Adaptive backstepping motion control of underwater vehicle with vertical thrusters

The nonlinear vertical motion control problem of a class of low-speed underwater vehicles equipped with vertical thrusters was studied. With consideration of the unknown parameters in dynamic model, a nonlinear adaptive controller was designed with backstepping technique to globally asymptotically stabilize the depth and pitch angle to their desired values. In the simulation studies, the proposed controller was applied to the REMUS underwater vehicle, and the results demonstrate the global asymptotical stability of the tracking errors and the adaptability to the previously unknown model parameters.