ACTIVE DISTURBANCE REJECTION CONTROL FOR THE ATTITUDE STABILIZATION OF A SPACE TETHERED PLATFORM

In the tethered-assisted deployment or retrieval phases of the payload, an active disturbance rejection control method based on linear extended state observer is proposed for the attitude stabilization of a tethered platform which endures time-varying disturbance moment arising from the offset. The total disturbance is treated as an extended state which can be estimated by the observer. The control law is obtained by subtracting the extended state from an optimal control law designed on the assumption with no uncertainties. Simulation results show that the method not only estimates and compensates the disturbances, but also applicable to different kinds of disturbances. The controller meets the requirements of high stability.