Scheduling unbalanced cellular manufacturing systems with lot splitting

Abstract

Recently, a large number of studies have addressed lot splitting as a means to reduce flow times as well as improve due date performance. Furthermore, a number of studies have examined scheduling policies in cellular manufacturing systems. These studies have been conducted under a variety of experimental factors, shop structures and operational assumptions. This study examines scheduling cellular manufacturing systems in the presence of lot splitting. In addition, we utilize various scheduling policies to test formally the underlying principles of the synchronous manufacturing philosophy. This is accomplished by utilizing exhaustive and non-exhaustive scheduling heuristics simultaneously at bottleneck and non-bottleneck workcentres. The results indicate that, under certain conditions, performing additional set-ups before the bottleneck can improve due date performance without an adverse effect on average flow time. Furthermore, we show that incurring additional set-ups after the bottleneck does not improve due date performance and may deteriorate flow time performance. These results conflict with some of the tenets of the synchronous manufacturing philosophy.