无人机倾斜摄影测量在边坡岩体结构面调查中的应用

Application of Unmanned Aerial Vehicle Oblique Photogrammetry to Investigation of High Slope Rock Structure

在高陡边坡岩体结构面的调查中,无人机倾斜摄影测量技术可全面、精确、快捷地获得坡面岩体结构信息。以实际崩塌为研究对象,使用多旋翼单镜头无人机开展航测重建三维边坡模型,利用霍夫法向算法和HSV(hue,saturation,value)算法构建可视化三维岩体结构模型,并对模型进行球形k均值聚类来完成结构面分组提取。研究结果表明,该方法能从三维岩体结构模型中对结构面倾向和倾角进行快速提取和分析,还可在三维空间中对结构面间距、迹长等要素进行准确测量,并根据提取出的结构面构建原位三维岩体结构面模型,为利用倾斜摄影测量调查高陡边坡岩体结构面信息和崩塌灾害形成机理提供了一套可行的解决方案。

Objectives:Traditional remote sensing methods are often limited by the complex terrain and the hardware equipment,which often leads to in-situ measurements that cannot comprehensively,accurately and quickly obtain the slope rock structure data sets.Unmanned aerial vehicle(UAV)oblique photogrammetry technology can obtain comprehensive information on rock structure.Methods:We describe a method for acquiring,visualizing,and extracting three-dimensional information of high slope rock structure based on the dense surface points.The oblique photogrammetric data acquired with UAV is considered and a multi-rotor drone with single-lens is used for aerial surveys to reconstruct the three-dimensional point cloud model of the high slope.The Hough normal algorithm and the HSV(hue,saturation,value)algorithm are used to build a visual three-dimensional rock mass structure model and the model is spherical k-means clustering to complete the automatic extraction of rock structure.Results:From the three-dimensional rock structure analysis,it is possible to quickly extract rock structure characteristics such as orientation,spacing and trace length by rendering the geometry of the three-dimensional slope face.Conclusions:Further research is being carried out in order to build blocky slope masses and identify the kinematic instability of the high limestone cliffs.