基于激光点云直接比较算法的边坡变形监测技术研究

 利用三维地面激光扫描技术进行边坡变形监测亟需解决多期激光点云数据的比较问题。通过对Hausdorff距离算法的改进，提出基于八叉树结构的点云与点云的精细直接比较算法，实现变形区域多个点云数据的自动比较，减少人工干预，大大提高变形区域激光点云处理效率。基于上述理论和八叉树结构的点云分块管理和存储方法，开发三维可视化激光点云数据处理分析软件LPCP。将该软件应用于阎家沟滑坡的变形监测分析中，经过与固定点监测数据、DEM分析成果和典型断面的激光点云数据的对比验证分析，发现采用点云精细比较算法计算得到的变形区域和位移量准确，计算效率较高。该方法可以推广应用于各种变形的精细比较分析，大大拓宽了激光扫描技术在高精度变形监测中的应用范围。

STUDY OF SLOPE DEFORMATION MONITORING TECHNOLOGY OF PRECISE COMPARISON ALGORITHM BASED ON LASER POINT CLOUD

Comparison of point cloud data in different stages is a problem to be solved in slope deformation monitoring by 3D terrestrial laser scanning technology. Through the improvement of Hausdorff distance algorithm，direct precise comparison algorithm based on octree structure is presented. By this means，automatic comparison of multiple point cloud data in deformation region is achieved，reducing manual intervention and improving the efficiency of point cloud data processing. 3D visual laser point cloud data processing and analysis software LPCP is developed on the basis of block management/storage method by octree structure and the theory mentioned above. Application in the deformation monitoring and analysis of Yanjiagou landslide shows that，the caculated deformation region and displacement by this method is accurate in verified with the fixed point monitoring data，DEM analysis results and laser point cloud data of typical section. Moreover，the algorithm is efficient. The method can be extended to a variety of precise deformation analysis，broadening the application area in deformation monitoring greatly for laser scanning technology.