Abstract: In the large radio telescope (LRT) engineering, the six large span cables are employed to tune the feed supporting system to implement the big workspace trajectory tracking of the position and attitude. Considering the special characteristics of inertia mainly concentrating on the cabin, slow velocity of cabin system and the strong coupling among cables, a dynamical model for the cabin is built based on Newton-Euler method and the nonlinear stationary equilibrium equations of the cable-cabin system. The model error of the cable is considered as the unknown disturbances to the cable-cabin system. An extended-states observer (ESO) is used to obtain the effective estimate of the states and unknown disturbance of system. An auto disturbance rejection slide controller is presented with strong robust based on the above result and it’s stability is demonstrated. Numerical result has shown the feasibility and validity of the method.

Key words: Auto disturbance rejection slide controller, Extended state observer, Large radio telescope