A vectored water jet propulsion method for autonomous underwater vehicles

Abstract

Combination of propeller and rudder is most widely used by autonomous underwater vehicles (AUVs). But the cavitations and noise caused by the revolving blades along with the steering shortage of rudder in special working condition make it inadequate for AUVs which require high speed, high mobility and acoustic stealth performance. A water jet thrust vectoring method is put forward in this paper for AUV's propelling and heading and attitude control. Though this method, reaction thrust of water jet produced by volumetric water pump can be directionally controlled by a vectored nozzle. This approach has advantages of low cavitations, low noise and high mobility. The structure of an AUV equipped with a vectored thruster was presented. Additionally, a 3-DOF parallel manipulator is employed for thrust vector control which is driven by water hydraulic system, and the parallel manipulator is analyzed in kinematics and dynamics. With regard to defects in conventional PID control, an integral separation PID controller was designed for the parallel manipulator. Modeling and simulation of the parallel manipulator was conducted in Simulink and SimMechanics to verify the performance of the thrust vector control system. Finally, analysis of vectored thrust shows superiority and potential for steering of high speed AUVs.