CN113432558B - Device and method for measuring irregular object surface area based on laser - Google Patents
Device and method for measuring irregular object surface area based on laser Download PDFInfo
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/28—Measuring arrangements characterised by the use of optical techniques for measuring areas
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- G—PHYSICS
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- G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
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Abstract
The invention relates to measurement of irregular surfaces or contours, in particular to a device and a method for measuring the irregular object surface area based on laser. Compared with the prior art, the method can more accurately obtain the surface area of the irregular object by combining the three-dimensional laser scanning method and the three-dimensional visual reconstruction method.
Description
Technical Field
The invention relates to the measurement of irregular surfaces or profiles, in particular to a device and a method for measuring the surface area of an irregular object based on laser.
Background
Due to the irregular shape of the irregular object, it is often difficult to manually obtain an accurate surface area, and the measured data with large errors has an adverse effect on the application of the data.
The Chinese patent publication No. CN111536908A discloses a device and a method for measuring the surface area of a complex cylinder based on machine vision, the device comprises a desktop combination vision detection support, an adjusting connector, a distance measurement module, a mobile focusing platform, a CCD camera, an illumination module and the like, when in measurement, the measuring device is used for obtaining the height of a workpiece to be measured, detecting surface calibration parameters and shooting an image of the workpiece to be measured, the bottom surface contour and the shape of the workpiece to be measured are obtained based on machine vision technologies such as connected domain screening, edge detection and the like, and the surface area of the complex cylinder workpiece is rapidly calculated according to the parameters. However, the method described by the invention is only suitable for measuring the surface area of a complicated cylinder, is not suitable for irregular objects with more complicated shapes, and has low measurement accuracy.
Disclosure of Invention
In order to overcome one of the defects or shortcomings of the prior art, the invention discloses a device and a method for measuring the surface area of an irregular object based on laser, which adopts the technical scheme that:
the measuring device comprises a three-dimensional laser scanner, and different from the prior art, the measuring device further comprises a three-dimensional camera and a computer, wherein the three-dimensional laser scanner and the three-dimensional camera are respectively fixed on a cantilever and can move up/down, rotate circumferentially and pitch/tilt relative to an object to be measured, and the computer is connected with the three-dimensional laser scanner and the three-dimensional camera.
Furthermore, the three-dimensional laser scanner is a Tianbao TX8, is provided with a laser transmitter, a laser reflection receiver and a quartz clock timer, and is internally provided with a Tianbao RealWorks software; the three-dimensional camera is a monocular or binocular camera; the computer is internally provided with a three-dimensional reconstruction program based on a point cloud base frame and a triangular lattice area accumulation calculation program.
The measuring method comprises the following steps:
a) acquiring 360 degrees multiplied by 317 degrees of field angles and 1000000 points per second of a measured object by using a three-dimensional laser scanner, generating a triangular grid model simulating the measured object by using Tianbao RealWorks software according to the acquired data, and accumulating the area of each triangular grid in the triangular grid model by using a computer to obtain a surface area scanning value M1 of the measured object;
b) acquiring depth images of the measured object from different visual angles by using a monocular camera, generating a triangular grid model simulating the measured object by using a computer to perform point cloud calculation, data fusion and texture mapping on a plurality of depth images, and accumulating the area of each triangular grid in the triangular grid model by using the computer to obtain a measured object surface area reconstruction value M2; or recovering the three-dimensional coordinates of the object by using a binocular camera through parallax and pixel point coordinates for a plurality of depth images so as to generate a triangular mesh model for simulating the measured object, and accumulating the area of each triangular mesh in the triangular mesh model by using a computer to obtain a measured object surface area reconstruction value M2;
c) obtaining the surface area M of the measured object according to the formula (1):
M=（x1M1+x2M2）/（x1+ x2） （1）
in the formula, x1 is the total number of the triangular lattices generated by the Tianbao RealWorks software, and x2 is the total number of the triangular lattices generated by point cloud calculation, data fusion and texture mapping or the total number of the triangular lattices generated by recovering the three-dimensional coordinates of the object through parallax and the coordinates of the pixel points.
Compared with the prior art, the method can more accurately obtain the surface area of the irregular object by combining the three-dimensional laser scanning method and the three-dimensional visual reconstruction method.
Drawings
FIG. 1 is a diagram of the shape of an irregular object for which the embodiment is intended to measure surface area.
Fig. 2 is a triangular mesh model generated after the object of fig. 1 has been scanned by a three-dimensional laser scanner and processed by the tianbao RealWorks software.
Fig. 3 is a triangular grid model generated by the depth map of the object in fig. 1 acquired by the three-dimensional camera through point cloud calculation, data fusion and texture mapping.
Fig. 4 is a schematic view of binocular camera imaging.
Fig. 5 is a schematic diagram of the effect of binocular camera depth variation on other parameters.
Fig. 6 is a schematic diagram of the relationship between the depth invariance of the binocular camera and other parameters.
Detailed Description
The invention is further illustrated by the following specific example.
In order to verify the accuracy of the measurement result of the invention, an irregular object with the shape shown in figure 1 is made by three-dimensional printing, and comprises a regular decagonal cylinder with the side length and the height of 1 decimeter, a cylinder and a hemisphere with the diameter of 1 decimeter, a cube with the side length of 1 decimeter and a triangular cylinder; the square, the triangular column and the cylinder are not overlapped and are all positioned within the range of the top surface of the regular decagonal column.
The theoretical actual surface area Mtheory, in units, of the irregularly shaped object is calculated as follows: square decimeter of
1. Side area =10 × 1 × 1=10 of regular decagonal column
2. The top area/bottom area of the regular decagon pillars =10 × 1 × 1.5389 ÷ 2=7.6946 (the regular decagon together with the diagonal divides the regular 10-sided polygon into 10 isosceles triangles, the base of the triangle =1, the apex angle 36 °, high =1 ÷ 2 ÷ tan (36 ° ÷ 2) ≈ 1.53892)
3. Cylinder side area =3.1416 × 1 × 1=3.1416
4. Cylinder base area = pi r 2=0.7854
5. Hemispherical surface area =4 π r ^2 ÷ 2=4 × 3.1416 × 0.25 ÷ 2=1.570
6. Cube side area =4 × 1 × 1=4
7. Cube top area/bottom area =1 × 1=1
8. Triangular prism side area =3 × 1 × 1=3
9. Triangular prism top area/bottom area =1/2 × 1 × 1 × sin60 ° ≈ 0.433012
Actual surface area mrhysi = side area of the regular decagonal cylinder + base area of the regular decagonal cylinder + top area of the regular decagonal cylinder-cylindrical base area-square base area-triangular prism base area + cylindrical side area + square side area + triangular prism side area + square top area + hemisphere surface area =10+7.6946+7.6946-0.7854-1-0.433012+3.1416+4+3+ 1.570= 36.88228.
The invention relates to a device for measuring irregular object surface area based on three-dimensional laser scanning and three-dimensional visual reconstruction, which comprises a three-dimensional laser scanner, and is characterized by further comprising a three-dimensional camera and a computer, wherein the three-dimensional laser scanner and the three-dimensional camera are respectively fixedly arranged on a cantilever and can move up and down, rotate circumferentially and pitch/pitch relative to an object to be measured, and the computer is connected with the three-dimensional laser scanner and the three-dimensional camera.
The three-dimensional laser scanner of the embodiment is a commercially available Tianbao TX8 model, and is provided with a laser transmitter, a laser reflection receiver and a quartz clock timer, and Tianbao RealWorks software is built in, and data acquired by the Tianbao TX8 can be directly imported into the Tianbao RealWorks software and the Tianbao Scan Explorer software. Through the cooperation of Tianbao TX8 and Tianbao RealWorks, an efficient data stream capable of being imported into mainstream CAD software can also be provided. Tianbao TX8 is an ideal tool for acquiring real scene detail data. The device can perform high-speed measurement without losing the measurement range and precision, and provides high-density three-dimensional point cloud data required by design and analysis professionals. The Tianbao TX8 has a 360 × 317 field of view and a data acquisition speed of 1000000 points per second, and can complete a typical measurement task in 3 minutes. TX8 can keep high-precision measurement in the whole range of 120 meters, and the range can be extended to 340 meters by matching with an optional upgrading configuration.
The computer of the device is internally provided with a three-dimensional reconstruction program based on a point cloud base frame and a triangular lattice area accumulation calculation program. The three-dimensional camera is a monocular or binocular camera;
the measured object surface area scan value M1 of the irregular object is obtained by the three-dimensional laser scanner as follows:
the method for obtaining the triangular grid model of the irregular object by using the three-dimensional laser scanner is the prior art, in the embodiment, the number of the triangular grid models simulating the irregular object generated by the Tianbao RealWorks software is 3627, and the surface area scanning value M1 of the measured object is 38.45234 by accumulating the area of each triangular grid in the triangular grid model by using a computer.
How to obtain the measured object surface area reconstruction value M2 by using a monocular camera or a binocular camera is described as follows:
the generation of a triangular mesh model simulating a measured object by using a monocular camera to perform point cloud calculation, data fusion and texture mapping on a plurality of depth images is the prior art, and the following description is provided for further understanding of the technical scheme of the present invention.
The depth image after the point cloud computing preprocessing has two-dimensional information, the value of the pixel point is depth information, the linear distance between the surface of the object and the Kinect sensor is represented, and the linear distance is in millimeters. Based on the imaging principle of the camera, the conversion relationship between the world coordinate system and the image pixel coordinate system can be calculated according to the following formula:
and u and v are any coordinate points in an image coordinate system. u0 and v0 are respectively the central coordinates of the image. xw, yw, zw represent three-dimensional coordinate points in the world coordinate system. zc represents the z-axis value of the camera coordinates, i.e. the object-to-camera distance. R and T are respectively a 3x3 rotation matrix and a 3x1 translation matrix of the external reference matrix.
Overall the image to camera conversion is:
(u 0, v 0) is the coordinate of the origin of the image coordinate system (image center) in the pixel coordinate system (with the upper left corner as the origin), and dx and dy are the physical dimensions of each pixel in the x and y directions of the image plane, respectively. f is the focal length (distance of the image plane from the origin of the camera coordinate system). M is called an internal reference matrix, and is understood that each value in the matrix is only related to the internal parameters of the camera and does not change along with the position change of the object. Where fx, fy is in units of one (number of pixels). The transformation from world coordinate system to pixel coordinate system (without distortion taken into account) is summarized with a graph:
the existing algorithm TSDF is adopted in data fusion, and the method only stores a plurality of layers of voxels close to the real surface, but not all the voxels, so that the redundant points of the model are reduced.
Finally, texture mapping is the generation of a surface, and in order to construct a visual isosurface of an object, the original gray-scale volume data is directly processed by a common voxel level method. The existing MC (moving cube) method is used. The marching cubes method first stores eight adjacently located data in a data field at eight vertices of a tetrahedral voxel, respectively. For two end points of an edge on a boundary voxel, when one of the values is greater than a given constant T and the other is less than T, there must be a vertex of the iso-surface on the edge. And then calculating the intersection points of twelve edges in the voxel and the isosurface, and constructing triangular patches in the voxel, wherein all the triangular patches divide the voxel into two areas, namely an isosurface area and an isosurface area. And finally, connecting the triangular patches of all voxels in the data field to form an isosurface. Merging the iso-surfaces of all cubes results in a complete three-dimensional surface.
The present invention provides a method for generating a triangular grid model simulating a measured object by recovering three-dimensional coordinates of the object from a plurality of depth images through parallax and pixel point coordinates by using a binocular camera.
As shown in fig. 4, P is a certain point on the object to be measured, OR and OT are optical centers of two cameras, imaging points of the point P on two cameras photoreceptors are P and P '(an imaging plane of the camera is placed in front of a lens after being rotated), f is a focal length of the camera, B is a center distance of the two cameras, Z is depth information that we want to obtain, and if a distance from the point P to the point P' is dis:
according to the similar triangle principle:
the following can be obtained:
the conclusions can be drawn from fig. 5 and the following table:
depth changes (EG' EFI (AB + CD) or H to EF distance) can result in changes in AB, CD and AB + CD, and the changes in AB, CD are not emphasized too much here, only AB + CD will be discussed, for reasons that will be mentioned later. As the depth becomes larger, AB + CD becomes progressively smaller. From the formula AC = EF-AB-DC, given Z as depth, AC/EF = (Z-EG)/Z can thus be derived.
As is evident from fig. 6 and the following table:
as long as the depth is constant, AB + CD will not change, and it can be seen that the depth and AB alone have no direct relationship to CD, but only to the sum of the two.
The disparity between AB + CD and the same distance is ideal. AB + DC = XR-XT note that AB DC is here vector-summed (AB + DC = (Bx-Ax) + (Cx · Dx) [ (Bx is the midpoint x of the left image, Dx is the midpoint x Ax of the right image, and Cx is the x-coordinate of the same feature point in both figures) ] XR-XT = XRx-XTx (XRx and XTx are the x-coordinates of the same feature point in both figures, respectively).
Remarking: the formulas here all assume that the camera is horizontal and if the camera is vertical, the y coordinate should be used.
The number of the triangular mesh models simulating the measured object generated by point cloud calculation, data fusion and texture mapping is 2829, and the surface area reconstruction value M2 of the measured object is 34.8824 by accumulating the area of each triangular mesh in the triangular mesh models through a computer.
The surface area M of the measured object is obtained by using the following formula (1):
M=（x1M1+x2M2）/（x1+ x2）=（3627×38.45234+2829×34.8824）/（3627+2829）=36.8766
the error between each value and the theoretical value is shown in the following table:
from the table, the errors of the measured values and the actual theoretical values obtained based on three-dimensional laser scanning or three-dimensional visual reconstruction are about 5%, while the errors of the measured values and the actual theoretical values obtained by the measuring method are about 0.01%, so that the accuracy is greatly improved, and the method is worthy of wide popularization.
Claims (1)
1. A method for measuring irregular object surface area based on laser comprises a three-dimensional laser scanner, a three-dimensional camera and a computer, and is characterized in that the three-dimensional laser scanner and the three-dimensional camera are respectively fixed on a cantilever and can move up/down, rotate circumferentially and pitch/tilt relative to an object to be measured, and the computer is connected with the three-dimensional laser scanner and the three-dimensional camera; the three-dimensional laser scanner is a Tianbao TX8, is provided with a laser transmitter, a laser reflection receiver and a quartz clock timer, and is internally provided with a Tianbao RealWorks software; the three-dimensional camera is a monocular or binocular camera; the computer is internally provided with a three-dimensional reconstruction program based on a point cloud base frame and a triangular lattice area accumulation calculation program; it is characterized in that the preparation method is characterized in that,
the method comprises the following steps:
a) acquiring 360 degrees multiplied by 317 degrees of field angles and 1000000 points per second of a measured object by using a three-dimensional laser scanner, generating a triangular grid model simulating the measured object by using Tianbao RealWorks software according to the acquired data, and accumulating the area of each triangular grid in the triangular grid model by using a computer to obtain a surface area scanning value M1 of the measured object;
b) acquiring depth images of the measured object from different visual angles by using a monocular camera, generating a triangular grid model simulating the measured object by using a computer to perform point cloud calculation, data fusion and texture mapping on a plurality of depth images, and accumulating the area of each triangular grid in the triangular grid model by using the computer to obtain a measured object surface area reconstruction value M2; or recovering the three-dimensional coordinates of the object by using a binocular camera through parallax and pixel point coordinates for a plurality of depth images so as to generate a triangular mesh model for simulating the measured object, and accumulating the area of each triangular mesh in the triangular mesh model by using a computer to obtain a measured object surface area reconstruction value M2;
c) obtaining the surface area M of the measured object according to the formula (1):
M=（x1M1+x2M2）/（x1+ x2） （1）
in the formula, x1For the total number of triangles, x, generated by the Tianbao RealWorks software2And generating the total number of the triangular lattices by the total number of the triangular lattices generated by point cloud calculation, data fusion and texture mapping or restoring the three-dimensional coordinates of the object by the parallax and the pixel point coordinates.
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Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1640688A1 (en) * | 2004-09-24 | 2006-03-29 | Konrad Maierhofer | Method and Apparatus for Measuring the Surface on an Object in three Dimensions |
| CN102200433A (en) * | 2011-02-25 | 2011-09-28 | 北京农业信息技术研究中心 | Device and method for measuring leaf area based on computer vision |
| CN103278090A (en) * | 2013-05-14 | 2013-09-04 | 陕西科技大学 | Visual measurement method for volume of irregular object |
| CN104359418A (en) * | 2014-11-28 | 2015-02-18 | 南京理工大学 | Laser and video infused automatic railway snow depth multi-point measuring device and method |
| CN104596447A (en) * | 2015-01-26 | 2015-05-06 | 上海出入境检验检疫局机电产品检测技术中心 | Ornament surface area rapid detection method and system based on image analysis technique |
| CN105302151A (en) * | 2014-08-01 | 2016-02-03 | 深圳中集天达空港设备有限公司 | Aircraft docking guidance and type recognition system and method |
| CN108803621A (en) * | 2018-07-27 | 2018-11-13 | 广州大学 | A kind of steel rail welding line reconditioning robot path planning method |
| CN213041993U (en) * | 2020-08-07 | 2021-04-23 | 宁波兰辰光电有限公司 | Magnetic ring height and size comprehensive measurement equipment |
| CN112833784A (en) * | 2021-01-04 | 2021-05-25 | 中铁四局集团有限公司 | Steel rail positioning method combining monocular camera with laser scanning |
| CN113093216A (en) * | 2021-06-07 | 2021-07-09 | 山东捷瑞数字科技股份有限公司 | Irregular object measurement method based on laser radar and camera fusion |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3602965B2 (en) * | 1998-06-09 | 2004-12-15 | 株式会社ミツトヨ | Non-contact three-dimensional measurement method |
| US6832577B2 (en) * | 2002-07-08 | 2004-12-21 | Dimension Bond Corporation | Apparatus and method for simultaneously coating and measuring parts |
| JP6930270B2 (en) * | 2017-08-01 | 2021-09-01 | 凸版印刷株式会社 | Issuing device for irregularly shaped non-contact IC articles |
-
2021
- 2021-08-25 CN CN202110979187.4A patent/CN113432558B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1640688A1 (en) * | 2004-09-24 | 2006-03-29 | Konrad Maierhofer | Method and Apparatus for Measuring the Surface on an Object in three Dimensions |
| CN102200433A (en) * | 2011-02-25 | 2011-09-28 | 北京农业信息技术研究中心 | Device and method for measuring leaf area based on computer vision |
| CN103278090A (en) * | 2013-05-14 | 2013-09-04 | 陕西科技大学 | Visual measurement method for volume of irregular object |
| CN105302151A (en) * | 2014-08-01 | 2016-02-03 | 深圳中集天达空港设备有限公司 | Aircraft docking guidance and type recognition system and method |
| CN104359418A (en) * | 2014-11-28 | 2015-02-18 | 南京理工大学 | Laser and video infused automatic railway snow depth multi-point measuring device and method |
| CN104596447A (en) * | 2015-01-26 | 2015-05-06 | 上海出入境检验检疫局机电产品检测技术中心 | Ornament surface area rapid detection method and system based on image analysis technique |
| CN108803621A (en) * | 2018-07-27 | 2018-11-13 | 广州大学 | A kind of steel rail welding line reconditioning robot path planning method |
| CN213041993U (en) * | 2020-08-07 | 2021-04-23 | 宁波兰辰光电有限公司 | Magnetic ring height and size comprehensive measurement equipment |
| CN112833784A (en) * | 2021-01-04 | 2021-05-25 | 中铁四局集团有限公司 | Steel rail positioning method combining monocular camera with laser scanning |
| CN113093216A (en) * | 2021-06-07 | 2021-07-09 | 山东捷瑞数字科技股份有限公司 | Irregular object measurement method based on laser radar and camera fusion |
Non-Patent Citations (3)
| Title |
|---|
| Laser cutting of irregular shape object based on stereo vision laser galvanometric scanning system;Li Qi等;《Optics and Lasers in Engineering》;20150531;第68卷;第180-187页 * |
| 一种求解三维激光扫描后不规则体的体积及表面积方法;王伟等;《测绘与空间地理信息》;20190831;第42卷(第8期);第172-175页 * |
| 三维激光扫描仪在不规则实体表面积计算中的应用;周晓卫等;《矿山测量》;20200630;第48卷(第3期);第17-19、21页 * |
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