A comparison of scheduling philosophies for cellular manufacturing

Abstract

This thesis compares three approaches for assigning workers and scheduling the flow of jobs in a Group Technology (GT) cell. The performance measure considered is the throughput time of jobs. The performance of the three strategies is analyzed by varying the following factors: (1) The ratio of Batch processing time to setup time. (2) Utilization. (3) The number of operators assigned to the cell. The scheduling strategies considered are Individual Machine Loading, Cell Dedication and Worker Batch Assignment. Analytical queueing models as well as computer simulations are used to compare the performance of the scheduling strategies. The dedicated cells perform best with large batch sizes and moderate workloads. The Worker Batch Assignment strategy does as well as traditional batch handling techniques with respect to the throughput time measure. This may be important since this kind of job assignment strategy has the advantage of augmenting quality (due to direct accountability) and enhancing morale without adversely impacting throughput times.