Sub-Optimal Control Law for Minimum Energy Attitude Maneuver using CMGs

Single Gimbal Control Moment Gyro (SGCMG) is an effective actuator for three axis attitude control of the satellites. Since satellite missions conduct with limited energy supplies in space, it is required to reduce the energy consumption during attitude maneuvers. However there are two problems with finding the optimal solutions for minimum energy maneuvers: the initial assumption and the calculation cost. To solve these problems, this study introduces a new sub-optimal control law to achieve the sub-minimum energy maneuvers without both initial assumption and iterative calculation. Compared to conventional steering law, the sub-optimal control law results in decreasing the energy consumption by more than 80 percent for all maneuver axis.