Adaptive terminal sliding mode finite-time attitude control of spacecraft

An adaptive terminal sliding mode based finite-time control scheme is proposed for the attitude maneuver control of spacecraft, in which the parameters uncertainty and external disturbances are taken into account explicitly. In the proposed controller, a single parameter is adjusted dynamically in such a fashion that no information of uncertainty and/or disturbance is required in advance, and only the boundedness of these is assumed to allow the spacecraft to perform given operations. Lyapunov stability analysis shows that the resulting closed-loop system is proven to be stable and the effect of the external disturbances can be attenuated by appropriately choosing the design parameters. Numerical examples are also presented to demonstrate that the control algorithms developed are not only robust against uncertainty and external disturbances, but also able to achieve the control target in given finite time.