up to 52%, when all other inputs of the problem are fixed. Compared to the current practice, in the solution proposed to the manufacturing firm, the number of stations opened with similar jobs grouped was reduced by 68%, the number of fields that could be used by the stations was kept the same, the number of workers was reduced by 10% and the cycle time was improved by 4.34 seconds and the number of machines produced per shift increased by 43%.