A Decoupling Synchronous Control Method of Two Motor or Large Optical Telescope

Aiming at the problem of two motors system of a large optical telescope, a feedforward friction compensated linear active disturbance rejection control (FFLADRC) algorithm is proposed in this article. The algorithm consists of a friction compensated linear active disturbance rejection control (FLADRC) and two nonlinear tracking differentiators (NTDs). The FLADRC realizes the control of the two motors system by decoupling and compensates the friction. The NTDs are used to generate reference position, velocity, and acceleration signals. First, a mathematical model of the two motors system is established. Second, the FFLADRC algorithm is derived using the idea of decoupling. Third, the parameters tuning method of the FFLADRC is given. Fourth, the stability and synchronization mechanisms of the algorithm are analyzed. Finally, the experiments are carried out on a large optical telescope. In the experiments, single motor control, master-slave control, cross-coupling control, and FFLADRC are compared. The results show that FFLADRC has the minimum synchronization error and tracking error, which verifies the effectiveness of the proposed algorithm.