Multi-beam underwater terrain matching method based on improved genetic algorithm

Under the condition of large initial position error, the traditional terrain matching algorithm has low positioning precision and is prone to false matching due to the large search area. To solve the problem, a multi-beam underwater terrain matching method based on improved genetic algorithm is proposed. Firstly, according to the characteristics of terrain changes, multiple water depth data are adaptively selected from multibeam bathymetric data as the matching sequence to improve the matching precision in similar terrain; Then, a fitness function is designed to measure the similarity between the matched track and the real track, and a convergence factor is added to reduce the influence of the accumulated error of the inertial navigation; Finally, the sine cosine algorithm is used to optimize the genetic algorithm to improve the convergence speed and the performance of local convergence. Simulation and shipborne experiments show that the multi-beam matching method based on improved GA is insensitive to the initial position error, and the matching positioning error is less than 3m on the topographic map with a resolution of 1 m. Compared with the ICCP method, the positioning accuracy of the proposed method is improved by 53% and 79% respectively under different initial position errors. © 2022, Editorial Department of Journal of Chinese Inertial Technology. All right reserved.