Adaptive fast terminal sliding mode control for a class of uncertain systems with input nonlinearity

This study investigates the terminal sliding mode (TSM) control for a class of first-order uncertain systems with dead-zone and saturation. First, a new adaptive TSM control law was proposed for the single-input and single-output (SISO) systems by employing an integral fast TSM. It achieves rejection for both system uncertainty and input nonlinearity. The global reaching condition of the sliding mode is guaranteed by the Lyapunov stability theory. The new control law possesses faster convergence than the linear sliding mode method, and the singularity problem of TSM is avoided. Then, the control law was extended for tracking control of a dynamic model of spacecraft which was a multi-input and multi-output (MIMO) system. Finally, the simulation results confirmed the effectiveness of the proposed control method.