Simulation-based Assembly Line Balancing in U-shaped, Parallel U-shaped, and Parallel Adjacent U-shaped Layouts

This research focuses on simulation-based assembly line balancing by investigating three configurations in U-shaped assembly lines. The names of the three layouts are U-shaped lines, parallel U-shaped lines (PUL), and parallel adjacent U-shaped lines (PAUL). Since PUL and PAUL were proposed with limited implementations, this study adopts secondary data from a real case industry and models the selected layouts using ARENA simulation. Simulation results are utilized to compare the performances of the three layouts in terms of the number of workstations, line efficiency, and workload smoothness. Some tradeoffs are observed and discussed for the layouts and the selected KPIs. The results show that PAUL outperforms the U-shaped and PUL, but its average waiting time increases due to the least number of operators. Also, the total outputs lower as the cycle time increases. PAUL is a promising layout for improvement and implementation.