Cyclic Assembly Schedules for Dynamic Demands

Abstract

Cyclic schedules, where fixed order interval lengths apply for all items, offer practical benefits in terms of ease of planning and control. Cyclic schedules are frequently preferred in practice, even though they result in higher total costs than non-cyclic schedules when demand is not constant. This study investigates the additional cost of cyclic scheduling in multistage assembly systems where demands vary from period to period, as in material requirements planning (MRP) environments. Capacity constraints are not included in the study.

A mathematical formulation of the cyclic problem is developed, and an algorithm to solve the problem is presented. Testing is then performed to compare the costs of optimal cyclic and non-cyclic schedules. Coefficient of demand variation is the key factor affecting the additional cost of cyclic schedules. Results show that additional costs are quite moderate under a wide range of conditions.

Additional information

Notes on contributors

Gerard M. Campbell

Gerard M. Campbell is Associate Professor of Operations and Information Management at the University of Connecticut. He received his Ph.D. from Indiana University in Bloomington with a double major in operations management and decision sciences. Dr Campbell also has an M.B.A. from the University of Connecticut and a B.S. in mechanical engineering from Columbia University. Currently his research interests include cyclic production scheduling, facility location, work force scheduling, and transportation-related applications of decision analysis. Dr Campbell has published in Management Science, Decision Sciences, Production and Operations Management, European Journal of Operational Research, Journal of the Operational Research Society, Transportation Research Record, and other refereed journals.