Nonsingular Terminal Sliding Mode Attitude Tracking Control for Rigid Spacecraft with Input Saturation

Abstract

A nonsingular terminal sliding mode (NTSM) control is used to address attitude tracking problem of rigid spacecraft with disturbances and input saturation. First, a NTSM surface is introduced, which eliminates the nonsingularity problem of the general control with sliding mode. Next, the NTSM control for tracking of spacecraft is investigated. In finite time the states shows that it can arrive at the mentioned surface rapidly, and a small region of equilibrium can be converged by the attitude tracking errors, and then approach to zero asymptotically. At the same time, the effect of input saturation has been considered in this research, and the proposed scheme can realize the fast finite-time attitude tracking with a small amount of control, which greatly reduces the input energy consumption in the actual system. Finally, the effectuality of the presented scheme is performed by the simulation results.