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Adaptive Second-order Sliding Mode Station-keeping Control for Solar Sail Spacecraft on Displaced Orbit

This paper proposes an adaptive second-order sliding mode control scheme for the station-keeping motion of the solar sail spacecraft on heliocentric displaced orbit, in the presence of uncertain parameters and external disturbances. Firstly, the nonaffine nonlinear dynamic model of the spacecraft using solar radiation pressure based on the circular restricted three-body problem (CRTBP) is derived. Secondly, in order to avoid the constraints of valid range caused by locally linearization method, a second-order sliding mode control law along with adaptive estimation is designed. Since the first and second derivatives of the sailcraft’s position are used in the control law, a high-gain observer is further constructed, utilizing only position measurement. Finally, numerical simulation verifies that the above design enhances the robustness of the system, and improves the control accuracy by 2 orders of magnitude in shorter convergence time compared to linearization method.