Three-dimensional laser scanner and camera calibration method based on geometric constraint

Abstract

The invention relates to the technical field of three-dimensional point cloud data processing and three-dimensional scene reconstruction, and discloses a three-dimensional laser scanner and camera calibration method based on geometric constraint. The method comprises the following steps: (1) making a calibration board; (2) acquiring a three-dimensional point cloud and a two-dimensional image of the calibration plate; (3) calibrating a camera; (4) calculating a calibration board plane in a camera coordinate system; (5) building point-surface geometric constraint; (6) constructing line-point geometric constraint; (7) constructing surface-surface geometric constraint; (8) calculating a geometric mapping relation of the point cloud and the image. The method has the advantages of deeply analyzing a structure of the three-dimensional point cloud, meanwhile, solving the geometric mapping relation between the point cloud in a laser coordinate system and the image in an image coordinate systemthrough three types of thoughts including the point-surface geometric constraint, the line-point geometric constraint and the surface-surface geometric constraint, making full use of the geometric relation between the calibration board plane and a laser scanning point, and consequently making calibration of the three-dimensional laser scanner and the camera be more accurate and reliable.

Description

technical field [0001] The invention relates to a three-dimensional laser scanner and camera calibration method based on geometric constraints, and belongs to the technical fields of three-dimensional point cloud data processing and three-dimensional scene reconstruction. Background technique [0002] In the process of digitizing the real world, the 3D point cloud data records the geometric properties and position information of the object surface, and the 2D image records the color information and texture information of the object surface. The deep fusion of the two will form an emerging digital Media, that is, 3D color point cloud data, 3D color point cloud data is a further development of 3D point cloud data, which can more accurately represent the real world. In the fusion process of 3D point cloud and 2D image, the calibration of laser scanner and camera is the most critical technology to determine the fusion accuracy. It has strong theoretical significance and applicat...

AI Technical Summary

Problems solved by technology

This method has the following disadvantages: 1) When the 3D point cloud is relatively sparse, it is difficult to accurately calculate the spatial coordinates of the center of the circular hole in the laser coordinate system, which affects the calibration accuracy; 2) The structure of the 3D point cloud is not analyzed. In-depth analysis, excessive reliance on the round hole of the calibration plate to construct geometric constraints, lack of development and utilization of its point-line-surface geometric constraints, the robustness and accuracy of calibration need to be improved

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