摘要
无人机低空摄影测量与SfM方法作为最新的地貌信息测量手段,受到了越来越多的关注,已经应用于多个研究领域.本文基于无人机摄影测量与SfM技术,应用大疆悟二飞行器、禅思X5S云台相机、Agisoft PhotoScan软件,研究了拍摄高度、拍摄角度和照片重叠度对地貌数据的测量精度,以及对区域三维重建模型效果与生成时间的影响.结果表明:拍摄高度越低,照片重叠度越高,测量结果精度越高.当拍摄高度200m,单点重复次数8.0时,测量结果的空间分辨率4.1cm,水平误差和垂直误差在25cm以内.拍摄角度对结果的水平精度和垂直精度呈现出不同的影响,拍摄角度越垂直于地面,测量结果的水平误差越小,垂直误差越大,反之亦反.另外,在三维模型重建中,拍摄角度越倾斜,模型的侧面纹理越完整清晰,反之模型的侧面纹理越不完整甚至缺失.此外,测量精度与测量的内外业工作量及三维模型的可视化效率之间存在制约,因此需根据具体的需求设计相应的测量方案.本文的研究成果可以为基于无人机与SfM方法的地貌数据采集与三维重建的精度控制和采集方案设置提供定量参考.
There is a growing demand for accurate,high resolution data for geomorphological mapping.This requires the use of precise measurement techniques.Low altitude photogrammetry based on unmanned aerial vehicles(UAV)and structure from motion(SfM)methods is a recent measurement technique which has been applied in many fields.In this paper we studied the influence of acquisition height,acquisition angle and photo overlap on the measurement accuracy of geomorphological data and the effect and generation time of a three-dimensional(3 D)model based on UAV photogrammetry and SfM technology.We used an Inspire-2 aircraft,a Zenmuse X5 S platform camera and Agisoft PhotoScan software.The results showed that higher measurement accuracy was related to lower acquisition height or a higher photograph overlap.When the acquisition height was 200 m and the single point repeat time(SPRT)was 8.0,the spatial resolution of the measured results was 4.1 cm and the horizontal and vertical errors were within 25 cm.The acquisition angle had different effects on the horizontal and vertical accuracy of the results.More perpendicular acquisition angles reduced the horizontal measurement error but increased the vertical measurement error,and vice versa.In addition,more inclined acquisition angles increased the completeness and clarity of the side texture of the 3 D model.Conversely,the side texture of the model was incomplete or even missing with more perpendicular acquisition angles.Furthermore,there was a trade-off between measurement accuracy,the workload for internal and external measurement and the efficiency of 3 D model visualization.Therefore,it is necessary to design the measurement scheme according to the specific application of the data.The results of this paper provide a quantitative reference for geomorphological data acquisition,accuracy control of 3 D reconstruction and the settings for the collection scheme based on UAV and SfM methods.
作者
李文达
闫启明
张尚弘
王龙
刘大为
LI Wenda;YAN Qiming;ZHANG Shanghong;WANG Long;LIU Dawei(Renewable Energy School,North China Electric Power University,Beijing 102206,China;Tianjin Port(Group)Co.,LTD.,Tianjin 300461,China)
出处
《应用基础与工程科学学报》
EI
CSCD
北大核心
2019年第6期1225-1234,共10页
Journal of Basic Science and Engineering
基金
天津港2018年科技计划项目
十三五国家重点研发计划课题(2016YFC0401407).
关键词
地貌数据采集
无人机
SFM
测量精度
三维重建
geomorphological data acquisition
unmanned aerial vehicle(UAV)
SfM
measurement accuracy
3D reconstruction
