The astrodome servo system of the 60-cm telescope of the Peking observatory

Abstract

A tracking system has been installed on the dome of the 60-cm telescope of the Peking observatory. The system uses rotating transformers to transform the coordinates, a relay-operated servo system, with a squirrel-cage induction motor as the executing component. The control system is a non-linear system. In addition to D.C. motor braking, position and velocity feedbacks are used to eliminate self-excited oscillations. The systematic error of the system does not exceed ±1°. The system costs less and is more reliable than a D.C. motor system.