A Mathematical Model Integrating Line Balancing, Equipment Selection, and Workforce Management

Designing reconfigurable and adaptable assembly lines is crucial in today’s fast-paced manufacturing world. Due to the intense competition, manufacturing must keep pace with rapidly changing technology. However, this can lead to problems such as the premature end-of-life of equipment. This study explores the integration of second-hand equipment in the assembly line design problem to extend resource lifecycles and reduce costs. We propose a Mixed Integer Linear Programming (MILP) model for addressing the assembly line design problem, taking into account line design, equipment management, and workforce management problems aimed at minimizing the total cost of the line. We perform a numerical study to explore the implications of second-hand equipment on the cost of an assembly line. These experiments are based on a simulation where the line is reconfigured in each generation, where a generation corresponds to a modification of the product family. The results of this work indicate a dual effect. On the one hand second-hand equipment significantly reduces the cost of the line. On the other hand, the resulting line requires frequent technician training.