CN207319046U - A kind of laser is in machine centering and inter process measuring device - Google Patents
A kind of laser is in machine centering and inter process measuring device Download PDFInfo
- Publication number
- CN207319046U CN207319046U CN201720589674.9U CN201720589674U CN207319046U CN 207319046 U CN207319046 U CN 207319046U CN 201720589674 U CN201720589674 U CN 201720589674U CN 207319046 U CN207319046 U CN 207319046U
- Authority
- CN
- China
- Prior art keywords
- laser
- workpiece
- gauge head
- centering
- coordinate system
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Abstract
The utility model discloses a kind of laser in machine centering and inter process measuring device, is made of laser feeler and host computer, includes smart camera, MEMS scanning galvanometer projection arrangements, WIFI module, lithium battery and LED annular light sources in gauge head.Smart camera and MEMS scanning galvanometers projection arrangement composition single camera vision system, can carry out three-dimensional reconstruction, and a gauge head can complete laser centering and online inter process measurement function.The present apparatus goes out the three-dimensional coordinate of feature on workpiece using laser three-D reconstruction principle rapid extraction, and the position orientation relation of gauge head coordinate system and lathe coordinate system is obtained by demarcating, these data real-time radios are transferred to host computer, workpiece coordinate system is established by host computer automatically and quick and precisely detects part morpheme size, is measured so as to fulfill the centering and inter process of workpiece.
Description
Technical field
The utility model belongs to optical three-dimensional measurement and numerical control manufacture field, is realized using laser MEMS three-dimensional reconstructions
Centering and inter process measurement to workpiece, can replace traditional contact measurement method, and have faster speed.
Background technology
In digital control processing field, five-shaft linkage numerical control machining center is since its high accuracy, efficient feature are in modern work
Occupy critical role in industry.5-shaft linkage numerical control processing also develops while developing to high accuracy towards high Composite direction,
Processing is combined as a whole with measurement, and in-process measurement replaces in order, and it is that production is made at this stage to ensure machining accuracy under monitors environment
The main flow direction made.
Measurement for workpiece in NC Machining Process mainly has workpiece centering, inter process measurement two large divisions.Workpiece
Centering mainly positions to workpiece and establishes workpiece coordinate system, makes it consistent with default coordinate system in processing program, this is
The basis that workpiece can be processed accurately；Inter process measurement is referred to after one of manufacturing procedure is completed, and workpiece is referred to according to technology
Mark requirement is detected, and checks whether qualification to confirm next step fabrication plan.Surveyed at present for workpiece centering and inter process
Amount mainly has three kinds of methods：
(1) manual centering and measurement
Manual method is to carry out centering and detection to workpiece using general measure instruments such as micrometer, centering block, vernier calipers.
Such a method inefficiency, and influenced be subject to human factor very big, detection process is cumbersome and time consuming, can not also ensure essence
Degree, seriously affects production and the processing quality of product, the method only uses on some low side lathes at present, and is phased out
Trend.
(2) online touch trigger probe centering and detection
Touch trigger probe is loaded onto in the tool magazine of numerical control machining center, gauge head occupies a special cutter number, it need not
The rotation of main shaft.When needing detection, it is detected after gauge head is replaced in tool magazine according to corresponding detection program, gauge head can be used
Carry out workpiece centering and inter process measurement.The technology well combines process with detection process, has in processing
There is clear superiority in terms of the product of complex space curved surfaces, its free degree is big, avoids to workpiece multiple clamping, shortens manufacture week
Phase, reduces production cost, and accurate guidance can be given to process, so in compressor, the blade, whole of turbine combustion engine
Body impeller and propeller etc. are this kind of complicated and are to be had a wide range of applications in the processing of the part of space curved surface, are current height
The on-line checking means of mainstream on end machining tool.
3) off-line measurement
Offline inspection refers exclusively to inter process measurement.Offline inspection refers between the process of machine tooling and machines it
Afterwards, object is removed from lathe, recycles other detection devices such as three coordinate measuring machine to be detected processing object.It is this
Testing equipment is bulky, expensive, rigorous service condition, and detection process is cumbersome time-consuming and laborious, and cannot be existing in processing
Field uses, and is only used for offline sampling check for quality, and the backward artificial detection pattern of tradition is still used in processing site.For one
A little large complicated long period processing components, once finding that quality is not inconsistent standardization and must be returned during offline inspection
Repair, rework process is not only complicated, cumbersome, time-consuming, laborious but also can be due to being not allowed to cause to add by positioning during reprocessing
Error.
Above-mentioned all methods inherently belong to contact type measurement, and unless provided with touch trigger probe, otherwise can not be real
Existing on-line measurement.Therefore the utility model proposes a kind of online laser detector, the complete of laser three-D reconstruction technique is passed through
Centering and inter process into workpiece measure, and on the premise of requirement on machining accuracy is met, have than contact triggering gauge head faster
Speed.
Utility model content：
The utility model proposes a kind of laser in machine fast aligning and to detect gauge head, can realize work on numerical control machine tool
Quick establish of part coordinate system belongs to non-contact measurement with inter process measurement, this method, traditional contact can be replaced to survey
Head realizes the centering of workpiece, and as general NC cutter, and gauge head is placed into tool magazine by off working state, and when work takes
Go out to be installed in lathe end clamp.It is fast with speed, the characteristics of precision is high.
The technical solution that the utility model is taken is：A kind of laser fast calibrating device, including one be used for generate 3D points
The smart camera of cloud data, the projection arrangement of a projective structure light, WIFI module, light compensating lamp, power supply etc..
The smart camera is made of general industry camera and embedded system, and wherein embedded system is grasped by linux
Make system and ARM chips composition, be integrated with image processing algorithm and 3D algorithm for reconstructing in system, can be to the picture of shooting in phase
Calculated in machine, directly export 3D point cloud data.
The utility model proposes gauge head have the function of that centering and inter process measure two kinds, both function basic principle phases
Together, it is all based on laser three-D and rebuilds the three-dimensional data that principle reconstructs workpiece features, these three-dimensional datas contains workpiece institute
Detect all information of feature, therefore the three-dimensional data of these features calculated, can realize workpiece survey centering and
Measurement.
Comprise the following steps that：
The first step：Calibration
, it is necessary to be demarcated before the work of centering gauge head, that is, need to obtain between gauge head coordinate system and lathe coordinate system
Position orientation relation.This programme uses the method that gauge head and lathe coordinate system transition matrix M are solved based on standard ball surface point cloud.
Second step：Rebuild for the laser three-D of workpiece features
For centering and both functions are measured, the step of it is rebuild is different, is described as follows respectively：
(1) three-dimensional reconstruction of centering function
Before three-dimensional reconstruction is carried out to the feature of workpiece, first according to needed for the characteristics of workpiece determines to establish workpiece coordinate system
The element wanted, these elements, which add up, to be had to include six points, can be summarized as more i.e. (circle), a line (2 points), simultaneously
(3 points).Gauge head is moved to above these elements, shooting image, and extracts the effective coverage on image.These effective districts
Domain refers to that the needs on workpiece are used for establishing the characteristic element of coordinate system, such as point (circle), line, face etc..Therefore when 3D is rebuild
Effective image area part only need to be calculated, it is possible to reduce unnecessary calculation amount, and the more three-dimensional extraction speed of two dimensional image feature
Degree is fast.
After extracting effective coverage, gauge head proceeds by reconstruction, and the MEMS galvanometers projection arrangement of gauge head projects more main feed lines
Laser picture is to the picture that on measured workpiece, each frame projection arrangement of smart camera sync pulse jamming is projected.Obtained according to shooting
Workpiece picture with line laser and the monocular camera system demarcated, can be according to the principle of binocular stereo vision to work
Effective coverage in part picture carries out three-dimensional reconstruction, and the effective coverage of workpiece picture is with rebuilding the effective coverage obtained before here
It is identical.Algorithm for reconstructing has been implanted in the embedded system of smart camera, and the three-dimensional data whole WIFI rebuild is wireless
It is transferred in host computer, centering calculating is carried out in host computer.
(2) three-dimensional reconstruction of inter process measurement function
Inter process measurement needs the feature that detects varied, but these features are substantially by point (circle), line, face this
Three kinds of element compositions.Therefore only need to decompose some feature to be detected, be broken down into simple point (circle), line,
Then these basic elements are carried out three-dimensional reconstruction by face respectively.Method for reconstructing is identical with method for reconstructing during centering, i.e., only
Effective coverage is extracted and is rebuild.Algorithm for reconstructing has been implanted in the embedded system of smart camera, is rebuild
Three-dimensional data whole WIFI is wirelessly transmitted in host computer, and centering calculating is carried out in host computer.
3rd step：Carry out centering and the inter process measurement of workpiece
(1) centering
This programme uses 6 method for centering, i.e., establishes workpiece at 2 points at 3 points by a point, a line (), a plane ()
Coordinate system., can be by all three-dimensional data conversions for reconstructing and in host computer first according to first step data obtained by calibrating
To under lathe coordinate system.Under lathe coordinate system, by the circle (point) of acquisition, line, face three-dimensional data is intended with least square method
Close, justified respectively (point), line, the mathematic(al) representation in face, the projective representation of its midpoint in the plane is the original of workpiece coordinate system
Point, the direction of the projective representation's workpiece coordinate system Y-axis of straight line in the plane, the normal vector in face represent the side of workpiece coordinate system Z axis
To X-direction can determine whether according to right hand method, can so complete the centering of workpiece.
(2) inter process measures
These three-dimensional datas are handled in host computer.All three-dimensional datas are demarcated according to the first step first
To data be transformed under lathe coordinate system, carry out data fitting to it using least square method afterwards, including inside and outside circle, inside and outside
Ellipse fitting, fitting a straight line, plane, surface fitting.After the completion of fitting, these basic elements are combined into the parameter of complete characterization
Change equation.According to some size of CAD design drawing requirement, the actual size of the size in feature is obtained, and by actual size
Size is contrasted with desired size, and cutter compensation amount can be calculated according to comparing result.
Beneficial effect
The utility model uses laser MEMS three-dimensional reconstructions, and the three-dimensional that can quickly and accurately reconstruct workpiece is special
Sign, under the premise of precision is ensured, relative to contact measuring head, the utility model can faster be realized and workpiece is looked for
Just measured with inter process, and the path planning of gauge head is simpler.
Brief description of the drawings
Fig. 1 gauge head shells
Composition schematic diagram inside Fig. 2 gauge heads
Wherein 1 is gauge head shell；2 be WIFI module；3 be MEMS projection arrangements；4 be lithium battery；5 be connecting plate；6 be intelligence
Can camera；7 be support plate；8 be transparent glass；9 be LED annular light sources.
Specific embodiment is as follows：
The first step:The calibration of relation between gauge head and lathe coordinate system
The calibration of relation is the basis that gauge head realizes centering between gauge head and lathe coordinate system.In order to try to achieve gauge head and lathe
Relation M between coordinate system, our the radius R of known standard ball are known, and machining center end effector mechanism is relative to machine
The pose of bed coordinate system can be obtained according to machine tool control cabinet, and known, be denoted as H.Standard ball is worked fixed to lathe
On platform, the center of circle of note standard ball at this time is C=(x relative to the coordinate of lathe coordinate systemc, yc, zc)T, standard is obtained using gauge head
The cloud data in some region of ball surface, the cloud data set that sets up an office are
P{p1(x1, y1, z1),{p1(x2,y2,z2),{p1(x3, y3, z3)……{pn(xn, yn, zn)},
It can be listed below equation
di=(HMPi-C)T(HMPi-C)-R2, i=1,2,3 ... ..n
H in above formula, M are 4X4 matrixes.Wherein M, C are unknown quantity, and being tried to achieve using iterative method makes diObtain minimum variance
When M, C matrixes, you can obtain transformational relation of the gauge head relative to lathe coordinate system.
Second step：Rebuild for the laser three-D of workpiece features
1, it is necessary to extract the two dimensional character of workpiece first before three-dimensional reconstruction is carried out to workpiece.Specific method is as follows：
1) extraction of edge feature
Edge is characterized in that smaller in edge triangular angular gradation of image step amplitude, and with the figure of edge-perpendicular angle
As Gray step amplitude is larger.Characteristic area is may determine that using the changing rule of first differential at image boundary or second-order differential
Border.Usual digital picture has many noises, and differentiating causes noise-sensitive to report many marginal points by mistake, tackles to figure
As doing convolution to filter off noise, then differential is done to the image after convolution and carrys out detected edge points.It is more according to the different generations of convolution mask
Kind Boundary extracting algorithm：First order differential operator has Kirsch operators, Canny operators.Second Order Differential Operator have LOG operators (Gauss-
Laplace operator) etc..The above method has carried out image whole pixel edge detection, on this basis, near marginal point
Image information realizes the edge detection of sub-pixel by the method based on interpolation, the method based on square, fitting process etc..
2) circle (point) extraction
By the detectable edge contour of above-mentioned edge detection method, according to bore edges contour pixel, pass through center of gravity
The methods of method, circle fitting process, hough conversion, obtains the pixel coordinate in the circular hole center of circle.
3) plane or curved surface extraction
The grey scale pixel value of plane or curved surface is all than more uniform on image, therefore threshold method can be used to carry out image
Segmentation, extracts plane characteristic.
Above-mentioned algorithm is implanted in gauge head in the embedded system of smart camera, smart camera is directly extracted
The features such as the point in image, line, face, and feature is become the effective coverage for image.
2, three-dimensional reconstruction is carried out to the feature extracted in image
According to the principle that the effective coverage of acquired image, can carry out the region according to binocular stereo vision three-dimensional
Rebuild, algorithm for reconstructing has been implanted in the embedded system of smart camera.Principle is as follows：
The image and the image of projection device collected to smart camera carries out polar curve and corrects to obtain the two of row alignment
Width image, the laser-knife center of collection effective image area, projected image laser-knife center are extracted using laser-knife center extraction algorithm
It is known.In the vision system being made of smart camera and micro- galvanometer laser-projector, using laser projection device as virtualphase
Machine, the inside and outside parameter of smart camera and projecting apparatus is calibrated by anti-phase machine calibration technique.According to inside and outside ginseng and two images
Laser-knife center, goes out the workpiece space three-dimensional coordinate that finishing tool covered using binocular stereo vision algorithm three-dimensional reconstruction, just obtains
The cloud data of feature on workpiece.Above-mentioned calculating is entirely to be carried out in gauge head in the embedded system of smart camera, is calculated
As a result it is wirelessly transmitted in host computer.
3rd step：Centering and the inter process measurement of workpiece
1, the centering of workpiece
Manually by blank clamping to workbench, found according to 6 method for centering using gauge head and establish workpiece coordinate system need
The element wanted, i.e. point, line, face, so as to establish with complete corresponding workpiece coordinate system on host computer.For example, have on a blank
Two circular holes can utilize three-dimensional as the benchmark for establishing workpiece coordinate system, contactless gauge head in one plane and plane
Reconstruction technique accurately extracts the point of plane A and the three-dimensional data of two circular holes B, C.These above-mentioned data are sat in gauge head
The lower foundation of mark system, it is also necessary to be transformed under lathe coordinate system.
Three-dimensional data under gauge head coordinate system is utilized into the result M of gauge head calibration and the pose of machining center end effector
H is transformed into Pmachine under lathe coordinate system, its coordinate transformation relation is
Pmachine=HM
Transformed A, B, C is now under unified lathe coordinate system, and to A, B, C carry out plane fitting respectively, circle
Fitting, obtains their mathematic(al) representation.Afterwards will circle B centre point upright projection to a point O is obtained on plane A, make the O points be
Workpiece coordinate system origin.The normal direction for making plane A is workpiece coordinate system Z-direction, the line projection between two circular hole centers of circle
The Y-axis of coordinate system is obtained to plane A, X-axis can then be determined according to right-hand rule, you can complete centering.
2, the inter process measurement of workpiece
These three-dimensional datas are handled in host computer.All three-dimensional datas are demarcated according to the first step first
To data be transformed under lathe coordinate system, carry out data fitting to it using least square method afterwards, including inside and outside circle, inside and outside
Ellipse fitting, fitting a straight line, plane, surface fitting, after the completion of fitting, obtain the mathematical model of these elements, utilize these yuan
The mathematical model of element can obtain being tested the mathematical model of feature on workpiece.For example, the circular hole of one Φ 60 of boring is needed on workpiece,
, it is necessary to measure the current diameter of this circular hole to judge the depth of cut of last knife before last knife is processed.Therefore, with survey
Head reconstructs the three-dimensional data of the circular hole, these data are carried out to justify fitting, obtain a round mathematic(al) representation, and be somebody's turn to do
Diameter of a circle R, is compared, you can judge the depth of cut of next step with this R with Φ 60.
Claims (2)
1. a kind of laser is in machine centering and inter process measuring device, it is characterised in that：It is made of laser feeler and host computer, laser
Include smart camera, MEMS scanning galvanometers projection arrangement, WIFI module and lithium battery, smart camera in gauge head to sweep with MEMS
Retouch galvanometer projection arrangement composition single camera vision system；The laser feeler is independent individual in off working state, is placed on
In the tool magazine of numerical control machining center；In working status, on the end effector of gauge head clamping to numerical control machining center；Described
Smart camera is made of general industry camera and embedded system.
2. if 1 laser of claims is in machine centering and inter process measuring device, it is characterised in that：The optical axis of the smart camera
Coplanar with the optical axis of MEMS scanning projection devices, the optical axis of MEMS scanning projection devices is vertical with transparent glass, LED annular light sources
Among smart camera and MEMS projection arrangements；WIFI module is fixed on connecting plate, and lithium battery is fixed on the rear wall of gauge head
On.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720589674.9U CN207319046U (en) | 2017-05-25 | 2017-05-25 | A kind of laser is in machine centering and inter process measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720589674.9U CN207319046U (en) | 2017-05-25 | 2017-05-25 | A kind of laser is in machine centering and inter process measuring device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN207319046U true CN207319046U (en) | 2018-05-04 |
Family
ID=62437128
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201720589674.9U Active CN207319046U (en) | 2017-05-25 | 2017-05-25 | A kind of laser is in machine centering and inter process measuring device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN207319046U (en) |
-
2017
- 2017-05-25 CN CN201720589674.9U patent/CN207319046U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107121967A (en) | A kind of laser is in machine centering and inter process measurement apparatus | |
| Jiang et al. | A method of testing position independent geometric errors in rotary axes of a five-axis machine tool using a double ball bar | |
| CN109489580A (en) | A kind of processing of complex surface in machine point cloud detection and compensation method | |
| CN104567679B (en) | A kind of system of turbo blade vision-based detection | |
| CN208780144U (en) | A kind of online vision detection system of connecting hole | |
| CN109684709B (en) | Self-adaptive positioning method for repairing aero-engine blade | |
| CN106600681A (en) | A method for polishing a curved surface having obstacles | |
| CN105447910B (en) | A kind of aero-engine compressor blade tip defect three-dimensional rebuilding method | |
| SE461548B (en) | PROCEDURE AND DEVICE FOR DETERMINING AND CORRECTING IN CASE OF LOCATION ERROR IN SEATING A POINT OF A POINT OR POSITIONING TO A POINT WITH A PARTICULAR LOCATION | |
| CN112614098B (en) | Blank positioning and machining allowance analysis method based on augmented reality | |
| CN108994830A (en) | System calibrating method for milling robot off-line programing | |
| US7905031B1 (en) | Process for measuring a part | |
| CN103615980A (en) | Method and system for measuring parameters of round holes in plate | |
| CN103148784A (en) | Full size detection method for large vane | |
| de Araujo et al. | Computer vision system for workpiece referencing in three-axis machining centers | |
| CN110081821A (en) | Intelligent high-speed rail white body assembling quality detection device and its method | |
| CN113375594B (en) | Aircraft skin profile digital detection method | |
| CN106705880B (en) | A kind of large caliber reflecting mirror face shape profile detection method and device in place | |
| CN111338290A (en) | Multi-vision-based five-axis numerical control machine tool multifunctional detection method | |
| CN110375674A (en) | A kind of vision detection system of precision manufactureing equipment | |
| CN104503367A (en) | Turbine blade processing and on-line detection system based on numerical control processing device | |
| CN211827005U (en) | Multi-functional detection device of five-axis numerical control machine tool based on multi-eye vision | |
| CN111008602B (en) | Scribing feature extraction method combining two-dimensional vision and three-dimensional vision for small-curvature thin-wall part | |
| CN204514271U (en) | A kind of system of turbo blade vision-based detection | |
| CN111069973B (en) | Method and device for quickly aligning complex-shape casting |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |