Abstract
Footwear manufacturing is a traditional labor intensive industry, and plays an important role in the economy growth in Taiwan. The manufacturing process of shoes is generally separated into upper process and sole process, and stitching, which requires the most operators, is one of the most critical processes in upper process. This study uses Grouping Genetic Algorithm (GGA) to solve type III Resource-Constrained Assembly Line and Worker Assignment Balancing Problem (RCALWABP) in stitching lines of footwear manufacturing. With balancing of stitching lines, it can let workload of lines more smoothness, reduce operator requirement and increase production efficiency. This study takes into accounts several practical characteristics in footwear manufacturing, including multi-skilled operators, operator efficiency, task time variance and number of operators. Type III RCALWABP in stitching lines is solved using GGA to maximize workload smoothness and allocate the workload evenly with a given number of workstations. Real data from footwear factories is collected and used to evaluate the performance of GGA based on experimental design. The optimal parameters setting of GGA and production system are also obtained. Furthermore, this study takes budget as one the constraint, and uses it to verify the effect to objective value. This study can provide some idea for footwear factory to assign tasks to workstations and the efficiency can be improved.