三维激光扫描技术作为一种先进的测量手段应用前景十分广阔,但是,在应用其扫描所得的点云数据进行内处理上又遇到了许多技术性的问题。CAD系统处理大量点云数据过程中存在局限性,一旦用CAD系统处理点云时,CAD程序就会出现错误操作提示,...三维激光扫描技术作为一种先进的测量手段应用前景十分广阔,但是,在应用其扫描所得的点云数据进行内处理上又遇到了许多技术性的问题。CAD系统处理大量点云数据过程中存在局限性,一旦用CAD系统处理点云时,CAD程序就会出现错误操作提示,甚至完全停止进程。CloudWorx克服了这些局限性,它避免了直接输入数据,而是利用Cyclone技术作为MicroStation环境下有效管理和解决点云的工具,使MicroStation内点云操作与CAD程序执行再无冲突。本文主要介绍了并且还介绍了CloudWorx模块的功能,并举例就点云数据在CloudWorx for MicroStation软件环境下的处理工作进行了详细的介绍。展开更多
该文以某楼房作为研究对象,探究基于三维激光扫描的建筑立面测绘与三维模型构建技术。在现场踏勘基础上确定测站位置,在测站架设三维激光扫描仪获取点云数据后,依次采取点云配准、点云去噪、数据精简等预处理措施,提高点云数据质量。将...该文以某楼房作为研究对象,探究基于三维激光扫描的建筑立面测绘与三维模型构建技术。在现场踏勘基础上确定测站位置,在测站架设三维激光扫描仪获取点云数据后,依次采取点云配准、点云去噪、数据精简等预处理措施,提高点云数据质量。将点云数据封装后导入Geomagic Studio 2012软件中构建点云模型,经过模型孔洞修补后检测精度,点位精度误差为0.003 m,满足建模要求。将点云格式更改为las格式后输入到AutoCAD软件中绘制立面图,并使用建筑立面图和数码照片得到目标建筑物的三维实体模型,为建筑管理维护提供依据。展开更多
Leaf normal distribution is an important structural characteristic of the forest canopy. Although terrestrial laser scanners（TLS） have potential for estimating canopy structural parameters, distinguishing between le...Leaf normal distribution is an important structural characteristic of the forest canopy. Although terrestrial laser scanners（TLS） have potential for estimating canopy structural parameters, distinguishing between leaves and nonphotosynthetic structures to retrieve the leaf normal has been challenging. We used here an approach to accurately retrieve the leaf normals of camphorwood（Cinnamomum camphora） using TLS point cloud data.First, nonphotosynthetic structures were filtered by using the curvature threshold of each point. Then, the point cloud data were segmented by a voxel method and clustered by a Gaussian mixture model in each voxel. Finally, the normal vector of each cluster was computed by principal component analysis to obtain the leaf normal distribution. We collected leaf inclination angles and estimated the distribution, which we compared with the retrieved leaf normal distribution. The correlation coefficient between measurements and obtained results was 0.96, indicating a good coincidence.展开更多
文摘三维激光扫描技术作为一种先进的测量手段应用前景十分广阔,但是,在应用其扫描所得的点云数据进行内处理上又遇到了许多技术性的问题。CAD系统处理大量点云数据过程中存在局限性,一旦用CAD系统处理点云时,CAD程序就会出现错误操作提示,甚至完全停止进程。CloudWorx克服了这些局限性,它避免了直接输入数据,而是利用Cyclone技术作为MicroStation环境下有效管理和解决点云的工具,使MicroStation内点云操作与CAD程序执行再无冲突。本文主要介绍了并且还介绍了CloudWorx模块的功能,并举例就点云数据在CloudWorx for MicroStation软件环境下的处理工作进行了详细的介绍。
文摘该文以某楼房作为研究对象,探究基于三维激光扫描的建筑立面测绘与三维模型构建技术。在现场踏勘基础上确定测站位置,在测站架设三维激光扫描仪获取点云数据后,依次采取点云配准、点云去噪、数据精简等预处理措施,提高点云数据质量。将点云数据封装后导入Geomagic Studio 2012软件中构建点云模型,经过模型孔洞修补后检测精度,点位精度误差为0.003 m,满足建模要求。将点云格式更改为las格式后输入到AutoCAD软件中绘制立面图,并使用建筑立面图和数码照片得到目标建筑物的三维实体模型,为建筑管理维护提供依据。
文摘Leaf normal distribution is an important structural characteristic of the forest canopy. Although terrestrial laser scanners（TLS） have potential for estimating canopy structural parameters, distinguishing between leaves and nonphotosynthetic structures to retrieve the leaf normal has been challenging. We used here an approach to accurately retrieve the leaf normals of camphorwood（Cinnamomum camphora） using TLS point cloud data.First, nonphotosynthetic structures were filtered by using the curvature threshold of each point. Then, the point cloud data were segmented by a voxel method and clustered by a Gaussian mixture model in each voxel. Finally, the normal vector of each cluster was computed by principal component analysis to obtain the leaf normal distribution. We collected leaf inclination angles and estimated the distribution, which we compared with the retrieved leaf normal distribution. The correlation coefficient between measurements and obtained results was 0.96, indicating a good coincidence.
