Design of feedback control system using nominal inputs for satellite attitude maneuver using Control Moment Gyros

Satellites orbiting the earth require large-angle and rapid rotational maneuverability. For this purpose Control Moment Gyros (CMG) needs to be applied to an attitude control actuator of a small agile satellite, because CMG can generate high torque effectively. CMG has a singularity problem which affects energy consumption and rapid actuation of CMG. In order to settle these problems we proposed feed-forward control logic using energy optimal path planning by Fourier Basis Algorithm (FBA). However, this logic does not hold robustness with several errors and disturbances. Therefore, this paper designs a feedback control system so as to obtain robustness with errors of initial CMG gimbal angles generated by natural environmental disturbances. The designed system is characterized by using the system's limit state, which is a new defined variable and is predicted by numerical integrals using nominal control inputs. The results of the several numerical simulations show the availability of the proposed logic about robustness with these errors, energy consumption, and safe use of CMG.