A flat-bottomed cylindrical probe in-machine calibration method, device and equipment

Abstract

This invention relates to the field of stylus calibration technology, and discloses an in-machine calibration method, apparatus, and equipment for a flat-bottomed cylindrical stylus. The method includes: modeling the flat-bottomed cylindrical stylus to be calibrated and a ring gauge; obtaining the model of the flat-bottomed cylindrical stylus to be calibrated and the model of the ring gauge; generating a radius calibration measurement path and a length calibration measurement path; placing the ring gauge on the machine table; obtaining the measurement origin using a reference tool; running the flat-bottomed cylindrical stylus to be calibrated along the calibration measurement path to obtain the corresponding set of measured points; using the least squares circle fitting principle, fitting all measured points in the radius measured point set into a circle; obtaining the equivalent diameter of the calibrated flat-bottomed cylindrical stylus based on the fitted circle center and the fitted radius; using the average Z-axis coordinate of all measured points in the length measured point set as the length deviation to compensate for the actual length of the flat-bottomed cylindrical stylus to be calibrated, obtaining the calibration length; and completing the calibration of the flat-bottomed cylindrical stylus based on the equivalent diameter and the calibration length.

Description

Technical Field

[0001] This invention relates to the field of probe calibration technology, and in particular to an in-machine calibration method, apparatus and equipment for a flat-bottomed cylindrical probe. Background Technology

[0002] As is well known, the probe is an important component of a measurement system. Its operating principle is as follows: when measuring a part, the probe contacts the workpiece, causing displacement of the internal structure of the probe head, which in turn generates a relevant signal from the internal sensor. After receiving the signal, the motion controller of the CNC machine tool sends the current coordinates to the measurement software. The software then uses this coordinate data, combined with the probe radius and the normal of the contact point, to obtain accurate coordinate values.

[0003] However, errors can occur during the actual production and assembly of the probe, leading to deviations in its length and diameter. After installation on the probe head, its actual position and shape may differ from the probe head model. Wear during use can also cause inaccurate diameter measurements. In actual measurement work, different lengths, shapes, and diameters of probes may need to be selected based on the shape and size of the workpiece being measured. Therefore, considering the aforementioned displacement during triggering, the actual radius of the probe, and installation errors, the actual radius of the probe needs to be calibrated to ensure accurate measurement with different probe configurations. Furthermore, due to spindle thermal expansion, the probe length is inherently unstable and constantly changing, necessitating correction of the probe's tool length before measurement.

[0004] There are two main methods for calibrating flat-bottomed cylindrical probes on CNC machine tools: built-in calibration macro programs in the CNC system and Renishaw probe calibration macro programs. Built-in calibration macro programs are typically written for specific machine tool models and configurations, with relatively fixed parameter settings, making it difficult to flexibly adjust them according to different measurement tasks and workpiece requirements. While Renishaw probe calibration macro programs offer relatively rich measurement functions to a certain extent, their functionality remains limited for some complex measurement tasks, such as surface measurement and measurement of non-standard shaped workpieces. Furthermore, different versions of CNC systems may have varying levels of support for macro programs; some new functions and instructions may not be available in older systems. Since machine measurement software usually needs to be compatible with different versions of CNC systems, built-in calibration macro programs may not function correctly or may produce inaccurate results on some CNC systems. Renishaw probes come in various models and software versions, and compatibility issues exist between them; if the probe model used does not match the calibration macro program, or the software version is inconsistent, calibration failures or inaccurate measurement results may occur.

[0005] In summary, both calibration methods described above have their own applicable scope and usage: the built-in macro program of the CNC system is suitable for the machine tool's built-in measurement methods, while the Renishaw probe calibration program is suitable for Renishaw macro program programming. However, in-machine measurement software has its own compensation methods, and directly using the calibration results from the two methods may lead to inaccurate measurement results due to incompatibility. Furthermore, different CNC systems have different built-in calibration and compensation methods, resulting in poor versatility. If the built-in macro program calibration and compensation method of the CNC system is used, the in-machine measurement software becomes more complex and difficult to use, making it difficult to promote and apply to different machine tools. The complex operation also leads to errors in the calibration results. Therefore, while the two methods are fine for simple origin centering and alignment, they are not flexible enough for in-machine measurement software, produce inconsistent calibration results, and have poor versatility. Summary of the Invention

[0006] Therefore, the technical problem to be solved by the present invention is to overcome the problems that the calibration method of flat-bottomed cylindrical probe in the prior art is not applicable to in-machine measurement software, is inflexible, has low accuracy, and has poor versatility.

[0007] To solve the above-mentioned technical problems, the present invention provides an in-machine calibration method for a flat-bottomed cylindrical probe, comprising:

[0008] Model the flat-bottomed cylindrical probe and the ring gauge to be calibrated, and obtain the model of the flat-bottomed cylindrical probe and the model of the ring gauge.

[0009] Based on the flat-bottomed cylindrical probe model and the ring gauge model, the measurement path of the inner circle group of the ring gauge is obtained as the radius calibration measurement path, and the measurement path of the upper end face group of the ring gauge is obtained as the length calibration measurement path.

[0010] Place the ring gauge on the machine table and use the reference tool to obtain the measurement origin;

[0011] Starting from the measurement origin, the flat-bottomed cylindrical probe to be calibrated is made to run along the radius calibration measurement path. The relative coordinate values ​​of the flat-bottomed cylindrical probe to be calibrated are obtained each time it is triggered during the operation, and a set of radius measurement points is constructed.

[0012] Using the least squares method for circle fitting, all measured points in the set of measured radius points are fitted into a circle, and the center and radius of the fitted circle are obtained.

[0013] Based on the diameter and fitting radius of the ring gauge, the equivalent diameter of the flat-bottomed cylindrical probe to be calibrated is obtained.

[0014] Starting from the measurement origin, the flat-bottomed cylindrical probe to be calibrated is made to run along the length calibration measurement path. The relative coordinate values ​​of the flat-bottomed cylindrical probe to be calibrated are obtained each time it is triggered during the operation, and a set of actual length measurement points is constructed.

[0015] The average value of the Z-axis coordinates of all measured points in the set of measured length points is used as the length deviation of the flat-bottomed cylindrical probe to be calibrated. The actual length of the flat-bottomed cylindrical probe to be calibrated is then compensated to obtain the calibration length.

[0016] The calibration of the flat-bottomed cylindrical probe is completed based on its equivalent diameter and calibration length.

[0017] Preferably, 3D CAM is used to model the flat-bottomed cylindrical probe and the ring gauge to be calibrated, obtain the model of the flat-bottomed cylindrical probe and the ring gauge, and generate the measurement path of the inner circle group and the measurement path of the upper end group of the ring gauge.

[0018] Preferably, the ring gauge is placed on the machine table, and the measurement origin is obtained using a reference tool, including:

[0019] Make the reference tool perpendicular to the top of the ring gauge, and obtain the current position height of the reference tool, which is the Z-axis coordinate of the measurement origin;

[0020] Use the reference tool to obtain the center point of the ring gauge, and use the horizontal and vertical coordinates of the ring gauge center point as the X-axis and Y-axis coordinates of the measurement origin.

[0021] Preferably, using the least squares circle fitting principle, all measured points in the set of measured radius points are fitted into a circle, including:

[0022] The parametric equation of the fitted circle is defined as follows: ;

[0023] Based on the measured points in the set of radius measurement points, an error function is constructed, expressed as: ;

[0024] Using gradient descent, obtain the parameters at which the error function converges. , and Substituting these values ​​into the parametric equation of the fitted circle, we obtain the expression for the target fitted circle, which is: ;

[0025] in, , and These represent the th radius in the set of measured points. The X-axis and Y-axis coordinates of each measured point , This represents the total number of measured points in the set of measured radius points.

[0026] Preferably, obtaining the center and radius of the fitted circle includes:

[0027] Obtain the center of the fitted circle The value can be: ;

[0028] Obtain the fitting radius of the fitted circle , is represented as: .

[0029] Preferably, based on the diameter of the ring gauge and the fitted radius, the equivalent diameter of the flat-bottomed cylindrical probe to be calibrated is obtained, expressed as:

[0030] ;

[0031] in, This indicates the equivalent diameter of the flat-bottomed cylindrical probe to be calibrated. Indicates the diameter of the ring gauge. This represents the fitted radius.

[0032] Preferably, the average value of the Z-axis coordinates of all measured points in the set of measured length points is taken as the length deviation of the flat-bottomed cylindrical probe to be calibrated, expressed as:

[0033] ;

[0034] in, This indicates the length deviation of the flat-bottomed cylindrical probe to be calibrated. In the set of measured length points, the first... Z-axis coordinates of the measured points , This represents the total number of measured points in the set of measured length points.

[0035] Preferably, the actual length of the flat-bottomed cylindrical probe to be calibrated is added to the length deviation to obtain the calibration length of the flat-bottomed cylindrical probe to be calibrated, which is expressed as:

[0036] ;

[0037] in, This indicates the calibration length of the flat-bottomed cylindrical probe to be calibrated. This indicates the actual length of the flat-bottomed cylindrical probe to be calibrated.

[0038] This embodiment also provides a calibration device based on the on-machine calibration method for flat-bottomed cylindrical styluses as described above, including:

[0039] The model building module is used to model the flat-bottomed cylindrical probe and the ring gauge to be calibrated, and to obtain the model of the flat-bottomed cylindrical probe and the ring gauge.

[0040] The path generation module is used to obtain the inner circle group measurement path of the ring gauge as the radius calibration measurement path and the upper end face group measurement path of the ring gauge as the length calibration measurement path, based on the flat-bottomed cylindrical probe model to be calibrated and the ring gauge model.

[0041] The origin acquisition module is used to place the ring gauge on the machine table and acquire the measurement origin using a reference tool;

[0042] The equivalent diameter calculation module is used to run the flat-bottomed cylindrical probe to be calibrated along the radius calibration measurement path, starting from the measurement origin. It obtains the relative coordinate values ​​of the flat-bottomed cylindrical probe to be calibrated each time it is triggered during the operation, and constructs a set of radius measurement points. Using the least squares circle fitting principle, it fits all the measurement points in the radius measurement point set into a circle and obtains the fitting circle's center and fitting radius. Based on the diameter of the ring gauge and the fitting radius, it obtains the equivalent diameter of the flat-bottomed cylindrical probe to be calibrated.

[0043] The calibration length calculation module is used to run the flat-bottomed cylindrical probe to be calibrated along the length calibration measurement path, starting from the measurement origin. It obtains the relative coordinate value of the flat-bottomed cylindrical probe to be calibrated each time it is triggered during the operation, and constructs a set of actual length measurement points. The average value of the Z-axis coordinates of all actual length measurement points in the set of actual length measurement points is used as the length deviation of the flat-bottomed cylindrical probe to be calibrated, and the actual length of the flat-bottomed cylindrical probe to be calibrated is compensated to obtain the calibration length.

[0044] The calibration module is used to calibrate the flat-bottomed cylindrical probe to be calibrated based on its equivalent diameter and calibration length.

[0045] This embodiment also provides an in-machine calibration device for a flat-bottomed cylindrical probe, including:

[0046] machine tool;

[0047] The flat-bottomed cylindrical probe to be calibrated is installed on the preset probe of the machine tool;

[0048] A ring gauge is placed on the machine table surface;

[0049] The on-machine calibration device for the flat-bottomed cylindrical probe described above is connected to the machine tool so that the equivalent diameter and calibration length of the flat-bottomed cylindrical probe to be calibrated can be obtained by using the machine tool, and the flat-bottomed cylindrical probe to be calibrated can be calibrated.

[0050] Compared with the prior art, the above-described technical solution of the present invention has the following advantages:

[0051] The on-machine calibration method for flat-bottomed cylindrical probes described in this invention utilizes on-machine measurement on a machine tool, combined with a precision gauge such as a ring gauge. The flat-bottomed cylindrical probe to be calibrated travels along a generated calibration path to acquire corresponding measured points. The equivalent diameter and length deviations of the probe are then directly calculated for calibration. This invention, by performing calibration directly on the machine tool through on-machine measurement, avoids errors introduced during production, assembly, and use of the probe. It also eliminates reliance on traditional machine tool calibration methods, requiring only calculations based on the collected measured points to obtain the corresponding calibration data. This significantly reduces the risks associated with data interaction with the machine tool, simplifies the process for machine tool operators, improves the accuracy of measurement results, ensures calibration accuracy, and ultimately enhances the precision of flat-bottomed cylindrical probe products. Furthermore, different CNC systems can adopt the calibration and compensation methods of this invention, and the software calibration programming method is the same, thus solving the problem of software universality. Attached Figure Description

[0052] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein:

[0053] Figure 1 This is a flowchart of the in-machine calibration method for the flat-bottomed cylindrical probe provided by the present invention;

[0054] Figure 2 A schematic diagram of a flat-bottomed cylindrical probe;

[0055] Figure 3 This is a schematic diagram of a ring gauge;

[0056] Figure 4 This is a schematic diagram of the measurement path for the inner circle group of the ring gauge;

[0057] Figure 5 This is a schematic diagram of the measurement path for the upper end face assembly of the ring gauge;

[0058] Figure 6 This is a flowchart of the calibration process for the flat-bottomed cylindrical probe in QJCAM provided by the present invention;

[0059] Figure 7 This is a schematic diagram of a flat-bottomed cylindrical probe model;

[0060] Figure 8 This is a schematic diagram of a toroidal scale;

[0061] Figure 9 This is a schematic diagram of the probe calibration module provided by the present invention;

[0062] Figure 10 This is a schematic diagram of the measurement path provided by the present invention;

[0063] Figure 11 This is a schematic diagram of placing a ring gauge on the machine table provided by the present invention;

[0064] Figure 12 This is a schematic diagram of the calibration results of the flat-bottomed cylindrical probe provided by the present invention;

[0065] Figure 13 This is a schematic diagram of the detection results of each measurement point after calibration provided by the present invention. Detailed Implementation

[0066] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0067] Reference Figure 1 The flowchart shown illustrates the steps of the on-machine calibration method for the flat-bottomed cylindrical probe provided by this invention. The specific steps include:

[0068] S101: Model the flat-bottomed cylindrical probe and ring gauge to be calibrated, and obtain the model of the flat-bottomed cylindrical probe and the ring gauge.

[0069] S102: Based on the flat-bottomed cylindrical probe model and the ring gauge model to be calibrated, the inner circle surface group measurement path of the ring gauge is obtained as the radius calibration measurement path, and the upper end surface group measurement path of the ring gauge is obtained as the length calibration measurement path.

[0070] S103: Place the ring gauge on the machine table and use the reference tool to obtain the measurement origin, including:

[0071] Make the reference tool perpendicular to the top of the ring gauge, and obtain the current position height of the reference tool, which is the Z-axis coordinate of the measurement origin;

[0072] Use the reference tool to obtain the center point of the ring gauge, and use the horizontal and vertical coordinates of the ring gauge center point as the X-axis and Y-axis coordinates of the measurement origin.

[0073] S104: Starting from the measurement origin, let the flat-bottomed cylindrical probe to be calibrated run along the radius calibration measurement path, obtain the relative coordinate value of each time the flat-bottomed cylindrical probe to be calibrated is triggered during the operation, and construct a set of radius measurement points.

[0074] S105: Using the least squares method for circle fitting, fit all the measured points in the set of radius measured points into a circle, and obtain the center and radius of the fitted circle.

[0075] S106: Based on the diameter and fitting radius of the ring gauge, obtain the equivalent diameter of the flat-bottomed cylindrical probe to be calibrated, expressed as:

[0076] ;

[0077] in, This indicates the equivalent diameter of the flat-bottomed cylindrical probe to be calibrated. Indicates the diameter of the ring gauge. This represents the fitted radius.

[0078] S107: Starting from the measurement origin, let the flat-bottomed cylindrical probe to be calibrated run along the length calibration measurement path, obtain the relative coordinate value when the flat-bottomed cylindrical probe to be calibrated is triggered each time during the operation, and construct a set of actual length measurement points;

[0079] S108: The average value of the Z-axis coordinates of all measured points in the set of measured length points is used as the length deviation of the flat-bottomed cylindrical probe to be calibrated. The actual length of the flat-bottomed cylindrical probe to be calibrated is then compensated to obtain the calibration length.

[0080] S109: Based on the equivalent diameter and calibration length of the flat-bottomed cylindrical probe to be calibrated, complete the calibration of the flat-bottomed cylindrical probe to be calibrated.

[0081] Reference Figure 2 The image shown is a schematic diagram of a flat-bottomed cylindrical probe; refer to... Figure 3 The diagram shown is a schematic of a ring gauge; refer to... Figure 4 The diagram shown is a schematic of the measurement path for the inner circle group of the ring gauge; refer to... Figure 5 The diagram shows the measurement path of the upper end face group of the ring gauge. Specifically, in this embodiment, 3D CAM is used to model the flat-bottomed cylindrical probe to be calibrated and the ring gauge, obtain the model of the flat-bottomed cylindrical probe to be calibrated and the model of the ring gauge, and generate the measurement path of the inner circle group and the measurement path of the upper end face group of the ring gauge.

[0082] Specifically, in step S105, the least squares circle fitting principle is used to fit all measured points in the radius measurement point set into a circle, and the center and radius of the fitted circle are obtained, including:

[0083] S105-1: Define the parametric equation of the fitted circle as follows: ;

[0084] S105-2: Constructing an error function based on the measured points in the set of measured radius points. , is represented as: ;

[0085] S105-3: Using gradient descent, obtain the parameters at which the error function converges. , and Substituting these values ​​into the parametric equation of the fitted circle, we obtain the expression for the target fitted circle, which is: ;

[0086] in, , and These represent the th radius in the set of measured points. The X-axis and Y-axis coordinates of each measured point , This represents the total number of measured points in the set of measured radius points.

[0087] S105-4: Obtain the center of the fitted circle. The value can be: ;

[0088] S105-5: Obtain the fitting radius of the fitted circle , is represented as: .

[0089] Specifically, in step S108, the average value of the Z-axis coordinates of all measured points in the set of measured length points is used as the length deviation of the flat-bottomed cylindrical probe to be calibrated. The actual length of the flat-bottomed cylindrical probe to be calibrated is then compensated to obtain the calibration length, including:

[0090] S108-1: The average value of the Z-axis coordinates of all measured points in the set of measured length points is taken as the length deviation of the flat-bottomed cylindrical probe to be calibrated. , is represented as:

[0091] ;

[0092] in, In the set of measured length points, the first... Z-axis coordinates of the measured points , This represents the total number of measured points in the set of measured length points.

[0093] S108-2: Compensate for the actual length of the flat-bottomed cylindrical probe to be calibrated to obtain the calibration length. , is represented as:

[0094] ;

[0095] in, This indicates the actual length of the flat-bottomed cylindrical probe to be calibrated.

[0096] The on-machine calibration method for flat-bottomed cylindrical probes described in this invention utilizes on-machine measurement on a machine tool, combined with a precision gauge such as a ring gauge. The flat-bottomed cylindrical probe to be calibrated travels along a generated calibration path to acquire corresponding measured points. The equivalent diameter and length deviations of the probe are then directly calculated for calibration. This invention, by performing calibration directly on the machine tool through on-machine measurement, avoids errors introduced during production, assembly, and use of the probe. It also eliminates reliance on traditional machine tool calibration methods, requiring only calculations based on the collected measured points to obtain the corresponding calibration data. This significantly reduces the risks associated with data interaction with the machine tool, simplifies the process for machine tool operators, improves the accuracy of measurement results, ensures calibration accuracy, and ultimately enhances the precision of flat-bottomed cylindrical probe products. Furthermore, different CNC systems can adopt the calibration and compensation methods of this invention, and the software calibration programming method is the same, thus solving the problem of software universality.

[0097] Based on the above embodiments, in this embodiment of the invention, the on-machine calibration method for the flat-bottomed cylindrical probe is implemented using the domestically developed industrial software QJCAM as a platform. This embodiment utilizes a Hammer C22 five-axis machine as the experimental machine tool, a Renishaw 400 probe and a D6 cylindrical probe, and a ring gauge with an inner diameter of D49.994. At the machine tool end, the center XYZ of the ring gauge is located using a standard tool and set as the G54 origin. Then, the cylindrical probe is externally tool-set, and the tool length is input into the tool table. On the software side, the probe model is first built in the QJCAM software, the probe calibration module is selected, and the ring gauge model is built within it. A ring gauge calibration measurement group is added, and the machine tool type is selected as a milling machine. The measurement is started, and the probe calibration results are obtained. (Refer to...) Figure 6 The diagram shown is a flowchart for the calibration of the flat-bottomed cylindrical probe in QJCAM. The specific steps include:

[0098] S201: Construct a flat-bottomed cylindrical probe model and a ring-shaped probe model in QJCAM software;

[0099] Reference Figure 7 The image shown is a schematic diagram of a flat-bottomed cylindrical probe model; refer to... Figure 8 The figure shown is a schematic diagram of the toroidal shape;

[0100] S202: Select the probe calibration module, set the ring gauge, and select the corresponding probe. Based on the probe and ring gauge type, the radius calibration measurement path and length calibration measurement path will be automatically generated.

[0101] Reference Figure 9 The diagram shown is a schematic of the probe calibration module; refer to... Figure 10The diagram shows the measurement path; the length calibration measurement path is the upper end face group measurement path, which is used to calibrate the length of the flat-bottomed cylindrical probe; the radius calibration measurement path is the inner circle face group measurement path, which is used to calibrate the radius of the flat-bottomed cylindrical probe.

[0102] S203: After placing the ring gauge on the machine table, use a reference tool to align the center of the ring gauge and set it as the origin of the measurement program, including:

[0103] Use the reference tool to lightly touch the top of the ring gauge, and set the current position as the z of the origin G54;

[0104] Use the reference tool to find the center of the ring gauge and set it as the xy of the origin G54;

[0105] Reference Figure 11 The diagram shown is a schematic of placing the ring gauge on the machine table.

[0106] S204: Start the QJCAM measurement module and automatically send the ring gauge measurement program to the CNC system. The machine tool will automatically execute the program. After the program is completed, the measurement results will be sent back to the QJCAM software so that the QJCAM software can calibrate the probe radius based on the measurement results.

[0107] Reference Figure 12 The image shown is a schematic diagram of the calibration results for the flat-bottomed cylindrical probe; refer to... Figure 13 The diagram shown is a schematic of the detection results at each measurement point after calibration.

[0108] Specifically, after the measurement module is started, the software first converts the measurement path into a measurement macro program recognizable by the CNC system through the corresponding machine tool's post-processing. This macro program is then sent to the machine tool via a network cable, and the machine tool executes it. During the execution of this measurement program, each time the probe is triggered, it records the relative coordinate values ​​(x1, y1, z1), (x2, y2, z2), etc., at the current trigger point and stores these data in the relevant "xxxx.txt" file containing the measured points. After the measurement is completed, "xxxx.txt" is sent back to the QJCAM software for processing. The software and machine tool are connected via a network cable, enabling data transmission and reception.

[0109] ① The radius calibration data processing procedure includes:

[0110] Using the least squares method for circle fitting, multiple measured points are fitted into a circle, and the center and radius of the circle are obtained.

[0111] Least squares analysis is a mathematical optimization technique that finds the best function fit for a set of data by minimizing the sum of squared errors. It uses the simplest method to find the true values ​​of some absolutely unknown data while minimizing the sum of the squared errors.

[0112] Based on the previously measured coordinates of the blade tip (x1, y1, z1), (x2, y2, z2), ..., fit these points to a circle to obtain the radius R, and given the diameter D of the ring gauge, the equivalent diameter D1 of the probe can be obtained using the formula D1 = D - 2 * R.

[0113] ② The length calibration data processing procedure includes:

[0114] Formula for calculating length deviation: ;

[0115] This deviation will be compensated for in the existing tool length. .

[0116] This completes the probe calibration; the entire process can be automated with iterative measurements, ensuring the accuracy of the calibration results.

[0117] This embodiment uses a calibration method for flat-bottomed cylindrical styluses based on QJCAM's in-machine measurement. By employing in-machine measurement techniques combined with precision gauges like ring gauges, it avoids errors arising from stylus production, assembly, and installation. This allows for the accurate determination of the actual radius R and XY eccentricity of the flat-bottomed cylindrical stylus, achieving 2D calibration compensation technology for the stylus on the CNC machine tool. This improves the measurement accuracy of the flat-bottomed cylindrical stylus during machine use, meeting product measurement accuracy requirements. The in-machine measurement software includes a built-in stylus calibration program, eliminating reliance on machine tool calibration methods. This significantly reduces the risks associated with data interaction with the machine tool, facilitating machine operators. Furthermore, it improves the accuracy of measurement results, ensuring the accuracy of the in-machine measurement software. Simultaneously, QJCAM, as a purely domestically developed software, possesses fully independent and controllable intellectual property rights. The simple operation process, high-precision calibration compensation, and stable and reliable software algorithms promote the widespread and in-depth application of in-machine measurement.

[0118] Based on the above embodiments, this invention also provides an in-machine calibration device for a flat-bottomed cylindrical probe, comprising:

[0119] The model building module is used to model the flat-bottomed cylindrical probe and the ring gauge to be calibrated, and to obtain the model of the flat-bottomed cylindrical probe and the ring gauge.

[0120] The path generation module is used to obtain the inner circle group measurement path of the ring gauge as the radius calibration measurement path and the upper end face group measurement path of the ring gauge as the length calibration measurement path, based on the flat-bottomed cylindrical probe model to be calibrated and the ring gauge model.

[0121] The origin acquisition module is used to place the ring gauge on the machine table and acquire the measurement origin using a reference tool;

[0122] The equivalent diameter calculation module is used to run the flat-bottomed cylindrical probe to be calibrated along the radius calibration measurement path, starting from the measurement origin. It obtains the relative coordinate values ​​of the flat-bottomed cylindrical probe to be calibrated each time it is triggered during the operation, and constructs a set of radius measurement points. Using the least squares circle fitting principle, it fits all the measurement points in the radius measurement point set into a circle and obtains the fitting circle's center and fitting radius. Based on the diameter of the ring gauge and the fitting radius, it obtains the equivalent diameter of the flat-bottomed cylindrical probe to be calibrated.

[0123] The calibration length calculation module is used to run the flat-bottomed cylindrical probe to be calibrated along the length calibration measurement path, starting from the measurement origin. It obtains the relative coordinate value of the flat-bottomed cylindrical probe to be calibrated each time it is triggered during the operation, and constructs a set of actual length measurement points. The average value of the Z-axis coordinates of all actual length measurement points in the set of actual length measurement points is used as the length deviation of the flat-bottomed cylindrical probe to be calibrated, and the actual length of the flat-bottomed cylindrical probe to be calibrated is compensated to obtain the calibration length.

[0124] The calibration module is used to calibrate the flat-bottomed cylindrical probe to be calibrated based on its equivalent diameter and calibration length.

[0125] The flat-bottomed cylindrical stylus on-machine calibration device of this embodiment is used to implement the aforementioned flat-bottomed cylindrical stylus on-machine calibration method. Therefore, the specific implementation of the flat-bottomed cylindrical stylus on-machine calibration device can be found in the embodiment section of the flat-bottomed cylindrical stylus on-machine calibration method above. For example, the model construction module, path generation module, and origin acquisition module are used to implement steps S101, S102, and S103 in the above-mentioned flat-bottomed cylindrical stylus on-machine calibration method, respectively; the equivalent diameter calculation module is used to implement steps S104, S105, and S106 in the above-mentioned flat-bottomed cylindrical stylus on-machine calibration method; the calibration length calculation module is used to implement steps S107 and S108 in the above-mentioned flat-bottomed cylindrical stylus on-machine calibration method; and the calibration module is used to implement step S109 in the above-mentioned flat-bottomed cylindrical stylus on-machine calibration method. Therefore, its specific implementation can be referred to the description of the corresponding embodiments, and will not be repeated here.

[0126] Based on the above embodiments, this invention also provides an in-machine calibration device for a flat-bottomed cylindrical probe, comprising:

[0127] machine tool;

[0128] The flat-bottomed cylindrical probe to be calibrated is installed on the preset probe of the machine tool;

[0129] A ring gauge is placed on the machine table surface;

[0130] The on-machine calibration device for the flat-bottomed cylindrical probe described above is connected to the machine tool so that the equivalent diameter and calibration length of the flat-bottomed cylindrical probe to be calibrated can be obtained by using the machine tool, and the flat-bottomed cylindrical probe to be calibrated can be calibrated.

[0131] The on-machine calibration method for flat-bottomed cylindrical probes described in this invention utilizes on-machine measurement on a machine tool, combined with a precision gauge such as a ring gauge. The flat-bottomed cylindrical probe to be calibrated travels along a generated calibration path to acquire corresponding measured points. The equivalent diameter and length deviations of the probe are then directly calculated for calibration. This invention, by performing calibration directly on the machine tool through on-machine measurement, avoids errors introduced during production, assembly, and use of the probe. It also eliminates reliance on traditional machine tool calibration methods, requiring only calculations based on the collected measured points to obtain the corresponding calibration data. This significantly reduces the risks associated with data interaction with the machine tool, simplifies the process for machine tool operators, improves the accuracy of measurement results, ensures calibration accuracy, and ultimately enhances the precision of flat-bottomed cylindrical probe products. Furthermore, different CNC systems can adopt the calibration and compensation methods of this invention, and the software calibration programming method is the same, thus solving the problem of software universality.

[0132] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied 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.

[0133] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. 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 apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1A device that provides the functions specified in one or more boxes.

[0134] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function 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.

[0135] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable 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.

[0136] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for in-machine calibration of a flat-ended cylindrical stylus, characterized by, The method comprises the following steps: Modeling the to-be-calibrated flat-bottom cylindrical measuring pin and the ring gauge to obtain a to-be-calibrated flat-bottom cylindrical measuring pin model and a ring gauge model; Based on the to-be-calibrated flat-bottom cylindrical measuring pin model and the ring gauge model, obtaining an inner circular surface group measurement path of the ring gauge as a radius calibration measurement path and an upper end surface group measurement path of the ring gauge as a length calibration measurement path; Placing the ring gauge on the machine table and obtaining the measurement origin by using the reference knife; Taking the measurement origin as the starting point, making the to-be-calibrated flat-bottom cylindrical measuring pin run along the radius calibration measurement path, obtaining the relative coordinate value of the to-be-calibrated flat-bottom cylindrical measuring pin each time it is triggered during the running process, and constructing a radius actual measurement point set; Using the least square circle fitting principle, fitting all the actual measurement points in the radius actual measurement point set into a circle, and obtaining the fitting center and the fitting radius of the fitted circle; Based on the diameter of the ring gauge and the fitting radius, obtaining the equivalent diameter of the to-be-calibrated flat-bottom cylindrical measuring pin; Taking the measurement origin as the starting point, making the to-be-calibrated flat-bottom cylindrical measuring pin run along the length calibration measurement path, obtaining the relative coordinate value of the to-be-calibrated flat-bottom cylindrical measuring pin each time it is triggered during the running process, and constructing a length actual measurement point set; Taking the average value of the Z-axis coordinates of all the actual measurement points in the length actual measurement point set as the length deviation of the to-be-calibrated flat-bottom cylindrical measuring pin, compensating the actual length of the to-be-calibrated flat-bottom cylindrical measuring pin, and obtaining the calibrated length; Based on the equivalent diameter and the calibrated length of the to-be-calibrated flat-bottom cylindrical measuring pin, completing the calibration of the to-be-calibrated flat-bottom cylindrical measuring pin.

2. The flat-ended cylindrical stylus in-machine calibration method of claim 1, wherein, Modeling the to-be-calibrated flat-bottom cylindrical measuring pin and the ring gauge by using three-dimensional CAM to obtain a to-be-calibrated flat-bottom cylindrical measuring pin model and a ring gauge model, and generating an inner circular surface group measurement path and an upper end surface group measurement path of the ring gauge.

3. The flat-ended cylindrical stylus in-machine calibration method of claim 1, wherein, Placing the ring gauge on the machine table and obtaining the measurement origin by using the reference knife, comprising: Making the reference knife vertically touch the top of the ring gauge, obtaining the current position height of the reference knife as the Z-axis coordinate of the measurement origin; Using the reference knife to obtain the center point of the ring gauge, and taking the horizontal and vertical coordinates of the center point of the ring gauge as the X-axis coordinate and the Y-axis coordinate of the measurement origin.

4. The flat-ended cylindrical stylus in-machine calibration method of claim 1, wherein, Using the least square circle fitting principle, fitting all the actual measurement points in the radius actual measurement point set into a circle, comprising: The parametric equation of the fitting circle is defined as: ; Based on the measured points in the radius measured point set, an error function is constructed and expressed as: ; Using gradient descent method, the parameters are obtained when the error function converges , and , the parameter equation of the fitting circle is obtained, and the target fitting circle expression is ; wherein, , and respectively represent the X-axis coordinate and the Y-axis coordinate of the i-th measured point in the radius measured point set, , , represents the total number of measured points in the radius measured point set.

5. The in-machine calibration method of a flat-ended cylindrical stylus according to claim 4, wherein, Obtaining the fitting center and the fitting radius of the fitted circle, comprising: obtaining a fitting circle center of the fitting circle , taking values as: ; acquiring a fitting radius of the fitted circle is expressed as: .

6. The flat-ended cylindrical stylus in-machine calibration method of claim 1, wherein, Based on the diameter of the ring gauge and the fitting radius, obtaining the equivalent diameter of the to-be-calibrated flat-bottom cylindrical measuring pin, which is represented as: ； wherein, D represents the equivalent diameter of the flat-bottomed cylindrical probe to be calibrated, D represents the diameter of the ring gauge, D represents the fitted radius.

7. The flat-ended cylindrical stylus in-machine calibration method of claim 1, wherein, Taking the average value of the Z-axis coordinates of all the actual measurement points in the length actual measurement point set as the length deviation of the to-be-calibrated flat-bottom cylindrical measuring pin, which is represented as: ； wherein, represents the length deviation of the flat-bottom cylindrical probe to be calibrated, represents the Z-axis coordinate of the th measured point in the length measured point set, , represents the total number of measured points in the length measured point set.

8. The in-situ calibration method of a flat-ended cylindrical stylus according to claim 7, wherein, Adding the actual length of the to-be-calibrated flat-bottom cylindrical measuring pin and the length deviation to obtain the calibrated length of the to-be-calibrated flat-bottom cylindrical measuring pin, which is represented as: ； wherein, denotes the calibration length of the flat-bottomed cylindrical probe to be calibrated, denotes the actual length of the flat-bottomed cylindrical probe to be calibrated.

9. A calibration device for in-machine calibration based on the flat-ended cylindrical stylus according to any one of claims 1 to 8, characterized in that Comprising: A model construction module for modeling the to-be-calibrated flat-bottom cylindrical measuring pin and the ring gauge to obtain a to-be-calibrated flat-bottom cylindrical measuring pin model and a ring gauge model; A path generation module for obtaining an inner circular surface group measurement path of the ring gauge as a radius calibration measurement path and an upper end surface group measurement path of the ring gauge as a length calibration measurement path based on the to-be-calibrated flat-bottom cylindrical measuring pin model and the ring gauge model; An origin acquisition module for placing the ring gauge on the machine table and obtaining the measurement origin by using the reference knife; An equivalent diameter calculation module is configured to, starting from a measurement origin, make the to-be-calibrated flat-bottom cylindrical probe run along a radius calibration measurement path, obtain relative coordinate values when the to-be-calibrated flat-bottom cylindrical probe is triggered during the running, and construct a radius measured point set; the least square circle fitting principle is used to fit all measured points in the radius measured point set into a circle, and a fitting circle center and a fitting radius of the fitting circle are obtained; based on a diameter of the ring gauge and the fitting radius, an equivalent diameter of the to-be-calibrated flat-bottom cylindrical probe is obtained; A calibration length calculation module is configured to, starting from a measurement origin, make the to-be-calibrated flat-bottom cylindrical probe run along a length calibration measurement path, obtain relative coordinate values when the to-be-calibrated flat-bottom cylindrical probe is triggered during the running, and construct a length measured point set; the average value of Z-axis coordinates of all measured points in the length measured point set is taken as a length deviation of the to-be-calibrated flat-bottom cylindrical probe, the actual length of the to-be-calibrated flat-bottom cylindrical probe is compensated, and a calibration length is obtained. A calibration module is configured to complete calibration of the to-be-calibrated flat-bottom cylindrical probe based on the equivalent diameter and the calibration length of the to-be-calibrated flat-bottom cylindrical probe.

10. A flat-bottomed cylindrical probe calibration device, characterized in that, The device comprises: a machine tool; a to-be-calibrated flat-bottom cylindrical probe installed on a preset probe head of the machine tool; a ring gauge placed on a machine table top; The flat-bottom cylindrical probe in machine calibration device according to claim 9 is in communication connection with the machine tool, so as to obtain the equivalent diameter and the calibration length of the to-be-calibrated flat-bottom cylindrical probe by using the machine tool, and calibrate the to-be-calibrated flat-bottom cylindrical probe.

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