Surface machining method of guide rail grinding machine

Abstract

The invention discloses a surface machining method of a guide rail grinding machine, which comprises the following steps of: clamping a workpiece and initializing and calibrating a measuring system and a hydraulic cylinder of the grinding machine to obtain initial surface contour data and a reference temperature value of the workpiece; based on the initial surface contour data and a preset target concave / convex morphology curve, calculating an initial deviation and generating a first-round compensation track file through fitting; a grinding machine hydraulic cylinder is controlled to execute the compensation grinding process based on the first-round compensation track file, off-line contour measurement is conducted after grinding is completed, ground surface contour data are obtained, a residual error curve is calculated, and a secondary compensation track file is generated; the production efficiency is improved, the service life of a machine tool is prolonged, numerical control track compensation is used for replacing machine tool structure adjustment, and repeatable, high-precision and low-abrasion guide rail face middle concave / middle convex machining is achieved.

Description

Technical Field

[0001] This invention relates to the field of machine tool technology, and in particular to a surface processing method for a guideway grinding machine. Background Technology

[0002] Guideway grinding machines are key equipment in high-end CNC machine tool manufacturing, used to process the linear guide mounting surfaces of basic machine tool components (such as saddles, columns, and beams). Their machining accuracy directly affects the straightness, fit accuracy, and overall stability of the machine tool's moving parts. During CNC machine tool assembly, some guideway surfaces require specific concave or convex morphologies to compensate for deformation caused by assembly stress and operating loads, ensuring the machine tool's guiding accuracy and lifespan. With the development of large-scale precision machine tools and automated equipment, how to achieve precise and controllable machining of concave / convex surfaces while maintaining grinding stability has become a widely concerned technical direction in the industry.

[0003] Currently, there are two main traditional methods for machining concave or convex surfaces on guideway grinding machines: First, adjusting the grinding machine feet or guideways to slightly bend the table's trajectory to achieve the desired concave or convex shape; second, using adjustable top blocks or shims under the workpiece to change its clamping state and shape the ground surface. However, both methods have significant limitations. Firstly, frequent adjustments to the grinding machine feet can lead to localized wear and changes in the geometric accuracy of the guideways, increasing maintenance costs and requiring recalibration after each machining operation, resulting in low efficiency. Secondly, adjusting workpiece deformation using top blocks requires consideration of factors such as thermal expansion, clamping force, and elastic recovery, making the machining quality highly dependent on operator experience and difficult to standardize and repeat.

[0004] Based on this, the existing technology has the technical problem that it is impossible to achieve stable and high-precision surface grinding in the concave / convex machining of guideway grinding machines without changing the machine tool structure. Summary of the Invention

[0005] The purpose of this invention is to provide a surface processing method for a guideway grinding machine, thereby solving the above-mentioned technical problems.

[0006] To achieve this objective, the present invention adopts the following technical solution: A surface processing method for a guideway grinding machine includes the following steps: S1, by clamping the workpiece and initializing the measurement system and hydraulic cylinder of the calibrated grinding machine, the initial surface contour data and reference temperature value of the workpiece are obtained; S2, based on the initial surface contour data and the preset target concave / convex topography curve, calculate the initial deviation and generate the first round of compensation trajectory file by fitting; S3. Based on the first round of compensation trajectory file, control the hydraulic cylinder of the grinding machine to perform the compensation grinding process. After the grinding is completed, perform offline contour measurement, obtain the surface contour data after grinding, calculate the residual curve, and generate a secondary compensation trajectory file.

[0007] Optionally, the process of generating the first round of compensation trajectory file specifically includes: smoothing and fitting the initial deviation to generate a compensation amount, then mapping the compensation amount to the target displacement sequence of the hydraulic cylinder through a hydraulic cylinder inverse kinematics model that includes hysteresis and nonlinearity, and generating a trajectory file in the form of a CNC program.

[0008] Optionally, during the compensation grinding process, the temperature data of the workpiece is also collected in real time and recorded together with the actual displacement data of the hydraulic cylinder in the execution log; if the tracking deviation between the actual displacement of the hydraulic cylinder and the target displacement exceeds a preset threshold, real-time adjustment or pause is triggered.

[0009] Optionally, step S1 specifically includes the following steps: S11, clamp the workpiece on the worktable, and use standard gauge blocks and torque wrench to ensure the uniformity of the clamping plane reference and the uniform distribution of clamping force; S12, start the contour measuring instrument and temperature sensor, and use the contour measuring instrument to register the measurement coordinate system with the machine tool coordinate system to obtain the spatial transformation parameters of the measurement system; S13 controls the hydraulic cylinder to perform a low-speed uniform test stroke, collects pressure data through its built-in pressure sensor, fits the hysteresis characteristic curve of the hydraulic cylinder, and calculates the hydraulic cylinder characteristic parameters with respect to nonlinear stiffness from the hysteresis characteristic curve. S14, based on the spatial transformation parameters and hydraulic cylinder characteristic parameters, drive the contour measuring instrument to perform a zero-contact scan on the workpiece surface to obtain the registered initial surface contour data and reference temperature value.

[0010] Optionally, step S3 specifically includes the following steps: S31, load the first round compensation trajectory file into the CNC system, perform a safety check on the hydraulic cylinder's motion range, and generate a verified grinding program; S32, start the grinding program and control the hydraulic cylinder to move along the compensation trajectory; S33, after the grinding process is completed, the control contour measuring instrument performs the first rapid scan on the workpiece surface to obtain preliminary data of the post-grind contour.

[0011] Optionally, step S33 may be followed by: S34. Based on the preliminary data, identify abnormal contour areas, adjust the sampling density of the measuring instrument to perform fine scanning and obtain complete post-grind surface contour data. S35, compare the post-grinding surface contour data with the target morphology curve, and compensate and correct the measurement results by combining the temperature data in the execution log, and calculate the residual curve; S36, the residual curve is smoothed and filtered, a secondary compensation amount is generated based on the preset compensation rules, and mapped to the hydraulic cylinder displacement command to form a secondary compensation trajectory file.

[0012] Optionally, step S3 may further include: S4. Based on the secondary compensation trajectory file, perform iterative correction grinding until the final inspection criteria are met, and archive the processing data during the grinding process to the process library for optimizing the processing of similar workpieces.

[0013] Optionally, the iterative process of the secondary compensation trajectory file is as follows: S41, perform iterative grinding based on the secondary compensation trajectory file, and reacquire the contour data of the workpiece surface after each iteration; S42, compare the contour data obtained after each iteration with the target topography curve, calculate the residual curve for that iteration and determine whether it meets the final inspection criteria; S43. When the final inspection criteria are met, the iteration is automatically terminated and the compensation trajectory sequence and corresponding residual curve of the entire processing of this workpiece are archived to the digital twin process library to generate initial compensation prediction parameters for similar workpieces.

[0014] Optionally, the condition for generating the secondary compensation trajectory file is that the final inspection criterion is met as the termination condition; The final inspection criterion is that the maximum residual of the surface contour data after grinding is less than 0.01 mm or the root mean square value of the contour deviation is less than 0.005 mm.

[0015] Optionally, archived machining data includes the initial profile, compensation trajectory for each round, residual curve, and workpiece temperature data during the compensation grinding process.

[0016] Compared with existing technologies, this invention has the following advantages: This method introduces trajectory compensation based on measured contours at the CNC level to achieve trajectory control of the concave / convex surface morphology of the target, avoiding grinding damage caused by adjusting the machine tool feet or top blocks to obtain the curved surface morphology and the dependence on operating experience; Since the compensation amount is generated by fitting and inverse modeling the measurement data, the grinding process can achieve high smoothness and repeatability, significantly improving machining accuracy and pass rate; In addition, converting residual information into secondary compensation trajectory enables rapid and targeted correction after one machining operation, reducing rework and adjustment time, thereby improving production efficiency and extending machine tool life. By replacing machine tool structure adjustment with CNC trajectory compensation, repeatable, high-precision, and low-wear concave / convex guide surface machining can be achieved. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] The structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0019] Figure 1 This is a schematic diagram of the main process of the surface processing method of the guideway grinding machine in this embodiment. Detailed Implementation

[0020] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0021] In the description of this invention, it should be understood that the terms "upper," "lower," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be a component positioned centrally in the connection.

[0022] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0023] Combination Figure 1 As shown, this embodiment of the invention provides a surface processing method for a guideway grinding machine, including the following steps: S1, by clamping the workpiece and initializing the measurement system and hydraulic cylinder of the calibrated grinding machine, the initial surface contour data and reference temperature value of the workpiece are obtained; Fix the workpiece on the guideway grinding machine table according to the established clamping scheme, ensuring that the clamping torque and support point position are consistent with the process file; then initialize and calibrate the contour measuring instrument, temperature sensor and X-axis hydraulic cylinder, including coordinate system registration, measuring instrument zero point confirmation, sensor offset correction and hydraulic cylinder zero point and gain identification (if necessary, complete the static hysteresis characteristic identification).

[0024] S2, based on the initial surface contour data and the preset target concave / convex topography curve, calculates the initial deviation and generates the first round of compensation trajectory file through fitting.

[0025] Based on the preset target concave or convex topographic curve, the point-by-point deviation is calculated using the initial contour data, and the deviation sequence is denoised and smoothed (e.g., using spline fitting or regularized least squares algorithm) to generate a continuous geometric compensation curve; then the geometric compensation curve is converted into the target displacement sequence of the hydraulic cylinder through the inverse kinematics model, and the first round of compensation trajectory file (CNC macro or interpolation point table) is generated according to the dynamic characteristics of the hydraulic cylinder and the interpolation capability of the CNC system.

[0026] In this process, the nonlinearity, dead zone, and speed / displacement limits of the hydraulic cylinder should be considered, and necessary feedforward or limiting constraints should be added in the generation of the compensation trajectory to ensure that the issued compensation trajectory can be executed smoothly within the controllable range of the CNC system and the hydraulic system. The geometric target is directly coupled with the machine tool's executable control signals to achieve trajectory compensation at the CNC level.

[0027] S3 controls the hydraulic cylinder of the grinding machine to perform the compensation grinding process based on the first round of compensation trajectory file. After the grinding is completed, offline contour measurement is performed to obtain the surface contour data after grinding and calculate the residual curve to generate a secondary compensation trajectory file.

[0028] The initial compensation trajectory file is sent to the CNC system, which then drives the X-axis hydraulic cylinder and the worktable to move along the compensation trajectory and perform grinding. During grinding, the actual displacement of the hydraulic cylinder, online segments of the measuring instrument (if in-process detection is used), and temperature sensor data are recorded for post-grinding analysis. After grinding, a complete offline contour measurement is performed on the workpiece to obtain the post-grind surface contour data, and the residual curve (the difference between the target morphology and the actual morphology) is calculated.

[0029] Statistical and local analysis is performed on the residual curves to remove outliers and smooth the fit. Based on the fitting results, a secondary compensation trajectory file is generated (inverse model correction and execution constraints are also considered when mapping back to the hydraulic cylinder control quantity). This step not only verifies the actual effect of the first round of compensation but also provides a data foundation for subsequent targeted corrections.

[0030] S4. Based on the secondary compensation trajectory file, iteratively correct the grinding until the final inspection criteria are met, and archive the machining data during the grinding process to the process library for optimizing the machining of similar workpieces.

[0031] Iterative grinding correction is performed based on the secondary compensation trajectory file, repeatedly executing the closed-loop process of grinding—measurement—residual analysis—compensation generation until the pre-set final inspection criteria are met (e.g., residuals are within an acceptable range, residual changes tend to stabilize, or the upper limit of the number of iterations is reached). Through iterative closed-loop processing and process archiving, this step helps improve the consistency and repeatability of the machining process and establishes a data foundation for the long-term accumulation and improvement of process parameters.

[0032] The working principle of this invention is as follows: This method introduces trajectory compensation based on measured contours at the CNC level to achieve trajectory control of the concave / convex surface morphology of the target, avoiding grinding damage caused by adjusting the machine tool feet or top blocks to obtain the curved surface morphology and the dependence on operating experience; since the compensation amount is generated by fitting and inverse modeling the measurement data, the grinding process can achieve high smoothness and repeatability, significantly improving machining accuracy and pass rate; in addition, converting the residual information into a secondary compensation trajectory allows for rapid and targeted correction after one machining operation, reducing the number of rework operations and adjustment time, thereby improving production efficiency and extending the service life of the machine tool. By replacing machine tool structure adjustment with CNC trajectory compensation, repeatable, high-precision, and low-wear concave / convex guideway surface machining can be achieved.

[0033] In this embodiment, the process of generating the first round of compensation trajectory file specifically includes: smoothing the initial deviation to generate a compensation amount, and then mapping the compensation amount to the target displacement sequence of the hydraulic cylinder through a hydraulic cylinder inverse kinematics model that includes hysteresis and nonlinearity, and generating a trajectory file in the form of a CNC program.

[0034] It should be noted that, for the initial deviation sequence, the deviation data is first denoised and smoothed to obtain a continuous geometric compensation amount without high-frequency noise; then, the geometric compensation amount is input into the inverse kinematic model that includes the hysteresis and nonlinear characteristics of the hydraulic cylinder, and mapped to the target displacement sequence required by the hydraulic cylinder; the measurement-based geometric compensation amount is reliably converted into control commands that can be executed and are safe in the machine tool and hydraulic system.

[0035] In this embodiment, it is further explained that during the compensation grinding process, the temperature data of the workpiece is collected in real time and recorded together with the actual displacement data of the hydraulic cylinder in the execution log; if the tracking deviation between the actual displacement of the hydraulic cylinder and the target displacement exceeds a preset threshold, real-time adjustment or pause is triggered.

[0036] It should be noted that during grinding using the initial compensation trajectory file, the system simultaneously collects and records real-time data on the workpiece surface, ambient temperature, and the actual displacement (and pressure) of the hydraulic cylinder. All time series data are written to the execution log for subsequent correlation analysis. The system calculates the tracking deviation between the target displacement and the actual displacement in real time and compares the deviation with a preset threshold. If the tracking deviation exceeds the threshold, the system can trigger a real-time response according to a preset strategy (e.g., triggering feedforward correction, reducing the feed rate, temporarily reverting to a safe position, or automatically pausing the program and issuing an alarm) to prevent abnormal grinding and reduce error accumulation.

[0037] In this embodiment, step S1 specifically includes the following steps: S11, clamp the workpiece on the worktable, and use standard gauge blocks and torque wrenches to ensure that the reference of the clamping plane is consistent and the clamping force is evenly distributed.

[0038] S12, start the profile measuring instrument and temperature sensor, and use the profile measuring instrument to register the measurement coordinate system with the machine tool coordinate system to obtain the spatial transformation parameters of the measurement system.

[0039] Start the profile measuring instrument and temperature sensor, and complete the registration of the measurement coordinate system and the machine tool working coordinate system according to the predetermined calibration procedure. The registration process includes measuring several known points using calibration components (such as a standard sphere, collimator, or known geometric blocks) to determine the spatial transformation relationship, and fitting the spatial transformation parameters (such as displacement and rotation components and scale factor) used for coordinate mapping. At the same time, confirm the installation position and recording channel of the temperature sensor, and correct the sensor offset.

[0040] S13 controls the hydraulic cylinder to perform a low-speed uniform test stroke, collects pressure data through its built-in pressure sensor, fits the hysteresis characteristic curve of the hydraulic cylinder, and calculates the hydraulic cylinder characteristic parameters with respect to nonlinear stiffness from the hysteresis characteristic curve.

[0041] A specified low-speed, uniform test stroke is performed on the hydraulic cylinder, while pressure-displacement data and pressure-time series are collected via a built-in pressure sensor and position feedback device. The collected data is filtered and fitted to identify the hysteresis characteristic curve of the hydraulic cylinder, from which the nonlinear stiffness, dead zone, and typical hysteresis behavior parameters (collectively referred to as hydraulic cylinder characteristic parameters) are extracted. This characteristic identification can employ fitting or model identification methods (e.g., least squares or recursive identification). The obtained characteristic parameters are used to establish an inverse model or feedforward compensator for the hydraulic cylinder, thereby mapping a control quantity closer to the actual executable quantity when generating the compensation trajectory, reducing tracking errors during the execution phase.

[0042] S14, based on spatial transformation parameters and hydraulic cylinder characteristic parameters, drives the contour measuring instrument to perform a zero-contact scan on the workpiece surface to obtain the registered initial surface contour data and reference temperature value.

[0043] Based on the established spatial transformation parameters and hydraulic cylinder characteristic parameters, the drive contour measuring instrument performs a zero-contact (or low-contact) scan on the clamped workpiece surface to acquire initial surface contour data registered to the working coordinate system in a non-destructive manner, while simultaneously recording the reference temperature values ​​of the workpiece surface and the environment. The obtained initial surface contour data, after denoising and registration, serves as the input for subsequent deviation calculations, while the reference temperature values ​​are used to consider thermal expansion or temperature-related corrections when generating compensation trajectories.

[0044] In this embodiment, step S3 specifically includes the following steps: S31 loads the first round of compensation trajectory file into the CNC system, performs a safety check on the hydraulic cylinder's motion range, and generates a verified grinding program.

[0045] It should be noted that the safety verification includes, but is not limited to: detecting displacement exceeding the hydraulic cylinder stroke in the trajectory, detecting feed speed or acceleration exceeding the machine tool / hydraulic system's capacity, and checking for tool and fixture interference that the trajectory may cause. If the verification passes, the CNC system generates an executable grinding program and records the verification results and program version in the execution log; if the verification fails, the trajectory is automatically or manually corrected and re-verified.

[0046] S32, start the grinding program and control the hydraulic cylinder to move along the compensation trajectory; at the same time, enable the execution log recording function to collect the workpiece temperature data in real time and compare it with the actual displacement data of the hydraulic cylinder.

[0047] S33, After the grinding process is completed, the contour measuring instrument is controlled to perform an initial rapid scan of the workpiece surface to obtain preliminary data of the post-grind contour. After grinding is completed, the contour measuring instrument is started to perform an initial rapid scan of the workpiece surface to obtain preliminary data of the post-grind contour; this rapid scan covers the entire target machining area with a relatively coarse sampling step, aiming to promptly detect macroscopic deviations or large-scale anomalies, while significantly shortening the measurement time to improve production cycle time.

[0048] S34: Based on the preliminary data, identify abnormal contour areas, adjust the sampling density of the measuring instrument to perform fine scanning measurement, and obtain complete post-grinding surface contour data; perform local analysis on the preliminary data to identify abnormal contour areas (such as out-of-tolerance sections, abrupt change points, or sections with large fluctuations), and adaptively adjust the sampling density of the contour measuring instrument accordingly. Perform fine scanning measurement with a finer step distance in the identified abnormal sections and their surroundings to obtain high-resolution complete post-grinding surface contour data; at the same time, record the measurement parameters of fine scanning and merge them with the preliminary scanning results to form a continuous high-precision point cloud.

[0049] S35 compares the post-grind surface profile data with the target morphology curve, and uses the temperature data in the execution log to compensate and correct the measurement results, and calculates the residual curve.

[0050] It should be noted that the obtained complete post-grinding surface contour data is compared point by point with the preset target morphology curve to calculate the initial residual distribution. Simultaneously, temperature-related geometric corrections are performed on the measurement results by combining the temperature sensor data from the execution log and the reference temperature recorded during clamping (e.g., backtracking compensation of coordinates based on linear or established thermal expansion models) to reduce measurement offsets caused by thermal deformation. During this process, obvious abnormal measurement points should be eliminated, and preliminary statistical analysis of the residuals (maximum residual, local trends, etc.) should be performed.

[0051] S36 performs smoothing filtering on the residual curve, generates secondary compensation amount based on preset compensation rules, and maps it to hydraulic cylinder displacement command to form secondary compensation trajectory file.

[0052] It should be noted that smoothing filtering is used to remove measurement noise and sharp local fluctuations, resulting in a continuous and executable compensation shape. Based on preset compensation rules (such as avoiding overcompensation, limiting the single compensation amplitude, and maintaining trajectory smoothness), the smoothed compensation amount is subject to scale or boundary constraints. The geometric compensation amount is then mapped to the corresponding hydraulic cylinder displacement command through the hydraulic cylinder inverse model, generating a secondary compensation trajectory file that conforms to dynamic and safety constraints.

[0053] In this embodiment, the iterative process of the secondary compensation trajectory file is specifically described as follows: S41, perform iterative grinding based on the secondary compensation trajectory file, and reacquire the contour data of the workpiece surface after each iteration; The secondary compensation trajectory file generated in the previous stage is sent to the CNC system and the iterative grinding cycle is executed. After each iteration of grinding is completed, the contour measuring instrument is used to re-acquire the complete contour data of the workpiece surface according to the predetermined measurement program, and the execution log of this iteration is recorded at the same time (including hydraulic cylinder target / actual displacement, pressure, grinding wheel status and temperature sequence, etc.).

[0054] This step requires that each measurement use the same or comparable registration procedure as the initial measurement to ensure data consistency. The remeasured data serves as the direct basis for residual calculation and compensation effect evaluation in the current iteration, while also providing the latest geometric error input and machine tool response information for subsequent iterations. By obtaining updated contour data after each iteration, the compensation strategy can be progressively verified and corrected, driving the residuals to converge towards the target shape.

[0055] S42 compares the contour data obtained after each iteration with the target shape curve, calculates the residual curve for that iteration, and determines whether it meets the final inspection criteria.

[0056] The contour data after each iteration is compared point by point with the pre-defined target topography curve to calculate and generate the residual curve for that iteration. Statistical and trend analysis is performed on the residual curve (e.g., local distribution of residuals, overall fluctuation trend and rate of change), and the source of error is identified by combining the temperature and displacement tracking information in the execution log. Based on predefined final inspection criteria (e.g., the residual has reached an acceptable range, the residual change tends to converge, or the number of iterations / process resources have reached the upper limit), it is determined whether the current iteration meets the processing termination conditions. If the conditions are not met, the next round of compensation is generated based on the residual characteristics and the compensation trajectory is updated (see S36 process), and the next round of iteration continues.

[0057] S43. When the final inspection criteria are met, the iteration is automatically terminated and the compensation trajectory sequence and corresponding residual curve of the entire processing of this workpiece are archived to the digital twin process library to generate initial compensation prediction parameters for similar workpieces.

[0058] When the final inspection criteria are met, the system automatically terminates the iteration process and integrates and archives the data of the entire workpiece processing process into the digital twin process library. The archived content includes the compensation trajectory sequence of each iteration, the corresponding residual curve, the complete execution log (displacement / pressure / temperature / timestamp), measurement data and calibration parameters, etc.

[0059] In this embodiment, the condition for generating the secondary compensation trajectory file is that the final inspection criterion is met as the termination condition; the final inspection criterion is that the maximum residual of the surface contour data after grinding is less than 0.01 mm or the root mean square value of the contour deviation is less than 0.005 mm.

[0060] It should be noted that the final inspection criterion is used to quantify the convergence state, which facilitates a consistent stopping decision in the closed-loop iteration. At the same time, the results should be reasonably corrected in conjunction with the temperature and displacement tracking information in the execution log during the judgment process to avoid misjudgment caused by instantaneous temperature fluctuations or measurement noise.

[0061] In this embodiment, the archived machining data includes the initial contour, the compensation trajectory for each round, the residual curve, and the temperature data of the workpiece during the compensation grinding process.

[0062] The key data generated during this processing will be systematically archived in a digital twin / process library. The archived content includes initial contour data, compensation trajectory files generated and executed in each round, corresponding residual curves, and workpiece temperature time series collected during the compensation grinding process (and may include displacement and pressure records from the execution log).

[0063] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A surface processing method for a guideway grinding machine, characterized in that, Includes the following steps: S1, by clamping the workpiece and initializing the measurement system and hydraulic cylinder of the calibrated grinding machine, the initial surface contour data and reference temperature value of the workpiece are obtained; S2, based on the initial surface contour data and the preset target concave / convex topography curve, calculate the initial deviation and generate the first round of compensation trajectory file by fitting; S3. Based on the first round of compensation trajectory file, control the hydraulic cylinder of the grinding machine to perform the compensation grinding process. After the grinding is completed, perform offline contour measurement, obtain the surface contour data after grinding, calculate the residual curve, and generate a secondary compensation trajectory file.

2. The surface processing method for a guideway grinding machine according to claim 1, characterized in that, The process of generating the first round of compensation trajectory file specifically includes: smoothing and fitting the initial deviation to generate the compensation amount, and then mapping the compensation amount to the target displacement sequence of the hydraulic cylinder through the inverse kinematics model of the hydraulic cylinder that includes hysteresis and nonlinearity, and generating a trajectory file in the form of a CNC program.

3. The surface processing method for a guideway grinding machine according to claim 1, characterized in that, During the compensation grinding process, the temperature data of the workpiece is collected in real time and recorded together with the actual displacement data of the hydraulic cylinder in the execution log; if the tracking deviation between the actual displacement of the hydraulic cylinder and the target displacement exceeds the preset threshold, real-time adjustment or pause is triggered.

4. The surface processing method for a guideway grinding machine according to claim 1, characterized in that, Step S1 specifically includes the following steps: S11, clamp the workpiece on the worktable, and use standard gauge blocks and torque wrench to ensure the uniformity of the clamping plane reference and the uniform distribution of clamping force; S12, start the contour measuring instrument and temperature sensor, and use the contour measuring instrument to register the measurement coordinate system with the machine tool coordinate system to obtain the spatial transformation parameters of the measurement system; S13 controls the hydraulic cylinder to perform a low-speed uniform test stroke, collects pressure data through its built-in pressure sensor, fits the hysteresis characteristic curve of the hydraulic cylinder, and calculates the hydraulic cylinder characteristic parameters with respect to nonlinear stiffness from the hysteresis characteristic curve. S14, based on the spatial transformation parameters and hydraulic cylinder characteristic parameters, drive the contour measuring instrument to perform a zero-contact scan on the workpiece surface to obtain the registered initial surface contour data and reference temperature value.

5. The surface processing method for a guideway grinding machine according to claim 1, characterized in that, Step S3 specifically includes the following steps: S31, load the first round compensation trajectory file into the CNC system, perform a safety check on the hydraulic cylinder's motion range, and generate a verified grinding program; S32, start the grinding program and control the hydraulic cylinder to move along the compensation trajectory; S33, after the grinding process is completed, the control contour measuring instrument performs the first rapid scan on the workpiece surface to obtain preliminary data of the post-grind contour.

6. The surface processing method for a guideway grinding machine according to claim 5, characterized in that, The step S33 is followed by: S34. Based on the preliminary data, identify abnormal contour areas, adjust the sampling density of the measuring instrument to perform fine scanning and obtain complete post-grind surface contour data. S35, compare the post-grinding surface contour data with the target morphology curve, and compensate and correct the measurement results by combining the temperature data in the execution log, and calculate the residual curve; S36, the residual curve is smoothed and filtered, a secondary compensation amount is generated based on the preset compensation rules, and mapped to the hydraulic cylinder displacement command to form a secondary compensation trajectory file.

7. The surface processing method for a guideway grinding machine according to claim 1, characterized in that, The step S3 is followed by: S4. Based on the secondary compensation trajectory file, perform iterative correction grinding until the final inspection criteria are met, and archive the processing data during the grinding process to the process library for optimizing the processing of similar workpieces.

8. The surface processing method for a guideway grinding machine according to claim 7, characterized in that, The iterative process of the secondary compensation trajectory file is as follows: S41, perform iterative grinding based on the secondary compensation trajectory file, and reacquire the contour data of the workpiece surface after each iteration; S42, compare the contour data obtained after each iteration with the target topography curve, calculate the residual curve for that iteration and determine whether it meets the final inspection criteria; S43. When the final inspection criteria are met, the iteration is automatically terminated and the compensation trajectory sequence and corresponding residual curve of the entire processing of this workpiece are archived to the digital twin process library to generate initial compensation prediction parameters for similar workpieces.

9. The surface processing method for a guideway grinding machine according to claim 8, characterized in that, The condition for generating the secondary compensation trajectory file is that the final inspection criterion is met as the termination condition. The final inspection criterion is that the maximum residual of the surface contour data after grinding is less than 0.01 mm or the root mean square value of the contour deviation is less than 0.005 mm.

10. The surface processing method for a guideway grinding machine according to claim 8, characterized in that, The archived machining data includes the initial profile, compensation trajectory for each round, residual curve, and workpiece temperature data during the compensation grinding process.

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