CN109341590A - Projection detection and self-roundness regulation device for shape deviation of shell ring - Google Patents
Projection detection and self-roundness regulation device for shape deviation of shell ring Download PDFInfo
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- CN109341590A CN109341590A CN201811316184.7A CN201811316184A CN109341590A CN 109341590 A CN109341590 A CN 109341590A CN 201811316184 A CN201811316184 A CN 201811316184A CN 109341590 A CN109341590 A CN 109341590A
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- 238000001514 detection method Methods 0.000 title claims abstract description 19
- 238000012545 processing Methods 0.000 claims abstract description 8
- 238000005259 measurement Methods 0.000 claims description 24
- 230000001105 regulatory effect Effects 0.000 claims description 15
- 230000003287 optical effect Effects 0.000 claims description 7
- 238000000034 method Methods 0.000 description 11
- 238000012360 testing method Methods 0.000 description 10
- 229910000831 Steel Inorganic materials 0.000 description 4
- 230000008901 benefit Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 239000010959 steel Substances 0.000 description 4
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Classifications
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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
- G01B11/24—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
- G01B11/25—Measuring 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
- G01B11/2518—Projection by scanning of the object
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- Length Measuring Devices By Optical Means (AREA)
Abstract
The invention provides a projection detection and self-roundness regulation device for the shape deviation of a shell ring, which comprises: the device comprises a projection grid line (1), a measured cylindrical section (2), a CCD camera (3) and a computer (4), wherein the projection grid line (1) transmits emitted equidistant gratings on a screen projected by the measured cylindrical section (2), the grid line spacing formed on the surface of the measured cylindrical section (2) is changed into unequal deformed grid lines, the CCD camera (3) shoots the deformed grid lines and transmits an image to the computer (4), the density change of the deformed grid lines and the frequency of each point of the deformed grid lines are related to the height of the measured cylindrical section (2), the computer (4) decodes through fast Fourier change to output a frequency phase value and digital image gray scale information, and an accurate shell size can be obtained through data processing, therefore, the full-field phase can be quickly analyzed, the shape and position result can be quickly displayed, the shape deviation of the shell ring can be obtained, the computer (4) is connected with the controller, and the roundness of the measured shell ring (2) can be adjusted according to the shape deviation of the shell ring.
Description
Technical field
The present invention relates to morpheme fields of measurement, a kind of shell ring form variations projection detection and self-regulated circularity are especially related to
Device.
Background technique
The detection of Moire morpheme is the simple and practical measuring technique of one kind of the development seventies, is measured using contour map
Extremely complex three-dimensional body, relatively common is projection moire method, with projector by optical grating projection on a surface of an, then benefit
The moire pattern of overlapping master grating is shot with camera.The principle that moire generates is that the geometry proof with deformation gate away from variation obtains
?.The eighties carrier wave and phase measurement, by directly recording grating projected image, to measure display moire pattern
Position phase whole audience value, and then the 3D rendering of object is shown automatically.However these methods do not generate moire pattern obtain as a result, and
In Large Structures Shape, especially shell ring form variations projection detection and the application of self-regulated circularity, the side of the sixties is often continued to use
Method is not detected using computer automatically, and coarser scale is poor.
With the development of optics and computer technology, detect automatically in non-contact behavior has new intention, projected light in the recent period
The method of grid is to prolong the principle for drawing projection moire, then with shift difference position phase method and individual figure frequency analysis FFT method, so
And optical measurement mechanics principle combination computer image processing technology is not fully utilized in this method yet, only rests on theory stage.
Summary of the invention
Inventive concept of the invention is to provide a kind of shell ring form variations projection detection and self-regulated roundness device, uses throwing
Shadow grating, according to the morpheme on the automatic detection object surface of the principle, projection grating forms grid line image, automatic shape in surface of shell
At frequency coding, the digital picture of profilome try is collected using CCD camera, pass through quick Fourier using computer system
Leaf variation decoding, output frequency position is mutually worth and digital image gray level information, and accurate shell scale can be obtained through data processing,
So as to fast resolving whole audience position phase, quickly show morpheme as a result, realizing computational intelligence.
For this purpose, the purpose of the present invention is to provide a kind of shell ring form variations projection detection and self-regulated roundness devices, comprising:
Projecting grating (1) is tested shell ring (2), CCD camera (3) and computer (4), and the projecting grating (1) will be between the grade of sending
Away from grating through on the screen of tested shell ring (2) projection, tested shell ring (2) surface forms raster image, and grid
Line spacing becomes not equal deformation grid line, the CCD camera (3) and shoots the deformation grid line, send image to the calculating
Each dot frequency of machine (4), the deformation moire grids density variation and deformation grid line is related with the height of the tested shell ring (2), will
The relationship is decoded by the computer (4) by fast Fourier transform, and output frequency position is mutually worth and digital image gray level
Accurate shell scale can be obtained through data processing in information, so as to fast resolving whole audience position phase, quickly shows morpheme knot
Fruit, to obtain the shell ring form variations, the computer (4) connects controller, and the controller is according to the shell ring shape
The circularity of shell ring (2) is tested described in shape deviation adjusting.
Preferably, the projecting grating (1) includes projector.
Preferably, raster image 0-0 light intensity mechanical periodicity on the screen, frequency f0 are placed before the screen tested
Just there is a raster image on shell ring (2), surface, and grating spacing becomes deformation grid line not etc..At off screen curtain h, straight line A-A is parallel
It is f1 in the frequency on 0-0, line A-A, identical in the grid line number that 0-0 and A-A intersects, length is different, frequency shift, and: f1-f0
=S*h=h/k, wherein S and k is constant, therefore: h=k* (f1-f0), the frequency of each point on object is obtained, each point is found
Difference on the frequency, the distance h to frame out is calculated by formula (1), with frequency measurement scale, is directly collected using CCD camera 3
The digital picture of frequency coding, to obtain the information of contour h, i.e. the information of equipotential phase.
Preferably, the CCD camera (3) is paraxonic CCD camera, internal projector and CCD camera (3) optical axis
Between there are angles.
It preferably, include image level there are measurement error caused by angle between projector and CCD camera (3) optical axis
Size shortens and horizontal symmetrical shape, and phase fringes have obvious asymmetric as a result, the position proportional to symmetry axis x is mutually worth,
That is △=△m+△r, such as symmetric points A, B two o'clock respective phase is ΦA, ΦB, then △ m=ΦA/2+ΦB/ 2, △ r=(ΦA/2-
ΦB/ 2) * x/L, wherein L is A, the distance between B half.
Finishing steel cylindrical shell with Φ 130 is that example is tested, while being calculated theoretical carrier wave figure and being carried out each step point
Analysis is compared, to obtain phase package figure and theoretical curve, is finally converted into circularity Ri, Ri=(I by height h (x) value2 i+W2 i)1/2,
In formula, i is the point of required arbitrary point, to obtain the circularity radius value at the corresponding height of surface, data are printed in list, from
And the relative error of each point is calculated, in range of the error more than circularity permission, the present embodiment, relative error threshold value is set as
One thousandth centimetre, therefore data testing accuracy is high, considerably beyond the requirement of engineering.Due to the limitation at visual angle, circularity tests edge
Section is divided into four regions, and cylinder is placed on turntable, is often rotated by 90 ° measurement once, corotating four times, acquires four
Grid line striograph can measure the circularity of 360 degree of interior profile each points, and the following table 1 indicates the comparison sheet of circularity test and notional result,
Unit is pixel.
The comparison sheet of 1 circularity of table test and notional result
Unit: pixel
| Point | Test result | Calculated value | Error |
| 1 | 282.134910 | 282.842713 | -0.250246 |
| 2 | 282.466210 | 282.842713 | -0.133114 |
| 3 | 282.402597 | 282.842713 | -0.155569 |
| 4 | 282.646210 | 282.842713 | -0.059474 |
| 5 | 282.135505 | 282.842713 | -0.249682 |
Beneficial effects of the present invention:
Using new shaped position automatic measurement computer processing system and method, the radius number of circumference arbitrary point is measured
Value finishes steel cylindrical shell surface shape in measurement Φ 130 to obtain the circularity contour line picture of 360 degrees omnidirection
It succeeds in the measurement of position, same principle can be generalized to along the measurement of cylindrical shell axis direction surface morpheme, give full play to
The advantages of computer Quick Acquisition and operation, while the measurement of general object can also be spreaded to, it is convenient according to image-forming principle
The morpheme measurement of large scale object is solved, and carries out the adjustment of circularity with hop controller.
According to the following detailed description of specific embodiments of the present invention in conjunction with the accompanying drawings, those skilled in the art will be brighter
The above and other objects, advantages and features of the present invention.
Detailed description of the invention
Some specific embodiments of the present invention is described in detail by way of example and not limitation with reference to the accompanying drawings hereinafter.
Identical appended drawing reference denotes same or similar part or part in attached drawing.It should be appreciated by those skilled in the art that these
What attached drawing was not necessarily drawn to scale.Target and feature of the invention will be apparent from view of following description taken together with the accompanying drawings,
In attached drawing:
Attached drawing 1 is to project detection and self-regulated roundness device structural representation according to the shell ring form variations of the embodiment of the present invention
Figure；
Attached drawing 2 is to project detection and self-regulated roundness device measuring principle in shell ring form variations according to the embodiment of the present invention
Schematic diagram；
Attached drawing 3 is the Refining phase schematic diagram according to the embodiment of the present invention；
Attached drawing 4 is to correct schematic diagram according to the circularity of the embodiment of the present invention.
Specific embodiment
Detection and self-regulated roundness device structural schematic diagram, the projection of shell ring form variations are projected referring to Fig. 1 shell ring form variations
Detection and self-regulated roundness device, comprising: projecting grating 1 is tested shell ring 2, CCD camera 3 and computer 4, and projecting grating 1 wraps
Projector is included, by the equidistant grating of sending through being tested on the screen that shell ring 2 projects, tested 2 surface of shell ring is formed projector
Raster image, and grating spacing becomes deformation grid line not etc., and CCD camera 3 shoots the deformation grid line, image is sent to
Each dot frequency of computer 4, the variation of deformation moire grids density and deformation grid line is related with the height of tested shell ring 2, which is led to
It crosses computer 4 to decode by fast Fourier transform, output frequency position is mutually worth and digital image gray level information, through data processing
Accurate shell scale can be obtained, so as to fast resolving whole audience position phase, quickly show morpheme as a result, to obtain shell ring shape
Shape deviation, computer 4 connect controller, and controller adjusts the circularity of tested shell ring 2 according to shell ring form variations.
Referring to fig. 2, the straightline propagation and projection imaging of light are the bases of projection detection and self-regulated circularity, will be equidistant
Projecting grating 1 projects on screen, and blur-free imaging of focusing is as shown in Fig. 2, raster image 0-0 light intensity mechanical periodicity on screen,
Frequency is f0.Place tested shell ring before screen, just there is a raster image on surface, and grating spacing becomes deformation grid line not etc..?
At off screen curtain h, if straight line A-A is parallel to 0-0, due to light straightline propagation, the frequency on line A-A is f1.In 0-0 and A-A phase
The grid line number of friendship is identical, and length is different, frequency shift, and: f1-f0=S*h=h/k, wherein S and k is constant, therefore: h
=k* (f1-f0) (1).
If the frequency of each point on object can be obtained, the difference on the frequency of each point is found, can be calculated and be frameed out by formula (1)
Distance h, with frequency measurement scale.It is therefore contemplated that highly linear is encoded among frequency by moire grids density variation, this
It is exactly morpheme frequency coding principle, the digital picture of frequency coding is directly collected using CCD camera 3, so that it may obtain
The information of high line h, the i.e. information of equipotential phase.
Referring to Fig. 3-4, in the present embodiment, CCD camera (3) is paraxonic CCD camera, and internal projector and CCD take the photograph
There are angle between 3 optical axis of camera, measurement error includes the shortening of image level size and horizontal symmetrical shape, phase fringes
With it is obvious asymmetric as a result, and from the point of view of frequency coding angle, since strabismus horizontal size shortens, frequency increases, and base plane is flat
It moves, meanwhile, strabismus has rotated base plane, therefore generates the increase and decrease position proportional to symmetry axis x and be mutually worth.That is △=△m+△r, such as
Symmetric points A known to fruit, B two o'clock, respective phase ΦA, ΦB, then △ m=ΦA/2+ΦB/ 2, △r=(ΦA/2-ΦB/2)*
x/L.Wherein L is A, the distance between B half.
Finishing steel cylindrical shell with Φ 130 is that example is tested, while being calculated theoretical carrier wave figure and being carried out each step point
Analysis is compared, to obtain phase package figure and theoretical curve, is finally converted into circularity Ri, Ri=(I by height h (x) value2 i+W2 i)1/2,
In formula, i is the point of required arbitrary point, to obtain the circularity radius value at the corresponding height of surface, data are printed in list, from
And the relative error of each point is calculated, in range of the error more than circularity permission, the present embodiment, relative error threshold value is set as
One thousandth centimetre, therefore data testing accuracy is high, considerably beyond the requirement of engineering.Due to the limitation at visual angle, circularity tests edge
Section is divided into four regions, and cylinder is placed on turntable, is often rotated by 90 ° measurement once, corotating four times, acquires four
Grid line striograph can measure the circularity of 360 degree of interior profile each points, and the following table 1 indicates the comparison sheet of circularity test and notional result,
Unit is pixel.
The comparison sheet of 1 circularity of table test and notional result
Unit: pixel
| Point | Test result | Calculated value | Error |
| 1 | 282.134910 | 282.842713 | -0.250246 |
| 2 | 282.466210 | 282.842713 | -0.133114 |
| 3 | 282.402597 | 282.842713 | -0.155569 |
| 4 | 282.646210 | 282.842713 | -0.059474 |
| 5 | 282.135505 | 282.842713 | -0.249682 |
The present embodiment uses new shaped position automatic measurement computer processing system and method, measurement circumference arbitrary point
Radius distance value finishes steel cylindrical shell in measurement Φ 130 to obtain the circularity contour line picture of 360 degrees omnidirection
It succeeds in the measurement of surface morpheme, same principle can be generalized to along the measurement of cylindrical shell axis direction surface morpheme, sufficiently
The advantages of having played computer Quick Acquisition and operation, while the measurement of general object can also be spreaded to, according to image-forming principle
The convenient morpheme measurement for solving large scale object, and the adjustment with hop controller progress circularity.
Although the present invention is described by reference to specific illustrative embodiments, these embodiments are not will receive
Restriction and only limited by accessory claim.It should be understood by those skilled in the art that can be without departing from of the invention
Change and modification are able to carry out to the embodiment of the present invention in the case where protection scope and spirit.
Claims (5)
1. a kind of shell ring form variations projection detection and self-regulated roundness device, characterized by comprising: projecting grating (1) is tested
The equidistant grating of sending is penetrated the quilt by shell ring (2), CCD camera (3) and computer (4), the projecting grating (1)
It surveys on the screen of shell ring (2) projection, tested shell ring (2) surface forms raster image, and grating spacing does not become not etc.
Grid line is deformed, the CCD camera (3) shoots the deformation grid line, sends image to the computer (4), the deformation gate
Each dot frequency of line density variation and deformation grid line is related with the height of the tested shell ring (2), which is passed through the meter
Calculation machine (4) is decoded by fast Fourier transform, and output frequency position is mutually worth and digital image gray level information, can through data processing
Accurate shell scale is obtained, so as to fast resolving whole audience position phase, quickly shows morpheme as a result, to obtain the shell ring
Form variations, the computer (4) connect controller, and the controller adjusts the tested cylinder according to the shell ring form variations
Save the circularity of (2).
2. a kind of shell ring form variations projection detection according to claim 1 and self-regulated roundness device, it is characterised in that: institute
Stating projecting grating (1) includes projector.
3. a kind of shell ring form variations projection detection according to claim 1 and self-regulated roundness device, it is characterised in that: institute
State raster image 0-0 light intensity mechanical periodicity on screen, frequency f0 places tested shell ring (2) before the screen, and just there is light on surface
Grid image, and grating spacing becomes deformation grid line not etc..At off screen curtain h, straight line A-A is parallel to 0-0, the frequency on line A-A
Rate is f1, identical in the grid line number that 0-0 and A-A intersects, and length is different, frequency shift, and: f1-f0=S*h=h/k, wherein S
It is constant with k, therefore: h=k* (f1-f0) obtains the frequency of each point on object, finds the difference on the frequency of each point, is counted by formula (1)
It calculates the distance h to frame out and the digitized map of frequency coding is collected directly using CCD camera 3 with frequency measurement scale
Picture, to obtain the information of contour h, i.e. the information of equipotential phase.
4. a kind of shell ring form variations projection detection according to claim 1 and self-regulated roundness device, it is characterised in that: institute
Stating CCD camera (3) is paraxonic CCD camera, and there are angles between internal projector and CCD camera (3) optical axis.
5. a kind of shell ring form variations projection detection according to claim 4 and self-regulated roundness device, it is characterised in that: throw
It there are measurement error caused by angle include that image level size shortens and horizontal between shadow device and CCD camera (3) optical axis
Symmetric shape, phase fringes have obvious asymmetric as a result, the position proportional to symmetry axis x is mutually worth, i.e. △=△ m+ △ r, such as
Symmetric points A, B two o'clock respective phase is Φ A, Φ B, then △ m=Φ A/2+ Φ B/2, △ r=(Φ A/2- Φ B/2) * x/L, wherein
L is A, the distance between B half.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111238402A (en) * | 2019-02-21 | 2020-06-05 | 惠州市微米立科技有限公司 | Shell detection method based on structured light three-dimensional imaging |
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| CN1059791A (en) * | 1990-09-13 | 1992-03-25 | 清华大学 | A kind of optical means and device that does not have the measurement 3D shape of reference planes |
| DE10355010A1 (en) * | 2003-11-25 | 2005-06-23 | Waliczek, Peter | Measurement device for measuring surfaces of three-dimensional objects has strip projector with several sections of line structures or sine waves applied to rotating cylinder, projected onto measurement body, recorded by one or more cameras |
| CN204902768U (en) * | 2015-05-29 | 2015-12-23 | 南京南车浦镇城轨车辆有限责任公司 | Rail vehicle tolerance size measurement system |
| CN106017358A (en) * | 2016-08-10 | 2016-10-12 | 边心田 | Three-dimensional surface shape measurement method based on precorrected grating projection |
| CN106289109A (en) * | 2016-10-26 | 2017-01-04 | 长安大学 | A kind of three-dimensional reconstruction system based on structure light and method |
-
2018
- 2018-11-07 CN CN201811316184.7A patent/CN109341590B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1059791A (en) * | 1990-09-13 | 1992-03-25 | 清华大学 | A kind of optical means and device that does not have the measurement 3D shape of reference planes |
| DE10355010A1 (en) * | 2003-11-25 | 2005-06-23 | Waliczek, Peter | Measurement device for measuring surfaces of three-dimensional objects has strip projector with several sections of line structures or sine waves applied to rotating cylinder, projected onto measurement body, recorded by one or more cameras |
| CN204902768U (en) * | 2015-05-29 | 2015-12-23 | 南京南车浦镇城轨车辆有限责任公司 | Rail vehicle tolerance size measurement system |
| CN106017358A (en) * | 2016-08-10 | 2016-10-12 | 边心田 | Three-dimensional surface shape measurement method based on precorrected grating projection |
| CN106289109A (en) * | 2016-10-26 | 2017-01-04 | 长安大学 | A kind of three-dimensional reconstruction system based on structure light and method |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN111238402A (en) * | 2019-02-21 | 2020-06-05 | 惠州市微米立科技有限公司 | Shell detection method based on structured light three-dimensional imaging |
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