Prescribed convergence time control of spacecraft attitude dynamics with parametric uncertainty

The prescribed convergence time control issue of spacecraft with parametric uncertainty in inertia and disturbance is investigated. An adaptive sliding mode control solution is given. As a stepping stone, a new practical predefined-time stability theorem is established for a class of nonlinear systems. Its maximum convergence time is independent of initial states and explicitly prescribed via a gain given by the users. An adaptive predefined-time sliding-mode manifold is then developed. A chattering-free and nonsingular predefined-time controller is finally designed. The spacecraft attitude dynamics’ states are governed into a tiny neighborhood with arbitrary small radius after the prescribed time. The performance of this control solution is validated through two simulation examples.