Mixed-Model Assembly Lines Balancing Problem Based On Human Factors

In order to meet the individual needs of customers, more and more advanced manufacturing companies used mixed model assembly lines instead of the traditional simple assembly line. However, due to the production of multiple products at the same time, the assembly line will cause more costs and unnecessary waste if not been balanced. In the mixed model assembly lines balancing problem, operators are major components of the mixed model assembly lines that have an impact on balancing results. In this paper, some relevant factors that may affect the results of mixed model assembly line balancing from the operator are considered.This article obtains from the two types of balance goal that minimize the number of workstations or minimize the cycle time for analysis. In the mixed model assembly lines balancing problem of type I, psychological tolerance and physical exhaustion of every operator in the given cycle time were introduced and restrained to meet the psychological needs and physical demand. In the mixed model assembly lines balancing problem of type II, by incorporating workers' fatigue and recovery process, we attempt to smooth out the physical workload of the workers in order to improve the performance of the mixed-model assembly lines.Two kinds of models are given in this paper, and solved by genetic algorithms. The results were compared and showed that in the original mixed model assembly lines balancing problem give full consideration to the operator not only can distribute the work load of each workstation reasonably to meet the operator psychological needs and physical needs, but can ensure that each operator can have a good working condition.