抄録
An antenna- stabilizing control device toward zenith direction employing strapdown 2-axis azimuth/elevation method was developed. In 2-axis method, a gimbal-lock that means lacking of control axis to pitch and roll of ship in high angle of elevation and large pointing errors occur. But, when a ship trembles, a horizontal line exists on a ship plane. Therefore, by coinciding an elevation axis with the horizontal line by rotating the antenna around an azimuth axis, and rotating the antenna axis to zenith direction around elevation axis, the antenna axis can be pointed to zenith direction. As an experiment of above control device, it was confirmed that pointing errors were less than 10° in 90% of working time.
