Attitude Control of Five-axis flexible Satellite Based on Active-disturbance-rejection Sliding Mode Method

By using Kane method, a mathematical model with Control moment gyroscopes as actuators was built for the five-axis satellite with flexible appendages. An active-disturbance-rejection sliding mode controller was designed for the demand about quickness and stability in attitude control. This controller contained the active-disturbance-rejection method and sliding mode method. It observed the disturbance by expanded state observer, and compensated the output. The slide mode method in the controller made the system quick and stable. The simulation experiments showed that the controller could control the attitude of the five-axis satellite efficiently and weaken the vibration of flexible solar panel. In the comparison with PID controller and general sliding mode controller, the active-disturbance-rejection sliding mode controller showed the merits of both active-disturbance-rejection method and sliding mode method. It is better in quickness than the other controllers. Thus, this controller would be valuable to be applied in the attitude control of satellites.