The telescope tracking system is one big-inertia, multivariable, nonlinear, complex and strong coupling mechatronic system which is disturbed by some nonlinear disturbance such as torque ripple, wind disturbance and the cable drag force during the tracking process. In order to suppress the nonlinear disturbance and improve the tracking precision in large astronomical telescope, this paper explores one intelligent fuzzy control algorithm which contains engineers’ rich experimental experience and shows strong inductive ability.

The simulation results show that the fuzzy controller is much stronger than traditional PID controller to suppress the nonlinear interference. The tests in the 1-meter telescope experimental platform also testify that it is very stable and the RMS of position tracking error is only 0.012″ in the superlow tracking speed 0.2″/s. While in the quick tracking speed, 6°/s with the acceleration 5°/s2, the RMS of position tracking error is only near to 1.8″.

In conclusion, by the fuzzy control method designed in this paper, the dynamic response of the telescope tracking system has been improved effectively and the nonlinear interference has also been suppressed strong. What’s more, the tracking accuracy has been improved greatly.