On the integration of card-allocation and dispatching decisions in POLCA systems: an assessment by simulation

Abstract

POLCA is an important card-based control system for low volume, high variety production contexts. A job can only be produced at an upstream station if it has acquired a POLCA card that has returned from its downstream station. A common assumption in the POLCA literature is that cards are allocated to jobs as soon as they return to the upstream station. This dissects the queue in front of a station into jobs that have a card (and can be produced) and those that do not have a card (and cannot be produced). This artificially and prematurely constrains the dispatching decision, i.e. the decision concerning which job to produce next at a station. In response, this paper proposes integrating the card-allocation and dispatching decisions such that the allocation of POLCA cards to jobs is postponed until the dispatching decision is made. Simulation results demonstrate that this integrated approach does not improve performance under simple ERD dispatching, as is commonly applied in the POLCA literature. But when a more powerful rule is applied, percentage tardy and mean tardiness performance improve by more than 75% and 50%, respectively, for an integrated decision. Most importantly, results suggest that in production environments like the one considered in this study, the integrated approach dispenses with the use of POLCA altogether if a suitable priority rule is used.

Keywords:

• POLCA
• card-allocation decision
• dispatching decision
• discrete event simulation

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by Fundação para a Ciência e Tecnologia (UIDB/00319/2020) and National Natural Science Foundation of China (71872072).

Notes on contributors

Nuno O. Fernandes

Dr. Nuno O. Fernandes, PhD, is currently working as Professor of Operations Management at Polytechnic Institute of Castelo Branco (Portugal) and as Researcher at ALGORITMI (University of Minho, Portugal). He received is PhD in Production and Systems Engineering from the University of Minho. His research interests are in Production Planning and Control, Workload Control and Discrete Event Simulation. He has published and acted as reviewer in several international journals.

Matthias Thürer

Prof. Matthias Thürer is Distinguished Professor in Management Science and Engineering at Jinan University (Zhuhai, PR China). Before getting involved in academia, Matthias worked in several companies, did an apprenticeship and became a master craftsman (‘Meister’). He contributed to the improvement, simplification and integration of material flow control systems, and their integration with Industry 4.0. Apart from Operations Management, Matthias is also interested in social and philosophical issues including system theory, cybernetics, causality, and philosophy of science.

Mark Stevenson

Dr. Mark Stevenson is a Professor of Operations Management at Lancaster University Management School in the UK. He has published broadly on topics related to production planning and control in low-volume, high-variety production contexts, including on the concept of Workload Control. His work has appeared in a range of journals, including the Journal of Operations Management, Production and Operations Management, and the International Journal of Operations & Production Management as well as Production Planning & Control.