Fault-Tolerant Attitude Control System for a Spacecraft with Control Moment Gyros Using Multi-Objective Optimization

Recent years have seen a growing requirement for accurate and agile attitude control of spacecraft. To both quickly and accurately control the attitude of a spacecraft, Control Moment Gyros (CMGs) which can generate much higher torque than conventional spacecraft actuators are used as actuators of the spacecraft. The drive on the motors is needed for rapid maneuverability, negatively affecting their life. Thus, in designing spacecraft the conflicting requirements are rapid maneuverability and reduced the drive on motors. Furthermore, the attitude control system needs to be fault-tolerant. The dominant requirement is different for each spacecraft mission, and therefore the relationship between the requirements should be shown. In this study, a design method is proposed for the attitude control system, using multi objective optimization of the skew angle and parameters of the control system. Pareto solutions that can show the relationship between the requirements are obtained by optimizing the parameters. Through numerical analysis, the effect with fault-tolerance and parameter differences for the dominant requirement are confirmed and the method to guide for determining parameters of the attitude control system is established.