CN109540042B - Automobile morphology active vision detection system and method based on unconstrained light plane - Google Patents

Automobile morphology active vision detection system and method based on unconstrained light plane Download PDF

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CN109540042B
CN109540042B CN201910038238.6A CN201910038238A CN109540042B CN 109540042 B CN109540042 B CN 109540042B CN 201910038238 A CN201910038238 A CN 201910038238A CN 109540042 B CN109540042 B CN 109540042B
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camera
laser
coordinate system
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CN109540042A (en
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徐观
陈芳
林慧英
苏建
单红梅
张立斌
刘玉梅
潘洪达
陈熔
戴建国
李晓韬
陈俊伊
沈慧
朱尧平
胡常青
袁静
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Jilin University
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Jilin University
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01BMEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B11/00Measuring arrangements characterised by the use of optical techniques
    • G01B11/24Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
    • G01B11/25Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures by projecting a pattern, e.g. one or more lines, moiré fringes on the object

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Abstract

The invention discloses an automobile morphology active vision detection system and method based on an unconstrained light plane, and aims to solve the problem of automobile morphology active vision detection based on the unconstrained light plane. The active visual detection system for the automobile morphology based on the unconstrained light plane mainly comprises a cylindrical surface target (1), a camera (2), a camera bracket (3), a two-dimensional target plate (4), a laser connecting piece (5) and a laser (6). The active visual detection method for the automobile morphology based on the unconstrained light plane comprises three steps of image acquisition, reconstruction of a laser surface under a two-dimensional target plate (4) coordinate system and reconstruction of vehicle surface characteristic points, and provides an active visual detection system and method for the automobile morphology based on the unconstrained light plane, which are simple in structure and reliable in performance.

Description

Automobile morphology active vision detection system and method based on unconstrained light plane
Technical Field
The invention relates to a measuring device and a measuring method in the field of automobile morphology detection, in particular to an automobile morphology active vision detection system and method based on an unconstrained light plane.
Background
With the continuous development of detection technology in recent years, machine vision gradually becomes a key technology for improving the automobile detection efficiency and ensuring the automobile detection precision. The vehicle morphology detection based on machine vision can provide important research basis for automatic identification of vehicle overrun overload, vehicle type classification, whole vehicle size parameter detection, vehicle information acquisition and reconstruction and the like. The traditional automobile morphology measuring method mainly comprises a contact type measuring method and a fixed type measuring method, however, the contact type measuring method is low in measuring speed and not suitable for measuring large objects, the surface abrasion of the large objects can be caused by the contact of the large objects and the measured objects, and meanwhile, the measuring head can be damaged; fixed detection equipment is fixed can not measure some have the position that shelters from, need make the portal frame, therefore the cost is higher. In order to solve the problems, a non-contact type automobile shape detection method which is high in measurement speed and suitable for measuring large objects and free of strict constraints is very important, an automobile shape active visual detection system and method based on an unconstrained light plane are designed, the position relation between a laser plane and a two-dimensional target plate of the system does not need to be measured repeatedly in the subsequent reconstruction process, and the automobile shape active visual detection system and method can be obtained after calibration, namely the position between the laser plane and the two-dimensional target plate is not strictly constrained, the requirement on the assembly precision between the laser and the two-dimensional target plate during equipment manufacturing is greatly reduced, the production cost of the equipment is reduced, and the application range of the equipment is expanded.
Disclosure of Invention
The invention provides a method and a system with reliable performance, simple structure and simple and convenient operation, aiming at solving the problems of high price, low measurement speed, high cost of fixed detection equipment and the like of contact detection equipment in the process of obtaining the automobile morphology, realizing three-dimensional free reconstruction of the automobile morphology feature points and laying a research foundation for perfecting the automobile morphology detection technology. The method mainly comprises a cylindrical target, a camera bracket, a two-dimensional target plate, a laser connecting piece and a laser. By solving the light plane coordinates of the two-dimensional target coordinate system, the reconstruction of the automobile morphology by adopting an unconstrained laser plane is realized.
The invention is realized by adopting the following technical scheme by combining the attached drawings of the specification:
the automobile morphology active visual detection system based on the unconstrained light plane comprises a cylindrical surface target, a camera bracket, a two-dimensional target plate, a laser connecting piece and a laser;
the cylinder target is placed subaerial, and camera support places subaerial, and the camera passes through the screw hole of bottom and camera support's bolt thread fixed connection, and laser instrument connecting piece steel sheet is put into to two-dimentional target board in the long and thin recess with laser instrument connecting piece welded connection, and the laser instrument inserts in the hole of laser instrument connecting piece steel pipe and is connected with laser instrument connecting piece interference fit.
The cylindrical target in the technical scheme is a semi-cylindrical part made by cutting a standard round pipe along the axial direction, and a regular geometric pattern is attached to the inner surface of the cylindrical target.
The camera in the technical scheme is a wide-angle industrial camera provided with a narrow-band filter.
The camera support in the technical scheme is a universal camera support.
According to the technical scheme, the two-dimensional target plate is a part made of a rectangular steel plate, a regular LED luminous dot matrix is attached to the surface of the two-dimensional target plate, and the wavelength of the LED luminous dot matrix of the two-dimensional target plate is consistent with the band-pass wavelength of a narrow-band filter of a camera.
The laser connecting piece in the technical scheme is formed by welding a steel plate with a long and thin groove and a section of steel pipe.
The laser in the technical scheme is a cylindrical part capable of emitting a laser plane, and the laser wavelength emitted by the laser is consistent with the band-pass wavelength of the narrow-band filter of the camera.
The automobile morphology active visual detection method based on the unconstrained light plane comprises the following specific steps:
the first step is as follows: the method comprises the following steps of image acquisition of an automobile morphology active visual detection method based on an unconstrained light plane:
placing a camera support on the ground, fixing a camera on the camera support, placing a cylindrical target on the ground, fixing a laser on a laser connecting piece, opening the laser, enabling a laser plane emitted by the laser and the cylindrical target to intersect in a laser curve, and acquiring an image by the camera, wherein the image comprises the cylindrical target, a two-dimensional target plate and a projection laser curve formed by the intersection of the laser and the cylindrical target;
the second step is that: reconstructing a laser surface under a two-dimensional target board coordinate system based on an automobile morphology active visual detection method of an unconstrained light plane:
firstly, selecting a camera coordinate system as a fixed global coordinate system, and according to images of the cylindrical target feature points acquired by a camera, world coordinates of the feature points on the cylindrical target
Figure BDA00019446186100000211
To the image coordinates
Figure BDA00019446186100000212
Has a projection relation of
Figure BDA0001944618610000021
Wherein s is1For a scale factor, calculating a projection matrix P from a cylindrical target coordinate system to a camera image coordinate system by adopting a DLT (digital Living transform) methodQITo PQIRQ decomposition is carried out to obtain a rotation matrix R from a cylindrical target coordinate system to a camera coordinate systemRCAnd a translation vector tRC
Then, according to the picture of the laser line on the cylindrical target acquired by the camera, the Steger algorithm is adopted to extract the pictureTwo-dimensional image coordinates of points on projected laser curve
Figure BDA0001944618610000022
The transformation relationship from the cylindrical target coordinate system to the camera coordinate system is
Figure BDA0001944618610000023
Wherein s is2Is a scale factor;
under the cylindrical coordinate system
Figure BDA0001944618610000024
Satisfy the requirement of
Figure BDA0001944618610000025
Wherein r is the cylindrical radius of the cylindrical target,
Figure BDA0001944618610000026
is a vector
Figure BDA0001944618610000027
The coordinates of the points on the laser curve in the cylindrical target coordinate system can be obtained by the above two formulas
Figure BDA0001944618610000028
According to a rotation matrix R from the cylindrical target coordinate system to the camera coordinate systemQCAnd a translation vector tQCAnd coordinates of points on the laser line in the cylindrical target coordinate system
Figure BDA0001944618610000029
The coordinate of the point on the laser line in the camera coordinate system can be obtained by the following formula
Figure BDA00019446186100000210
Points on the laser plane
Figure BDA0001944618610000031
Satisfy the requirement of
Figure BDA0001944618610000032
Obtaining the coordinate pi of the laser plane under the camera coordinate system by SVD decomposition methodC
The rotation matrix R from the two-dimensional target board coordinate system to the camera coordinate system can be solved by a Zhang Zhen you two-dimensional calibration algorithmRCAnd a translation vector tRCThen the homography matrix from the two-dimensional target coordinate system to the camera coordinate system is
Figure BDA0001944618610000033
According to the coordinate pi of the laser plane under the camera coordinate systemCAnd homography matrix H from two-dimensional target board coordinate system to camera 2 coordinate systemRCThe laser plane coordinate under the two-dimensional target plate coordinate system is
Figure BDA0001944618610000034
The third step: reconstructing vehicle surface characteristic points based on an automobile morphology active visual detection method of an unconstrained light plane:
placing a camera support on the ground, fixing a camera on the camera support, enabling an automobile to drive into a view field of the camera, fixing a laser on a laser connecting piece, opening the laser, adjusting the position and the angle of a two-dimensional target plate to enable a laser plane emitted by the laser to intersect with the surface of the automobile on one laser line, collecting an image by using the camera, wherein the image comprises the two-dimensional target plate and a projection laser straight line formed by the intersection of the laser and the surface of the automobile, then placing the two-dimensional target plate on a q-th position, and continuously collecting an image of the q-th position by using the camera, wherein q is 1,2, …, n;
according to the Zhangyingyou two-dimensional calibration algorithm, a rotation matrix R from the two-dimensional target board coordinate system to the camera coordinate system can be obtained and obtainedRC,qAnd a translation vector tRC,qAnd the camera intrinsic parameter K, the homography matrix from the two-dimensional target board coordinate system to the camera coordinate system is
Figure BDA0001944618610000035
The laser plane coordinate pi under the two-dimensional target plate coordinate system calculated by the second stepRAnd homography matrix H from two-dimensional target plate coordinate system to camera coordinate systemRC,qThe laser plane coordinate under the camera coordinate system is
Figure BDA0001944618610000036
Wherein the content of the first and second substances,
Figure BDA0001944618610000037
three-dimensional coordinates of points on the laser line in the camera coordinate system
Figure BDA0001944618610000038
Satisfy the requirement of
Figure BDA0001944618610000041
The image captured by the camera may yield the image coordinates of the two-dimensional target panel and the point on the projected laser line where the laser intersects the vehicle surface
Figure BDA0001944618610000042
Image coordinates
Figure BDA0001944618610000043
And three-dimensional coordinates of points on the laser line in the camera coordinate system
Figure BDA0001944618610000044
The conversion relation is
Figure BDA0001944618610000045
Wherein s is3Is a scale factor, and K is a camera intrinsic parameter;
solving the three-dimensional coordinate of the intersection point of the laser plane and the vehicle body in the camera coordinate system according to the three formulas and the SVD decomposition method
Figure BDA0001944618610000046
And realizing the reconstruction of the three-dimensional characteristic points of the vehicle body.
The invention has the beneficial effects that:
(1) the system has the advantages of wide measurement range, reliable performance, simple structure, simplicity and convenience in operation and wide application range, realizes non-contact and rapid measurement of the appearance of the automobile, and solves the problems of low measurement efficiency, poor convenience and the like of a fixed contact type measurement system.
(2) The combination body formed by the two-dimensional target plate 4 and the laser 6 in the system can be freely scanned, the reconstructed visual field is wider, the scannable position is wider, and the reconstruction method has obvious reconstruction effect on the reconstruction of the regions which are not easy to directly observe, such as the interior of an automobile body.
(3) The camera 2 adopted by the system is a wide-angle industrial camera provided with a narrow-band filter, the range of the obtained visual field is wider, the laser wavelength emitted by the adopted laser 6 and the LED wavelength of the two-dimensional target plate 4 are consistent with the band-pass wavelength of the narrow-band filter of the camera 2, the interference of the ambient light source to the measurement process can be effectively reduced, and the measurement precision is greatly improved.
(4) The position relation between the laser plane and the two-dimensional target plate 4 does not need to be measured repeatedly in the subsequent reconstruction process, and the laser plane and the two-dimensional target plate 4 can be obtained after calibration, namely the position between the laser plane and the two-dimensional target plate 4 is not strictly restricted, so that the assembly precision requirement between the laser 6 and the two-dimensional target plate 4 during equipment manufacturing is greatly reduced, the production cost of the equipment is reduced, and the application range of the equipment is expanded. According to the invention, a projection matrix from a cylindrical target 1 coordinate system to a camera 2 coordinate system is obtained through the projection relation of a cylindrical target 1 to a camera 2 image, and then the world coordinate of a point on a laser line can be obtained according to the projection matrix, the image coordinate of the point on the laser line and a cylindrical formula, so that the coordinate of the point on the laser line under the camera 2 coordinate system is obtained; obtaining the coordinates of the laser plane in the coordinate system of the camera 2 according to the coordinates of the points on the laser plane and in the coordinate system of the camera 2; the coordinates of the laser plane in the coordinate system of the two-dimensional target plate 4 can be obtained from the homography matrix from the coordinate system of the two-dimensional target plate 4 to the coordinate system of the camera 2 and the coordinates of the laser plane in the coordinate system of the camera 2.
Drawings
FIG. 1 is an isometric view of an active vision inspection system calibration for vehicle topography based on an unconstrained optical plane;
FIG. 2 is an isometric view of an active vision inspection system reconstruction of an automobile topography based on an unconstrained light plane;
FIG. 3 is a schematic diagram of a cylindrical target 1 in an unconstrained light plane based active visual inspection system for automotive topography;
FIG. 4 is an isometric view of a camera 2 in an active vision inspection system for vehicle topography based on an unconstrained light plane;
FIG. 5 is an isometric view of a camera mount 3 in an unconstrained light plane based active vision inspection system for automotive topography;
FIG. 6 is an isometric view of a two-dimensional target plate 4, a laser connector 5 and a laser 6 assembly in an automobile morphology active vision detection system based on an unconstrained light plane;
FIG. 7 is a schematic diagram of the calibration of an active vision inspection system for vehicle topography based on an unconstrained optical plane;
FIG. 8 is a schematic diagram of vehicle surface feature point reconstruction for an active vision inspection system for vehicle topography based on unconstrained light planes;
FIG. 9 is a flow chart for solving the coordinates of a laser plane under a two-dimensional target plate 4 coordinate system in an automobile morphology active vision detection system based on an unconstrained light plane;
FIG. 10 is a flow chart of reconstruction of vehicle surface feature points in the camera 2 coordinate system in an unconstrained light plane based active vision inspection system for vehicle topography;
in the figure: 1. the camera comprises a cylindrical surface target, 2. a camera, 3. a camera bracket, 4. a two-dimensional target board, 5. a laser connecting piece and 6. a laser.
Detailed Description
The invention is described in further detail below with reference to the attached drawing figures:
referring to fig. 1 to 6, the active visual inspection system for automobile morphology based on an unconstrained light plane includes a cylindrical target 1, a camera 2, a camera bracket 3, a two-dimensional target plate 4, a laser connector 5, and a laser 6.
The cylindrical target 1 is a semi-cylindrical part made by cutting a standard circular tube along the axial direction, the inner surface is pasted with regular geometric patterns, the cylindrical target 1 is placed on the ground, the camera 2 is a wide-angle industrial camera provided with a narrow-band filter, the camera support 3 is a universal camera support, the camera support 3 is placed on the ground, the camera 2 is fixedly connected with a bolt thread of the camera support 3 through a threaded hole at the bottom, the two-dimensional target plate 4 is a part made of a rectangular steel plate, the surface is pasted with a regular LED light-emitting dot matrix, the laser connecting piece 5 is formed by welding a steel plate with a long and thin groove and a section of steel tube, the two-dimensional target plate 4 is placed in the long and thin groove of the steel plate of the laser connecting piece 5 and is connected with the laser connecting piece 5 in a welding mode, the laser 6 is a cylindrical part capable of emitting a laser, The wavelength of the LED luminous dot array of the two-dimensional target plate 4 is consistent with the band-pass wavelength of the narrow-band filter of the camera 2, and the laser 6 is inserted into the inner hole of the steel pipe of the laser connecting piece 5 and is connected with the laser connecting piece 5 in an interference fit mode.
Referring to fig. 7 to 10, the active visual inspection method for the morphology of the automobile based on the unconstrained light plane can be divided into the following three steps:
the first step is as follows: the method comprises the following steps of image acquisition of an automobile morphology active visual detection method based on an unconstrained light plane:
placing a camera support 3 on the ground, fixing a camera 2 on the camera support 3, placing a cylindrical target 1 on the ground, fixing a laser 6 on a laser connecting piece 5, opening the laser 6, intersecting a laser plane emitted by the laser 6 and the cylindrical target 1 into a laser curve, and acquiring an image by the camera 2, wherein the image comprises the cylindrical target 1, a two-dimensional target plate 4 and a projection laser curve intersecting the laser 6 and the cylindrical target 1;
the second step is that: reconstructing a laser surface under a two-dimensional target board 4 coordinate system based on an automobile morphology active visual detection method of an unconstrained light plane:
firstly, selecting a coordinate system of a camera 2 as a fixed global coordinate system, and according to an image of a characteristic point of a cylindrical target 1 acquired by the camera 2, acquiring a world coordinate of the characteristic point on the cylindrical target 1
Figure BDA0001944618610000061
To the image coordinates
Figure BDA0001944618610000062
The projection relation of
Figure BDA0001944618610000063
Wherein s is1For a scale factor, a projection matrix P from a cylindrical target 1 coordinate system to a camera 2 image coordinate system is solved by adopting a DLT methodQITo PQIRQ decomposition is carried out to obtain a rotation matrix R from a cylindrical target 1 coordinate system to a camera 2 coordinate systemRCAnd a translation vector tRC
Then, according to the picture of the laser line on the cylindrical target 1 acquired by the camera 2, a Steger algorithm is adopted to extract the two-dimensional image coordinates of the points on the projection laser curve in the picture
Figure BDA0001944618610000064
The transformation from the cylindrical target 1 coordinate system to the camera 2 coordinate system is
Figure BDA0001944618610000065
Wherein,s2Is a scale factor;
under the cylindrical coordinate system
Figure BDA0001944618610000066
Satisfy the requirement of
Figure BDA0001944618610000067
Wherein r is the cylindrical radius of the cylindrical target 1,
Figure BDA0001944618610000068
is a vector
Figure BDA0001944618610000069
The coordinates of the points on the laser curve in the coordinate system of the cylindrical target 1 can be obtained by the above two formulas
Figure BDA00019446186100000610
From the rotation matrix R from the cylindrical target 1 coordinate system to the camera 2 coordinate systemQCAnd a translation vector tQCAnd coordinates of points on the laser line in the cylindrical target 1 coordinate system
Figure BDA00019446186100000611
The coordinates of the point on the laser line in the coordinate system of the camera 2 can be obtained as
Figure BDA00019446186100000612
Points on the laser plane
Figure BDA00019446186100000613
Satisfy the requirement of
Figure BDA00019446186100000614
Obtaining the coordinate pi of the laser plane under the camera 2 coordinate system by SVD decomposition methodC
The rotation matrix R from the coordinate system of the two-dimensional target board 4 to the coordinate system of the camera 2 can be solved by a Zhang Zhen you two-dimensional calibration algorithmRCAnd a translation vector tRCThen the homography matrix from the two-dimensional target plate 4 coordinate system to the camera 2 coordinate system is
Figure BDA00019446186100000615
According to the coordinate pi of the laser plane under the camera 2 coordinate systemCAnd homography matrix H from coordinate system of two-dimensional target board 4 to coordinate system of camera 2RCThe laser plane coordinate under the 4 coordinate system of the two-dimensional target board is
Figure BDA0001944618610000071
The third step: reconstructing vehicle surface characteristic points based on an automobile morphology active visual detection method of an unconstrained light plane:
placing a camera support 3 on the ground, fixing a camera 2 on the camera support 3, driving an automobile into a view field of the camera 2, fixing a laser 6 on a laser connecting piece 5, opening the laser 6, adjusting the position and the angle of a two-dimensional target plate 4 to enable a laser plane emitted by the laser 6 to intersect with the surface of the vehicle to form a laser line, collecting an image by using the camera 2, wherein the image comprises the two-dimensional target plate 4 and a projection laser line intersecting with the surface of the vehicle by the laser 6, then placing the two-dimensional target plate 4 on a q-th position, continuously collecting an image of the q-th position by using the camera 2, and q is 1,2, …, n;
according to the Zhangyingyou two-dimensional calibration algorithm, a rotation matrix R from the two-dimensional target board 4 coordinate system to the camera 2 coordinate system can be obtained, and the rotation matrix R from the two-dimensional target board 4 coordinate system to the camera 2 coordinate system can be obtainedRC,qAnd a translation vector tRC,qAnd the camera 2 internal parameter K, the homography matrix from the two-dimensional target plate 4 coordinate system to the camera 2 coordinate system is
Figure BDA0001944618610000072
The laser plane coordinate pi under the two-dimensional target plate 4 coordinate system calculated by the second stepRAnd homography matrix H from coordinate system of two-dimensional target board 4 to coordinate system of camera 2RC,qThe laser plane coordinate under the camera 2 coordinate system is
Figure BDA0001944618610000073
Wherein the content of the first and second substances,
Figure BDA0001944618610000074
three-dimensional coordinates of points on the laser line in the camera 2 coordinate system
Figure BDA0001944618610000075
Satisfy the requirement of
Figure BDA0001944618610000076
The image captured by the camera 2 may yield image coordinates of the two-dimensional target 4 and points on the projected laser line where the laser 6 intersects the vehicle surface
Figure BDA0001944618610000077
Image coordinates
Figure BDA0001944618610000078
And the three-dimensional coordinates of the point on the laser line in the camera 2 coordinate system
Figure BDA0001944618610000079
The conversion relation is
Figure BDA0001944618610000081
Wherein s is3Is a scale factor, and K is an internal parameter of the camera 2;
resolving the laser plane under the 2 coordinate system of the camera according to the three formulas and the SVD decomposition methodThree-dimensional coordinates of intersection with vehicle body
Figure BDA0001944618610000082
And realizing the reconstruction of the three-dimensional characteristic points of the vehicle body.

Claims (7)

1. An automobile morphology active visual detection method based on an unconstrained light plane is characterized by comprising a cylindrical target (1), a camera (2), a camera bracket (3), a two-dimensional target plate (4), a laser connecting piece (5) and a laser (6);
the cylindrical surface target (1) is placed on the ground, the camera support (3) is placed on the ground, the camera (2) is fixedly connected with a bolt thread of the camera support (3) through a threaded hole in the bottom, the two-dimensional target plate (4) is placed in a long and thin groove of a steel plate of the laser connecting piece (5) and is connected with the laser connecting piece (5) in a welding mode, and the laser (6) is inserted into an inner hole of the steel pipe of the laser connecting piece (5) and is connected with the laser connecting piece (5) in an interference fit mode;
the method comprises the following specific steps:
the first step is as follows: the method comprises the following steps of image acquisition of an automobile morphology active visual detection method based on an unconstrained light plane:
placing a camera support (3) on the ground, fixing a camera (2) on the camera support (3), placing a cylindrical target (1) on the ground, fixing a laser (6) on a laser connecting piece (5), opening the laser (6), enabling a laser plane emitted by the laser (6) to intersect with the cylindrical target (1) on a laser curve, and acquiring an image by the camera (2), wherein the image comprises the cylindrical target (1), a two-dimensional target plate (4) and a projection laser curve formed by the intersection of the laser (6) and the cylindrical target (1);
the second step is that: the reconstruction of the laser surface under a two-dimensional target board (4) coordinate system based on the active visual detection method of the automobile morphology of the unconstrained light plane is as follows:
firstly, selecting a coordinate system of a camera (2) as a fixed global coordinate system, and according to an image of a characteristic point of a cylindrical target (1) acquired by the camera (2) and a world coordinate of the characteristic point on the cylindrical target (1)
Figure FDA0002356548120000011
To the image coordinates
Figure FDA0002356548120000012
Has a projection relation of
Figure FDA0002356548120000013
Wherein s is1For a scale factor, a projection matrix P from a cylindrical target (1) coordinate system to a camera (2) image coordinate system is solved by adopting a DLT methodQITo PQIRQ decomposition is carried out to obtain a rotation matrix R from a cylindrical target (1) coordinate system to a camera (2) coordinate systemRCAnd a translation vector tRC
Then, according to the picture of the laser line on the cylindrical target (1) acquired by the camera (2), a Steger algorithm is adopted to extract the two-dimensional image coordinates of the points on the projection laser curve in the picture
Figure FDA0002356548120000014
The conversion relation from the coordinate system of the cylindrical target (1) to the coordinate system of the camera (2) is
Figure FDA0002356548120000015
Wherein s is2Is a scale factor;
under the cylindrical coordinate system
Figure FDA0002356548120000016
Satisfy the requirement of
Figure FDA0002356548120000017
Wherein r is the cylindrical radius of the cylindrical target (1),
Figure FDA0002356548120000018
is a vector
Figure FDA0002356548120000019
The coordinates of the points on the laser curve in the coordinate system of the cylindrical target (1) can be obtained by the above two formulas
Figure FDA00023565481200000110
According to a rotation matrix R from the cylindrical target (1) coordinate system to the camera (2) coordinate systemQCAnd a translation vector tQCAnd the coordinates of the point on the laser line in the coordinate system of the cylindrical target (1)
Figure FDA00023565481200000111
The coordinates of the point on the laser line in the coordinate system of the camera (2) can be obtained as
Figure FDA0002356548120000021
Points on the laser plane
Figure FDA0002356548120000022
Satisfy the requirement of
Figure FDA0002356548120000023
The coordinate pi of the laser plane under the coordinate system of the camera (2) is obtained by an SVD decomposition methodC
The rotation matrix R from the coordinate system of the two-dimensional target board (4) to the coordinate system of the camera (2) can be solved by a Zhang-Zhengyou two-dimensional calibration algorithmRCAnd a translation vector tRCThe homography matrix from the two-dimensional target plate (4) coordinate system to the camera (2) coordinate system is
Figure FDA0002356548120000024
According to laser planeCoordinate pi of camera (2) coordinate systemCAnd a homography matrix H from the coordinate system of the two-dimensional target plate (4) to the coordinate system of the camera (2)RCThe laser plane coordinate under the coordinate system of the two-dimensional target plate (4) is
Figure FDA0002356548120000025
The third step: reconstructing vehicle surface characteristic points based on an automobile morphology active visual detection method of an unconstrained light plane:
placing a camera support (3) on the ground, fixing a camera (2) on the camera support (3), driving an automobile into a view field of the camera (2), fixing a laser (6) on a laser connecting piece (5), opening the laser (6), adjusting the position and the angle of a two-dimensional target plate (4) to enable a laser plane emitted by the laser (6) to intersect with the surface of the vehicle to form a laser line, acquiring an image by using the camera (2), wherein the image comprises the two-dimensional target plate (4) and a projection laser line intersecting the surface of the vehicle by the laser (6), then placing the two-dimensional target plate (4) on a q-th position, and continuously acquiring an image of the q-th position by using the camera (2), wherein q is 1,2, … and n;
according to the Zhang Zhengyou two-dimensional calibration algorithm, a rotation matrix R from the two-dimensional target board (4) coordinate system to the camera (2) coordinate system can be obtained, and then the rotation matrix R from the two-dimensional target board (4) coordinate system to the camera (2) coordinate system can be obtainedRC,qAnd a translation vector tRC,qAnd the camera (2) internal parameter K, the homography matrix from the two-dimensional target board (4) coordinate system to the camera (2) coordinate system is
Figure FDA0002356548120000026
The laser plane coordinate pi under the coordinate system of the two-dimensional target plate (4) calculated by the second stepRAnd a homography matrix H from the coordinate system of the two-dimensional target plate (4) to the coordinate system of the camera (2)RC,qThe laser plane coordinate under the coordinate system of the camera (2) is
Figure FDA0002356548120000031
Wherein the content of the first and second substances,
Figure FDA0002356548120000032
three-dimensional coordinates of points on the laser line in the camera (2) coordinate system
Figure FDA0002356548120000033
Satisfy the requirement of
Figure FDA0002356548120000034
The image obtained by the camera (2) can obtain the image coordinates of the two-dimensional target board (4) and the point on the projection laser line of the laser (6) intersected with the surface of the vehicle
Figure FDA0002356548120000035
Image coordinates
Figure FDA0002356548120000036
And the three-dimensional coordinates of the points on the laser line in the camera (2) coordinate system
Figure FDA0002356548120000037
The conversion relation is
Figure FDA0002356548120000038
Wherein s is3Is a scale factor, and K is an internal parameter of the camera (2);
according to the three formulas and the SVD decomposition method, the three-dimensional coordinate of the intersection point of the laser plane and the vehicle body under the coordinate system of the camera (2) is solved
Figure FDA0002356548120000039
And realizing the reconstruction of the three-dimensional characteristic points of the vehicle body.
2. The active visual inspection method for automobile morphology based on unconstrained light plane as claimed in claim 1, characterized in that the cylindrical target (1) is a semi-cylindrical part made by cutting a standard circular tube along the axial direction, and the inner surface is pasted with a regular geometric pattern.
3. The active visual inspection method of car morphology based on unconstrained light plane according to claim 1, characterized in that said video camera (2) is a wide-angle industrial camera equipped with a narrow-band filter.
4. The active visual inspection method of car topography based on unconstrained light planes according to claim 1, characterized in that said camera mount (3) is a universal camera mount.
5. The active visual inspection method for automobile morphology based on unconstrained light plane as claimed in claim 1, characterized in that the two-dimensional target board (4) is a part made of a rectangular steel plate, and a regular LED light emitting lattice is pasted on the surface, and the wavelength of the LED light emitting lattice of the two-dimensional target board (4) is consistent with the band-pass wavelength of the narrow-band filter of the camera (2).
6. The active visual inspection method of the morphology of an automobile based on an unconstrained light plane according to claim 1, characterized in that the laser connecting piece (5) is formed by welding a steel plate with a long and thin groove and a section of steel pipe.
7. The active visual inspection method of car morphology based on unconstrained light plane according to claim 1, characterized in that said laser (6) is a cylindrical part capable of emitting laser plane, and the laser wavelength emitted by the laser (6) is consistent with the band-pass wavelength of the narrow-band filter of the camera (2).
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CN111380481B (en) * 2019-12-31 2024-06-07 吉林大学 System and method for monocular active visual reconstruction of automobile morphology based on five-point identification
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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102980528A (en) * 2012-11-21 2013-03-20 上海交通大学 Calibration method of pose position-free constraint line laser monocular vision three-dimensional measurement sensor parameters
CN104180775A (en) * 2014-08-05 2014-12-03 吉林大学 Cylindrical surface coordinate based camera calibration target of automobile vision detection system
CN105698699A (en) * 2016-01-26 2016-06-22 大连理工大学 A binocular visual sense measurement method based on time rotating shaft constraint
US9488469B1 (en) * 2013-04-22 2016-11-08 Cognex Corporation System and method for high-accuracy measurement of object surface displacement using a laser displacement sensor
CN106225720A (en) * 2016-09-07 2016-12-14 吉林大学 Automobile pattern based on three-dimensional rectangular coordinate is without kinematic constraint detector
CN209230559U (en) * 2019-01-14 2019-08-09 吉林大学 Based on the automobile pattern Active visual inspection system without constraint optical plane

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102980528A (en) * 2012-11-21 2013-03-20 上海交通大学 Calibration method of pose position-free constraint line laser monocular vision three-dimensional measurement sensor parameters
US9488469B1 (en) * 2013-04-22 2016-11-08 Cognex Corporation System and method for high-accuracy measurement of object surface displacement using a laser displacement sensor
CN104180775A (en) * 2014-08-05 2014-12-03 吉林大学 Cylindrical surface coordinate based camera calibration target of automobile vision detection system
CN105698699A (en) * 2016-01-26 2016-06-22 大连理工大学 A binocular visual sense measurement method based on time rotating shaft constraint
CN106225720A (en) * 2016-09-07 2016-12-14 吉林大学 Automobile pattern based on three-dimensional rectangular coordinate is without kinematic constraint detector
CN209230559U (en) * 2019-01-14 2019-08-09 吉林大学 Based on the automobile pattern Active visual inspection system without constraint optical plane

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