Simulation study on sea traffic control at an intersection utilizing information sharing with automatic identification system (AIS)

Sea traffic is confined within a 2D sea surface. Although there inevitably exists an intersection, boundaries of the intersection are vague as a result of free sailing of vessels on the sea surface. The Global Positioning System (GPS) and the Automatic Identification System (AIS) are now in service and they enable mutual communication among vessels in passage about their positions and speeds with their identities. The AIS can also provide various binary messages for traffic control by the Vessel Traffic Service Center (VTS). The VTS, therefore, can provide effective information to vessels in passage to avoid collision danger and for the smooth and efficient sea transportation. The conventional VTS gathered sea traffic information with Radio Detecting and Ranging (RADAR) systems and voice communication through Very High Frequency (VHF). The AIS provides precise information about vessels within the objective sea area of the VTS. It is possible for the VTS to indicate much safer courses and speeds to vessels in passage based upon the precise information with the AIS. We have developed a sea traffic simulation system (SEATRAS) for maritime safety assessment and development/improvement on navigation support systems and aids to navigation. As the SEATRAS has already supported the AIS communications, it is ready to be used for the VTS simulation for checking algorithm of a sea traffic control. On the SEATRAS we define an intersection zone and four neighboring zones. The VTS agent is also joined to the SEATRAS to gather status information of vessels in these zones with the AIS. The VTS makes an optimal set of navigation plans and gives orders or recommendations for the optimal plans to the respective vessels. We perform a simulation study using the SEATRAS and investigate on the safety and the efficiency of the sea traffic around an intersection..