when the underwater high-speed supercavitation vehicles aft end pierces the bubble generated planning force,for the phenomenon of periodic collisions,the control mothod based on observer is used to compensate and eliminate the influence of gravity.Disturbance observer equation was deduced and the compensator was given.Simulations of vehicle maneuvers demonstrate that the compensation can avoid the phenomenon of cyclical collisions,and control surface deflection angle satisfy the requirements of the scope of...