一种检校相机曝光同GPS marktime差的直接方法  

A Method of Measuring Differential Between Camera Exposure Tracking Time and GPS Marktime

作　　者：袁冲 陈永超 张小惠[2] 

机构地区：[1]武汉航天远景科技股份有限公司,湖北武汉430205 [2]武汉警官职业学院,湖北武汉430040

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)

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.

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 

分 类 号：P228.4[天文地球—大地测量学与测量工程]