Underwater Cooperative Target Localization Method Based on Double Orthogonal Moving Autonomous Underwater Vehicles

Autonomous Underwater Vehicle (AUV) localization is one of the main methods to locate underwater targets in large areas. Considering the defects of single AUV positioning, such as long positioning period, low positioning coverage area and large accumulation of positioning errors for a long time, a cooperative target localization method based on double orthogonal moving AUVs is proposed. Each AUV locates itself through its own Inertial Navigation System (INS) and Doppler log. Localization process is achieved through the measurement of time difference of arrive between the target and AUV in the course of multiple movements. This method requires two orthogonal moving AUVs with a relative heading angle of 90 degrees to achieve one positioning process by communicating at least two times. Compared with the traditional single mobile sensor positioning method, the proposed method requires shorter positioning period and lower synchronization requirements. Experimental results show that the positioning accuracy of this method is significantly improved, while the effective positioning area is enlarged, and the influence on AUV position error is lower in the long time positioning process.