论文部分内容阅读
天马望远镜(简称TM65 m)所建地区属于软土层,为保证望远镜高指向精度,需要坚实的基础支撑高精度的方位轨道平面。2012年7月~2015年7月,基于精密水准测量系统,采用闭合法对基础沉降及轨道面精度共进行了11次测量。测量数据表明基础沉降逐渐趋于均匀沉降,轨道面均方根误差为0.47 mm。测量结果显示天线的基础沉降和轨道面高程随方位角的变化具有相关性,说明基础沉降直接影响了轨道面的精度。采用实验、仿真和理论相结合的方法分析轨道面不平度引起的天线方位轴在东西和南北方向的误差。首先,线性插值测量的轨道不平度数据,提取某方位角对应的天线方位滚轮6支点的高程,然后将高程差作为约束边界条件施加到有限元模型上,最终仿真分析获得不同方位角下方位轴的倾斜量。同时,利用安装在天线座架上的电子倾斜仪对轨道面不平度进行测量,建立了倾斜仪x和y向输出数据与方位轴倾斜及对应方位角的关系模型,经拟合计算得到方位轴的倾斜量随方位角的变化关系曲线。仿真和理论分析结果具有很好的一致性,轨道面不平度对指向精度的影响在±4″内,分析结果为天线指向模型修正提供了依据。
Pegasus Telescope (referred to TM65 m) built area belongs to the soft soil layer, in order to ensure the telescope high pointing accuracy, you need a solid foundation to support high-precision azimuth orbit plane. From July 2012 to July 2015, based on the precision leveling system, a total of 11 measurements of foundation settlement and orbital plane accuracy were made by the closed method. The measured data show that the foundation settlement gradually tends to settle evenly, and the root mean square error of the orbital plane is 0.47 mm. The measurement results show that the foundation settlement of the antenna and the elevation of the orbital plane are correlated with the azimuth changes, indicating that the foundation settlement has a direct impact on the accuracy of the orbital plane. The error of the azimuth axis of the antenna caused by the unevenness of the track surface in the east, west and north and south directions is analyzed by the combination of experiment, simulation and theory. Firstly, the data of the orbital irregularities measured by linear interpolation are interpolated to extract the elevation of the 6-point bearing of the azimuth bearing wheel corresponding to the azimuth, and then the elevation difference is applied as the constraint boundary condition to the finite element model. Finally, the azimuth angle azimuth axis The amount of tilt. At the same time, using the electronic inclinometer mounted on the antenna mount to measure the unevenness of the track surface, a model of the relationship between the output data of the inclinometer in the x and y directions and the azimuth of the azimuth axis and the azimuth of the azimuth axis is established. The inclination of the amount of change with the azimuth curve. The results of simulation and theoretical analysis are in good agreement. The influence of orbital surface roughness on the pointing accuracy is within ± 4 ", and the analysis results provide the basis for the antenna pointing model correction.