Methods of improving closed-loop bandwidth for large telescope control systems

In order to improve the performance of perturbation rejection and the accuracy of tracking for the large telescope, the control system of the telescope needs to have a good dynamic performance, which is due to the closed-loop bandwidth. Firstly, the factors that affect the close-loop bandwith and the dynamics of the telescope control system were analyzed, which were based on the two-mass spring-mass model of the telescope structure, and then two methods including structural filter and acceleration feedback methods which could improve the closed-loop bandwith of the control system, were introduced. Secondly, the application of the structural filter and acceleration feedback methods in the telescope control system was analyzed in detail. Lastly, the related problems that the structural filter was used in the telescope control system were analyzed and the effectiveness of acceleration-feedback control for improving the closed-loop bandwidth was introduced. The experimental results demonstrate that compared with the structural filter method, the acceleration-feedback provides a better technology to improving the closed-loop bandwidth of control system for the large telescopes.