Mixed-model Assembly Line Problem with Consideration of Sequence and Conveyor Speed Simultaneously under a Condition without a Line Stop

Abstract

The mixed assembly line problem is a problem to decide a job sequence. In order to determine the job sequence, it is assumed that the works are assigned to work stations. Usually, the cycle time is obtained from the operating time and the production volume during the planning period, and the works are assigned by line balancing. Therefore, many studies use a fixed time cycle when deciding the job sequence. This paper discusses an assembly line system that is able to adjust the conveyor speed in order to change the cycle time. Both the job sequence and the conveyor speed are determined. The authors aim to minimize the makespan under the condition that the line does not stop. To address this problem, the authors describe how to set the upper and lower limits of the optimal conveyor speed and the effect of the conveyor speed on the makespan. SA is applied to this problem and its effect is shown through numerical experiments.