Robust Attitude Regulation of Uncertain Spacecraft with Flexible Appendages

This paper elaborates on robust attitude regulation design for flexible spacecraft with uncertain systematic parameters and external disturbances. We first establish an attitude deviation system based on several new coordinates, to formulate the robust attitude regulation problem in terms of input-tostate stability (ISS) (see [1]). Associated with an internal model approach, we achieve external harmonic disturbances rejection and arrive the so-called augmented system. Then, the augmented system allows us to carry out an input-to-state stabilizing design, leading to not only robustness property against systematic uncertainties but also actuator noise attenuation property. Finally, a numerical simulation example is given for illustration.