Autonomous underwater vehicle control based on adaptive backstepping method

An adaptive controller for the dive-plane of high-speed autonomous underwater vehicle(AUV) is designed.Most approaches of AUV's depth control are under an assumption that the pitch angle is near zero,which is not the case and may induce large modeling errors,and even may cause severe problems in some practical applications.Considering the unknown parameters and nonlinearities,an adaptive backstepping control law is derived for the depth control of AUV without any assumption on the pitch angle.In the closed-loop system,asymptotic stabilization of depth tracking is accomplished.Simulations illustrate the robustness of the proposed controller to model uncertainties,as well as its advantages over the traditional proportional-integral-differential(PID) controller with inner and outer loops.