Abstract：To solve the problems of complex environment, many obstacles and difficult practical application for underwater unmanned vehicle path planning, the A* algorithm path planning method was proposed based on geomagnetic matching aided navigation. Definitions of maneuvering performance constraints of sailing time constraints, maximum range constraints, turning angle constraints and obstacle collision constraints of vehicle were given. The search direction of the A* algorithm was optimized to reduce the needed searching number of nodes and improve the efficiency of path planning. The greedy method was used to search the removal of redundant nodes for reducing the turning number of the unmanned underwater vehicle. The geomagnetic information entropy was introduced into the fitness function, and the paths were planned according to the regions with geomagnetic information changed significantly and verified by the MAGCOM geomagnetic matching algorithm. The comparative simulation experiments including vehicle maneuverability constraints, background geomagnetic information, underwater topography and underwater threats were designed. The results show that by the improved A* algorithm, the path length is reduced by 42.02%, and the number of turns is decreased by 92.31%, while the path has good geomagnetic matching adaptability, which can effectively reduce the matching radial error and mean square error.
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