Research On Three-dimensional Laser Point Cloud Registration And Photogrammetric Point Cloud Hole Repairing

As a new acquisition technology for spatial data information,three-dimensional laser scanning technology has been widely used in many fields,such as three-dimensional modeling,cultural relic protection,reverse engineering,virtual reality and so on.Due to the presence of obstructions in the three-dimensional laser scanning process or the complex structure of the measured object,the acquired point cloud data will inevitably produce holes,thus affecting the integrity and quality of the digital model.In this paper,based on the principle and characteristics of three-dimensional laser scanning technology and close-range photogrammetry,aiming at the problem of three-dimensional laser scanning point cloud holes,three-dimensional laser point cloud registration and point cloud-hole repair based on images assisted are studied.A point cloud registration algorithm based on an arbitrary rotation angle is proposed.The point cloud generated based on photograms is fused with the original laser point cloud to realize the repair of point cloud holes.Finally,the feasibility of the method is proved by experiments.The specific research contents of this paper are as follows:1.The method of obtaining and preprocessing of point cloud data and image data are introduced.The feasibility of the fusion of three-dimensional laser point cloud data and close-range photogrammetry data is described.2.Describes the principle of image and point cloud data registration.For the arbitrary rotation angle problem in registration,a method of point cloud registration based on strict seven parameters is proposed.3.The method of registration and fusion of point cloud data and image data was studied,and the measurement method of 3D point cloud coordinates based on single camera multi-image was discussed.Through the analysis of registration accuracy,the practicability of the algorithm and the feasibility of fusion of laser point cloud data and image data registration were verified.4.Experiments on laser point cloud hole repairing methods were conducted.Experiments have shown that photogram-based point clouds can effectively repair scanner point cloud holes.Through the precision analysis,the error in the registered point is 0.0155 m,which proves that the point cloud based on photogrammetry can be effectively combined with the laser scanning point cloud.