Research Of Intercommunication Method Of Multi-AUV Cooperation

Autonomous underwater vehicle system is an important tool which will be applied in ocean exploration, development and a variety of underwater intelligent tasks. As an important development direction, the multi-AUV cooperation technology has become a present research focus. Each AUV assume its own responsibility in cooperation. The research of multi-AUV system positioning technology for underwater vehicle is an essential part of cooperation.Communication between water surface vehicles and underwater vehicles and intercommuncation between underwater vehicles are proposed to identify the positions of underwater vehicles. This paper discusses the basic principles of positioning technology for underwater vehicls, the architechture of multi-AUV and the position processes in different situations. After that, the reliablity of this position technology is proved.Firstly, the fixed and motion coordinate system, and the basic mathematic models of mutual positioning are established; based on the characteristics of the environment of the ocean, the current models in horizontal plane and vertical plane are established.Secondly, the basic architecture of multi-AUV is introduced, and the role of each AUV in a multi-AUV system is identified; the clock synchronization principle and necessity of multi-AUV system are introduced; both of the communication rules and comunication process are also introduced.Thirdly, when the surface vehicle is static, underwater vehicles's positions are given by multi-AUV system in two voyage status: unchanged depth status and changed depth status. A method to inspect the positioning result is given by analysing the position errors in cases, and the advatanges and disadvantages of positioning performance when surface vehicles and underwater vehicles have different positional relations are discussed.Finally, when surface vehicles move, the positioning processes of multi-AUV system are studied. There are three different situations for positioning: underwater vehicles voyage in an unchanged speed, underwater vehicles voyage in a changed speed, and the current disturbances exist.