Abstract
A two-axis antenna-stabilizing-control device which does not need a level sensor was developed. The control incorporates a zero-servo method, which zeros the two gyro outputs by rotating an antenna both with an azimuth motor and an elevation-servo motor. But, a Jimbal-lock and an unlapping of cable occur frequently in high-elevation angle, and large pointing errors resulted from them. We solved the problems by using servo-deflection-correction method and the estimated rewind method.
