装配式建筑点云模型几何特征自动化提取方法研究

Research on Automatic Extraction Method of Geometric Features Based on Prefabricated Building Point Cloud Model

针对传统检测方法无法满足装配式建筑质量精度检验要求的问题,本文提出了一种基于点云模型的装配式建筑预制构件几何尺寸自动化提取方法。首先利用建筑结构空间位置关系及几何特点将典型预制构件点云从整体建筑点云中分割;对构件点云进行特征提取实现尺寸信息的测量;通过求取拟合平面法向量与垂直方向单位向量的夹角检测墙体的垂直度;利用点云切片提取柱中轴线来检测柱体的垂直度;再通过各点到拟合平面的中误差来表示板面平整度。研究以某装配式建筑施工现场采集的点云数据为例,对预制构件点云数据进行离群点剔除与切分,实现点云数据特征自动化提取和测量,测量精度均在95%以上,验证了方法的可行性和有效性。为实现典型预制构件的自动分割、尺寸测量以及参数化管理提供基础。

Traditional inspection methods are difficult to achieve the accurate inspection of the quailty of prefabricated buildings.To solve the problem above,this paper proposes an automatic extraction method of geometric dimensions of prefabricated components of buildings based on point cloud model.The paper conducts this method under the following steps:firstly,the typical prefabricated component point cloud is separated from the overall building point cloud by taking advantage of the spatial location relationship and geometric characteristics of the building structure.Meanwhile,feature extraction of component point cloud is used to measure dimension information and the perpendicularity of the wall is detected by calculating the included angle between the fitting plane normal vector and the vertical direction unit vector.The perpendicularity of the column is detected by extracting the central axis of the column from the point cloud slice.Moreover,the flatness of the board is represented by the mean square error from each point to the fitting plane.The research takes the point cloud data collected from the construction site of a prefabricated building as an example,removes and segments their outliers,after which it can manage the automatic extraction and measurement of point cloud data features.The measurement accuracy,above 95%,verifies the feasibility and effectiveness of the method,which provides a reference for automatic segmentation,dimension measurement and parametric management of typical prefabricated components.