基于PPK差分技术的无人机倾斜摄影像控点测量精度控制  

Measurement accuracy control for image control points of UAV tilt photography based on PPK difference technology

作　　者：马超 俞佳笠 MA Chao;YU Jiali(Ningbo Almaty Digital Technology Compamy Limited,Ningbo Zhejiang 315042,China)

机构地区：[1]宁波市阿拉图数字科技有限公司,浙江宁波315042

出　　处：《北京测绘》2023年第11期1473-1479,共7页Beijing Surveying and Mapping

基　　金：中央引导地方科技发展基金(YDZX2022019)。

摘　　要：针对目前无人机倾斜摄影测量像控点布设方案不合理、野外测量难度高、图像畸变差大等缺陷,导致测量精度较低,研究基于动态后处理差分技术(PPK)差分技术的无人机倾斜摄影像控点测量精度控制方法。基于PPK差分技术的无人机倾斜摄影及空三测量原理,以某大学新建校区作为无人机航测测试区,设计了三种像控点布设方案,采用摄影测量数据处理软件ContextCapture以及中海达UBASE软件进行PPK后差分技术数据处理,生成数字正射影像图(DOM)和数字高程模型(DEM),通过对比分析不同像控点布设方案的测量精度,实现像控点测量精度控制。实验结果表明:像控点的布设以四周均匀布控、中间点状布控的方式为最佳,可以大幅度提高平面和高程测量的精度,同时像控点布设的密度需要根据实际航测面积进行合理计算,两个像控点之间的距离控制在9000到18000像素,可以实现用最少外业布置达到最佳测量精度的目标。Defects such as unreasonable layout schemes of image control points,high difficulty in field measurement,and large image distortion in tilt photography of unmanned aerial vehicles(UAVs)lead to low measurement accuracy.To address these issues,this paper studied the measurement accuracy control method for image control points of UAV tilt photography based on post-processed kinematic(PPK)difference technology.According to the principles of UAV tilt photography based on PPK difference technology and aerial triangulation,three layout schemes of image control points were designed,with the newly built campus of a university as the testing area for UAV aerial measurement.The photogrammetric data processing software ContextCapture and Zhonghaida UBASE software were used for data processing based on PPK difference technology,so as to generate a digital orthophoto map(DOM)and a digital elevation model(DEM).The measurement accuracy of different layout schemes of image control points was compared to control the measurement accuracy of image control points.The experimental results show that the optimal layout of image control points is to evenly arrange them around the perimeter and make them concentrate in the center in a point shape,which can greatly improve the accuracy of plane and elevation measurements.At the same time,the layout density of image control points needs to be reasonably calculated according to the actual aerial survey area.The distance between two image control points should be controlled between 9000 and 18000 pixels,so as to achieve the best measurement accuracy with minimal field layout.

关 键 词：动态后处理差分技术(PPK) 无人机 倾斜摄影 像控点布设 测量精度控制 数字高程模型 

分 类 号：P231[天文地球—摄影测量与遥感]