Cooperative Terrain Matching And Navigation For Dual Autonomous Underwater Vehicles

Underwater terrain matching navigation relies on bathymetric terrain information and prior map for matching positioning,which can correct inertial navigation error without floating to receive GPS.Compared with other navigation and positioning methods,it has great advantages,and can be used for long-range navigation and positioning of underwater AUV.Because the background of this paper is the long-range terrain matching navigation under the Arctic ice,we need to be fully aware of the large error of terrain matching navigation under the influence factors of the coarse resolution and flat terrain area of the International Bathymetric Chart of the Arctic Ocean Therefore,considering the above factors,this paper designs a dual AUV terrain matching cooperative navigation algorithm,through the cooperative positioning between the two AUVs,to meet the requirements of long-range navigation accuracy.Firstly,the seabed digital map elevation model with confidence information is analyzed and established,which realizes the effective use of information under the condition of inaccurate map data,solves the credibility problems caused by different sources of the International Bathymetric Chart of the Arctic Ocean,and lays the foundation for subsequent terrain matching navigation and path planning.Secondly,a dual AUV path planning method considering terrain matching navigation accuracy is designed to solve the path optimization problem under the constraints of terrain feature richness,terrain information confidence and communication distance.The global path planning of AUV1 is realized by improving the optimal cost function of A ~* algorithm,and on basis of this,AUV2 is planned again,the path planning of dual AUV considering the accuracy of terrain matching navigation and positioning is realized.Finally,a dual AUV terrain matching cooperative navigation algorithm is proposed,terrain matching navigation and positioning by particle filter,the distance based cooperative navigation algorithm is used to fuse the position of AUV,the credibility of terrain matching positioning results and the distance measurement information between AUVS in each communication cycle to correct the position of AUV.Compared with single AUV,the navigation and positioning accuracy is improved.Considering the problem of "particle degradation" and the mismatch of flat terrain area,the algorithm is improved,an improved dual AUV terrain matching cooperative navigation method based on terrain adaptation is proposed,which solves the problem of large positioning error caused by map resolution,flat terrain area and the size of matching area in the long range of single AUV terrain matching,and realizes the cooperative navigation and positioning of AUV.