Application of metaheuristics to a mixed-model assembly line problem for minimizing makespan

In this paper, we applied a metaheuristic method to a mixed-model assembly line problem for minimizing makespan. In order to calculate the makespan including line stop time, the work progress of semi-finished products needs to be formulated. The formulations become difficult, so the conditions for the assembly line problem increase. Therefore, simulation - step-by-step time processing - is used to check the work progress in complicated mixed-model assembly line problems. However, many repetitive calculations are needed in simulation methods and the metaheuristic method we used required much computational time to solve a problem. Then, we presented the use of approximate expression instead of the formulations of work progress, and used the approximate expression in the first stage and simulation in the last stage.