FAST馈源支撑系统全站仪动态跟踪测量与IMU惯性测量融合研究

The tracking and measuring of FAST feed will be a good choice to solve feed dynamic tracking measurement system is the key technology and difficult in FAST measurement.The feed supporting moves accurately in the 100 meters space scope according to the trajectory planning, requiring for real-time dynamic tracking measurement in the whole course, measurement precision is 5mm, the sampling rate requirements better than 10Hz.Total station is the mainly tracking and measuring equipment of feed support measurements,which can obtain good positioning and attitude determination accuracy. but there are shortcomings, such as out-sync between different measuring equipments,time delay and the of low sampling rate.IMU inertial measurement technology can acquire the real-time position and attitude of motion vector, the dynamic performance is strong, the sampling rate and relative accuracy is high, there are also shortcomings such as zeros and drift error absolute accuracy .Fusion of advantage of high absolute precision of Total station dynamic measuring and the IMU characteristic of high dynamic performance, high relative accuracy will be a good choice to solve dynamic tracking measurement problems in feed supporting measurement.For this, this topic mainly carries out the following research: First, study on distance Intersection of total station instrument; second, research on improvement of IMU measurement, zero and drift model fitting; third, research on the fusion between the total station instrument of dynamic measurement and IMU inertial measurement .

FAST馈源支撑系统跟踪测量是FAST测量的关键技术及难点。馈源支撑系统在上百米空间范围内按规划轨迹进行精确的运动，要求全程实现馈源系统实时动态跟踪测量，测量精度要求达到5mm，采样率要求好于10hz。全站仪是馈源支撑跟踪测量中主要的测量设备，可以获得良好的定位和定姿精度，但是存在不同测量设备无法同步、时滞、采样率低的缺点；IMU惯性测量技术可以实现运动载体实时的位置和姿态，动态性能强、采样率高、相对精度高，但存在系统零点和漂移误差，绝对精度无法保证。将全站仪动态测量技术绝对精度高的优势与IMU测量技术动态性能高、相对精度高的特性相结合，实现这两种测量技术的优势互补和融合，将是一种解决馈源动态跟踪测量的良好选择。为此，本课题主要开展以下研究：一、全站仪动态测量距离交会研究；二、IMU测量零点和漂移模型拟合改进研究；三、全站仪动态测量和IMU惯性测量融合研究。

本课题基于全站仪测距精度高和惯导动态性高数据短期精度高的特点，实现全站仪与惯导的融合测量。首先全面测试分析了全站仪动态测距的特性及误差来源，并提出了误差修正方法，然后测试了惯导测量姿态的特性，根据二者的数据特性设计了基于卡尔曼滤波的融合算法。最后将系统应用到500米口径球面射电望远镜并进行精度和望远镜指向精度测试，位置测量精度优于5mm，望远镜指向精度优于8″，达到了课题预期效果。