直接地理定位技术在大比例尺成图中的应用及精度分析

Application and It’s Accuracy Analysis on Direct Geolocation Technology in Large Scale Mapping

应用与航空遥感像机刚性捷联的高精度惯性测量单元IMU直接测定航空遥感像机的姿态参数,通过DGNSS载波相位差分定位技术获取位置参数,利用联合后处理获得测图所需的每张像片外方位元素直接转入内业测图。利用该法完成的沈阳市1∶500和1∶1000比例尺空三加密结果与外业实测数据进行对比的结果表明,该技术在大量减少外业控制点的同时,符合相应比例尺后续成图作业精度指标,提高了工作效率,为直接地理定位技术在大比例尺基础测绘项目中的应用和推广起到了示范作用。

The high-precision inertial measurement unit IMU,which is rigidly strapped with the aerial remote sensing camera,is used to directly measure the attitude parameters of the aerial remote sensing camera.The position parameters are obtained by the DGNSS carrier phase differential positioning technology,and each image elements of exterior orientation required for the mapping is obtained by joint post-processing.These elements of exterior orientation are directly transferred to the internal mapping.The comparison between the 1∶500 and 1∶1000 scale AT results of Shenyang and the Measured data shows that the technology can reduce the field control points and meet the accuracy of subsequent scale mapping.The indicators have improved work efficiency and played an exemplary role in the application and promotion of direct geolocation technology in large-scale basic mapping projects.