A multi-scale point cloud data fusion method was proposed in this paper using contour information correspondence to calculate spatial transformation in order to accurately obtain the point cloud information of the main body of large steel truss girder and local bolt holes,so as to be used for virtual assembly of steel joist.Firstly,the point cloud data characterizing the overall information of large-size members and the local information of bolt holes were obtained by combining vertical 3D laser scanning and handheld 3D laser scanning;then,the contour information of the fused parts was extracted based on the point cloud data and the spatial transformation matrix was calculated by using the correspondence of the contour information;finally,the spatial transformation matrix was used for the fusion of the point cloud and the fusion was performed by using the deviation of the main axis and the distance constraints of the closest bolt holes.Finally,the point cloud was fused using the spatial transformation matrix and the fusion effect of the fused model was evaluated by the principal axis direction deviation and the nearest distance constraint,which verifies the accuracy of the fusion method.The deviation of the spindle angle was 0.000 038 4°,the deviation of the torsion angle was 0.011 75°,and the Hausdorff distance was 0.311 mm,which meet the engineering requirements.The method can target the local feature extraction of bars with certain regularity,simplify the information needed for spatial transformation,and provide the data basis for the virtual assembly of steel joist girders.
关键词
三维激光扫描/钢桁梁杆件/点云/空间变换/数据融合
Key words
3D laser scanning/steel joist bars/point cloud/spatial transformation/data fusion
维普
万方数据