CN210603217U

CN210603217U - Three-dimensional laser scanning calibration block

Info

Publication number: CN210603217U
Application number: CN201921937384.4U
Authority: CN
Inventors: 曹乃承
Original assignee: Nanjing Meixiaojia Technology Co Ltd
Current assignee: Nanjing Meixiaojia Technology Co Ltd
Priority date: 2019-11-12
Filing date: 2019-11-12
Publication date: 2020-05-22
Anticipated expiration: 2029-11-12

Abstract

The utility model aims at providing a three-dimensional laser scanning calibration block. The bottom surface of the base is a plane; the vertical plate is vertical to the base, and is erected on the base; a plurality of calibration columns which are vertical to the plane of the vertical plate and parallel to the bottom surface of the base are arranged on the vertical plate, and the calibration columns are parallel to each other. The spatial coordinates of each calibration post are known. During calibration, the corresponding relation between a plurality of spatial points and the pixels of the imaging plane can be obtained on one image. The utility model discloses a calibration block can once shoot the spatial position coordinate with regard to confirming a plurality of imaging points, and then obtains the spatial coordinate that whole imaging plane's pixel corresponds, has greatly simplified the process of demarcation.

Description

Three-dimensional laser scanning calibration block

Technical Field

The invention relates to a three-dimensional laser scanning calibration device, in particular to a calibration device adopting linear laser scanning.

Background

When linear laser is used for three-dimensional scanning, a calibration block is usually fixed, then a measuring camera and a laser are moved to obtain a plurality of imaging points of positioning points on the calibration block at different positions of an imaging plane of the camera, and calibration of projection positions of a YZ plane on the imaging plane is completed according to the plurality of imaging points. This calibration process requires repeated changes in position between the camera and the calibration block, is time consuming, and introduces additional errors due to the mechanical motion.

Disclosure of Invention

The invention aims to provide a calibration block capable of completing calibration of a three-dimensional laser scanner at one time. The bottom surface of the base is a plane; the vertical plate is vertical to the base, and is erected on the base; a plurality of calibration columns which are vertical to the plane of the vertical plate and parallel to the bottom surface of the base are arranged on the vertical plate, and the calibration columns are parallel to each other. The spatial coordinates of each calibration post are known. During calibration, the corresponding relation between a plurality of spatial points and the pixels of the imaging plane can be obtained on one image.

The calibration block can determine the space position coordinates of a plurality of imaging points by shooting once, so that the space coordinates corresponding to the pixels of the whole imaging plane are obtained, and the calibration process is greatly simplified.

Drawings

FIG. 1 is a front view of a calibration block of the present invention;

FIG. 2 is a top view of a calibration block of the present invention;

FIG. 3 is a front view of another embodiment of a calibration block of the present invention.

Detailed Description

In fig. 1, the calibration block includes a base 1, the bottom surface of which is a plane and can be stably stood in the measurement area. The calibration block comprises a vertical plate 2, and the vertical plate is preferably vertical to the base. The vertical plate is of a thin plate structure and is erected on the base. A plurality of calibration columns 3 which are vertical to the plane of the vertical plate and parallel to the bottom surface of the base are arranged on the vertical plate. The calibration columns are parallel to each other. The calibration columns can be cylinders, prisms, preferably cubes. One lateral edge of the cube is upward, and preferably, the lateral surface of the cube is arranged at an angle of 45 degrees with the bottom surface of the base. The plurality of calibration columns are regularly arranged, the distance between the upward edge of each calibration column relative to the lower surface of the base is known, and the distance between the edges is known. During calibration, the laser irradiates the calibration columns from top to bottom, and the laser forms light spots on the side surfaces of the calibration columns. Because there are two upward sides of each calibration column, in the image shot by the camera, the light spots on the two sides of each calibration column form two linear light bands, and the intersection point of the two light bands is on the side edge. Because the spatial position of the lateral edges is known, the YZ spatial position of the intersection point on each calibration post lateral edge is also known. And the projection point of each intersection point on the camera plane can be determined, so that the projection point on the camera imaging plane corresponds to the YZ coordinate of the real space position. By adopting an interpolation algorithm, the YZ coordinates of the real space position of each pixel on the imaging plane of the camera can be determined. During calibration, the plane of the linear laser beam is preferably perpendicular to the lower surface of the base, preferably perpendicular to the calibration column.

Fig. 2 is a top view of the calibration block of fig. 1.

In fig. 3, the calibration columns of different rows are staggered in the vertical direction, i.e. the calibration columns are not in a vertical column in the vertical direction. The Y-direction distance between the calibration columns close to the base is small, and the Y-direction distance between the calibration columns far away from the base is large. During calibration, the camera shoots light spot images on the calibration block from top to bottom, and the calibration columns arranged in this way can enable the images of the calibration columns in all rows to be more dispersed in the images shot by the camera, so that the identification of light bands in the images is more facilitated.

Claims

1. A three-dimensional laser scanning calibration block is characterized in that:

the calibration block comprises a base, and the bottom surface of the base is a plane;

the calibration block comprises a vertical plate, the vertical plate is vertical to the base, and the vertical plate is erected on the base;

a plurality of calibration columns which are vertical to the plane of the vertical plate and parallel to the bottom surface of the base are arranged on the vertical plate, and the calibration columns are parallel to each other.

2. The calibration block of claim 1, wherein:

the calibration columns are cylinders/prisms.

3. A calibration block according to claim 1 or 2, characterized in that:

the calibration columns of different rows are staggered in the vertical direction.