关键词: 露天矿, 布料模拟, 密集点云, 弹性约束, 网格优化, DEM

Abstract: In view of the characteristics of complex terrain,steep pit wall and dense thickets of the pit,it is difficult to obtain a fine DEM by traditional DEM acquisition and processing methods. Referring to the idea of cloth simulation filtering,an elastic constraint filtering algorithm for a pit dense point cloud of oblique photogrammetry is proposed in this paper. Based on the optimization of filtering grid,the concave terrain is differentiated into several elastics according to the height difference. By simulating the deformation process of elastics,the elastic meshes close to the ground is obtained,so as to separate the ground points and generate the DEM. Taking an abandoned mine in Xuzhou as an example,the proposed filtering algorithm is verified by experiments. Compared with the commonly used filtering algorithm,the accuracy of the experimental results is improved by 10. 15%. It performs well in the area with large topographic relief,and the filtering accuracy is 81. 73%. The goodness of fit between the randomly selected ground points and the interpolated elevation is 0. 830,and the root mean square error is 0. 048. The experimental results show that the method proposed in this paper has low data acquisition cost and high efficiency,and can effectively extract the pit ground points,so as to provide the high-precision pit DEM data for the mining area.

Key words: open-pit mine,cloth simulation filtering,dense point cloud,elastic constraint,grid optimization,DEM