CN114674227B - Method and device for calibrating axis error of rotary table - Google Patents
Method and device for calibrating axis error of rotary table Download PDFInfo
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Abstract
The invention discloses a method and a device for calibrating an axis error of a rotary table. The method comprises the following steps: (1) Acquiring image information of the rotary table at an initial angle and at an initial Z-axis position of the camera, (2) rotating the rotary table in one direction and enabling the camera to rotate along with the rotary table to acquire interval preset anglesObtaining the rotation center of the rotary table at the Z-axis position by using a plurality of rotary table image information of the degree; (3) Moving the camera vertically moves the camera to a next Z-axis position Z 1 Acquiring image information of a plurality of turntables at preset angles, (4) repeating the step (3) to obtain a plurality of turntable rotation centers at different Z-axis positions; (5) Fitting the rotating centers of the rotary tables at the Z-axis positions into an axis, obtaining an intersection point of the axis and a plane where the Z-axis position is located, wherein the vector difference between the intersection point and the rotating center of the rotary table at the Z-axis position is the error on the plane. The invention realizes convenient and stable long-distance error calibration of the rotary table.
Description
Technical Field
The invention belongs to the technical field of measurement precision control, and particularly relates to a method and a device for calibrating an axis error of a rotary table.
Background
The rotary table is an important component of the revolving body measuring instrument, and the revolving precision of the rotary table directly influences the measuring precision of the measuring instrument, so that the rotary table is very important for the calibration of the rotary table. In recent years, the development of the rotary table angle measurement and calibration technology is rapid, and circular grating angle measurement, laser interferometry, self-collimation measurement, optical internal reflection angle measurement and the like are provided. In addition to the influence of the angle, the swing phenomenon of the turntable caused by manufacturing and installation, namely the deviation of the spindle rotation axis of the turntable from the design theoretical axis of the turntable, limits the performance of the instrument. The research on axis error calibration is less at present, and the old and cool et al propose an axis error calibration method based on parameter estimation, and use the geometric center line of a physical standard to represent a virtual axis, but the process is complex, a six-axis motion platform is needed, the control precision requirement is extremely high, and the geometric center line of the standard cannot completely represent the specific situation of the axis on each section. In addition, the method has a good data effect on a near-table surface, and is not applicable to a method using a standard device for error calibration of a long distance of a turntable axis required by a large workpiece.
Therefore, a scheme for calibrating the axis error of the rotary table, which is convenient and stable and can ensure the long-distance calibration precision, is needed.
Disclosure of Invention
Aiming at the defects or the improvement requirements of the prior art, the invention provides a method and a device for calibrating the axis error of a rotary table, aiming at calibrating by adding a space straight line reference and matching a camera, and rapidly obtaining the error on any section by a mode of fitting the axis after obtaining the rotation center of each section, thereby being beneficial to improving the precision of subsequent measurement. The problem that the specific conditions of the axis on each section cannot be completely characterized at present is solved.
To achieve the above object, according to one aspect of the present invention, there is provided a turntable axis error calibration method, including the steps of:
(1) Acquiring the initial angle of the rotary table (5) and the initial Z-axis position Z of the camera (8) 0 The image information of the time-lapse rotary table comprises an image containing light spots, and the light spots are formed by straight lines of diffraction-free light beams vertically penetrating through a circular hole in the center of the rotary table (5) from bottom to top;
(2) Rotating the rotary table (5) towards one direction and enabling the camera (8) to rotate along with the rotary table to obtain a plurality of rotary table image information at intervals of preset angles until the rotary table (5) returns to the initial angle; to the initial Z-axis position Z 0 After central extraction algorithm processing is carried out on the image information of the next plurality of turntables, averaging processing is carried out to obtain the rotation center of the turntables at the Z-axis position;
(3) Moving the camera vertically moves the camera to a next Z-axis position Z 1 The method comprises the steps of obtaining rotary table image information of a rotary table (5) at an initial angle, then rotating the rotary table (5) towards one direction and enabling a camera (8) to rotate along with the rotary table, and obtaining a plurality of rotary table image information at intervals of preset angles until the rotary table returns to the initial angle;
(4) After the step (3) is repeated, the same data processing in the step (2) is carried out to obtain a plurality of rotary centers of the rotary table at different Z-axis positions;
(5) Fitting the rotating centers of the rotary tables at a plurality of Z-axis positions into one axis, and acquiring an intersection point of the axis and a plane where the Z-axis position is located, wherein the vector difference between the intersection point and the rotating center of the rotary table at the Z-axis position is the error on the plane.
According to the invention, the calibration is carried out by adding the space linear reference in cooperation with the camera, so that the error on any section can be quickly obtained, and the accuracy improvement of subsequent measurement is facilitated. The space linear reference can be used as a reference in the calibration process and can also be used as a reference in subsequent measurement, errors obtained in the calibration process can be unified to a coordinate system formed by stretching the space reference, and error compensation can be directly performed on the basis of the space linear reference in the subsequent measurement, so that the method has the advantages of convenience, high precision and the like.
Preferably, the step (2) is performed for an initial Z-axis position Z 0 After center extraction algorithm processing is carried out on a plurality of rotary table image information, averaging processing is carried out to obtain a rotary table rotation center under the Z-axis position, and the method specifically comprises the following substeps:
(201) To the initial Z-axis position Z 0 After diffraction light center extraction algorithm processing is carried out on a plurality of turntable image information, equalization processing is carried out to obtain plane coordinates of the reference center in each image under a camera coordinate system
Wherein m is an integer not zero;
(202) The rotation center coordinates of the turntable are calculated according to the following formula
Wherein i and j are integers not equal to zero;
(203) The rotation center coordinates of a plurality of rotary tables are equalized to obtain the final rotation center coordinate (A) of the rotary table at the Z-axis position o ,B o )。
Preferably, the step (201) is specifically: obtaining the pixel coordinates (u, v) of a reference center in the image through a non-diffraction light center extraction algorithm, and obtaining the coordinates (x, y) of the reference center in an image size coordinate system through the following formula:
wherein (u) 0 ,v 0 ) Dx and dy are the physical dimensions of each pixel in the x-axis and y-axis directions, which are the positions of the optical centers in the pixel coordinate system;
then, the coordinates (x, y) of the reference center in the image size coordinate system are converted into plane coordinates (x, y) in the camera coordinate system c ,y c )；
Wherein z is c The distance from the optical center of the camera to the light spot, and f is the focal length of the camera. In the invention, as no diffracted light is directly irradiated to the target surface of the camera for imaging, zc and f are equal, and Zc/f =1.
Preferably, said step (5) further comprises the sub-steps of:
(501) Projecting the rotating center of the rotary table at a plurality of Z-axis positions into a three-dimensional coordinate under a measurement coordinate system;
(502) Fitting the rotating centers of the rotary table at a plurality of Z-axis positions into one axis by adopting a least square method or a gradient descent method;
(503) And acquiring an intersection point of the axis and a plane where the Z-axis position is located, wherein the vector difference between the intersection point and the rotary center of the rotary table at the Z-axis position is the error on the plane, and the direction and the mode of the vector are the direction and the magnitude of the error.
According to another aspect of the present invention, there is provided a rotary table axis error calibration apparatus, including a spatial linear reference generator assembly, a guide rail, a moving sliding table, a camera, and a data acquisition and processing unit, wherein:
the space straight line reference generator assembly is used for emitting a straight line of diffraction-free light beams, and the straight line of the diffraction-free light beams penetrates through a circular hole in the center of the rotary table;
the guide rail is connected with the rotary table and synchronously rotates along with the rotary table, the guide rail is vertical to the table surface of the rotary table, and the guide rail is provided with a displacement sensor; the camera is connected to the movable sliding table, and the position of the camera can meet the requirement that a lens of the camera can acquire a light spot image containing a diffraction-free light beam straight line;
the data acquisition and processing unit is used for receiving image information acquired by the camera, displacement information of the mobile station on the guide rail and circle grating scale information of the rotary table and obtaining the axis error of the rotary table.
Preferably, the displacement sensor is a grating line displacement sensor.
Preferably, the spatial straight reference generator assembly comprises a diffraction-free spatial straight reference generator and a mirror; the reflector is used for enabling the undiffracted light beam emitted by the undiffracted light space linear reference generating device to linearly pass through the circular hole in the center of the turntable.
In general, at least the following advantages can be obtained by the above technical solution contemplated by the present invention compared to the prior art.
(1) The invention unifies the errors to the coordinate system which is formed by stretching the space straight line standard as the reference standard, and the errors on any section can be rapidly obtained, the invariable space straight line standard can be shared in the calibration process and the subsequent measurement process, and the invention is more beneficial to data processing and error elimination. The invention unifies errors to the error elimination when the homogenized actual rotation center of the main shaft of the rotary table is used as a correction value for the actual measurement of the rotary table, and the errors of all the sections are obtained, and then the error correction can be respectively carried out on the measurement of all the sections. Meanwhile, the device and the method for calibrating the axis error of the turntable take the non-diffraction light beam as a reference, have imaging stability, good containment on manufacturing and mounting errors of optical devices and long propagation distance, are suitable for being used as a reference for measuring spatial errors, and can calibrate the error in a large range and a long distance.
(2) The invention directly uses the camera and the non-diffraction light linear reference to observe the rotary motion of the rotary table, does not need to introduce a third-party standard component to represent the axial motion of the rotary table, and avoids the introduction of errors of the standard component.
Drawings
FIG. 1 is a schematic view of the apparatus for calibration with turntable axis error calibration of the present invention;
fig. 2 is a schematic diagram of the arrangement of the measuring points of the present invention.
The same reference numbers will be used throughout the drawings to refer to the same or like elements or structures, wherein:
1-a frame, 2-a diffraction-free light space straight line reference generating device, 3-a reflector, 4-a diffraction-free light beam, 5-a turntable, 6-a guide rail, 7-a moving sliding table and 8-a camera;
h represents the horizontal section measurement point, and T represents the measurement angle of the same section.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
The laser alignment technology is a measurement reference for geometric parameters and form and position errors of large workpieces, and an optical linear basis with high precision and high stability is used as a guarantee. The non-diffraction light technique is a new technique in the field of optical measurement, and is characterized by that the laser can be passed through some special optical elements so as to produce a light beam whose light spot form does not change with the change of propagation distance. The optical distribution of the beam cross section is Bessel function, and the cross section is shaped like a concentric ring. The central light spot is small, the collimation degree is high, the cross section shape is stable, and the drift influence of the laser can be effectively reduced under the aperture with the same objective numerical value. Therefore, the non-diffraction light is more suitable as a straight line reference for medium and long distance optical measurement, and the axial working distance can be larger than 65m.
Based on this, the present invention uses the undiffracted light as a spatial straight reference.
The embodiment of the invention provides a rotary table axis error calibration device, which comprises a space linear reference generator assembly, a guide rail 6, a movable sliding table 7, a camera 8 and a data acquisition and processing unit, and is shown in figure 1, wherein: the space straight line reference generator assembly is used for emitting a straight line of the diffraction-free light beam, and the emitted diffraction-free light beam penetrates through a circular hole in the center of the rotary table 5; the guide rail 6 is connected with the rotary table 5 and synchronously rotates along with the rotary table 5, the guide rail 6 is vertical to the table surface of the rotary table 5, and the guide rail 6 is provided with a displacement sensor; the movable sliding table 7 is arranged on the guide rail 6 and can move along the guide rail, the camera 8 is connected to the movable sliding table 7, and the position of the camera 8 can meet the requirement that a lens of the camera can acquire light spots containing diffraction-free light beam straight lines; the data acquisition and processing unit is used for receiving image information acquired by the camera, displacement information of the mobile station on the guide rail and circle grating scale information of the rotary table and obtaining the axis error of the rotary table 5.
Preferably, the displacement sensor is a grating line displacement sensor.
Wherein the spatial straight reference generator assembly comprises a diffraction-free spatial straight reference generator 2 and a reflector 3; the reflector 3 is used for enabling the diffraction-free light beam emitted by the diffraction-free light space straight line reference generating device 2 to pass through a circular hole in the center of the turntable 5 in a straight line.
The embodiment of the invention provides a method for calibrating an error of a rotary table axis, which comprises the following steps:
step (1): acquiring the initial angle of the turntable 5 and the initial Z-axis position Z of the camera 8 0 The image information of the turntable comprises images containing light spots, and the light spots are formed by straight non-diffracted light beams vertically penetrating through a circular hole in the center of the turntable 5 from bottom to top.
Specifically, measurement points representing the horizontal cross-sectional positions, which are respectively denoted as H, are arranged on the guide rail 0 ,H 1 …H n The measuring angles are respectively marked as T along the rotation direction of the rotary table 0 ,T 1 …T m Is composed of a pair of (H) n ,T m ) A unique measurement location can be determined. The measurement angles are respectively equidistant and equiangular for calculation and operation. For example, H0, H1 in FIG. 2,H2 H0 may be, for example, the initial Z-axis position Z 0 . And the zero position of the rotary table is used as an initial setting measuring angle used by the CCD camera, and the measuring point and the measuring angle respectively cover the whole guide rail and the rotary table. And rotating the rotary table to a zero position, installing a calibration device, and taking the relation between a camera coordinate system and a set measurement coordinate system into consideration when the CCD camera is placed on the mobile table so that the coordinate axes of the camera coordinate system and the set measurement coordinate system are parallel to each other in the same direction.
And (2) rotating the rotary table 5 towards one direction and enabling the camera 8 to rotate along with the rotary table, and acquiring a plurality of rotary table image information at intervals of preset angles until the rotary table 5 returns to the initial angle. To the initial Z-axis position Z 0 And after center extraction algorithm processing is carried out on the image information of the plurality of rotary tables, averaging processing is carried out to obtain the rotary center of the rotary table at the Z-axis position.
The CCD camera with the H0 section rotates along with the rotary table and shoots images at set measuring angular positions, such as T0, T1, T2, T3, T4, T5, T6 and T7, and the space straight line reference generator assembly is kept unchanged in the whole process. The driving mobile station is to measuring point H0 on the guide rail, and the revolving stage rotates with steady speed from the zero position after waiting to stabilize, is got for instance and is received by the acquisition unit by the camera according to circle grating reading, gets back to the zero position again after a week is accomplished. Respectively obtaining images
Image at each cross-sectional zero position
Used for establishing the relation between the image coordinate system and the coordinate system spanned by the space reference. When the camera moves in the vertical direction, the camera may have offset in the x and y directions, and the image of the zero position of different cross sections can be seen to correct the movement change.
The data processing of step (2) specifically includes the following sub-steps:
(201) To the initial Z-axis position Z 0 Multiple turret image information
Is subjected to diffractionAfter the processing of the light emitting center extraction algorithm, carrying out equalization processing to obtain the plane coordinate (based on the camera coordinate system) of the reference center in each image>
Wherein m is an integer not zero;
the step (201) is specifically as follows: obtaining pixel coordinates (u, v) of a reference center in the image by a non-diffraction light center extraction algorithm, and obtaining coordinates (x, y) of the reference center in an image size coordinate system by the following formula:
wherein (u) 0 ,v 0 ) Dx and dy are the physical dimensions of each pixel in the x-axis and y-axis directions, which are the positions of the optical centers in the pixel coordinate system; u. of 0 、v 0 And dx and dy are calibration parameters carried by the camera.
Then, the coordinates (x, y) of the reference center in the image size coordinate system are converted into plane coordinates (x) in the camera coordinate system c ,y c )；
Wherein z is c The distance from the optical center of the camera to the light spot, and f is the focal length of the camera. In the invention, as no diffracted light is directly irradiated to the target surface of the camera for imaging, zc and f are equal, and Zc/f =1.
(202) Calculating the rotation center coordinates of the turntable according to the following formula
Marking the rotation center coordinate of the turntable by the serial number i of the measuring point and the serial number j of the measuring angle
For each cross sectionVolume point i, requiring three sets of coordinates for determining the coordinates of the rotation center &>
One group of three groups of coordinates is a reference center coordinate of the initial position>
The other two groups can arbitrarily select two groups of non-repeated reference center coordinates->
Wherein i and j are integers not equal to zero;
(203) The rotation center coordinates of a plurality of rotary tables are equalized to obtain the final rotation center coordinate (A) of the rotary table at the Z-axis position o ,B o )。
A group of central coordinate sets can be obtained through different combination modes of i and j, and points with larger spacing are generally selected for combination so as to reduce errors and improve the stability of the algorithm. The final rotating center coordinate (A) of the rotary table at the Z-axis position is obtained by carrying out equalization processing on the center coordinate set o ,B o )。
Step (3), vertically moving the camera to move the camera to the next Z-axis position Z 1 The method comprises the steps of obtaining rotary table image information of a rotary table (5) at an initial angle, then rotating the rotary table (5) towards one direction and enabling a camera (8) to rotate along with the rotary table, and obtaining a plurality of rotary table image information at intervals of preset angles until the rotary table returns to the initial angle.
The moving sliding table ascends from the bottom of the guide rail to reach each horizontal section position, such as H1 and H2, the CCD camera in the H1 section rotates along with the rotary table and shoots images at the set measuring angle positions, such as T0, T1, T2, T3, T4, T5, T6 and T7, and the spatial straight line reference generator assembly is kept unchanged in the whole process. Pictures of different angles are taken on the H2 section in the same way.
Step (4), after the step (3) is repeated, the same data processing in the step (2) is carried out to obtain a plurality of rotary centers of the rotary table at different Z-axis positions;
obtaining the final rotating center coordinate (A) of each section by using the same data processing mode as that in the step (2) o ,B o ) (A 1 ,B 1 ) ... (A n ,B n )。
And (5) fitting the rotating centers of the rotary tables at the plurality of Z-axis positions into one axis, obtaining an intersection point of the axis and a plane where the Z-axis position is located, wherein the vector difference between the intersection point and the rotating center of the rotary table at the Z-axis position is the error on the plane.
The step (5) further comprises the following substeps:
(501) The relationship between the coordinate system of the measurement and the coordinate system of the camera, which is obtained by calibration during the arrangement of the device, can project the rotation center of the rotary table at a plurality of Z-axis positions into three-dimensional coordinates (A) in the coordinate system of the measurement i ,B i ,Z i )；
(502) Fitting the rotating centers of the rotary table at a plurality of Z-axis positions into one axis by adopting a least square method or a gradient descent method; the expression for this axis is the following system of equations: ax + by + cz = d, and mx + ny + oz = p.
(503) And acquiring an intersection point of the axis and a plane where the Z-axis position is located, wherein the vector difference between the intersection point and the rotary center of the rotary table at the Z-axis position is the error on the plane, and the direction and the mode of the vector are the direction and the magnitude of the error.
Specifically, the Z value recorded at each cross-sectional zero position is the plane in which the Z-axis position lies, for example, the cross-section represented by Z =1,z = 3.
The axis expression obtained by the fitting of step (502) is ax + by + cz = d; and mx + ny + oz = p. The intersection point (x, y) can thus be obtained by combining the section expression z = k.
The axis equation is used to obtain the intersection point with each section (for example, the plane where H0, H1 and H2 are located)
And the rotation center coordinate (A) i ,B i ) The vector difference of the two points is the error of the section, and the direction and the mode of the vector are the direction and the magnitude of the error. Therefore, after the error of each section is obtained, the error correction can be respectively carried out on the measurement of each section, and more complete error compensation can be carried out compared with the traditional error mode that the whole body shares the near table top (the traditional mode considers that the whole errors of the axes are approximately the same, the actual axis errors are different in each section, the near table top is smaller, and the longer the distance is, the larger the error is).
The principle of error measurement of the invention is as follows: the method is characterized in that undiffracted light emitted by a undiffracted light straight line reference is used as a space reference, a CCD camera can obtain images of undiffracted light beams at any angle and at any height through the matching of a guide rail and a movable sliding table, a fixed point, namely a rotation center, on each section is obtained through an image set, an ideal axis of the turntable is fitted, and an error is obtained through the actual rotation center position and the ideal rotation center position of each section.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (7)
1. A method of calibrating turret axis error, the method comprising the steps of:
(1) Acquiring the initial angle of the rotary table (5) and the initial Z-axis position Z of the camera (8) 0 The image information of the time-lapse rotary table comprises an image containing light spots, and the light spots are formed by straight lines of diffraction-free light beams vertically penetrating through a circular hole in the center of the rotary table (5) from bottom to top;
(2) Rotating the rotary table (5) towards one direction and enabling the camera (8) to rotate along with the rotary table to obtain a plurality of rotary table image information at intervals of preset angles until the rotary table (5) returns to the initial angle; to the initial Z-axis position Z 0 After central extraction algorithm processing is carried out on a plurality of rotary table image information, averaging processing is carried out to obtain an initial Z-axis position Z 0 The rotation center of the lower turntable;
(3) Moving the camera vertically moves the camera to a next Z-axis position Z 1 The method comprises the steps of obtaining rotary table image information of a rotary table (5) at an initial angle, then rotating the rotary table (5) towards one direction and enabling a camera (8) to rotate along with the rotary table, and obtaining a plurality of rotary table image information at intervals of preset angles until the rotary table returns to the initial angle;
(4) After the step (3) is repeated, the same data processing in the step (2) is carried out to obtain a plurality of rotary centers of the rotary table at different Z-axis positions;
(5) Fitting the rotating centers of the rotary tables at the Z-axis positions into an axis, obtaining an intersection point of the axis and a plane where the Z-axis position is located, wherein the vector difference between the intersection point and the rotating center of the rotary table at the Z-axis position is the error on the plane.
2. The method of claim 1, wherein step (2) is performed for an initial Z-axis position Z 0 After central extraction algorithm processing is carried out on the image information of the plurality of rotary tables, averaging processing is carried out to obtain an initial Z-axis position Z 0 The rotary center of the rotary table comprises the following substeps:
(201) To the initial Z-axis position Z 0 After diffraction light center extraction algorithm processing is carried out on a plurality of turntable image information, equalization processing is carried out to obtain plane coordinates of the reference center in each image under a camera coordinate system
Wherein m is an integer not zero;
(202) Calculating the rotation center coordinates of the turntable according to the following formula
Wherein i and j are integers not zero;
(203) Carrying out equalization processing on the rotation center coordinates of a plurality of rotary tables to obtain an initial Z-axis position Z 0 Final turntable rotation center coordinates (A) of o ,B o )。
3. The method according to claim 2, characterized in that said step (201) is in particular: obtaining pixel coordinates (u, v) of a reference center in the image by a non-diffraction light center extraction algorithm, and obtaining coordinates (x, y) of the reference center in an image size coordinate system by the following formula:
wherein (u) 0 ,v 0 ) Dx and dy are the physical dimensions of each pixel in the x-axis and y-axis directions, which are the positions of the optical centers in the pixel coordinate system;
then, the coordinates (x, y) of the reference center in the image size coordinate system are converted into plane coordinates (x) in the camera coordinate system c ,y c )；
Wherein z is c The distance from the optical center of the camera to the light spot, and f is the focal length of the camera.
4. The method according to claim 1, wherein said step (5) further comprises the sub-steps of:
(501) Projecting the rotating center of the rotary table at a plurality of Z-axis positions into a three-dimensional coordinate under a measurement coordinate system;
(502) Fitting the rotating centers of the rotary table at a plurality of Z-axis positions into one axis by adopting a least square method or a gradient descent method;
(503) And acquiring an intersection point of the axis and a plane where the Z-axis position is located, wherein the vector difference between the intersection point and the rotary center of the rotary table at the Z-axis position is the error on the plane, and the direction and the mode of the vector are the direction and the magnitude of the error.
5. The utility model provides a revolving stage axis error calibrating device which characterized in that, includes space straight line benchmark generator module, guide rail (6), removes slip table (7), camera (8) and data acquisition processing unit, wherein:
the space straight line reference generator assembly is used for emitting a straight line of diffraction-free light beams, and the straight line of the diffraction-free light beams penetrates through a circular hole in the center of the rotary table (5);
the guide rail (6) is connected with the rotary table (5) and synchronously rotates along with the rotary table (5), the guide rail (6) is vertical to the table surface of the rotary table (5), and the guide rail (6) is provided with a displacement sensor; the movable sliding table (7) is arranged on the guide rail (6) and can move along the guide rail, the camera (8) is connected to the movable sliding table (7), and the position of the camera (8) can meet the requirement that a lens of the camera can acquire an image containing a light spot without a diffraction light beam straight line;
the data acquisition and processing unit is used for receiving image information acquired by the camera, displacement information of the mobile station on the guide rail and circle grating scale information of the rotary table, and obtaining the axis error of the rotary table (5) according to the method of any one of claims 1 to 4.
6. The turntable axis error calibration device of claim 5, wherein the displacement sensor is a grating line displacement sensor.
7. Turntable axis error calibration device according to claim 5, characterized in that said spatial straight reference generator assembly comprises a diffraction-free spatial straight reference generating device (2) and a mirror (3); the reflector (3) is used for enabling the undiffracted light beam emitted by the undiffracted light space linear reference generating device (2) to linearly pass through a circular hole in the center of the turntable (5).
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| CN202210306067.2A CN114674227B (en) | 2022-03-25 | 2022-03-25 | Method and device for calibrating axis error of rotary table |
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| AU2002349831A1 (en) * | 2002-10-11 | 2004-05-04 | Fidia S.P.A. | System and process for measuring, compensating and testing numerically controlled machine tool heads and/or tables |
| JP4419570B2 (en) * | 2003-12-26 | 2010-02-24 | 富士ゼロックス株式会社 | 3D image photographing apparatus and method |
| CN109238157B (en) * | 2018-09-10 | 2020-04-10 | 耿佳钰 | Turntable radius and installation eccentric four-index coordinate increment detection method and detection device |
| CN209842399U (en) * | 2018-10-15 | 2019-12-24 | 天津大学 | Calibrating device for geometric error of machine tool and corner positioning error of rotary table |
| CN109520417A (en) * | 2018-10-15 | 2019-03-26 | 天津大学 | Lathe geometric error and turntable corner position error calibrating installation and method |
| CN111272095B (en) * | 2020-02-24 | 2022-03-29 | 中国科学院光电技术研究所 | High-precision two-dimensional position sensor centering detection device and method |
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