Research And Design Of Embeded Ship Collision Avoidance Monitoring System Based On AIS Information

With the number of ship increased greatly and the size of ship have been developing towards large capacity and high speed, the wrecks happen frequently, which threaten sailing security and ocean environment tremendously. Although Radar and ARPA have the ability of identify ships in the marine. The inherent disadvantages of the two equipments which lead to they can't provide automatic collision avoidance information, they can't satisfy the demand of modern shipping. The application of AIS system in recent years has brought about a thorough change to the approaches of getting information about meeting ships, resulting in the share of precise information among meeting ships. In a word, AIS brings about a revolutionary progress to ship monitor in the sea.The paper uses the data which provides by AIS as the information origination, a ship collision avoidance monitoring system based on AIS information is researched with embedded computer technology. First, the paper introduces the AIS sentence format and communication charaters which are defined by IEC61162. According to the protocol, the method how to decode AIS information is introduced. Second, the major knowledge of the ship collision process is analysed. It quantificationally plots out the ship encounter situation and collision avoidance actions for such situation, and discusses the range that the action should be taken.Then, a model which based on fuzzy mathematics theory and all kinds of influencing factor is established, with this model which divided the risk of collision into the risk factor of space collision and the risk factor of time collision. Finally, the embedded ship collision avoidance monitoring system based on AIS information is designed depended on the mathematic model.The system consists of monitoring system and information management of AIS; the paper chooses S3C44B0X chip, which has the features of low consumed power, low cost, high performance and small size based on ARM architecture; uses VxWorks as the operation system. The system affords of many functions such as displaying the ships in the domain of collision, inquiring about the information and the collision avoidance scheme of meeting ship, watching ships and waring report automatically. The major advantage of this system is convenient, real-time response, stronge expansion, and so on. The system also makes up the shortcomings of traditionary AIS syetem that the dark displaying information and low utilization ratio. It provides a suitable programme of action for ship collision avoidance. This system brings great advantage in field of navigation.