Route choice control for DCVs in baggage handling systems - Comparison between centralized and decentralized approaches

Reference:
A. Tarau, B. De Schutter, and H. Hellendoorn, "Route choice control for DCVs in baggage handling systems - Comparison between centralized and decentralized approaches," Proceedings of the 10th TRAIL Congress 2008 - TRAIL in Perspective - CD-ROM, Rotterdam, The Netherlands, 14 pp., Oct. 2008.

Abstract:
The process of handling baggage in an airport is time-critical. Currently, the fastest way to transport the luggage is to use destination coded vehicles (DCVs). These vehicles transport the bags at high speed on a "mini" railway network, but their route has to be controlled in order to ensure the system optimum. In this paper we determine an event-based model of a DCV-based baggage handling system and we compare centralized and decentralized approaches for routing the DCVs through the network. The proposed centralized control methods are optimal control and model predictive control (MPC). Due to the large computation effort required, we also analyze a fully decentralized control approach. In this case, each junction has its own local controller for positioning the switch into the junction or out of it, routing the DCVs through the network. The local controllers do not communicate their actions. The considered control methods are compared for several scenarios. Results indicate that optimal control becomes intractable when a large stream of bags has to be handled, while MPC can still be used to suboptimally solve the problem. However, the decentralized control method usually gives worse results to the ones obtained when using MPC, but with very low computation time.