A method for identifying and correcting the installation error of a cycloid gear based on a one-dimensional probe

Abstract

The present invention belongs to the technical field of cycloidal gears, and particularly relates to a method for identifying and correcting the installation error of a cycloidal gear based on a one-dimensional probe. According to the precise measurement theory of cycloidal gears, the present invention establishes a measurement coordinate system based on a gear measuring center to determine the measurement reference; uses a one-dimensional probe to touch and take points on the upper / lower end faces of the cycloidal gear, and obtains the tilting attitude of the cycloidal gear through fitting and regression processing of the measurement points; uses a one-dimensional probe to touch and take points on the outer circle of the cycloidal gear, and processes the discrete coordinate data to obtain the eccentric attitude of the cycloidal gear; constructs a corresponding coordinate transformation matrix according to the different poses of the cycloidal gear in the measurement coordinate system, and corrects the measurement results. This method takes into account the influence of the special tooth profile of the cycloidal gear and the motion characteristics of the one-dimensional probe on the measurement, and also takes into account the influence of the installation position of the cycloidal gear in the gear measuring center on the measurement results, and can perform precise tooth profile measurement on the cycloidal gear when there is an installation error, and accurately evaluate its machining accuracy and tooth profile error.

Description

Technical Field

[0001] The present invention belongs to the technical field of cycloidal gears, and particularly relates to a method for identifying and correcting the installation error of a cycloidal gear based on a one-dimensional probe. Background Art

[0002] The cycloidal gear is one of the key components in a high-precision robot RV (Rotate Vector) reducer, and its precision is crucial for influencing the performance of the RV reducer such as motion precision and service life. At present, significant progress has been made in the design and precision machining technology of cycloidal gears in China, and the machining of cycloidal gears shows the characteristics of high precision and high efficiency. Nowadays, most domestic cycloidal gears are detected by a one-dimensional probe gear measuring center. After years of research, although there is still a gap compared with foreign competitors, the precision index of the one-dimensional probe gear measuring center has caught up with the foreign advanced level and can meet most measurement requirements.

[0003] Affected by manual installation and the equipment itself, the cycloidal gear will have varying degrees of eccentricity and inclination during installation. This installation error has a high impact on accurately obtaining the tooth profile data of the cycloidal gear when using a one-dimensional probe gear measuring center for measurement. At the same time, compared with foreign precision gear measuring centers, the one-dimensional probe gear measuring center has low measurement efficiency and unsatisfactory measurement results. One important factor is that the one-dimensional probe has high requirements for the installation and fixation precision during measurement, resulting in frequent installation errors. It is necessary to manually adjust the error situation and measure repeatedly, which affects the measurement efficiency and measurement precision. Foreign research on precision gear measurement technology started earlier and has taken the lead in the technology of identifying and correcting installation errors, forming a technical barrier. Now, foreign high-end gear precision measuring centers have high detection precision and the function of accurately correcting installation errors, while the one-dimensional probe gear measuring center cannot meet the market requirements for the effect of identifying and correcting installation errors. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for identifying the installation error of a cycloidal gear based on a one-dimensional probe to solve the problem of poor identification effect of the installation error of the cycloidal gear in the prior art. The purpose of the present invention is also to provide a method for correcting the installation error of a cycloidal gear based on a one-dimensional probe to solve the problem of poor correction effect of the installation error of the cycloidal gear in the prior art.

[0005] To solve the above technical problems, the present invention provides a method for identifying the installation error of a cycloid gear based on a one-dimensional probe, including an installation tilt error identification method and / or an installation eccentricity error identification method; the installation tilt error identification method includes: controlling the one-dimensional probe of the gear measuring center to touch and mark the upper end face / lower end face of the cycloid gear, and determining the normal vector of the plane where each measurement point is located according to the positions of the measurement points; comparing the positional relationship between the normal vector and the rotation axis of the gear measuring center: if the normal vector is parallel to the rotation axis, it is determined that the cycloid gear has no installation tilt error, otherwise it is determined that the cycloid gear has an installation tilt error; the installation eccentricity error identification method includes: in the case that the cycloid gear has no installation tilt error, controlling the one-dimensional probe to touch and mark the tooth tip of the cycloid gear, performing fitting processing on each measurement point to fit into a circle to obtain a fitting circle, and extracting the center position of the fitting circle; calculating the distance between the center and the rotation axis: if the distance is 0, it is determined that the cycloid gear has no installation eccentricity error, otherwise it is determined that the cycloid gear has an installation eccentricity error.

[0006] The beneficial effects are as follows: The present invention uses a one-dimensional probe to identify and position the measured cycloid gear. By touching and marking the upper end face / lower end face of the cycloid gear for measurement, the pose information of the cycloid gear is obtained, specifically the normal vector of the upper end face / lower end face. Furthermore, by comparing the inclination between the normal vector and the rotation axis, it can be determined whether the cycloid gear has an installation tilt error; and in the case that the cycloid gear has no installation tilt error, the tooth tip of the cycloid gear is touched and marked for measurement to obtain the pose information of the cycloid gear, specifically the center position of the circle obtained by fitting the measurement points. Furthermore, according to the distance between the center position and the rotation axis, it can be determined whether the cycloid gear has an installation eccentricity error. After accurately identifying the installation error of the cycloid gear, it is convenient to correct the installation error of the cycloid gear subsequently, providing a new approach for precise measurement when the cycloid gear is eccentric, and also providing theoretical and technical support for the accurate evaluation of the tooth profile error and machining accuracy of the cycloid gear.

[0007] Further, in the installation tilt error identification method, the following method is used to determine the normal vector of the plane where each measurement point is located: For n measurement points (x i , y i , z i ), i = 1, 2,..., n, the parameters a1, a2, a3 that minimize are obtained, then the plane where each measurement point is located is z = a1x + a2y + a3, and the normal vector of the plane where each measurement point is located is n1 = (A, B, C), where A, B, C, and D are all parameters characterizing the plane.

[0008] The beneficial effects are as follows: By using the method introduced above, the plane where the upper end face / lower end face of the cycloid gear is located can be quickly and accurately fitted, and then the accurate normal vector of this plane can be obtained.

[0009] Further, in the installation eccentricity error identification method, the following method is used to determine the fitting circle: Let the equation of the fitting circle be R 2 =(x - a1) 2 +(y - b1) 2 , where R is the radius of the fitting circle, (a1, b1) is the center of the fitting circle, and let the parameters a, b, c be a = -2a1, b = -2b1, For m measurement points (x j , y j ), j = 1, 2,..., m, let the distance from the measurement point to the center of the fitting circle be d j , then there is d j 2 =(x j - a1) 2 +(y j - b1) 2 , let δ i = d j 2 - R 2 , find the parameters a, b, c that minimize , and thus the equation of the fitting circle x 2 + y 2 + ax + by + c = 0 can be obtained.

[0010] The beneficial effect is that by using the method introduced above, the equation of the fitting circle can be quickly and accurately fitted.

[0011] Further, when performing touch dotting measurement, each measurement point is a measurement point in the measurement coordinate system O0X0Y0Z0. The measurement coordinate system O0X0Y0Z0 is as follows: Taking the bottom end of the base rotation center of the gear measuring center as the origin O0; Taking the rotation axis of the gear measuring center as the Z0 axis, and the upward direction of the rotation axis as the positive direction of the Z0 axis; Taking the measurement withdrawal direction of the one-dimensional probe as the positive direction of the Y0 axis; Taking the direction perpendicular to the Y0 axis and the Z0 axis and close to the workpiece column direction as the positive direction of the X0 axis.

[0012] The beneficial effect is that by establishing the measurement coordinate system introduced above and using this measurement coordinate system as a reference for cycloid gear installation error identification, it is convenient for subsequent measurement and calculation.

[0013] To solve the above technical problems, the present invention also provides a cycloid gear installation error correction method based on a one-dimensional probe, including an installation tilt error correction method and / or an installation eccentricity error correction method;

[0014] The installation tilt error correction method includes: If there is an installation tilt error in the cycloid gear, when measuring with a gear measuring center, based on the coordinate data of each measurement point in the measurement coordinate system O0X0Y0Z0, and the mapping relationship between the coordinate data in the actual coordinate system O2X2Y2Z2 of the second workpiece and the coordinate data in the measurement coordinate system O0X0Y0Z0, determine the coordinate data of each measurement point in the actual coordinate system O2X2Y2Z2 of the second workpiece, so as to obtain the corrected result of the tooth profile of the gear profile; where, the measurement coordinate system O0X0Y0Z0 is: with the bottom end of the base rotation center of the gear measuring center as the origin, the rotation axis of the gear measuring center as the Z0 axis, the measurement withdrawal direction of the one-dimensional probe of the gear measuring center as the Y0 axis, and the axis perpendicular to the Y0 axis and the Z0 axis as the X0 axis; the actual coordinate system O2X2Y2Z2 of the second workpiece is: control the one-dimensional probe of the gear measuring center to touch and mark the upper / lower end face of the cycloid gear, perform fitting processing on each measurement point to fit into an inclined plane to obtain the fitted inclined plane, control the one-dimensional probe to touch and mark the outer circle of the cycloid gear, perform fitting processing on each measurement point to fit into an ellipse to obtain the fitted ellipse, extract the center position of the fitted ellipse, draw a parallel line to the Z0 axis through the center position of the fitted ellipse, and the intersection point of this parallel line and the fitted inclined plane is the origin; with the normal vector direction of the fitted inclined plane as the Z2 axis, the directions of the X2 axis and the Y2 axis are parallel to the projections of the X0 axis and the Y0 axis on the fitted inclined plane;

[0015] The installation eccentricity error correction method includes: If there is no installation tilt error in the cycloid gear and there is an installation eccentricity error, when measuring with a gear measuring center, based on the coordinate data of each measurement point in the measurement coordinate system O0X0Y0Z0, and the mapping relationship between the coordinate data in the actual coordinate system O1X1Y1Z1 of the first workpiece and the coordinate data in the measurement coordinate system O0X0Y0Z0, determine the coordinate data of each measurement point in the actual coordinate system O1X1Y1Z1 of the first workpiece, so as to obtain the corrected result of the tooth profile of the gear profile; where, the actual coordinate system O1X1Y1Z1 of the first workpiece is: control the one-dimensional probe to touch and mark the tooth top of the cycloid gear, perform fitting processing on each measurement point to fit into a circle to obtain the fitted circle, and use the center of the fitted circle as the origin; the X1 axis, Y1, and Z1 axes are respectively parallel to the X0 axis, Y0 axis, and Z0 axis of the measurement coordinate system O0X0Y0Z0.

[0016] The beneficial effects are as follows: When installing and correcting the tilt of the cycloid gear, the actual coordinate system of the second workpiece is established. By using the coordinate transformation relationship between the actual coordinate system of the second workpiece and the measurement coordinate system, the correction of the installation tilt of the cycloid gear can be realized, achieving the purpose of accurately evaluating the tooth profile of the cycloid gear. Moreover, when installing and correcting the eccentricity of the cycloid gear, the actual coordinate system of the first workpiece is established. By using the coordinate transformation relationship between the actual coordinate system of the first workpiece and the measurement coordinate system, the correction of the installation eccentricity of the cycloid gear can be realized, achieving the purpose of accurately evaluating the tooth profile of the cycloid gear. The whole method solves the problems of measurement data distortion and inaccurate error evaluation caused by installation tilt and eccentricity when using a one-dimensional probe to measure the machining error of the cycloid gear, and has important engineering significance and practical value for the precision measurement of the cycloid gear, improving the machining accuracy of the cycloid gear, and accurately evaluating the tooth profile of the cycloid gear.

[0017] Further, in the installation tilt error correction method, the mapping relationship between the coordinate data in the actual coordinate system O2X2Y2Z2 of the second workpiece and the coordinate data in the measurement coordinate system O0X0Y0Z0 is as follows:

[0018]

[0019]

[0020]

[0021]

[0022] In the formula, (x 0i , y 0i , z 0i ) are the coordinate data in the measurement coordinate system; (x 2i , y 2i , z 2i ) are the coordinate data in the actual coordinate system of the second workpiece; θ i is the rotation angle of the cycloid gear when measuring the cycloid gear using a gear measuring center; φ2 is the inclination angle of the actual coordinate system of the second workpiece relative to the measurement coordinate system; a2, b2, c2 are the coordinates of the origin of the actual coordinate system of the second workpiece in the measurement coordinate system; α, β, and γ are the inclination angles of the X2 axis, Y2 axis, and Z2 axis in the actual coordinate system of the first workpiece respectively;

[0023] Further, in the installation eccentricity error correction method, the mapping relationship between the coordinate data in the actual coordinate system O1X1Y1Z1 of the first workpiece and the coordinate data in the measurement coordinate system O0X0Y0Z0 is as follows:

[0024]

[0025] In the formula, (x0i , y 0i , z 0i ) are the coordinate data in the measurement coordinate system; (x 1i , y 1i , z 1i ) are the coordinate data in the actual coordinate system of the first workpiece; θ i is the rotation angle of the cycloid gear when measuring the cycloid gear using a gear measuring center; c1 is the coordinate of the origin of the actual coordinate system of the first workpiece on the Z0 axis in the measurement coordinate system; φ1 is the measurement phase angle of the actual coordinate system of the first workpiece relative to the measurement coordinate system; l is the deviation of the origin of the actual coordinate system of the first workpiece from the origin of the measurement coordinate system.

[0026] Further, the following method is adopted to identify the installation tilt error: Compare the positional relationship between the normal vector of the inclined plane and the Z0 axis: If the normal vector is not parallel to the Z0 axis, it is determined that there is an installation tilt error in the cycloid gear.

[0027] Its beneficial effect is: Using the relationship between the normal vector and the Z0 axis can quickly and accurately determine whether there is an installation tilt error in the cycloid gear.

[0028] Further, the following method is adopted to identify the installation eccentricity error: Calculate the distance between the center position of the fitted circle and the Z0 axis: If the distance is not 0, it is determined that there is an installation eccentricity error in the cycloid gear.

[0029] Its beneficial effect is: Using the distance between the center of the fitted circle and the Z0 axis can quickly and accurately determine whether there is an installation eccentricity error in the cycloid gear.

[0030] Further, the following method is adopted to determine the normal vector of the inclined plane: For n measurement points (x i , y i , z i ), i = 1, 2,..., n, find the parameters a1, a2, a3 that minimize Then the inclined plane where each measurement point is located is z = a1x + a2y + a3, and the normal vector of the inclined plane where each measurement point is located is n1 = (A, B, C), A, B, C, D are all parameters characterizing the plane.

[0031] Its beneficial effect is: By using the method described above, the inclined plane can be quickly and accurately fitted, and then the accurate normal vector of the inclined plane can be obtained. Description of the Drawings

[0032] Figure 1 is the flowchart of the method for identifying and correcting the installation error of the cycloid gear based on a one-dimensional probe of the present invention;

[0033] Figure 2It is a schematic diagram of the measurement coordinate system established by the present invention;

[0034] Figure 3 It is a schematic diagram for judging whether the installation is inclined in the present invention;

[0035] Figure 4 It is a schematic diagram for searching the center position of the cycloid gear when the cycloid gear is installed eccentrically in the present invention;

[0036] Figure 5 It is a simplified diagram of the cycloid gear installed obliquely in the present invention;

[0037] Figure 6 It is a simplified diagram of the cycloid gear installed eccentrically in the present invention.

[0038] Wherein, 1 - one-dimensional probe, 2 - cycloid gear, 3 - measuring column, 4 - workpiece column, 5 - rotating shaft. Specific implementation manner

[0039] Based on the precision measurement theory, the present invention first establishes a measurement coordinate system to determine the measurement reference, and then uses a one-dimensional probe to identify and position the measured cycloid gear blank on this basis. By touching and dotting the upper and lower end faces or the outer circle of the cycloid gear, the installation pose of the cycloid gear is obtained, and whether there is eccentricity or inclination is identified. Furthermore, through different installation postures of the cycloid gear, the measurement results are corrected by means of coordinate transformation. The present invention will be described in detail below with reference to the drawings and embodiments.

[0040] Embodiment of the method for correcting the installation error of a cycloid gear based on a one-dimensional probe:

[0041] An embodiment of the method for correcting the installation error of a cycloid gear based on a one-dimensional probe according to the present invention is as Figure 1 shown, and its overall process is as follows:

[0042] Step 1, establish a measurement coordinate system.

[0043] Use the measurement center to measure the cycloid gear. As Figure 2 shown, 1 is the one-dimensional probe, 2 is the cycloid gear, 3 is the measuring column, 4 is the workpiece column, and 5 is the rotating shaft. Taking the base rotation center base of the gear measurement center in the measurement center as the center of the circle, taking the rotating shaft 5 as the Z0 axis, and the upward direction along the rotating shaft 5 as the positive direction of the Z0 axis, taking the measurement withdrawal direction of the one-dimensional probe 1 as the positive direction of the Y0 axis, and the direction close to the workpiece column 4 and perpendicular to the Y0 axis and the Z0 axis as the positive direction of the X axis, establish a measurement coordinate system O0X0Y0Z0.

[0044] Step 2, judge whether the cycloid gear is installed obliquely.

[0045] Control the one-dimensional probe to touch and dot the upper or lower end face of the cycloid gear for measurement, and obtain the coordinates of each measurement point. As Figure 3As shown in the figure, after fitting regression processing, the normal vector n1 of the plane is obtained. Compare and judge the inclination relationship between the normal vector n1 of the plane and the Z0 axis of the measurement coordinate system: If they are parallel, it indicates that there is no installation inclination error, and proceed to step three to continue judging whether the cycloid gear is installed eccentrically; if they are inclined, it is determined that there is an installation inclination situation, and proceed to step four for installation inclination correction.

[0046] Let the plane equation be:

[0047] Ax + By + Cz + D = 0 (C≠0) (1)

[0048] Simplify to:

[0049]

[0050] Let Then there is:

[0051] z = a1x + a2y + a3 (3)

[0052] For the coordinates (x i , y i , z i ) of n (n≥3) measurement points obtained by measurement, fit the plane equation to make Minimum.

[0053] That is, it satisfies:

[0054]

[0055] Solve equation (4) to obtain the parameters a1, a2, a3. Substitute the parameters a1, a2, a3 into equation (2) to obtain the plane equation. The normal vector of the equation is n1 = (A, B, C). Compare the inclination relationship between the normal vector n1 and the Z0 axis of the measurement coordinate system to determine whether the cycloid gear is installed inclined.

[0056] Step three, judge whether the cycloid gear is installed eccentrically.

[0057] If the normal vector n1 is parallel to the Z0 axis of the coordinate system, touch and mark the top of the cycloid gear tooth (outer circle) for measurement. As Figure 4 shown, fit and regress the obtained measurement point coordinate data into a circle, extract the center coordinate O1(a1, b1, c1) of the fitted circle, and calculate the distance l between the center O1 and the Z0 axis. If l is zero, it is determined that there is no installation error for the cycloid gear; if l is not zero, it is determined that there is an installation eccentricity situation, and proceed to step five for installation eccentricity correction.

[0058] Let the equation of the fitted circle be:

[0059] R 2 = (x - a1) 2+(y - b1) 2 (5)

[0060] That is:

[0061] R 2 = x 2 - 2a1x + a1 2 + y 2 - 2b1y + b1 2 (6)

[0062] Let a = -2a1, b = -2b1, then there is The equation of the circle can be expressed as x 2 + y 2 + ax + by + c = 0.

[0063] Ignoring the Z0-axis coordinate, process the measured coordinates of the measurement points (x j , y j ), j = 1, 2,..., m. Let the distance from the measurement point to the center of the fitted circle be d j , then there is d j 2 = (x j - a1) 2 + (y j - b1) 2 Let δ i = d j 2 - R 2 A formula can be constructed Find the parameters a, b, c, and the equation of the fitted circle can be obtained. At this time, the center coordinates are O1(a1, b1, c1), and the distance l from the center of the circle to the Z0-axis of the measurement coordinate system is The angle φ1 is

[0064] Step 4, perform installation tilt correction on the cycloid gear.

[0065] When there is an installation tilt situation, as Figure 5 shown, control the one-dimensional probe to touch and mark the outer circle of the cycloid gear, fit it into an ellipse, extract the center coordinates O1'(a1', b1', c1') of the fitted ellipse, draw a perpendicular line from the center O1' of the ellipse to the XOY plane and intersect the tilted plane fitted in Step 2 at point O2(a2, b2, c2). Based on O2(a2, b2, c2), establish the second workpiece actual coordinate system O2X2Y2Z2, with the positive direction of the Z2-axis along n1 upward, and the X2 and Y2 directions parallel to the projections of X0 and Y0 on the tilted plane. The inclination angle φ2 of the second workpiece actual coordinate system O2X2Y2Z2 relative to the measurement coordinate system O0X0Y0Z0 is

[0066] According to the principle of spatial coordinate transformation, establish the mapping relationship matrices L, M, and N between the actual coordinate system of the workpiece and the theoretical coordinate system of the workpiece under the condition of cycloid gear rotation measurement:

[0067]

[0068]

[0069]

[0070] In the formula, α, β, and γ are the inclination angles of the X2 axis, Y2 axis, and Z2 axis in the actual coordinate system of the second workpiece respectively. Then the mapping relationship between the coordinate data in the actual coordinate system of the second workpiece and the coordinate data in the measurement coordinate system under the measurement state is:

[0071]

[0072] In the formula, θ i is the rotation angle of the cycloid gear when measuring the cycloid gear using a gear measuring center;. Re-fit the converted coordinate data into the cycloid gear profile to obtain the corrected measurement result.

[0073] Step Five, perform installation eccentricity correction on the cycloid gear.

[0074] When there is an eccentricity situation, as Figure 6 shown, establish the actual coordinate system O1X1Y1Z1 of the first workpiece according to the center position O1(a1, b1, c1), eccentricity l, and phase angle φ1 of the circle, and establish the following mapping relationship between the actual coordinate system of the first workpiece and the measurement coordinate system:

[0075]

[0076] In the formula, l is the deviation of the origin of the actual coordinate system of the first workpiece relative to the origin of the measurement coordinate system, It should be noted that the center O1(a1, b1, c1) in this step is different from the center O2(a2, b2, c2) in Step Four. The center O1(a1, b1, c1) in this step is obtained by calculation under the condition of installation eccentricity, and O2(a2, b2, c2) in Step Four is obtained by calculation under the condition of installation inclination.

[0077] Re-fit the converted coordinate data into the cycloid gear profile to obtain the corrected measurement result.

[0078] In summary, the present invention takes into account the influence of the special cycloid gear profile and the motion characteristics of the one-dimensional probe on the measurement, and also considers the influence relationship between the installation position of the cycloid gear on the gear measuring center and the measurement result. When there is an installation error in the cycloid gear, the one-dimensional probe measuring center can be used to perform precise profile measurement on it, so as to accurately evaluate its machining accuracy and profile error, which is of great significance for the precise measurement of cycloid gears, improving the machining accuracy of cycloid gears and realizing the accurate evaluation of cycloid gear profiles.

[0079] Embodiment of the method for identifying the installation error of a cycloid gear based on a one-dimensional probe:

[0080] An embodiment of the method for identifying the installation error of a cycloid gear based on a one-dimensional probe of the present invention has an overall idea of establishing a measurement coordinate system based on the gear measuring center according to the precise measurement theory of cycloid gears to determine the measurement reference; using a one-dimensional probe to touch and take points on the upper or lower end face of the cycloid gear, and obtaining the tilt attitude of the cycloid gear through fitting and regression processing of the discrete measurement point coordinates; using a one-dimensional probe to touch and take points on the outer circle of the cycloid gear, and obtaining the eccentric attitude of the cycloid gear through processing of the discrete measurement point coordinate data. The specific processing process is the same as that of steps one and two in the embodiment of the method for correcting the installation error of a cycloid gear based on a one-dimensional probe. Since the method for identifying the installation error of a cycloid gear has been introduced in detail in the embodiment of the method for correcting the installation error of a cycloid gear based on a one-dimensional probe, this embodiment will not be elaborated.

Claims

1. A method for identifying the installation error of a cycloid gear based on a one-dimensional probe, characterized in that, Including an installation tilt error identification method and / or an installation eccentricity error identification method; The installation tilt error identification method includes: controlling a one-dimensional probe of a gear measuring center to perform touch dotting measurement on the upper end face / lower end face of a cycloid gear, and determining the normal vector of the plane where each measurement point is located based on the positions of the measurement points; comparing the positional relationship between the normal vector and the rotation axis of the gear measuring center: if the normal vector is parallel to the rotation axis, it is determined that there is no installation tilt error for the cycloid gear, otherwise it is determined that there is an installation tilt error for the cycloid gear; The installation eccentricity error identification method includes: in the case where there is no installation tilt error for the cycloid gear, controlling the one-dimensional probe to perform touch dotting measurement on the tooth tip of the cycloid gear, performing fitting processing on each measurement point to fit into a circle to obtain a fitted circle, and extracting the center position of the fitted circle; calculating the distance between the center and the rotation axis: if the distance is 0, it is determined that there is no installation eccentricity error for the cycloid gear, otherwise it is determined that there is an installation eccentricity error for the cycloid gear.

2. The cycloid gear installation error identification method based on a one-dimensional probe according to claim 1, characterized in that In the installation tilt error identification method, the following method is used to determine the normal vector of the plane where each measurement point is located: For n measurement points (x i , y i , z i ), where i = 1, 2,..., n, find the parameters a1, a2, a3 that minimize . Then the plane where each measurement point lies is z = a1x + a2y + a3, and the normal vector of the plane where each measurement point lies is n1 = (A, B, C), where A, B, C, and D are all parameters characterizing the plane.

3. The method for identifying the installation error of a cycloid gear based on a one-dimensional probe according to claim 1, wherein In the installation eccentricity error identification method, the following method is used to determine the fitted circle: Let the equation of the fitted circle be R 2 =(x - a1) 2 +(y - b1) 2 , where R is the radius of the fitted circle, (a1, b1) is the center of the fitted circle, and let the parameters a, b, c be a = -2a1, b = -2b1, c = a1 2 +b1 2 -R 2 ; For m measurement points (x j , y j ), j = 1, 2,..., m, let the distance from the measurement point to the center of the fitted circle be d j , then there is d j 2 =(x j -a1) 2 +(y j -b1) 2 , let δ i =d j 2 -R 2 , find the parameters a, b, c that minimize , so as to obtain the equation of the fitted circle x 2 +y 2 +ax + by + c = 0.

4. The method for identifying the installation error of a cycloid gear based on a one-dimensional probe according to any one of claims 1 to 3, characterized in that When performing touch dotting measurement, each measurement point is a measurement point in the measurement coordinate system O0X0Y0Z0, and the measurement coordinate system O0X0Y0Z0 is: taking the bottom end of the base rotation center of the gear measuring center as the origin O0; taking the rotation axis of the gear measuring center as the Z0 axis, and the upward direction of the rotation axis as the positive direction of the Z0 axis; taking the measurement withdrawal direction of the one-dimensional probe as the positive direction of the Y0 axis; taking the direction perpendicular to the Y0 axis and the Z0 axis and close to the workpiece column direction as the positive direction of the X0 axis.

5. A cycloid gear installation error correction method based on a one-dimensional probe, characterized in that Including an installation tilt error correction method and / or an installation eccentricity error correction method; The installation tilt error correction method includes: if there is an installation tilt error for the cycloid gear, then when using the gear measuring center for measurement, based on the coordinate data of each measurement point in the measurement coordinate system O0X0Y0Z0 and the mapping relationship between the coordinate data in the second workpiece actual coordinate system O2X2Y2Z2 and the coordinate data in the measurement coordinate system O0X0Y0Z0, determine the coordinate data of each measurement point in the second workpiece actual coordinate system O2X2Y2Z2 to obtain the result after the tooth profile of the gear is corrected; Among them, the measurement coordinate system O0X0Y0Z0 is as follows: taking the bottom end of the base rotation center of the gear measurement center as the origin, the rotation axis of the gear measurement center as the Z0 axis, the retracting measurement direction of the one-dimensional probe of the gear measurement center as the Y0 axis, and the axis perpendicular to the Y0 axis and the Z0 axis as the X0 axis; the actual coordinate system O2X2Y2Z2 of the second workpiece is as follows: controlling the one-dimensional probe of the gear measurement center to touch and mark the upper end face / lower end face of the cycloid gear, performing fitting processing on each measurement point to fit into an inclined plane to obtain the fitted inclined plane, controlling the one-dimensional probe to touch and mark the outer circle of the cycloid gear, performing fitting processing on each measurement point to fit into an ellipse to obtain the fitted ellipse, extracting the center position of the fitted ellipse, drawing a parallel line to the Z0 axis through the center position of the fitted ellipse, and the intersection point of this parallel line and the fitted inclined plane is the origin; taking the normal vector direction of the fitted inclined plane as the Z2 axis, and the directions of the X2 axis and the Y2 axis are parallel to the projections of the X0 axis and the Y0 axis on the fitted inclined plane; The installation eccentricity error correction method includes: if the cycloid gear has no installation tilt error but has an installation eccentricity error, when using the gear measurement center for measurement, based on the coordinate data of each measurement point in the measurement coordinate system O0X0Y0Z0 and the mapping relationship between the coordinate data in the actual coordinate system O1X1Y1Z1 of the first workpiece and the coordinate data in the measurement coordinate system O0X0Y0Z0, determine the coordinate data of each measurement point in the actual coordinate system O1X1Y1Z1 of the first workpiece to obtain the corrected result of the tooth profile of the gear profile; Among them, the actual coordinate system O1X1Y1Z1 of the first workpiece is as follows: controlling the one-dimensional probe to touch and mark the tooth tip of the cycloid gear, performing fitting processing on each measurement point to fit into a circle to obtain the fitted circle, and taking the center of the fitted circle as the origin; the X1 axis, Y1, and Z1 axes are respectively parallel to the X0 axis, Y0 axis, and Z0 axis of the measurement coordinate system O0X0Y0Z0.

6. The cycloid gear installation error correction method based on a one-dimensional probe according to claim 5, characterized in that In the installation tilt error correction method, the mapping relationship between the coordinate data in the actual coordinate system O2X2Y2Z2 of the second workpiece and the coordinate data in the measurement coordinate system O0X0Y0Z0 is: where (x 0i , y 0i , z 0i ) are the coordinate data in the measurement coordinate system; (x 2i , y 2i , z 2i ) are the coordinate data in the actual coordinate system of the second workpiece; θ i is the rotation angle of the cycloid gear when measuring the cycloid gear using a gear measuring center; φ2 is the inclination angle of the actual coordinate system of the second workpiece relative to the measurement coordinate system; a2, b2, c2 are the coordinates of the origin of the actual coordinate system of the second workpiece in the measurement coordinate system; α, β, and γ are the inclination angles of the X2 axis, Y2 axis, and Z2 axis in the actual coordinate system of the first workpiece respectively; 7. The method for correcting the installation error of a cycloid gear based on a one-dimensional probe according to claim 5, characterized in that In the installation eccentricity error correction method, the mapping relationship between the coordinate data in the actual coordinate system O1X1Y1Z1 of the first workpiece and the coordinate data in the measurement coordinate system O0XObY0Z0 is: where (x 0i , y 0i , z 0i ) are the coordinate data in the measurement coordinate system; (x 1i , y 1i , z 1i ) are the coordinate data in the actual coordinate system of the first workpiece; θ i is the rotation angle of the cycloid gear when measuring the cycloid gear using a gear measuring center; c1 is the coordinate of the origin of the actual coordinate system of the first workpiece on the Z0 axis in the measurement coordinate system; φ1 is the measurement phase angle of the actual coordinate system of the first workpiece relative to the measurement coordinate system; l is the deviation of the origin of the actual coordinate system of the first workpiece from the origin of the measurement coordinate system.

8. The method for correcting the installation error of a cycloid gear based on a one-dimensional probe according to claim 5, wherein The following method is used to identify the installation tilt error: compare the positional relationship between the normal vector of the inclined plane and the Z0 axis: if the normal vector is not parallel to the Z0 axis, it is determined that the cycloid gear has an installation tilt error.

9. The method for correcting the installation error of a cycloid gear based on a one-dimensional probe according to claim 5, characterized in that The following method is used to identify the installation eccentricity error: calculate the distance between the center position of the fitted circle and the Z0 axis: if the distance is not 0, it is determined that the cycloid gear has an installation eccentricity error.

10. The method for correcting the installation error of a cycloid gear based on a one-dimensional probe according to claim 8, characterized in that, The following method is used to determine the normal vector of the inclined plane: For n measurement points (x i , y i , z i ), where i = 1, 2,..., n, the parameters a1, a2, a3 are obtained such that is minimized. Then the inclined plane where each measurement point lies is z = a1x + a2y + a3, and the normal vector of the inclined plane where each measurement point lies is n1 = (A, B, C), where A, B, C, and D are all parameters characterizing the plane.

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