Aiming at the complex situations of uneven terrain, harsh operating environment and serious slippage of the vehicle in the deep-sea cobalt crust, a driven wheel speed measuring mechanism with terrain perception ability is designed and studied, and the trajectory estimation model of mining vehicles operating on non-flat terrain is established by using the method of composite three-dimensional terrain with different slopes at different times. Inclination sensor, electronic compass, angular displacement sensor, photoelectric encoder, etc. are used to measure the dynamic parameters of mining vehicles, and the underwater positioning of mining vehicles is realized according to the trajectory estimation model. Compared with the traditional track estimation method based on the speed of the driving wheel, it can adapt to various complex working conditions and ensure high positioning accuracy. The experimental results prove the effectiveness of the above method.