Scheduling of Automated Guided Vehicles in Automated Container Terminals

We study an automated container terminal in which Automated Guided Vehicles (AGVs) are used to internally transport containers and Automated Stacking Cranes (ASCs)to store and retrieve containers. A key issue in automated container terminals is the assignment of transportation orders to automated guided vehicles (AGVs). The aim of AGV scheduling is to dispatch a set of AGVs to improve the productivity of a system and reduce delay in a batch of pickup/drop-off jobs under certain constraints such as deadlines, priority, etc. In this paper a model to simulate AGV operations at a container terminal is proposed. In our model the terminal is assumed as a system that has to be designed and/or controlled in order to achieve the best performance on the basis of the existing resources. The model has been based on Petri Net. This approach turns out to be very convenient for achieving the desired tasks because the Petri's nets are based on the graphical representation by means of the net elements is easily perceived by man, i.e. there an easy way of visualization of the transport problem under consideration. A genetic dispatching algorithm that schedules the dispatch of AGVs is used to reduce the computation time and makes the dispatching algorithm capable of real time implementation.