针对1m太阳望远镜主光学系统光轴与其光电导行系统光轴在望远镜跟踪过程中的相对变化对光电导行跟踪精度的影响,从望远镜的光机电系统结构出发,分析了光电导行闭环跟踪时光轴变化引入的跟踪误差变化规律,提出了光轴变化的检测方法。经过实测表明,光轴的最大相对变化是46″,且变化只与望远镜指向的高度角有关,与望远镜指向的方位角无关,结构重力变形是引起光轴变化的主要因素。在光电导行系统中引入光轴变化的软件修正模型来改善光轴变化引起的光电导行闭环长期跟踪误差。
During a 1 m solar telescope tracking process, the relative change between the telescope optical axis and its auto-guiding system optical axis decreases tracking accuracy. According to the structure of the telescope optical, mechanical and electric control systems, the tracking error of auto guider caused by the change of optical axes is analyzed, and the detection method of the optical axes change is provided. The test results show that the maximum relative change of the optical axes is 46". It varies only with the telescope altitude angles, independent of telescope azimuth angles. The major factor to cause the telescope optical axes change is telescope structure distortion under its gravity. The software correction model of the telescope optical axes which changes in the auto-guiding system is introduced to improve the long-term tracking accuracy decreased by the optical axes change.