摘要
在GPS辅助空中三角测量中,GPS精度对所需像控点的密度和后期成果精度有重要影响,特别是对无人机免像控高精度测绘,GPS精度对后期成果精度有决定性地影响。研究表明机载GPS记录相机曝光点的定位精度除了跟GPS自身有关之外,还同相机与差分GPS之间的同步性有关。准确测定相机曝光同差分GPS记录时间点(marktime)之差能有效提高对相机曝光点的定位精度。当前一般采用事后估计法来测定时间差,本文提供一种先验检校方法来直接测定相机曝光同GPS marktime之差,并用实验数据采用立体测图方式验证了本方法的可靠性。
In the GPS-supported aerial triangulation,the accuracy of GPS has an influence on the density of control points and the latter accuracy of results,especially for no-control-points high accurate measurement. The accuracy of GPS defines the finial outputs. As the research manifests that the accurate position is related with itself as well as the synchronism of D-GPS. Measuring the differential between camera exposure tracking-time and GPS marktime improves the position of camera exposure. Presently,besides adopting latter method of estimation,this article provides pre-calibration method that measures the differential GPS marktime and camera exposure tracking-time,following by experiment data from stereo mapping to verify its reliability.
出处
《城市勘测》
2018年第1期55-59,共5页
Urban Geotechnical Investigation & Surveying
基金
国家自然科学基金项目(41501503)
关键词
免像控
高精度
曝光时间差
GPS辅助空中三角测量
检校
no-control-points
high-precision
time difference
GPS-supported aerial triangulation
check
作者简介
袁冲（1983-）,男,工程师,主要研究低空无人机测绘遥感技术和计算机视觉技术
