A parameter calibration method and device for a polishing machine

Abstract

The application discloses a parameter calibration method and device for a polishing machine tool, and the method comprises the following steps: acquiring coordinates of a plurality of probe end collision points; performing circle fitting on the coordinates of the plurality of probe end collision points by using a least square method to obtain initial center coordinates and an initial radius; calculating difference data corresponding to the coordinates of the plurality of probe end collision points according to the coordinates of the plurality of probe end collision points, the initial center coordinates and the initial radius; obtaining final center coordinates and a radius until the number of iterations is less than a preset number and the maximum difference data is less than a preset threshold; obtaining a height value of a polishing point relative to the center coordinates; and calculating a rotation axis compensation angle according to the height value and the radius. The application is suitable for occasions where various fitting methods are used to determine calibration parameters, does not need expensive calibration equipment, is simple and easy to operate, has accurate calibration results, is low in cost, can be used for calibrating other types of machine tools, and is high in adaptability.

Description

Technical Field

[0001] This invention relates to the field of machine tool technology, and in particular to a parameter calibration method for a polishing machine tool, a parameter calibration device for a polishing machine tool, a computer device, and a storage medium. Background Technology

[0002] Machine tool calibration parameters are essential for motion transformations, and their accuracy directly affects the precision of trajectory motion control. Therefore, the accuracy of calibration parameters is crucial for CNC systems. There are many methods to obtain machine tool calibration parameters, such as directly obtaining them from machine tool drawings. Obtaining calibration data is simple, but due to some errors that inevitably occur during machine tool assembly, the accuracy of calibration parameters obtained in this way is often insufficient.

[0003] To obtain accurate calibration parameters, specialized measuring instruments are typically used to measure machine tools. For example, Chinese patent number CN201520301298.X discloses a dynamic accuracy calibration method for a five-axis machine tool, which uses a layout of two surface contact dial indicators on a support to avoid the process of solving complex equations and the calculation errors of conventional dial indicators. However, this method requires ensuring that the center axes of the two dial indicators are perpendicular to each other and in the same plane when arranging the dial indicators, making the arrangement of the measuring equipment very complicated.

[0004] Another commonly used method is to use a probe and a calibration ball. The probe is mounted on the spindle, and the calibration ball is mounted on the rotary table. The rotary table is rotated to the measurement point to obtain the dataset, and then the calibration data is obtained directly using the least squares method. This method is only applicable when the measurement data is relatively accurate. If there are individual anomalies in the measured data, the calibration data calculated by this method will deviate significantly from the actual calibration parameters. Calibration data obtained from machine tool drawings often deviates from the actual machine tool data. Using a laser tracker for calibration is complex to install and operate, and the instrument is extremely expensive. Summary of the Invention

[0005] In view of the above problems, embodiments of the present invention are proposed to provide a parameter calibration method for a polishing machine tool, a parameter calibration device for a polishing machine tool, a computer device, and a storage medium to overcome or at least partially solve the above problems.

[0006] To achieve the above objectives, this invention proposes a parameter calibration method for a polishing machine tool, the method comprising:

[0007] The coordinates of multiple probe tip collision points were obtained;

[0008] The coordinates of the collision points at the ends of the multiple probes are fitted to a circle using the least squares method to obtain the initial center coordinates and the initial radius.

[0009] Based on the coordinates of the multiple probe tip collision points, the initial center coordinates, and the initial radius, the difference data corresponding to the coordinates of the multiple probe tip collision points are calculated;

[0010] The difference data is compared with a preset threshold and a preset number of iterations. If the largest difference data is greater than the preset threshold and the number of iterations is less than the preset number of iterations, the largest difference data is scaled along the line connecting the coordinate point and the center of the circle to the arc of the fitted circle. The coordinates of one or more probe tip collision points are updated with preset data points to obtain a new fitted circle.

[0011] Repeat the steps of calculating the difference data corresponding to the coordinates of the multiple probe tip collision points based on the coordinates of the multiple probe tip collision points, the initial center coordinates, and the initial radius; compare the difference data with a preset threshold and a preset number of iterations until the number of iterations is less than the preset number of iterations and the maximum difference data converges to a value less than the preset threshold, to obtain the final center coordinates and radius;

[0012] The height value of the grinding point relative to the center coordinates is obtained, and the rotation axis compensation angle is calculated based on the height value and the radius.

[0013] Preferably, the step of performing circle fitting on the coordinates of the collision points of the plurality of probe ends using the least squares method to obtain the initial center coordinates and initial radius includes:

[0014] Obtain the preset center coordinates and preset radius;

[0015] Establish a distance equation from the coordinates of the collision points of the multiple probe tips to the coordinates of a preset center; wherein, the distance equation includes a first preset parameter and a second preset parameter;

[0016] Establish an equation for the difference between the sum of the squares of the distances from the coordinates of the collision points at the ends of the probes to the edge of the circle and the square of the radius; the difference equation includes the relationship between the first preset parameter, the second preset parameter and the first initial parameter, the second initial parameter and the third initial parameter;

[0017] Establish the sum of squares equation of the difference equation to obtain a system of equations containing the first equation, the second equation, and the third equation; wherein the first equation, the second equation, and the third equation contain the first initial parameter, the second initial parameter, and the third initial parameter;

[0018] Solve the system of equations to obtain the first initial parameter, the second initial parameter, and the third initial parameter. Based on the first initial parameter, the second initial parameter, and the third initial parameter, obtain the initial center coordinates and the initial radius.

[0019] Preferably, the step of calculating the difference data corresponding to the coordinates of the multiple probe tip collision points based on the coordinates of the multiple probe tip collision points, the initial center coordinates, and the initial radius includes:

[0020] Calculate the distance between the coordinates of the multiple probe tip collision points and the initial center coordinates, and calculate the difference between the distance between the coordinates of the multiple probe tip collision points and the initial center coordinates and the initial radius, to obtain the difference data corresponding to the coordinates of the multiple probe tip collision points.

[0021] Preferably, the method includes:

[0022] Obtain the root mean square error of the distance set and the scaling factor of the distance set;

[0023] The product of the root mean square error of the distance set and the scaling factor of the distance set is determined as the preset threshold.

[0024] Preferably, obtaining the root mean square error of the distance set and the scaling factor of the distance set includes:

[0025] Obtain the average value of the difference between the distance from the coordinate point to the center of the circle and the initial radius, and the sum of the distances of all coordinate points whose difference between the distance from the coordinate point to the center of the circle and the initial radius is less than the average value;

[0026] The scaling factor of the distance set is calculated by summing the distances from all coordinate points whose difference from the initial radius is less than the average value and summing the difference data.

[0027] The root mean square error of the distance set is calculated based on the sum of the difference data, the average value of the difference between the distance from the coordinate point to the center of the circle and the initial radius, and the number of coordinate points.

[0028] Preferably, the method includes:

[0029] The difference data is compared with a preset threshold and a preset number of iterations. If the largest difference data is less than the preset threshold and the number of iterations is less than the preset number of iterations, the initial center coordinates and the initial radius are determined as calibration data.

[0030] This invention discloses a parameter calibration device for a polishing machine tool, the device comprising:

[0031] The coordinate acquisition module is used to acquire the coordinates of multiple probe tip collision points;

[0032] The circle fitting module is used to perform circle fitting on the coordinates of the collision points of the multiple probe ends using the least squares method to obtain the initial circle center coordinates and the initial radius.

[0033] The difference data acquisition module is used to calculate the difference data corresponding to the coordinates of the multiple probe tip collision points based on the coordinates of the multiple probe tip collision points, the initial center coordinates, and the initial radius;

[0034] The update module is used to compare the difference data with a preset threshold and a preset number of iterations. If the largest difference data is greater than the preset threshold and the number of iterations is less than the preset number of iterations, the largest difference data is scaled along the line connecting the coordinate point and the center of the circle to the arc of the fitting circle. The coordinates of one or more probe tip collision points are updated with preset data points to obtain a new fitting circle.

[0035] The iteration module is used to repeat the steps of calculating the difference data corresponding to the coordinates of the multiple probe tip collision points based on the coordinates of the multiple probe tip collision points, the initial center coordinates, and the initial radius; comparing the difference data with a preset threshold and a preset number of iterations until the number of iterations is less than the preset number of iterations and the maximum difference data converges to a value less than the preset threshold, thus obtaining the final center coordinates and radius.

[0036] The rotation axis compensation angle acquisition module is used to obtain the height value of the grinding point relative to the center coordinates, and calculate the rotation axis compensation angle based on the height value and the radius.

[0037] Preferably, the circle fitting module includes:

[0038] The first acquisition submodule is used to acquire the preset center coordinates and preset radius;

[0039] The distance equation establishment submodule is used to establish the distance equation from the coordinates of the collision points of the multiple probe tips to the coordinates of a preset center; wherein, the distance equation includes a first preset parameter and a second preset parameter;

[0040] The difference equation establishment submodule is used to establish the difference equation between the sum of the squares of the distances from the coordinates of the collision points of the multiple probe ends to the edge of the circle and the square of the radius; the difference equation includes the relationship between the first preset parameter, the second preset parameter and the first initial parameter, the second initial parameter and the third initial parameter;

[0041] The equation system establishment submodule is used to establish the sum of squares equation of the difference equation, resulting in an equation system containing a first equation, a second equation, and a third equation; wherein the first equation, the second equation, and the third equation contain a first initial parameter, a second initial parameter, and a third initial parameter;

[0042] The solver submodule is used to solve the system of equations to obtain the first initial parameter, the second initial parameter, and the third initial parameter, and to obtain the initial center coordinates and the initial radius based on the first initial parameter, the second initial parameter, and the third initial parameter.

[0043] This invention discloses a computer device, including a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps of the above-described parameter calibration method for a polishing machine tool.

[0044] The present invention discloses a computer-readable storage medium storing a computer program thereon, wherein the computer program, when executed by a processor, implements the steps of the above-described parameter calibration method for a polishing machine tool.

[0045] In this embodiment of the invention, the calibration method for polishing machine tool parameters can still achieve good calibration results even in cases of individual data anomalies, avoiding the influence of abnormal data points. It has universal applicability and is suitable for various fitting methods to determine calibration parameters. It does not require expensive calibration equipment, the method is simple and easy to operate, and the calibration results are accurate and low in cost. It can also be used to calibrate other types of machine tools, demonstrating high adaptability. Attached Figure Description

[0046] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying 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.

[0047] Figure 1 This is a flowchart illustrating the steps of a parameter calibration method for a negative polishing machine tool according to an embodiment of the present invention.

[0048] Figure 2 This is a schematic diagram of a polishing machine tool according to an embodiment of the present invention;

[0049] Figure 3 This is a schematic diagram of the fitted circle before updating data according to an embodiment of the present invention;

[0050] Figure 4 This is a schematic diagram of the fitting circle when updating data according to an embodiment of the present invention;

[0051] Figure 5 This is a schematic diagram of a fitted circle after updating data according to an embodiment of the present invention;

[0052] Figure 6 This is a structural block diagram of an embodiment of a parameter calibration device for a polishing machine tool according to an embodiment of the present invention;

[0053] Figure 7 This is an internal structural diagram of a computer device according to one embodiment. Detailed Implementation

[0054] To make the technical problems, technical solutions, and beneficial effects solved by the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0055] Reference Figure 1 The diagram illustrates a step flowchart of a parameter calibration method for a polishing machine tool according to an embodiment of the present invention, which may specifically include the following steps:

[0056] Step 101: Obtain the coordinates of multiple probe tip collision points;

[0057] In this embodiment of the invention, the polishing machine tool is as follows: Figure 2 As shown, it can be a machine tool including two translation axes and one rotation axis. The X-axis and Z-axis are translation axes, and B is a rotation axis. The rotation center of the rotation axis is the origin of the machine tool coordinate system. The X-axis and Z-axis of the machine tool coordinate system are the movement directions of the translation axis X-axis and the translation axis Z-axis, respectively. The X-axis movement towards the grinding wheel is the positive direction, and the Z-axis movement upward is the positive direction. The origin of the workpiece coordinate system is located at the center of the top of the workpiece, and the axis direction of the workpiece coordinate system is consistent with the axis direction of the machine tool coordinate system.

[0058] Specifically, during the pre-setting process, a trigger-type probe is installed on the top of the workpiece. Further, the probe is calibrated using a lever dial indicator to align the small ball at the probe tip with the central axis of the workpiece, controlling the polishing machine to return to zero and resetting the machine coordinates. In this embodiment, 12 measuring points are set for the B-axis rotary motion, evenly distributed between 0° and 90°. Other preset numbers of measuring points can also be set, such as 24 or 64. This embodiment does not impose excessive limitations on this. The B-axis rotary motion is controlled to move to a certain measuring point, driving the X and Z axes of the machine tool, causing the probe tip to collide with the bottom edge of the grinding wheel. The X and Z movement amounts at the collision point are locked and recorded as coordinates (X...). i Z i ), i∈1,2,...,12, respectively, to obtain the coordinates of the movement of 12 measurement points, that is, to obtain the coordinates of multiple probe tip collision points.

[0059] Step 102: The coordinates of the collision points of the multiple probe ends are fitted to a circle using the least squares method to obtain the initial center coordinates and the initial radius.

[0060] In a preferred embodiment of the present invention, the step of performing circle fitting on the coordinates of the collision points of the plurality of probe ends using the least squares method to obtain the initial center coordinates and the initial radius may include the following sub-steps:

[0061] Sub-step 11: Obtain the preset center coordinates and preset radius;

[0062] In this embodiment of the invention, the preset center coordinates of the fitted circle are set to (A, B), the preset radius of the fitted circle is R, and the curve equation of the fitted circle is: R 2 =(xA) 2 +(zB) 2 ;

[0063] That is, R 2 =x 2 -2Ax+A 2 +z 2 -2Bz+B 2 .

[0064] Sub-step 12: Establish a distance equation from the coordinates of the collision points of the multiple probe ends to the coordinates of the preset center of the circle; wherein, the distance equation includes a first preset parameter and a second preset parameter;

[0065] Specifically, the coordinate set (X) of multiple probe tip collision points i Z i The distance from the midpoint of the circle to the center is d, where i ∈ 1, 2, ..., 12. i ;

[0066]

[0067] Where A is the first preset parameter and B is the second preset parameter.

[0068] Sub-step 13: Establish the difference equation between the sum of the squares of the distances from the coordinates of the collision points of the multiple probe ends to the edge of the circle and the square of the radius; the difference equation includes the relationship between the first preset parameter, the second preset parameter and the first initial parameter, the second initial parameter and the third initial parameter;

[0069] In practical applications, coordinate points (X) i Z i The difference between the sum of the squares of the distances to the edge of the circle and the square of the radius is:

[0070]

[0071] in,

[0072] a = -2A;

[0073] b = -2B;

[0074] c = A 2 +B 2 -R 2 ;

[0075] a is the first initial parameter, b is the second initial parameter, and c is the third initial parameter; the relationship between the first preset parameter A, the second preset parameter B and the first initial parameter a, the second initial parameter b, and the third initial parameter c is as shown above.

[0076] Sub-step 14: Establish the sum of squares equation of the difference equation to obtain a system of equations containing the first equation, the second equation, and the third equation; wherein the first equation, the second equation, and the third equation contain the first initial parameter, the second initial parameter, and the third initial parameter;

[0077] In this embodiment of the invention, coordinate points (X) are established. i Z i The difference δ between the sum of the squares of the distances to the edge of the circle and the square of the radius. i The equation for the sum of squares is Q(a, b, c);

[0078] Specifically, let Q(a, b, c) be the coordinate point (X... i Z i The sum of the squares of the distances to the edge of the circle and the sum of the squares of the difference between the square of the radius and the sum of the squares of the distances to the edge of the circle.

[0079]

[0080] Find the first initial parameter a, the second initial parameter b, and the third initial parameter c that minimize the value of Q(a, b, c). The minimum value can be obtained by comparing the function values ​​at all extreme points.

[0081] First equation:

[0082] Second equation:

[0083] Third equation:

[0084] The equation set consisting of the first equation, the second equation, and the third equation includes the first initial parameter a, the second initial parameter b, and the third initial parameter c.

[0085] Sub-step 15: Solve the system of equations to obtain the first initial parameter a, the second initial parameter b, and the third initial parameter c. Based on the first initial parameter a, the second initial parameter b, and the third initial parameter c, obtain the initial center coordinates and the initial radius.

[0086] Solving the system of equations yields the first initial parameter a, the second initial parameter b, and the third initial parameter c, which in turn allows us to determine the center (A, B) and radius R of the fitted circle. These coordinates are then used as the initial center coordinates (X0, Z0) and the initial radius R0.

[0087] Step 103: Based on the coordinates of the multiple probe tip collision points, the initial center coordinates, and the initial radius, calculate the difference data corresponding to the coordinates of the multiple probe tip collision points;

[0088] In a preferred embodiment of the present invention, the step of calculating the difference data corresponding to the coordinates of the plurality of probe tip collision points based on the coordinates of the plurality of probe tip collision points, the initial center coordinates, and the initial radius includes: calculating the distance between the coordinates of the plurality of probe tip collision points and the initial center coordinates, and calculating the difference between the distance between the coordinates of the plurality of probe tip collision points and the initial center coordinates and the initial radius, thereby obtaining the difference data corresponding to the coordinates of the plurality of probe tip collision points;

[0089] Specifically, each coordinate point (X) can be calculated. i Z i The distance from the initial center coordinates (X0, Z0) to the initial radius R0 is calculated, and then the difference between this distance and the initial radius R0 is calculated to obtain the difference data ΔD corresponding to the coordinates of multiple probe tip collision points. i ,Right now

[0090] Step 104: Compare the difference data with a preset threshold and a preset number of iterations. If the largest difference data is greater than the preset threshold and the number of iterations is less than the preset number of iterations, then scale the largest difference data along the line connecting the coordinate point and the center of the circle to the arc of the fitted circle; update the coordinates of one or more probe tip collision points with preset data points to obtain a new fitted circle.

[0091] In practical application to the embodiments of the present invention, the preset threshold can be the product of the root mean square error σ0 of the distance set and the scaling factor β of the distance set;

[0092] The method in this embodiment of the invention includes: obtaining the root mean square error of the distance set and the scaling factor of the distance set; and determining the product of the root mean square error of the distance set and the scaling factor of the distance set as the preset threshold.

[0093] Further, obtaining the root mean square error of the distance set and the scaling factor of the distance set includes: obtaining the average value of the difference between the distance from the coordinate point to the center of the circle and the initial radius, and the sum of the distances among all coordinate points whose difference between the distance from the center of the circle and the initial radius is less than the average value; calculating the scaling factor of the distance set based on the sum of the distances among all coordinate points whose difference between the distance from the center of the circle and the initial radius is less than the average value and the sum of the difference data; and calculating the root mean square error of the distance set based on the sum of the difference data, the average value of the difference between the distance from the coordinate point to the center of the circle and the initial radius, and the number of coordinate points.

[0094] Specifically, d is the average of the differences between the distances from all coordinate points to the center of the circle and the initial radius R0. i The difference between the distance from all coordinate points to the center of the circle and the initial radius R0 is less than The distance d i The corresponding point is called an interior point, Σd i That is, the sum of the distances between interior points;

[0095] The root mean square error of the distance set And the scaling factor of the distance set The root mean square error σ0 of the distance set is the average of the differences between the distances from all coordinate points to the center of the circle and the initial radius R0. Difference data ΔD i The number of coordinate points n is calculated, and the scaling factor β of the distance set is determined by the difference between the distance from all coordinate points to the center of the circle and the initial radius R0 being less than 1. distance d i The sum and difference data ΔD i The sum is obtained through calculation.

[0096] After obtaining the preset threshold, the difference data ΔD between each coordinate point can be compared. i The largest difference data ΔD i Compared with a preset threshold t, when the largest difference data ΔD i If the difference is greater than a preset threshold t and the number of iterations is less than a preset number n, then the largest difference data is scaled along the line connecting the coordinate point and the center of the circle to the arc of the fitted circle; the coordinates of one or more probe tip collision points are updated with preset data points to obtain a new fitted circle and the coordinates of the new fitted circle probe tip collision points. Figure 3 This is a schematic diagram of the fitted circle before the data was updated. Figure 4 This is a schematic diagram of the fitted circle when updating the data, and Figure 5 This is a schematic diagram of the fitted circle after updating the data;

[0097] The specific process of updating data is as follows: Figure 4 As shown, the difference data ΔD i The largest coordinate point is scaled along the line connecting that point and the center of the circle to the arc of the fitted circle, and the coordinates (X′) are used to represent this. i Z′ i Replace coordinate point (X) i Z i Update data points, used to update the coordinates (X′) of the data. i Z′ i The calculation method for ) is as follows:

[0098]

[0099]

[0100] In another preferred embodiment of the present invention, the method includes: comparing the difference data with a preset threshold and a preset number of iterations; if the largest difference data is less than the preset threshold and the number of iterations is less than the preset number of iterations, the initial center coordinates and the initial radius are determined as calibration data; that is, when the largest difference data is less than the preset threshold and the number of iterations is less than the preset number of iterations, the initial center coordinates are determined as the coordinates of the grinding point of the grinding wheel relative to the rotation center, and the initial radius is determined as the distance from the origin of the workpiece coordinates to the rotation center.

[0101] Step 105: Repeat the steps of calculating the difference data corresponding to the coordinates of the multiple probe tip collision points based on the coordinates of the multiple probe tip collision points, the initial center coordinates, and the initial radius; compare the difference data with a preset threshold and a preset number of iterations until the number of iterations is less than the preset number of iterations and the maximum difference data converges to a value less than the preset threshold, to obtain the final center coordinates and radius.

[0102] In obtaining such Figure 5 After updating the data and creating a new fitted circle, the steps of calculating the difference data, comparing the difference data with a preset threshold, and comparing the difference data with a preset number of times can be repeated until convergence is achieved to the maximum ΔD. i The final center coordinates and radius are obtained when the distance is less than the preset threshold t.

[0103] It should be noted that, based on the method of movement, the final center coordinates are the coordinates of the grinding point of the grinding wheel relative to the center of rotation. Assuming that the origin of the machine tool coordinate system is on the grinding point and the axis direction does not change, the recorded coordinate point data should be negative, and the calculated center coordinate values ​​will have opposite signs. The final center coordinates refer to the position of the center of rotation relative to the grinding point, so the position of the grinding point relative to the center of rotation can be directly negative. After two inversions, the obtained center coordinates are the coordinates of the grinding point relative to the center of rotation. The radius refers to the distance from the origin of the workpiece coordinate system to the center of rotation.

[0104] Step 106: Obtain the height value of the grinding point relative to the center coordinates of the circle, and calculate the rotation axis compensation angle based on the height value and the radius.

[0105] Furthermore, after obtaining the coordinates of the grinding point relative to the rotation center, the rotation axis compensation angle can be calculated. Specifically, the machine tool is controlled to return to zero, and the X and Z axes of the machine tool are driven so that the probe collides with the bottom edge of the grinding wheel. The Z value of the movement is recorded and its absolute value is taken. This Z value is added to the Z value of the grinding point relative to the rotation center, and recorded as the height H of the grinding point relative to the center of the circle. The rotation axis compensation angle is calculated based on the height H and the radius R.

[0106] In this embodiment of the invention, the calibration method for polishing machine tool parameters can still achieve good calibration results even in cases of individual data anomalies, avoiding the influence of abnormal data points. It has universal applicability and is suitable for various fitting methods to determine calibration parameters. It does not require expensive calibration equipment, the method is simple and easy to operate, and the calibration results are accurate. It can also be used to calibrate other types of machine tools, demonstrating high adaptability.

[0107] It should be noted that, for the sake of simplicity, the method embodiments are all described as a series of actions. However, those skilled in the art should understand that the embodiments of the present invention are not limited to the described order of actions, because according to the embodiments of the present invention, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions involved are not necessarily essential to the embodiments of the present invention.

[0108] Reference Figure 6 The diagram shows a structural block diagram of a parameter calibration device for a polishing machine tool according to an embodiment of the present invention, which may specifically include the following modules:

[0109] The coordinate acquisition module 301 is used to acquire the coordinates of multiple probe tip collision points;

[0110] The circle fitting module 302 is used to perform circle fitting on the coordinates of the collision points of the multiple probe ends using the least squares method to obtain the initial circle center coordinates and the initial radius.

[0111] The difference data acquisition module 303 is used to calculate the difference data corresponding to the coordinates of the multiple probe tip collision points based on the coordinates of the multiple probe tip collision points, the initial center coordinates, and the initial radius;

[0112] The update module 304 is used to compare the difference data with a preset threshold and a preset number of iterations. If the largest difference data is greater than the preset threshold and the number of iterations is less than the preset number of iterations, the largest difference data is scaled along the line connecting the coordinate point and the center of the circle to the arc of the fitting circle. The coordinates of one or more probe tip collision points are updated with preset data points to obtain a new fitting circle.

[0113] The iteration module 305 is used to repeat the steps of calculating the difference data corresponding to the coordinates of the multiple probe tip collision points based on the coordinates of the multiple probe tip collision points, the initial center coordinates, and the initial radius; comparing the difference data with a preset threshold and a preset number of iterations, until the number of iterations is less than the preset number of iterations and the maximum difference data converges to a value less than the preset threshold, thus obtaining the final center coordinates and radius.

[0114] The rotation axis compensation angle acquisition module 306 is used to acquire the height value of the grinding point relative to the center coordinates, and calculate the rotation axis compensation angle based on the height value and the radius.

[0115] Preferably, the circle fitting module includes:

[0116] The first acquisition submodule is used to acquire the preset center coordinates and preset radius;

[0117] The distance equation establishment submodule is used to establish the distance equation from the coordinates of the collision points of the multiple probe tips to the coordinates of a preset center; wherein, the distance equation includes a first preset parameter and a second preset parameter;

[0118] The difference equation establishment submodule is used to establish the difference equation between the sum of the squares of the distances from the coordinates of the collision points of the multiple probe ends to the edge of the circle and the square of the radius; the difference equation includes the relationship between the first preset parameter, the second preset parameter and the first initial parameter, the second initial parameter and the third initial parameter;

[0119] The equation system establishment submodule is used to establish the sum of squares equation of the difference equation, resulting in an equation system containing a first equation, a second equation, and a third equation; wherein the first equation, the second equation, and the third equation contain a first initial parameter, a second initial parameter, and a third initial parameter;

[0120] The solver submodule is used to solve the system of equations to obtain the first initial parameter, the second initial parameter, and the third initial parameter, and to obtain the initial center coordinates and the initial radius based on the first initial parameter, the second initial parameter, and the third initial parameter.

[0121] Preferably, the difference data acquisition module includes:

[0122] The calculation submodule is used to calculate the distance between the coordinates of the multiple probe tip collision points and the initial center coordinates, and to calculate the difference between the distance between the coordinates of the multiple probe tip collision points and the initial center coordinates and the initial radius, so as to obtain the difference data corresponding to the coordinates of the multiple probe tip collision points.

[0123] Preferably, the device includes:

[0124] The first acquisition module is used to acquire the root mean square error of the distance set and the scaling factor of the distance set;

[0125] The first determining module is used to determine the product of the root mean square error of the distance set and the scaling factor of the distance set as the preset threshold.

[0126] Preferably, the first acquisition module includes:

[0127] The second acquisition submodule is used to acquire the average value of the difference between the distance from the coordinate point to the center of the circle and the initial radius, and the sum of the distances of all coordinate points whose difference between the distance from the coordinate point to the center of the circle and the initial radius is less than the average value;

[0128] The first calculation submodule is used to calculate the scaling factor of the distance set based on the sum of the distances from all coordinate points whose difference from the initial radius is less than the average value and the sum of the difference data.

[0129] The second calculation submodule is used to calculate the root mean square error of the distance set based on the sum of the difference data, the average value of the difference between the distance from the coordinate point to the center of the circle and the initial radius, and the number of coordinate points.

[0130] Preferably, the device includes:

[0131] The second determining module is used to compare the difference data with a preset threshold and a preset number of iterations. If the largest difference data is less than the preset threshold and the number of iterations is less than the preset number of iterations, the initial center coordinates and the initial radius are determined as calibration data.

[0132] Each module in the parameter calibration device of the aforementioned polishing machine tool can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in the processor of a computer device in hardware form or independent of it, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0133] The parameter calibration device for the polishing machine tool provided above can be used to perform the parameter calibration method for the polishing machine tool provided in any of the above embodiments, and has corresponding functions and beneficial effects.

[0134] In one embodiment, a computer device is provided, which may be a polishing machine tool controller or a polishing machine tool control terminal, and its internal structure diagram may be as follows: Figure 7As shown, the computer device includes a processor, memory, network interface, display screen, and input devices connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The network interface is used to communicate with external terminals via a network connection. When executed by the processor, the computer program implements a parameter calibration method for a polishing machine tool. The display screen can be an LCD screen or an e-ink screen. The input devices can be a touch layer covering the display screen, buttons, a trackball, or a touchpad mounted on the computer device casing, or an external keyboard, touchpad, or mouse.

[0135] Those skilled in the art will understand that Figure 7 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0136] In one embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to perform the following steps:

[0137] The coordinates of multiple probe tip collision points were obtained;

[0138] The coordinates of the collision points at the ends of the multiple probes are fitted to a circle using the least squares method to obtain the initial center coordinates and the initial radius.

[0139] Based on the coordinates of the multiple probe tip collision points, the initial center coordinates, and the initial radius, the difference data corresponding to the coordinates of the multiple probe tip collision points are calculated;

[0140] The difference data is compared with a preset threshold and a preset number of iterations. If the largest difference data is greater than the preset threshold and the number of iterations is less than the preset number of iterations, the largest difference data is scaled along the line connecting the coordinate point and the center of the circle to the arc of the fitted circle. The coordinates of one or more probe tip collision points are updated with preset data points to obtain a new fitted circle.

[0141] Repeat the steps of calculating the difference data corresponding to the coordinates of the multiple probe tip collision points based on the coordinates of the multiple probe tip collision points, the initial center coordinates, and the initial radius; compare the difference data with a preset threshold and a preset number of iterations until the number of iterations is less than the preset number of iterations and the maximum difference data converges to a value less than the preset threshold, to obtain the final center coordinates and radius;

[0142] The height value of the grinding point relative to the center coordinates is obtained, and the rotation axis compensation angle is calculated based on the height value and the radius.

[0143] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, the computer program performing the following steps when executed by a processor:

[0144] The coordinates of multiple probe tip collision points were obtained;

[0145] The coordinates of the collision points at the ends of the multiple probes are fitted to a circle using the least squares method to obtain the initial center coordinates and the initial radius.

[0146] Based on the coordinates of the multiple probe tip collision points, the initial center coordinates, and the initial radius, the difference data corresponding to the coordinates of the multiple probe tip collision points are calculated;

[0147] The difference data is compared with a preset threshold and a preset number of iterations. If the largest difference data is greater than the preset threshold and the number of iterations is less than the preset number of iterations, the largest difference data is scaled along the line connecting the coordinate point and the center of the circle to the arc of the fitted circle. The coordinates of one or more probe tip collision points are updated with preset data points to obtain a new fitted circle.

[0148] Repeat the steps of calculating the difference data corresponding to the coordinates of the multiple probe tip collision points based on the coordinates of the multiple probe tip collision points, the initial center coordinates, and the initial radius; compare the difference data with a preset threshold and a preset number of iterations until the number of iterations is less than the preset number of iterations and the maximum difference data converges to a value less than the preset threshold, to obtain the final center coordinates and radius;

[0149] The height value of the grinding point relative to the center coordinates is obtained, and the rotation axis compensation angle is calculated based on the height value and the radius.

[0150] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0151] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, apparatus, or computer program products. Therefore, embodiments of the present invention can take the form of entirely hardware embodiments, entirely software embodiments, or embodiments combining software and hardware aspects. Furthermore, embodiments of the present invention can take the form of computer program products implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0152] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, terminal devices (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing terminal device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing terminal device, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0153] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing terminal device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0154] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal equipment, causing a series of operational steps to be performed on the computer or other programmable terminal equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable terminal equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0155] Although preferred embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present invention.

[0156] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0157] The present invention has provided a detailed description of a parameter calibration method for a polishing machine tool, a parameter calibration device for a polishing machine tool, a computer device, and a storage medium. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for calibrating parameters of a polishing machine tool, characterized in that, The method includes: The coordinates of multiple probe tip collision points were obtained; The coordinates of the collision points at the ends of the multiple probes are fitted to a circle using the least squares method to obtain the initial center coordinates and the initial radius. Based on the coordinates of the multiple probe tip collision points, the initial center coordinates, and the initial radius, the difference data corresponding to the coordinates of the multiple probe tip collision points are calculated; The difference data is compared with a preset threshold and a preset number of iterations. If the largest difference data is greater than the preset threshold and the number of iterations is less than the preset number of iterations, the largest difference data is scaled along the line connecting the coordinate point and the center of the circle to the arc of the fitting circle. The coordinates of one or more probe tip collision points are updated with preset data points to obtain a new fitting circle. The step of calculating the difference data corresponding to the coordinates of the multiple probe tip collision points based on the coordinates of the multiple probe tip collision points, the initial center coordinates, and the initial radius includes: Calculate the distance between the coordinates of the multiple probe tip collision points and the initial center coordinates, and calculate the difference between the distance between the coordinates of the multiple probe tip collision points and the initial center coordinates and the initial radius, to obtain the difference data corresponding to the coordinates of the multiple probe tip collision points; Obtain the root mean square error of the distance set and the scaling factor of the distance set; The product of the root mean square error of the distance set and the scaling factor of the distance set is determined as the preset threshold. The acquisition of the root mean square error of the distance set and the scaling factor of the distance set includes: Obtain the average value of the difference between the distance from the coordinate point to the center of the circle and the initial radius, and the sum of the distances of all coordinate points whose difference between the distance from the coordinate point to the center of the circle and the initial radius is less than the average value; The scaling factor of the distance set is calculated by summing the distances from all coordinate points whose difference from the initial radius is less than the average value and summing the difference data. The root mean square error of the distance set is calculated based on the sum of the difference data, the average difference between the distance from the coordinate point to the center of the circle and the initial radius, and the number of coordinate points. Repeat the steps of calculating the difference data corresponding to the coordinates of the multiple probe tip collision points based on the coordinates of the multiple probe tip collision points, the initial center coordinates, and the initial radius; compare the difference data with a preset threshold and a preset number of iterations until the number of iterations is less than the preset number of iterations and the maximum difference data converges to a value less than the preset threshold, to obtain the final center coordinates and radius; The height value of the grinding point relative to the center coordinates is obtained, and the rotation axis compensation angle is calculated based on the height value and the radius.

2. The parameter calibration method for a polishing machine tool according to claim 1, characterized in that, The step of fitting the coordinates of the collision points of the multiple probe tips to a circle using the least squares method to obtain the initial center coordinates and initial radius includes: Obtain the preset center coordinates and preset radius; Establish a distance equation from the coordinates of the collision points of the multiple probe tips to the coordinates of a preset center; wherein, the distance equation includes a first preset parameter and a second preset parameter; Establish an equation for the difference between the sum of the squares of the distances from the coordinates of the collision points at the ends of the probes to the edge of the circle and the square of the radius; the difference equation includes the relationship between the first preset parameter, the second preset parameter and the first initial parameter, the second initial parameter and the third initial parameter; Establish the sum of squares equation of the difference equation to obtain a system of equations containing the first equation, the second equation, and the third equation; wherein the first equation, the second equation, and the third equation contain the first initial parameter, the second initial parameter, and the third initial parameter; Solve the system of equations to obtain the first initial parameter, the second initial parameter, and the third initial parameter. Based on the first initial parameter, the second initial parameter, and the third initial parameter, obtain the initial center coordinates and the initial radius.

3. The parameter calibration method for a polishing machine tool according to claim 1, characterized in that, The method includes: The difference data is compared with a preset threshold and a preset number of iterations. If the largest difference data is less than the preset threshold and the number of iterations is less than the preset number of iterations, the initial center coordinates and the initial radius are determined as calibration data.

4. A parameter calibration device for a polishing machine tool, characterized in that, The device includes: The coordinate acquisition module is used to acquire the coordinates of multiple probe tip collision points; The circle fitting module is used to perform circle fitting on the coordinates of the collision points of the multiple probe ends using the least squares method to obtain the initial circle center coordinates and the initial radius. The difference data acquisition module is used to calculate the difference data corresponding to the coordinates of the multiple probe tip collision points based on the coordinates of the multiple probe tip collision points, the initial center coordinates, and the initial radius; The update module is used to compare the difference data with a preset threshold and a preset number of iterations. If the largest difference data is greater than the preset threshold and the number of iterations is less than the preset number of iterations, the largest difference data is scaled along the line connecting the coordinate point and the center of the circle to the arc of the fitting circle. The coordinates of one or more probe tip collision points are updated with preset data points to obtain a new fitting circle. The iteration module is used to repeat the steps of calculating the difference data corresponding to the coordinates of the multiple probe tip collision points based on the coordinates of the multiple probe tip collision points, the initial center coordinates, and the initial radius; comparing the difference data with a preset threshold and a preset number of iterations until the number of iterations is less than the preset number of iterations and the maximum difference data converges to a value less than the preset threshold, thus obtaining the final center coordinates and radius. The step of calculating the difference data corresponding to the coordinates of the multiple probe tip collision points based on the coordinates of the multiple probe tip collision points, the initial center coordinates, and the initial radius includes: Calculate the distance between the coordinates of the multiple probe tip collision points and the initial center coordinates, and calculate the difference between the distance between the coordinates of the multiple probe tip collision points and the initial center coordinates and the initial radius, to obtain the difference data corresponding to the coordinates of the multiple probe tip collision points; Obtain the root mean square error of the distance set and the scaling factor of the distance set; The product of the root mean square error of the distance set and the scaling factor of the distance set is determined as the preset threshold. The acquisition of the root mean square error of the distance set and the scaling factor of the distance set includes: Obtain the average value of the difference between the distance from the coordinate point to the center of the circle and the initial radius, and the sum of the distances of all coordinate points whose difference between the distance to the center of the circle and the initial radius is less than the average value; The scaling factor of the distance set is calculated by summing the distances from all coordinate points whose difference from the initial radius is less than the average value and summing the difference data. The root mean square error of the distance set is calculated based on the sum of the difference data, the average difference between the distance from the coordinate point to the center of the circle and the initial radius, and the number of coordinate points. The rotation axis compensation angle acquisition module is used to obtain the height value of the grinding point relative to the center coordinates, and calculate the rotation axis compensation angle based on the height value and the radius.

5. The parameter calibration device for the polishing machine tool according to claim 4, characterized in that, The circle fitting module includes: The first acquisition submodule is used to acquire the preset center coordinates and preset radius; The distance equation establishment submodule is used to establish the distance equation from the coordinates of the collision points of the multiple probe tips to the coordinates of a preset center; wherein, the distance equation includes a first preset parameter and a second preset parameter; The difference equation establishment submodule is used to establish the difference equation between the sum of the squares of the distances from the coordinates of the collision points of the multiple probe ends to the edge of the circle and the square of the radius; the difference equation includes the relationship between the first preset parameter, the second preset parameter and the first initial parameter, the second initial parameter and the third initial parameter; The equation system establishment submodule is used to establish the sum of squares equation of the difference equation, resulting in an equation system containing a first equation, a second equation, and a third equation; wherein the first equation, the second equation, and the third equation contain a first initial parameter, a second initial parameter, and a third initial parameter; The solver submodule is used to solve the system of equations to obtain the first initial parameter, the second initial parameter, and the third initial parameter, and to obtain the initial center coordinates and the initial radius based on the first initial parameter, the second initial parameter, and the third initial parameter.

6. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the parameter calibration method for the polishing machine tool according to any one of claims 1 to 3.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the parameter calibration method for the polishing machine tool according to any one of claims 1 to 3.

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