Barrier Function-Based Adaptive Twisting Controller

A novel adaptive twisting controller strategy is designed for the case of second order disturbed systems whose disturbance is bounded with unknown boundary. This strategy consists in using a Barrier Function to adapt the control gain. This barrier strategy can ensure the convergence of the Lyapunov function, and maintain it in some predefined neighborhood of zero. This barrier strategy also has two main advantages: it does not require any information about the upper bound of disturbance, and does not overestimate the control gain.