Attitude Maneuver and Gimbal angle guidance by SDRE controller using SGCMG integrated satellite SDLR model

In the conventional agile attitude maneuver of a satellite, a control system of the satellite and Single Gimbal Control Moment Gyro (SGCMG) is designed separately and stability is not guaranteed under the singularity of SGCMGs. Therefore, in this research, we integrate the satellite and SGCMGs and design a model with the gimbal angular velocity as input. Since the target gimbal angle can be explicitly designed by a null motion, proposed control system is possible to guide the initial gimbal angle which is advantageous for next mission. In addition, it is shown that proposed method can guarantee stability even under the singularity of SGCMGs by the State-Dependent Riccati Equation (SDRE). Moreover, numerical simulations show that the singularity avoidance performance up to the target gimbal angle and the guidance performance of the gimbal angle are higher than the conventional method due to the optimality of gimbal angular velocity input.