Analyzing the use of rework stations for parallel tasks in assembly line balancing via mathematical programming and simulation

Abstract

In assembly lines, rework stations are generally used for reprocessing defective items. On the other hand, using rework stations for this purpose only might cause inefficient usage of the resources in this station especially if the defective rate of the assembly line is low. In this study, first, a mixed-integer programming model for cycle time minimization is presented by considering the use of rework stations for parallel tasks. By linearizing the non-linear constraint about parallel tasks using a variate transformation, the model is transformed to a linear-mixed-integer form. Secondly, a novel simulation model is developed in the study for validating the results obtained using the integer programming model by incorporating stochastic problem components. Using the developed model, two sample problems are simulated and the applicability of the integer programming models results are analyzed.