Novel target used for point cloud registration, and extraction algorithm thereof

Abstract

The invention discloses a novel target used for point cloud registration, and an extraction algorithm thereof. The novel target comprises at least three reflection boards which intersect at a fixed point of intersection, wherein the reflection boards are fixedly connected in a bracket; two sides of the bracket are rotatably connected to two end parts of a bracket supporting seat through a bracketspindle; the bracket supporting seat is connected with a base through a connecting column; and the point of intersection of the central axis (vv') of the connecting column and the central axis (ll') of the bracket spindle and the fixed point of intersection coincide. By use of the extraction algorithm, the point cloud data is subjected to plane fitting, then, an exceptional point with an overlargedeviation is removed, and finally, the plane equation of a plane where the reflection board is positioned is combined to solve the fixed point of intersection. The novel target has the advantages that the target can be flexibly and simply laid, is suitable for observation in any direction, can be placed on planes including ground and the like, and can provide a large scanning range. When the target is far away from a laser scanner, accuracy losses are few so as to be favorable for improving the registration accuracy of a whole measurement area.

Description

technical field [0001] The invention relates to the technical field of three-dimensional laser scanning measurement, in particular to a novel target for point cloud registration and an extraction algorithm thereof. Background technique [0002] Due to the large size of the project and the wide range of the survey area, in order to obtain the overall point cloud data of the survey area, it is necessary to extract the target center as a feature point, so as to realize the point cloud registration of multiple stations. [0003] At present, there are two kinds of targets commonly used in practical engineering: spherical target and paper target. When the spherical target is far away from the scanner, the number of effective points that can be provided for spherical target fitting is reduced. As a result, the accuracy of obtaining the center coordinates of the spherical target decreases, and as the distance from the scanner increases, the accuracy loss becomes more serious; while ...

AI Technical Summary

Problems solved by technology

[0003] At present, there are two kinds of targets commonly used in practical engineering: spherical target and paper target. When the spherical target is far away from the scanner, the number of effective points that can be provided for spherical target fitting is reduced. As a result, the accuracy of obtaining the center coordinates of the spherical target decreases, and as the distance from the scanner increases, the accuracy loss becomes more serious; while the paper target is farther away from the scanner, its point cloud density, reflection intensity It will weaken, and the accuracy of obtaining the center coordinates of the target will decrease, and as the distance from the scanner increases, the accuracy loss will be more serious

The increase in the extraction error of the target center will cause a large stitching error between two adjacent stations, resulting in a larger cumulative error in the registration of the entire scanning point cloud

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