Sliding mode control for a satellite attitude tracking system

The main problem addressed is the attitude tracking control of rigid satellite in the presence of inertia matrix uncertainty and external disturbances. A sliding mode controller with PID sliding surface is presented. A detail stability analysis of the close loop system is include, and while there exists uncertainty in satellite inertia parameters or external disturbance, this control scheme has global stability and robustness. Simulations are performed for the satellite attitude control system. Simulation results demonstrate that the control scheme realizes the attitude tracking control and is robust to parametric uncertainty and to external disturbance torques.