Active disturbance rejection control of attitude for spacecraft

In order to attenuate the effects of the parameter variations and disturbances of the spacecrafts on attitude control accuracy and stability, an active disturbance rejection controller (ADRC) is designed. ADRC consists of three parts: tracking differentiator (TD), extended state observer (ESO) and attitude feedback controller (AFC). TD smoothes the process of attitude maneuver and provides differential signal of the attitude; ESO estimates the attitude and the disturbances acting on the spacecraft by taking full advantage of the information of the gyros and the attitude sensors; AFC realizes the attitude control of the spacecraft by compensating the disturbances from the ESO. Compared with the relative results, ESO has better performance by adopting the composite measurement information to correct the estimate, and ADRC has simpler structure by adopting only one loop to realize attitude control and disturbance compensation. Simulation results of a certain spacecraft demonstrate that the ADRC of this paper is feasible.