Abstract:According to its mission, underwater vehicle usually loading different combat payload, the lid opening process during vehicle rising is a key action flow of operation process. The underwater vehicle system will be affected by wave force, rocket thrust, gravity, fluid resistance and other factors during working process, and its lid opening process generates relative motion between the components, which makes its motion characteristics complex. The underwater vehicle system was studied in this paper. The dynamic equation of the system was established based on Kane method. The mixed coordinate method is selected to describe the motion of rigid body. The motion response of underwater vehicle under different load case was calculated and the factors affecting the lid opening process were analyzed.The results show that increasing the thrust force or the piston stroke of thruster can obviously shorten the time of lid opening process. The lid opening process has little effect on the motion of underwater vehicle. The higher the barycenter position of the lid, the shorter the time to reach the angular velocity inflection point, and the more favorable to lid opening process. When the initial inclination angle of the underwater vehicle is consistent with the rotation direction of the lid, the time of lid opening process can be shortened obviously. The inclination angle of the underwater vehicle has little influence on the effect of thruster.