Robust attitude controller design of linear parameter varying spacecraft via μ synthesis and gain scheduling

Studies the three-axis attitude control problem of a spacecraft which has slowly rotating flexible solar paddles. By the paddle rotation, the structure of dynamical coupling of the paddle vibration with the spacecraft attitude dynamics drastically changes. In order to control such a class of spacecraft, we derive a parameter-varying modal equation and a generalized plant of descriptor form. Then, two stabilizing controllers, i.e., a fixed μ controller and a gain scheduled H_∞ controller are designed. Based on some numerical studies for the ETS-VI spacecraft model, their capabilities are shown and compared with each other