CN207946065U - Bundled round steel multi-vision visual identifying system - Google Patents
Bundled round steel multi-vision visual identifying system Download PDFInfo
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- CN207946065U CN207946065U CN201820479469.1U CN201820479469U CN207946065U CN 207946065 U CN207946065 U CN 207946065U CN 201820479469 U CN201820479469 U CN 201820479469U CN 207946065 U CN207946065 U CN 207946065U
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Abstract
Bundled round steel multi-vision visual identifying system includes:Light source(1), main phase machine(2), main phase machine and light source bracket(3), auxiliary camera(4), auxiliary camera support(5), computer(6)And scaling board(7), the image information of multiple angles of bundled round steel end face can be obtained using the system, effectively solve the image occlusion issue caused by end face is not spent concordantly.
Description
Technical field
The present invention relates to a kind of object visual identifying systems, identify and count more particularly, to a kind of bundled round steel end face
Multi-vision visual identifying system.
Background technology
Round steel is the major product of present steel industry, even more the important production and processing raw material of industrial circle.In difference
Industry requires also to be different for extraordinary round steel, steel production enterprise produce and be supplied to the round steel of down-stream enterprise often with
Bundled form occurs.For the ease of the management and control of extraordinary round steel, need to the total weight and radical of bundled round steel carry out statistics and
Mark.According to the investigation to certain domestic special steel manufacturing enterprise, generally used in the production and management of domestic bundled round steel at present pair
Bundled round steel weighs to obtain bundle weight, single round steel passes through type information(Including material, density, diameter and length)Calculate list
Then the root weight of root round steel obtains the radical of bundled round steel with bundle weight divided by root weight.It can be seen that the prior art is bundled
The radical information of round steel is that " calculating " obtains, and is not in calculating mistake generally for the big stick-means of intimidation being relatively large in diameter, and for straight
The smaller spillikin the method for diameter is it is possible that radical mistake of statistics.
In patent [CN201610193685.5], it is proposed that a kind of bundled round steel end face center coordinate of view-based access control model
System and method are obtained, the end face of bundled round steel is identified with monocular vision and carries out plane positioning.In patent
In [CN201710878572.3], it is proposed that a kind of round steel end face binocular visual positioning method based on major-minor eye, with binocular vision
The end face of bundled round steel is identified and carries out space orientation in feel system, but also can record the quantity of round steel, realizes meter
Number function.But the method mentioned in two above patent be mainly used for the end face of round steel is identified when bundled big stick-means of intimidation labeling and
Positioning, is not suitable for spillikin.Currently, although there is arrangement station when round steel bundling, but the end face of bundled round steel still have it is certain
It does not spend concordantly, will produce and blocked so as to cause visual identity failure, to generate when in this way for spillikin with visual imaging
Miscount.Therefore, invent it is a kind of can effectively solve the problem that image block cause the vision system of bundled round steel miscount for
Solve the problems, such as that produce reality is particularly important.
Invention content
Based on the above reason, the present invention is directed to propose a kind of bundled round steel multi-vision visual identifying system.
The present invention bundled round steel multi-vision visual identifying system include:Light source 1, main phase machine 2, main phase machine and light source bracket 3,
Auxiliary camera 4, auxiliary camera support 5, computer 6 and scaling board 7.Light source 1 is annular light source, annular of the main phase machine 2 in annular light source 1
In hole and light source 1 is coaxially arranged, and light source 1 and main phase machine 2 are installed and fixed by main phase machine and light source bracket 3.Auxiliary camera 4 passes through
Auxiliary camera support 5 installs and fixes.The axis radial equipartition of 3 auxiliary cameras 4 and camera support 5 around main phase machine 2.Main phase machine
2 and 3 auxiliary cameras 4 form multi-vision visual image collecting device.When installation, make light source 1 by adjusting main phase machine and light source bracket 3
Axis with main phase machine 2 makes 3 auxiliary phases perpendicular to the center of the end face of bundled round steel by adjusting 3 auxiliary camera supports 5
The axis of machine 4 and the axis of main phase machine 2 intersect at a point, and the focus is made to be located at the theoretical center position of bundled round steel entirety end face
It sets.2,3 light source 1, main phase machine auxiliary cameras 4 are connected with computer 6 by cable.Computer 6 is equipped with visual identity and processing
Program, and corporate intranet is accessed, production information can be read in real time online.Scaling board 7 is used for main phase machine 2 and 3 auxiliary cameras 4
Vision calibration, calibration process need to only carry out primary after this system is correctly installed.
The present invention advantageous effects include:
(1)The image information of multiple angles of bundled round steel end face can be obtained, is effectively solved because concordantly degree is not led for end face
The image occlusion issue of cause;
(2)Result of calculation in system meeting comprehensive visual recognition result and company information library, conclusion reliability higher.
Description of the drawings
Fig. 1 is the structural schematic diagram of the bundled round steel multi-vision visual identifying system of the present invention;
Fig. 2 is bundled round steel multi-vision visual identifying system main phase machine 2 of the invention and 34 radial arrangement schematic diagrames of auxiliary camera;
Fig. 3 is that the bundled round steel multi-vision visual identifying system main phase machine 2 of the present invention and 34 axis direction of auxiliary camera arrangements are shown
It is intended to.
Specific implementation mode
Structure and the concrete operations of present system are introduced in conjunction with attached drawing 1-3.
The present invention bundled round steel multi-vision visual identifying system include:Light source 1, main phase machine 2, main phase machine and light source bracket 3,
Auxiliary camera 4, auxiliary camera support 5, computer 6 and scaling board 7.Light source 1 is annular LED light source, and main phase machine 2 is in annular light source 1
In looping pit and light source 1 is coaxially arranged, and light source 1 and main phase machine 2 are installed and fixed by main phase machine and light source bracket 3.Auxiliary camera 4
It is installed and fixed by auxiliary camera support 5.3 auxiliary cameras 4 and camera support 5 are pressed from both sides around the axis radial equipartition of main phase machine 2
Angle is 120 °.Main phase machine 2 and 3 auxiliary cameras 4 form multi-vision visual image collecting device.When installation, by adjust main phase machine and
Light source bracket 3 makes the axis of light source 1 and main phase machine 2 perpendicular to the center of the end face of bundled round steel, by adjusting 3 auxiliary phases
Machine support 5 makes the axis of 3 auxiliary cameras 4 and the axis of main phase machine 2 intersect at a point, and the focus is made to be located at bundled round steel entirety
The theoretical center position of end face.2,3 light source 1, main phase machine auxiliary cameras 4 are connected with computer 6 by cable.Computer 6 is installed
There are visual identity and processing routine, and access corporate intranet, production information can be read in real time online.Scaling board 7 is for leading
The vision calibration of camera 2 and 3 auxiliary cameras 4, calibration process need to only carry out primary after this system is correctly installed.
Bundled round steel multi-vision visual system using the present invention, which is identified and counted for bundled round steel, to be included the following steps:
(1)The good bundled round steel multi-vision visual identifying system of installation and debugging;
(2)Arrange scaling board;
(3)Monocular calibration is carried out to main phase machine and auxiliary camera, withdraws scaling board after the completion;
(4)Image Acquisition, image enhancement processing and image binaryzation processing are carried out respectively to main phase machine and auxiliary camera;
(5)The identification of image circle, centralized positioning are carried out respectively to main phase machine and auxiliary camera;
(6)The online radical and diameter information for reading bundled round steel in company information library in real time;
(7)Synthesis is carried out according to the diameter information of round steel to the round steel end face center point that main phase machine and auxiliary camera obtain to sentence
It is disconnected, it determines the radical and reliability that bundled round steel visual identity goes out and carries out central point distance verification;
(8)Result of calculation in the visual identity result and company information library of more bundled round steel radical, comprehensive descision.
If the bundled round steel end face diameter of certain special steel manufacturing enterprise is about 300mm, setting position measurement accuracy 0.5mm,
Camera and round steel end face distance about 1000mm.Pixel is estimated first, and measured object is the circle of 300mm, and camera target surface is usually
4:3 rectangle, in order to which by object, all intake target surfaces should be reference with target surface most bond length, pixel should be greater than 300/0.5=
600,1/3 inch of Daheng's CCD camera MER-125-30UM target surfaces size can be selected according to the pixel of estimation(4.8×3.6mm),
Resolution ratio is 1292 × 964, and pixel dimension isu=3.75 μm of camera verifies precisionT, can be according to formulaT=u/βIt calculates, whereinβ=3.6/300 is camera lens magnifying power, is computedT=0.31mm meets required precision;Focal lengthfFormula can be passed throughf=L/(1+1/β)
It calculates, whereinL=1000mm, is computedf=11.8mm, optional focal length is the camera lens of 12mm, such as Daheng's TG4Z2816FCS camera lenses.
Light source selects the LED annular light sources of the model VR144-B of thousand Electro-optical Technology, INC. (US) 62 Martin Road, Concord, Massachusetts 017 of Shanghai side production, the mating electricity with light source
Source model VPD-24S.In view of filtering veiling glare, light source is configured to blue light, camera Selecting Complete Set blue filter, model
BP470-30.5.Main phase machine and 3 auxiliary cameras are all made of identical industrial camera and match blue filter, and illumination uses annular LED
Blue-light source, using industrial personal computer as system control unit.
1, the good bundled round steel multi-vision visual identifying system of installation and debugging
Bundled round steel is placed in visual identity and counts on station, is horizontally arranged, and whole round steel end face ensures not spend concordantly
20mm.System makes main phase in use, bundled round steel multi-vision visual identifying system to be placed in the front of bundled round steel entirety end face
It is whole that the crossing point of axes of the coincidence of the ideal axis of the axis of machine 2 and bundled round steel, main phase machine 2 and 3 auxiliary cameras 4 is located at bundled round steel
The center in body end face.The array circular diameter of 3 auxiliary cameras is set as steel bundle diameter, i.e. 300mm.
2, scaling board is arranged
Arrangement scaling board 7 is located on the ideal plane of bundled round steel entirety end face, and makes main phase machine 2 and 3 auxiliary cameras 4
Axis focuses on the center of scaling board 7.
3, monocular calibration is carried out to main phase machine and auxiliary camera, withdraws scaling board after the completion
Delaunay subdivision triangular interpolation value standardizations are a kind of method of two-dimensional calibrations, for determining world coordinates
Transformational relation between system and image coordinate system.Select dot matrixes type target as scaling board, using in each border circular areas
The heart is as characteristic point, and stated accuracy is than other types scaling board higher.
The step of Delaunay subdivision triangular interpolation value standardizations:
1)Plane target drone is placed perpendicular to ground, both sides are parallel to horizontal plane and ensure plane target drone and circle target up and down
In steel end face is generally aligned in the same plane, the optical center of camera places and ensures the position of camera position and plane target drone perpendicular to target face
It sets and immobilizes;
2)The central point for defining plane target drone upper left corner dot is the origin of world coordinates, and world coordinatesZFace is flat
On the target of face,ZAxis is perpendicular to the center of circle of upper left corner dot;
3)Target image is acquired, the pixel coordinate in the center of circle of all characteristic points is obtained through image procossing(x i ,y i );
4)Because plane target drone be precision instrument, target up and down adjacent two characteristic point absolute position it is known that
Therefore can obtain corresponding to each target characteristic point world coordinates (X wi ,Yw i );
5)When obtain round steel end face center point pixel coordinate (x,y) after, according to above-mentioned pixel coordinate obtained by calibrating and
The transformational relation of world coordinates, you can acquire corresponding round steel end face center point world coordinates (X W ,Y W )。
Centroid method seeks the image coordinates value of characteristic point:
The most important pixel coordinate and world coordinates value for being to determine each target dot center point of target during this.Characteristic point
The acquisition of pixel coordinate:Using the area etc. for removing irrelevant region, finally Gauss weighted mass center method is used to obtain target feature
The position of point.It extracts on target after the image coordinates of all characteristic points, it is known that the world coordinates of each characteristic point and each round steel
The image coordinates of end face center point can be obtained round steel end face with Delaunay subdivision triangular interpolation value camera calibration methods
The world coordinates of central point.
When using Delaunay subdivision triangular interpolation value camera calibration methods, it is desirable that the pixel coordinate of the characteristic point of target
Value and world coordinates value are one-to-one relationships, however it is by row to apply the pixel coordinate of the target characteristic point of centroid method acquisition
Arrangement, however the coordinate of each row is random, therefore uses data processing method, make the pixel coordinate of characteristic point by
It shows small to big arrangement.
The acquisition of characteristic point world coordinates value:
Scaling board up and down adjacent two characteristic point absolute position it is known that set target parameters line number asm;Columns isn;Row
Spacing isd m ;Column pitch isd n .World coordinates corresponding to the characteristic point center of circle(X wi ,Y wi ).
Many triangles will be formed after characteristic point triangulation, round steel end face center point pixel coordinate is included in composition
Triangle in.It can be acquired by the image coordinate value of the correspondence and target point of characteristic point world coordinates and image coordinate
World coordinates value.
4, Image Acquisition, image enhancement processing and image binaryzation is carried out respectively to main phase machine and auxiliary camera to handle
Vision system carries out Image Acquisition respectively to main phase machine and auxiliary camera first, obtains the original graph of bundled round steel end face
Picture.
Image enhancement enhances method using greyscale transformation, and stereo pairs increasing is carried out using function imadjust in MATLAB
By force, the tonal range to be converted can be automatically obtained by function stretchlim in original image in the function, can also be used solid
Definite value can make system running speed faster in the case where image capture environment is constant using fixed value, and this system is using solid
Definite value, it is verified [0.5;It is optimal when 1].Tonal range after image transformation uses as default i.e. 0-255.
Image binaryzation be in MATLAB by im2bw functions by greyscale image transitions be bianry image, using
Threshold parameter must be set first when im2bw functions, threshold value can be obtained automatically by graythresh functions, can also be used
Fixed threshold.Since this system image zooming-out carries out under light conditions, the image stabilization of acquisition, not using fixed threshold
Picture quality can be only improved, but also system running speed can be improved, therefore this system uses fixed threshold, verified threshold
Value is optimal when being 0.6.
5, image is carried out respectively to main phase machine and auxiliary camera and carries out round identification, centralized positioning
Hough transform is to identify one of the basic skills of geometry, the function in MATLAB in image procossing
Imfindcircles is exactly to carry out round identification with Hough transform.It need to be determined when imfindcircles function uses several
A parameter:First, round radius need to be detected, the radius of verified this system is set as [50 90] and is preferred;Two for and
Other background is divided into ' bright ' and ' dark ', this system to be set as ' bright ';Three be parameter ' Sensitivity ' spirit
Sensitivity, the range of sensitivity is between [0,1], and sensitivity is bigger, and the circle that can be detected is more, then the risk of error detection is also therewith
Increase, it is that effect is preferable that verified sensitivity, which is 0.95,;The last one parameter is ' EdgeThreshold ' edge gradient threshold,
Its range is between [0,1], and the smaller circle that can be detected of edge gradient threshold is more, and error detection is also bigger therewith, works as edge
Effect is best when Grads threshold is 0.7.
The circle fitted in round identify is counted, the sum for recording the circle fitted is the root of round steel
Number.Comprising all circular centre coordinates for fitting and in the return value centers of function imfindcircles, utilize
Size functions can read round number included in centers, this numerical value is the quantity of round steel, and record number is to reach
To the function of counting.
6, the online radical and diameter information for reading bundled round steel in company information library in real time
Corporate intranet is connected by the computer of system, the online production information read in real time in company information library is most closed
Key be current bundled round steel radical and diameter information.Wherein, the total weight of bundled round steel be actually weigh to obtain, single circle
The weight of steel is calculated by material, diameter and length information, and the radical of bundled round steel is the total weight with bundled round steel
Divided by the estimation result that the theoretical calculation weight of single round steel obtains, there may be 1-2 for the spillikin of different size
The error of root.
7, comprehensive descision is carried out to the round steel end face center point that main phase machine and auxiliary camera obtain according to the diameter information of round steel,
It determines the radical and reliability that bundled round steel visual identity goes out and carries out central point distance verification
The image recognition result of 1 main phase machine and 3 auxiliary cameras can be obtained by the image recognition operations of abovementioned steps.
Wherein, the axis at the center of the bundled round steel of main phase machine face, 3 auxiliary cameras and bundled round steel is a certain included angle, that is to say, that 4
A camera has respectively obtained the image of the bundled round steel end face of different visual angles and has been identified and positioned.If all visual angles are all
It does not block, then all round steel can be identified and be positioned, and the end face center point of these round steel should be with uniformity.If
Some visual angle, which exists, blocks, then None- identified and the round steel blocked is located on the image.Show Ge Gexiang by test of many times
Machine is less than 0.6mm, root of this precision for determining round steel using the error range of aforementioned image recognition and location of the core method
Number is enough.According to the diameter information of round steel, it can be determined which point is corresponding same root round steel, and can also judge recognition result can
By property.
Such as:The specification of online bundled round steel is diameter 20mm, if 4 that 1 main phase machine and 3 auxiliary cameras identify
Central point is gathered in the circle of a small diameter(Some value more than 0.6mm and much smaller than round steel diameter can be set, generally
The 10% of diameter is could be provided as, is exactly 2mm here), it may be considered that the central point of corresponding same root round steel, identifies at this time
Reliability is highest, can be set to 1.If there is the central point of 3 cameras identification is gathered in the circle of a small diameter, then may be used
To think that the central point of corresponding same root round steel, the reliability identified at this time are time height, 0.8 can be set to.And so on, it obtains
The radical and reliability of the round steel of identification.
The central point out of all 4 cameras identifications is weighted summation and obtains the comprehensive identification of all round steel central points
Coordinate seeks distance two-by-two to all synthesis coordinate identifications, and all distance values should be more than round steel diameter, if meeting
Pass through verification.In view of the site error of identification, all distance values are all higher than the 90% of diameter(Here it is exactly 18mm), also have
Standby higher reliability, can pass through verification.If all distance values have 90% less than diameter(Here it is exactly 18mm)'s
Situation, then relevant two central points may be wrong.
8, the result of calculation in the visual identity result and company information library of more bundled round steel radical, comprehensive descision
The actual test operating condition in conjunction with production scene is needed specifically to classify when comprehensive descision, it was therefore concluded that, such as:
(1)Central point distance verification is passed through, identification radical is consistent with the radical in company information library, then identification is correct;
(2)In all central point identification certainties there are reliability be 0.2 the case where, not by central point apart from school
It tests, identifies that the radical in radical and company information library is inconsistent, then identify mistake, be subject to company information library;
(3)The case where there are reliability is 0.2 in all central point identification certainties has passed through central point apart from school
Test, identify that the radical in radical and company information library is inconsistent, then recognition result must by manpower intervention, correct recognition result or
The radical information in company information library.
Claims (1)
1. bundled round steel multi-vision visual identifying system is used for the identification and counting of bundled round steel end face, the system comprises:Light source
(1), main phase machine(2), main phase machine and light source bracket(3), auxiliary camera(4), auxiliary camera support(5), computer(6)And scaling board
(7), which is characterized in that light source(1)For annular light source, main phase machine(2)In annular light source(1)Looping pit in and light source(1)Together
Axis arrangement, light source(1)With main phase machine(2)Pass through main phase machine and light source bracket(3)It installs and fixes, auxiliary camera(4)Pass through auxiliary phase
Machine support(5)It installs and fixes, multiple auxiliary cameras(4)And camera support(5)Around main phase machine(2)Axis radial equipartition,
Main phase machine(2)With multiple auxiliary cameras(4)Multi-vision visual image collecting device is formed, when installation, passes through and adjusts main phase machine and light source
Holder(3)Make light source(1)With main phase machine(2)Axis perpendicular to the center of the end face of bundled round steel, it is multiple by adjusting
Auxiliary camera support(5)Make multiple auxiliary cameras(4)Axis and main phase machine(2)Axis intersect at a point, and the focus is made to be located at
The theoretical center position of bundled round steel entirety end face, light source(1), main phase machine(2), multiple auxiliary cameras(4)And computer(6)Pass through
Cable connects, scaling board(7)For main phase machine(2)With multiple auxiliary cameras(4)Vision calibration.
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN108507484A (en) * | 2018-04-08 | 2018-09-07 | 河北科技大学 | Bundled round steel multi-vision visual identifying system and method for counting |
CN112037195A (en) * | 2020-08-31 | 2020-12-04 | 中冶赛迪重庆信息技术有限公司 | Method, system, equipment and medium for detecting abnormal length of bar |
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2018
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Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN108507484A (en) * | 2018-04-08 | 2018-09-07 | 河北科技大学 | Bundled round steel multi-vision visual identifying system and method for counting |
CN108507484B (en) * | 2018-04-08 | 2019-09-24 | 河北科技大学 | Bundled round steel multi-vision visual identifying system and method for counting |
CN112037195A (en) * | 2020-08-31 | 2020-12-04 | 中冶赛迪重庆信息技术有限公司 | Method, system, equipment and medium for detecting abnormal length of bar |
CN112037195B (en) * | 2020-08-31 | 2023-04-07 | 中冶赛迪信息技术(重庆)有限公司 | Method, system, equipment and medium for detecting abnormal length of bar |
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