Adaptive control of uncertain non-affine pure feedback nonlinear systems using backstepping techniques

In this paper, a robust adaptive control law for a class of uncertain non-affine nonlinear systems is proposed. The proposed controller guarantees asymptotic output tracking of systems in the pure feedback form with unknown static parameters and non- affine controller. This controller takes advantages of a robust stability property of the Lyapunov redesign method and a systematic design procedure of the backstepping technique. Using the Lyapunov redesign method in each step of the conventional backstepping technique makes backstepping robust. The suggested controller is designed through repeatedly utilizing the Lyapunov redesign method in each step of the backstepping technique and derivative of the controller. Simulation results reveal the efficiency of the Lyapunov redesign-based backstepping controller.