Including Assembly Relationship Complexity into Assembly Line Balancing Problem

Traditional objectives of the assembly line balancing problem are cost and efficiency, without considering the assembly relationship complexity. However, the assembly relationship complexity of products has the effect on the quality of final products. A good planning decision for an assembly line can be made by taking the assembly relationship complexity into the assembly line balancing problem. Hence, in this paper, the assembly relationship complexity is considered and defined in the assembly line balancing problem. The assembly line workload smoothness and the assembly relationship complexity are considered simultaneously to improve workload balance and decrease assembly complexity. The measuring method for the assembly relationship complexity is developed. The objectives are minimizing the smoothness index and the assembly relationship complexity. An improved genetic algorithm is designed to deal with this problem. In the algorithm, the crossover procedure is modified by the Bagging ensemble clustering method to prevent imbreeding among chromosomes and increase the diversity of the population. The method proposed in this paper is verified by a real world case.