Performance analysis of continuous non-smooth attitude control for spacecraft

For a class of continuous non-smooth attitude controllers for spacecraft, input-to-state stability theory of nonlinear systems is used to conduct performance analysis, and the conditions of attenuation against exogenous disturbances and robustness against uncertainties are given for the closed-loop systems. First, sufficient conditions for the input-to-state stability are given for a class of homogeneous systems. Then these conditions are applied to the performance analysis of the attitude control systems for spacecraft, and it is theoretically proven that good attenuation against external disturbances and robustness against bounded uncertainties are achieved for the closed-loop systems under the continuous non-smooth controllers. Numerical simulation and comparison are carried out to verify the theoretical analysis.