A method for calibrating an angular position parameter of a rotating platform

Abstract

The application discloses a kind of rotary platform angular position parameter calibration methods, comprising: the rotary platform to be calibrated is connected with coordinate measuring machine, and multiple high-precision positioning standard balls are fixed around the rotary platform to be calibrated;The high-precision positioning standard ball is measured by the coordinate measuring machine, and the initial coordinate system when the rotary platform is stationary is calculated and determined;The rotary shaft and the pitch axis of the rotary platform are moved at fixed angle intervals, the high-precision positioning standard ball after each movement is measured by the coordinate measuring machine, and the pose coordinate system after the rotary shaft and the pitch axis are moved is established;The angular position parameters of the rotary shaft and the pitch axis are precisely calibrated by the attitude change of the high-precision positioning standard ball.The application can calibrate angular position parameters in situ using coordinate measuring machine, and improve the calibration efficiency of the measured rotary shaft angular position parameters.

Description

Technical Field

[0001] This invention belongs to the field of geometric calibration, and specifically relates to a method for calibrating the angular position parameters of a rotating platform. Background Technology

[0002] As a common auxiliary testing device for coordinate measuring machines, the angular position of a rotary platform is an important working state. The positioning error is a combination of measurement error and control error, and its positioning accuracy directly affects the accuracy of component testing. Therefore, the calibration of the angular position parameters of different rotating axes is an essential task.

[0003] Currently, various methods exist for angular position calibration in engineering applications, such as the photoelectric autocollimator and polyhedral prism method, laser interferometric rotation measurement method, and laser tracker calibration method. Among these, the low-speed calibration specification uses a prism and a light tube to calibrate the angular position positioning parameters. The calibration steps involve installing the prism at the center of rotation of the measured axis, mounting the light tube on a well-isolated foundation, and ensuring the light tube's optical axis is perpendicular to the prism or plane mirror. Starting from the 0 position on the digital display of the angle measurement system, the initial reading of the light tube and the angle value of the measuring system are recorded. Then, the axis is rotated by the specified angle on the prism face, and the readings of the light tube and the measuring system are recorded. One revolution is measured forward and then one revolution backward. The angular position positioning error is taken as half of the maximum and minimum errors at each calibration point as the calibration result. This angular position calibration process is relatively complicated, requires high operator skills and a well-isolated environment, and necessitates delivery for inspection, making in-situ calibration of the angular position parameters impossible. Summary of the Invention

[0004] The purpose of this invention is to provide a method for calibrating the angular position parameters of a rotating platform, which can use a coordinate measuring machine to calibrate the angular position parameters in situ, thereby improving the calibration efficiency of the angular position parameters of the measured rotating axis.

[0005] To achieve the above objectives, one aspect of the present invention provides a method for calibrating the pose of a rotating platform, comprising:

[0006] Step S1: Connect the rotary platform to be calibrated to the coordinate measuring machine, and fix multiple high-precision positioning standard balls around the rotary platform to be calibrated.

[0007] Step S2: Measure the high-precision positioning standard sphere using a coordinate measuring machine, and calculate and determine the initial coordinate system when the rotating platform is stationary.

[0008] Step S3, using the pose change of the high-precision positioning standard ball before and after the rotation axis of the rotating platform moves, calibrate the angular position parameters of the rotation axis of the rotating platform, including:

[0009] The rotation axis of the rotating platform is moved at fixed angular intervals, and the high-precision positioning standard ball after each movement is measured by a coordinate measuring machine to obtain measurement data;

[0010] Gaussian fitting was performed on the measurement data of the high-precision positioning standard sphere to calculate the coordinates of each sphere's center point;

[0011] The coordinate system of the rotating platform after its rotation axis motion is determined based on the coordinates of each sphere's center point.

[0012] Based on the initial coordinate system Coordinate system after rotation axis motion Calculate and determine the transformation matrix of the first coordinate system;

[0013] Based on the calculated first coordinate system transformation matrix, the high-precision positioning standard sphere is positioned in the initial coordinate system. The rotation parameters are used to calculate the position of the rotation axis in the initial coordinate system after it moves at fixed angular intervals. The rotation parameters are used to calculate the rotation angle, and the angular position parameters of the rotary platform's rotation axis are calibrated.

[0014] Step S4, using the pose change of the high-precision positioning standard ball before and after the pitch axis movement of the rotating platform, calibrate the pitch axis angular position parameters of the rotating platform, including:

[0015] The pitch axis of the rotating platform is moved at fixed angular intervals, and the coordinate measuring machine measures the high-precision positioning standard ball after each movement to obtain measurement data;

[0016] The coordinates of the sphere's center point are calculated by fitting the measurement data of the high-precision positioning standard sphere.

[0017] Determine the coordinate system of the rotating platform after its pitch axis motion based on the coordinates of each sphere's center point.

[0018] Based on the initial coordinate system coordinate system after pitch axis motion Calculate and determine the transformation matrix of the second coordinate system;

[0019] Based on the calculated second coordinate system transformation matrix, the high-precision positioning standard sphere is positioned in the initial coordinate system. The rotation parameters are used to calculate the pitch axis position in the initial coordinate system after moving at fixed angular intervals. The rotation parameters are used to calculate the rotation angle, and the angular position parameters of the pitch axis of the rotating platform are calibrated.

[0020] Preferably, step S2 includes:

[0021] The pose of the rotating platform is zeroed, and the high-precision positioning standard ball is measured by a coordinate measuring machine to obtain the measurement data of the high-precision positioning standard ball;

[0022] Gaussian fitting was performed on the measurement data of the high-precision positioning standard sphere to calculate the coordinates of each sphere's center point;

[0023] Determine the coordinate system of the rotating platform when it is stationary based on the coordinates of each sphere's center point.

[0024] Preferably, three high-precision positioning standard spheres are used, and the coordinates of the center points of the three spheres when stationary are A, B, C, D, E, F, G, M, F, G, M, G ... 11 A 12 A 13 The coordinate system when the rotating platform is stationary The corresponding coordinate system matrix is ​​[A 12 -A 11 V calm11 V calm12 ],in,

[0025] V calm11 =(A 12 -A 11 )×(A 13 -A 11 V calm12 =(A 12 -A 11 )×V calm11 .

[0026] Preferably, in step S3, after the rotating shaft moves at fixed angular intervals, the coordinates of the three sphere centers are A1, A2, A3, A4, A5, A6, A7, A8, A9, A1 ... 21 A 22 A 23 Then the coordinate system after the rotation axis has moved The corresponding coordinate system matrix is ​​[A 22 -A 21 V calm21 V calm22 ], where V calm21 =(A 22 -A 21 )×(A 23 -A 21 V calm22 =(A 22 -A 21 )×V calm21 ;

[0027] The transformation matrix for the first coordinate system is:

[0028]

[0029] Wherein, λ1 is the first scaling parameter, R1 is the first rotation parameter, and Δ1 is the first translation vector;

[0030] X1, Y1, and Z1 are the initial coordinate system. Point A below 11 A 12 A 13 The X, Y, and Z coordinate values;

[0031] X2, Y2, and Z2 are the coordinate systems after the rotation axis has moved. Point A below 21 A 22 A 23 The X, Y, and Z coordinate values.

[0032] Preferably, in step S4, after the pitch axis moves at fixed angular intervals, the coordinates of the three sphere centers are A1, A2, A3, A4, A5, A6, A7, A8, A9, A1 ...1, A9, A1, A1, A1, A1, A1 31 A 32 A 33 Then the coordinate system after pitch axis motion The corresponding coordinate system matrix is ​​[A 32 -A 31 V calm31 V calm32 ], where V calm31 =(A 32 -A 31 )×(A 33 -A 31 V calm32 =(A 32 -A 31 )×V calm31 ;

[0033] The second coordinate transformation matrix is:

[0034]

[0035] Where λ2 is the second proportional parameter, R2 is the second rotation parameter, and Δ2 is the second translation vector;

[0036] X1, Y1, and Z1 are the initial coordinate system. Point A below 11 A 12 A 13 The X, Y, and Z coordinate values;

[0037] X3, Y3, and Z3 are the coordinate systems after pitch axis motion. Point A below 31 A 32 A 33 The X, Y, and Z coordinate values.

[0038] Preferably, the fixed angle interval is 30°.

[0039] Preferably, in step S1, the high-precision positioning standard ball is rigidly connected to the rotating platform through a rigid support to ensure that the high-precision positioning standard ball and the rotation axis and pitch axis of the rotating platform are always in the same coordinate system.

[0040] According to the rotary platform angular position parameter calibration method of the present invention described above, the angular position parameters can be calibrated in situ using a coordinate measuring machine, thereby improving the calibration efficiency of the measured rotary axis angular position parameters. Attached Figure Description

[0041] To more clearly illustrate the technical solutions of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort:

[0042] Figure 1 This is a flowchart of a method for calibrating the angular position parameters of a rotating platform according to an embodiment of the present invention;

[0043] Figure 2 This is a schematic diagram illustrating the application of a rotating platform angular position parameter calibration method according to an embodiment of the present invention. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0045] One embodiment of the present invention provides a method for calibrating the angular position parameters of a rotating platform, thereby calibrating the angular position parameters of the rotation axis and pitch axis of the rotating platform. For example... Figure 1 As shown, the rotary platform angular position parameter calibration method of this embodiment includes steps S1-S4.

[0046] In step S1, the rotation and pitch axes of the rotary platform to be calibrated are connected to the coordinate measuring machine, and multiple high-precision positioning standard balls are fixed around the rotary platform to be calibrated. Figure 2 As shown, the high-precision positioning standard spheres are multiple mutually perpendicular high-precision coordinate spheres distributed around the rotating platform. The number of coordinate spheres can be three, four, or more. Figure 2Four coordinate spheres 4, 5, 6, and 7 are shown. A fixture 3 is fixed to the central axis of the rotary platform, and its central axis coincides with the central axis of the rotary platform, used to clamp the components. The high-precision positioning standard sphere is rigidly connected to the rotary platform via a rigid support to ensure that the high-precision positioning standard sphere and the rotation axis 1 and pitch axis 2 of the rotary platform are always in the same coordinate system. The method of this embodiment measures the pose changes of the multiple high-precision positioning standard spheres before and after the rotation axis 1 and pitch axis 2 of the rotary platform using a coordinate measuring machine, calculates the pose changes of the rotation axis 1 and pitch axis 2 of the rotary platform, and thus calibrates the angular position parameters of the rotary platform. The coordinate measuring machine can calibrate the rotary platform before each test of the components.

[0047] In step S2, the high-precision positioning standard sphere is measured using a coordinate measuring machine, and the initial coordinate system when the rotating platform is stationary is calculated and determined.

[0048] In one embodiment, step S2 includes the following steps:

[0049] S21: Zero the pose of the rotating platform, and measure the high-precision positioning standard ball using a coordinate measuring machine to obtain the measurement data of the high-precision positioning standard ball;

[0050] S22: Perform Gaussian fitting (least square fitting) on ​​the measurement data of the high-precision positioning standard sphere to calculate the coordinates of each sphere center point;

[0051] S23: Using the three center points A of the sphere 11 A 12 A 13 The coordinate system of the rotating platform when it is stationary is determined by two vector cross products. The coordinate system matrix corresponding to this coordinate system is [A] 12 -A 11 V calm11 V calm12 ].

[0052] Specifically, with vector (A) 12 -A 11 ) as the X-axis vector, through vector (A) 12 -A 11 ) and vector (A 13 -A 11 The cross product yields the Y-axis vector V. calm11 The Z-axis vector V is obtained by the cross product of the X-axis vector and the Y-axis vector. calm12 ,Right now:

[0053] V calm11 =(A 12 -A11 )×(A 13 -A 11 V calm12 =(A 12 -A 11 )×V calm11 .

[0054] In step S3, the angular position parameters of the rotation axis of the rotating platform are calibrated by utilizing the pose changes of the high-precision positioning standard ball before and after the rotation axis of the rotating platform moves. This calibration is determined by the coordinate system changes of the high-precision positioning standard ball before and after the rotation axis of the rotating platform moves. Specific steps include:

[0055] Step S31: The rotation axis of the rotating platform moves at fixed angular intervals (30° intervals), and the high-precision positioning standard ball is measured after each movement by a coordinate measuring machine to obtain measurement data;

[0056] Step S32: Perform Gaussian fitting (least square fitting) on ​​the high-precision positioning standard ball measurement data to calculate the coordinates of each ball center point;

[0057] Step S33: Using the three center points A of the spheres 21 A 22 A 23 The coordinate system of the rotating platform after its rotation axis motion is determined by two vector cross products. The coordinate system matrix corresponding to this coordinate system is [A] 22 -A 21 V calm21 V calm22 ], where V calm21 =(A 22 -A 21 )×(A 23 -A 21 V calm22 =(A 22 -A 21 )×V calm21 ;

[0058] Step S34: Based on the coordinate system and the coordinate system The transformation matrix for the first coordinate system is calculated as follows:

[0059]

[0060] Wherein, λ1 is the first scaling parameter, R1 is the first rotation parameter, and Δ1 is the first translation vector;

[0061] X1, Y1, Z1 are Point A in the coordinate system 11 A12 A 13 The X, Y, and Z coordinate values;

[0062] X2, Y2, Z2 are Point A in the coordinate system 21 A 22 A 23 The X, Y, and Z coordinate values.

[0063]

[0064] Among them, |A 21 A 22 |Is A 21 A 22 Two points at Distance in a coordinate system;

[0065] |A 11 A 12 |Is A 11 A 12 Two points at Distance in a coordinate system;

[0066] |A 22 A 23 |Is A 22 A 23 Two points at Distance in a coordinate system;

[0067] |A 12 A 13 |Is A 12 A 13 Two points at Distance in a coordinate system;

[0068] |A 23 A 21 |Is A 23 A 21 Two points at Distance in a coordinate system;

[0069] |A 13 A 11 |Is A 13 A 11 Two points at Distance in a coordinate system.

[0070]

[0071] Where I is the identity matrix,

[0072]

[0073] in, A represents 11 A 12 Two points at The difference in Z-axis coordinate values ​​in the coordinate system;

[0074] A represents 21 A 22 Two points at The difference in Z-axis coordinate values ​​in the coordinate system;

[0075] A represents 11 A 12 Two points at The difference in Y-axis coordinate values ​​in the coordinate system;

[0076] A represents 21 A 22 Two points at The difference in Y-axis coordinate values ​​in the coordinate system;

[0077] A represents 11 A 12 Two points at The difference in X-axis coordinate values ​​in the coordinate system;

[0078] A represents 21 A 22 Two points at The difference between the X-axis coordinate values ​​in the coordinate system.

[0079] Substitute the coordinates of any point back into the formula to calculate Δ1. Here, "any point" refers to point A before the motion. 11 Point and corresponding A after the movement 21 Point, or A before movement 12 Point and corresponding A after the movement 22 Point, or A before movement 13 Point and corresponding A after the movement 23 point.

[0080] S35: Based on the calculated coordinate system transformation matrix, the high-precision positioning standard sphere is positioned... The pose quaternion parameters (rotation parameters) in the coordinate system are used to calculate the position of the rotating platform after the rotation axis moves at 30° intervals. The new pose quaternion parameters in the coordinate system are used to calculate the rotation angle, and the angular position parameters of the rotary platform's rotation axis are calibrated. The calibration result for angular position positioning error is generally taken as half the difference between the maximum and minimum errors at each calibration point.

[0081] Step S4: The pitch axis angular position parameters of the rotating platform are calibrated by utilizing the pose change of the high-precision positioning standard ball before and after the pitch axis movement of the rotating platform. This calibration is determined by the coordinate system change of the high-precision positioning standard ball before and after the pitch axis movement of the rotating platform. Specific steps include:

[0082] Step S41: The pitch axis of the rotating platform moves at 30° intervals, and the coordinate measuring machine measures the high-precision positioning standard ball after each rotation to obtain measurement data;

[0083] Step S42: Perform Gaussian fitting (least square fitting) on ​​the measurement data of the high-precision positioning standard sphere to calculate the coordinates of the sphere's center point;

[0084] Step S43: Using the three center points A of the spheres 31 A 32 A 33 The coordinate system of the rotating platform after pitch axis motion is determined by two vector cross products. The coordinate system matrix corresponding to this coordinate system is [A] 32 -A 31 V calm31 V calm32 ], where V calm31 =(A 32 -A 31 )×(A 33 -A 31 V calm32 =(A 32 -A 31 )×V calm31 ;

[0085] Step S44: Based on the coordinate system and the coordinate system The second coordinate transformation matrix is ​​calculated and determined as follows:

[0086]

[0087] Where λ2 is the second proportional parameter, R2 is the second rotation parameter, and Δ2 is the second translation vector;

[0088] X1, Y1, Z1 are Point A in the coordinate system 11 A 12 A 13 The X, Y, and Z coordinate values;

[0089] X3, Y3, Z3 are Point A in the coordinate system 31 A 32 A 33 The X, Y, and Z coordinate values.

[0090]

[0091] Among them, |A 31 A 32 |Is A 31 A 32 Two points at Distance in a coordinate system;

[0092] |A 11 A 12 |Is A 11 A 12 Two points at Distance in a coordinate system;

[0093] |A 32 A 33 |Is A 32 A 33 Two points at Distance in a coordinate system;

[0094] |A 12 A 13 |Is A 12 A 13 Two points at Distance in a coordinate system;

[0095] |A 33 A 31 |Is A 33 A 31 Two points at Distance in a coordinate system;

[0096] |A 13 A 11 |Is A 13 A 11 Two points at Distance in a coordinate system.

[0097]

[0098] Where I is the identity matrix,

[0099]

[0100] in, A represents 11 A 12 Two points at The difference in Z-axis coordinate values ​​in the coordinate system;

[0101] A represents 31 A 32Two points at The difference in Z-axis coordinate values ​​in the coordinate system;

[0102] A represents 11 A 12 Two points at The difference in Y-axis coordinate values ​​in the coordinate system;

[0103] A represents 31 A 32 Two points at The difference in Y-axis coordinate values ​​in the coordinate system;

[0104] A represents 11 A 12 Two points at The difference in X-axis coordinate values ​​in the coordinate system;

[0105] A represents 31 A 32 Two points at The difference between the X-axis coordinate values ​​in the coordinate system.

[0106] Substitute the coordinates of any point back into the formula to calculate Δ2. Here, "any point" refers to point A before the motion. 11 Point and corresponding A after the movement 31 Point, or A before movement 12 Point and corresponding A after the movement 32 Point, or A before movement 13 Point and corresponding A after the movement 33 point.

[0107] Step S45: Based on the calculated second coordinate system transformation matrix, the high-precision positioning standard sphere is positioned... The pose quaternion parameters in the coordinate system are used to calculate the pitch axis of the rotating platform after it moves at 30° intervals. The new pose quaternion parameters in the coordinate system are used to calculate the rotation angle and calibrate the angular position parameters of the pitch axis of the rotating platform.

[0108] The rotary platform angular position parameter calibration method of the above embodiments of the present invention has the following beneficial effects:

[0109] 1. This invention uses coordinate system transformation and the pose change of a high-precision positioning standard ball fixed on a rotating platform to calibrate the angular position parameters of the rotation axis and pitch axis. The calibration method is simple, and coordinate machine operators can calibrate the accuracy of the rotating platform in real time, which helps to improve measurement accuracy.

[0110] 2. This invention utilizes a coordinate measuring machine to calibrate angular position parameters in situ, reducing the use of multifaceted prisms or calibration gratings and improving the calibration efficiency of the measured rotational axis angular position parameters.

[0111] The rotary platform angular position parameter calibration method of the above embodiments of the present invention is applicable to the calibration of rotary axis angular position parameters in a five-axis composite coordinate measuring machine (three axes of coordinate machine plus two axes of rotary table). The five-axis composite coordinate measuring machine is simple to operate for measuring standard ball. Compared with the traditional angular position parameter calibration method, it can complete the calibration in situ, which improves the calibration accuracy and efficiency of angular position parameters.

[0112] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A method for calibrating the pose of a rotating platform, characterized in that, include: Step S1: Connect the rotary platform to be calibrated to the coordinate measuring machine, and fix multiple high-precision positioning standard balls around the rotary platform to be calibrated. Step S2: Measure the high-precision positioning standard sphere using a coordinate measuring machine, and calculate and determine the initial coordinate system when the rotating platform is stationary. There are three high-precision positioning standard spheres. When stationary, the coordinates of the three sphere centers are A, B, C, D, E, F, G ... 11 A 12 A 13 The coordinate system when the rotating platform is stationary The corresponding coordinate system matrix is ,in, , ; Step S3, using the pose change of the high-precision positioning standard ball before and after the rotation axis of the rotating platform moves, calibrate the angular position parameters of the rotation axis of the rotating platform, including: The rotation axis of the rotating platform is moved at fixed angular intervals, and the high-precision positioning standard ball after each movement is measured by a coordinate measuring machine to obtain measurement data; Gaussian fitting was performed on the measurement data of the high-precision positioning standard sphere to calculate the coordinates of each sphere's center point; The coordinate system of the rotating platform after its rotation axis motion is determined based on the coordinates of each sphere's center point. After the rotating shaft moves at fixed angular intervals, the coordinates of the three sphere centers are A, B, C, D, E, F, G ... 21 A 22 A 23 Then the coordinate system after the rotation axis has moved The corresponding coordinate system matrix is ,in, , ; Based on the initial coordinate system Coordinate system after rotation axis motion Calculate and determine the transformation matrix of the first coordinate system; Based on the calculated first coordinate system transformation matrix, the high-precision positioning standard sphere is positioned in the initial coordinate system. The pose parameters are calculated to obtain the position of the rotation axis in the initial coordinate system after moving at fixed angular intervals. The pose parameters are used to calculate the rotation angle, and the angular position parameters of the rotary platform's rotation axis are calibrated. Step S4, using the pose change of the high-precision positioning standard ball before and after the pitch axis movement of the rotating platform, calibrate the pitch axis angular position parameters of the rotating platform, including: The pitch axis of the rotating platform is moved at fixed angular intervals, and the coordinate measuring machine measures the high-precision positioning standard ball after each movement to obtain measurement data; The coordinates of the sphere's center point are calculated by fitting the measurement data of the high-precision positioning standard sphere. Determine the coordinate system of the rotating platform after its pitch axis motion based on the coordinates of each sphere's center point. After the pitch axis moves at fixed angular intervals, the coordinates of the three sphere centers are A, B, C, D, E, F, G ... 31 A 32 A 33， The coordinate system after pitch axis motion The corresponding coordinate system matrix is ​​as follows ,in, , ; Based on the initial coordinate system coordinate system after pitch axis motion Calculate and determine the transformation matrix of the second coordinate system; Based on the calculated second coordinate system transformation matrix, the high-precision positioning standard sphere is positioned in the initial coordinate system. The pose parameters are calculated to obtain the pitch axis position in the initial coordinate system after moving at fixed angular intervals. The pose parameters are used to calculate the rotation angle, and the angular position parameters of the pitch axis of the rotating platform are calibrated.

2. The method according to claim 1, characterized in that, Step S2 includes: The pose of the rotating platform is zeroed, and the high-precision positioning standard ball is measured by a coordinate measuring machine to obtain the measurement data of the high-precision positioning standard ball. Gaussian fitting was performed on the measurement data of the high-precision positioning standard sphere to calculate the coordinates of each sphere's center point; Determine the coordinate system of the rotating platform when it is stationary based on the coordinates of each sphere's center point. .

3. The method according to claim 2, characterized in that, In step S3, the transformation matrix of the first coordinate system is: , Where λ1 is the first scaling parameter, R1 is the first rotation parameter, and Δ1 is the first translation vector. These are the first translation vectors. exist X , Y , Z Components along the axial direction; X1, Y1, and Z1 are the initial coordinate system. Point A below 11 A 12 A 13 of X , Y , Z Coordinate values; X2, Y2, and Z2 are the coordinate systems after the rotation axis has moved. Point A below 21 A 22 A 23 of X , Y , Z Coordinate values.

4. The method according to claim 3, characterized in that, In step S4, the second coordinate transformation matrix is: , Where λ2 is the second proportional parameter, R2 is the second rotation parameter, and Δ2 is the second translation vector. The second translation vectors are respectively exist X , Y , Z Components along the axial direction; X1, Y1, and Z1 are the initial coordinate system. Point A below 11 A 12 A 13 of X , Y , Z Coordinate values; X3, Y3, and Z3 are the coordinate systems after pitch axis motion. Point A below 31 A 32 A 33 of X , Y , Z Coordinate values.

5. The method according to any one of claims 1 to 4, characterized in that, The fixed angle interval is 30°.

6. The method according to any one of claims 1 to 4, characterized in that, In step S1, the high-precision positioning standard ball is rigidly connected to the rotating platform through a rigid support to ensure that the high-precision positioning standard ball and the rotation axis and pitch axis of the rotating platform are always in the same coordinate system.

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