| Due to the booming in world trade, port authorities are looking into ways of making existing facilities more efficient especially in places where expansion of the terminals is not possible due to the scarcity of land. One way to improve efficiency, increase capacity and meet future demand is to use advanced technologies and automation in order to speed up terminal operations. The Automated Guided Vehicle System (AGVS) used intensively in manufacturing systems that handles and transports items from one location to another efficiently, is considered as one of the candidates for improving the efficiency of container terminal operations. The debut of AGVS successfully implemented in the Port of Rotterdam shows the efficiency of the system, and hence makes the AGVS promising for replacing the manual operations in the container terminals. However, before constructing the automated terminal and the deployment of AGVS, a computer simulation model is necessary to find the suitable terminal configuration for meeting the projected demand, and to investigate the potential problems before the successful implementation of the system. Petri Net is a well-known modeling tool that has the advantages of graphic nature, the conciseness of embodying both the static structure and the dynamics, and the availability of the mathematical analysis techniques. It is suitable for the application of modeling the Automated Container Terminal Systems (ACTS). Usually, in the manufacturing systems with AGVs as mean of transportation of job parts, it's hard to determine the optimal fleet size of AGVs for achieving a desired performance. Here, a heuristic approach, based on the ideal pipeline concept and Petri Net theory, is constructed to balance the dispatching and scheduling of the AGVs to minimize the number of AGVs for achieving the zero idle time of the machines (quay cranes). |
