Method, system, terminal and medium for correcting reference points in machining of numerically controlled machine tools

Abstract

The present invention belongs to the field of CNC machine tool processing technology and specifically discloses a CNC machine tool reference point correction method, system, terminal, and medium. The method comprises: obtaining three-dimensional coordinate information of the machine tool working area; extracting the actual position of a preset reference point on the machine tool based on the three-dimensional coordinate information, comparing it with a preset theoretical reference point, and calculating a deviation value; performing coordinate deviation aggregation analysis based on the deviation value to determine coordinate system correction parameters including a translation vector and a rotation matrix; sending the correction parameters to the CNC machine tool control system to update the current workpiece coordinate system; after the coordinate system is updated, continuing the processing task and monitoring the processing status in real time. If a deviation exceeding a threshold is detected, the measurement and correction process is automatically re-triggered. The method can realize automatic correction of reference points and real-time compensation of the workpiece coordinate system, improving processing accuracy and reducing manual intervention, and is suitable for high-precision CNC processing scenarios.

Description

Technical Field

[0001] The present invention belongs to the technical field of numerical control machine tool processing, and in particular relates to a method, system, terminal and medium for correcting a reference point in numerical control machine tool processing. Background Art

[0002] As the manufacturing industry continues to become more intelligent, CNC machine tools are increasingly used in high-precision, high-efficiency machining. During CNC machining, machine tool reference points (such as the workpiece coordinate system origin and datum planes) serve as the basis for machining path generation and position control. Their accuracy directly impacts the product's geometric accuracy and assembly quality.

[0003] However, in actual production environments, machine tool reference points can be affected by a variety of factors, such as thermal expansion, long-term mechanical wear, fixture repetitive installation errors, and vibration shock, causing the reference point to gradually shift during the machining process. If this shift is not detected and corrected in a timely manner, it will directly cause workpiece machining errors and even product scrapping, seriously affecting manufacturing stability and yield.

[0004] Traditional reference point correction methods rely heavily on manual intervention, requiring position calibration using a micrometer, tool setter, or manual alignment with a known reference surface. This is not only time-consuming and inefficient, but the calibration process is also susceptible to human interference and cannot meet the automated production line's requirements for "high precision, low downtime, and closed-loop control." Summary of the Invention

[0005] In response to the problems in the prior art, the present invention provides a method, system, terminal and medium for correcting reference points in CNC machine tool processing, which solves the problem that traditional reference point correction methods in the prior art rely heavily on manual intervention and require position calibration through micrometers, tool setting gauges or manual alignment with known reference surfaces. This is not only time-consuming and inefficient, but the calibration process is also easily interfered with by human factors.

[0006] The technical solution adopted in the present invention is as follows:

[0007] In a first aspect, the present application provides a method for correcting a reference point in machining a CNC machine tool, the method comprising the following steps:

[0008] Step S1, obtaining the three-dimensional coordinate information of the machine tool working area;

[0009] Step S2: Based on the acquired three-dimensional coordinate information, extract the actual coordinates of the preset reference points on the machine tool, and compare them with the reference coordinates of the preset reference points to obtain the deviation values ​​from each reference point;

[0010] Step S3: performing coordinate deviation aggregation analysis on the deviation values ​​of each reference point to determine a set of correction parameters for coordinate system correction, the correction parameters including a translation vector and a rotation matrix;

[0011] Step S4: Send the correction parameters to the CNC machine tool control system to update the workpiece coordinate system used in the current machine tool processing;

[0012] Step S5: After the coordinate system is updated, the CNC machining task is continued according to the machining program.

[0013] Furthermore, in step S1, three-dimensional coordinate information of the machine tool working area is obtained by three-dimensional scanning, specifically including:

[0014] Use laser scanning, structured light or optical measurement technology to collect 3D data from multiple angles of the machine tool processing area and generate a point cloud data set;

[0015] The point cloud data is pre-processed to form the three-dimensional coordinate information of the machine tool working area;

[0016] Preprocessing includes filtering and denoising, coordinate transformation and registration.

[0017] Furthermore, in step S2, the scanned point cloud in the obtained 3D coordinate information is registered with the preset CAD model, and the corresponding reference point positions are determined by minimizing the following error function through the iterative closest point algorithm, and the point pair weight factor is added in each iteration. , the error function is:

[0018]

[0019] in, is the objective function value of the error function, R is the rotation matrix, T is the translation vector, is the ith actual point, is the i-th reference point, N is the weight factor According to the local curvature of the point cloud Calculate to satisfy:

[0020]

[0021] in, is the adjustment coefficient preset by experience, Estimated by the ratio of the principal curvatures of the neighborhood.

[0022] Furthermore, in step S3, the coordinate deviation aggregation analysis includes: based on the constructed actual point coordinate set and the reference point coordinate set, using a rigid body posture fitting method, estimating the global coordinate system correction parameters R and T by minimizing the following unweighted Euclidean error function:

[0023] .

[0024] Furthermore, in step S4, the updating process includes:

[0025] Perform format conversion on the received correction parameters based on the internal coordinate system of the CNC system;

[0026] Adjust the origin position and rotation angle of the workpiece coordinate system in the CNC system.

[0027] Furthermore, in step S5, after the coordinate system is updated, the CNC machine tool control system continues to execute the CNC machining task according to the updated workpiece coordinate system and the pre-set machining program parameters, and monitors the machining status in real time;

[0028] If a processing deviation or anomaly is detected, the process automatically triggers re-measurement and correction by jumping to step S1.

[0029] Furthermore, the process of detecting processing deviations or anomalies includes:

[0030] During the machining process, the actual motion trajectory data from the machine tool is continuously collected and compared with the target trajectory set in the machining program;

[0031] When the deviation between the actual trajectory and the target trajectory exceeds the preset error threshold, the system determines that there is a processing deviation or abnormality;

[0032] After detecting an abnormality, the control system automatically pauses the current processing task.

[0033] And restart the whole process from reference point measurement, deviation analysis to coordinate system update,

[0034] To correct the machining error caused by reference point drift, and then continue to execute the machining task.

[0035] In a second aspect, the present application provides a CNC machine tool reference point correction system, the system comprising:

[0036] The 3D data acquisition module is used to obtain the 3D coordinate information of the machine tool working area. The 3D coordinate information is obtained through laser scanning, structured light or optical measurement, and is pre-processed to form high-precision point cloud data;

[0037] The reference point extraction and registration module is used to extract the actual position of the preset reference point on the machine tool from the three-dimensional coordinate information and compare it with the preset reference point model to determine the spatial deviation between the reference points;

[0038] Deviation calculation and aggregation module, used to perform coordinate deviation aggregation analysis based on the spatial deviation between point pairs and determine the coordinate system correction parameters including translation vector and rotation matrix;

[0039] The control instruction generation module is used to convert the correction parameters into workpiece coordinate system update instructions compatible with the CNC system and send them to the CNC machine tool in real time;

[0040] The machining control module is used to continue the machining task according to the updated workpiece coordinate system and monitor the actual machining status during the machining process;

[0041] The self-feedback trigger module is used to automatically start the reference point re-measurement and correction process when it detects that the processing deviation exceeds the threshold, thereby realizing real-time closed-loop correction of the processing coordinate system.

[0042] In a third aspect, the present application provides a terminal, including:

[0043] A memory for storing a reference point correction program for CNC machine tool processing;

[0044] A processor is used to implement the steps of the CNC machine tool processing reference point correction method as described in the first aspect when executing the CNC machine tool processing reference point correction system.

[0045] In a fourth aspect, the present application provides a computer-readable storage medium, which stores computer instructions. When a computer reads the computer instructions in the storage medium, the computer executes the CNC machine tool processing reference point correction method as described in the first aspect.

[0046] It can be seen from the above technical solutions that the advantages of the present invention are:

[0047] (1) The present invention obtains the three-dimensional coordinate information of the machine tool processing area, extracts the actual reference point position, compares it with the theoretical reference point, calculates the coordinate deviation, and corrects the processing coordinate system accordingly. This method can effectively solve the problem of reference point position drift caused by thermal deformation, clamping errors, equipment wear, etc. The method constructs a closed-loop process from deviation detection to parameter calculation to coordinate update, significantly improving the spatial positioning accuracy of machine tool processing, reducing the need for manual intervention, and meeting the high-precision and automation requirements of intelligent manufacturing.

[0048] (2) By adopting various 3D acquisition methods such as laser scanning, structured light or optical measurement, and filtering, denoising, coordinate transformation and registration processing of the generated point cloud data, the accuracy and robustness of the 3D modeling of the machine tool working area are improved. This provides a high-quality data foundation for subsequent reference point identification and deviation analysis, and reduces extraction errors caused by noise or environmental interference.

[0049] (3) Align the 3D scan point cloud with the preset CAD model, and achieve more accurate point correspondence recognition by introducing a weighted iterative closest point algorithm. The weight factor is automatically calculated based on the local curvature characteristics of the point cloud, which can effectively suppress the registration error in high curvature areas, thereby enhancing the registration accuracy and robustness, and ensuring the stability and reliability of the reference point extraction results;

[0050] By adopting the rigid body posture fitting method, the global coordinate correction parameters (rotation matrix and translation vector) are further extracted based on the determined point correspondence. By minimizing the unweighted Euclidean distance between point pairs, the overall error of the coordinate system is uniformly corrected, avoiding the local error accumulation problem caused by local point compensation and improving the coordinate consistency of the entire machining system. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the technical solution of the present invention, the following is a brief introduction to the drawings required for the description. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0052] Figure 1 The figure is a flow chart of the reference point correction method for CNC machine tools. DETAILED DESCRIPTION

[0053] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0054] See also Figure 1 As shown, the present invention provides a method for correcting a reference point in a CNC machine tool, comprising the following steps:

[0055] Step S1, obtaining the three-dimensional coordinate information of the machine tool working area;

[0056] Step S2: Based on the acquired three-dimensional coordinate information, extract the actual coordinates of the preset reference points on the machine tool, and compare them with the reference coordinates of the preset reference points to obtain the deviation values ​​from each reference point;

[0057] Step S3: performing coordinate deviation aggregation analysis on the deviation values ​​of each reference point to determine a set of correction parameters for coordinate system correction, the correction parameters including a translation vector and a rotation matrix;

[0058] Step S4: Send the correction parameters to the CNC machine tool control system to update the workpiece coordinate system used in the current machine tool processing;

[0059] Step S5: After the coordinate system is updated, the CNC machining task is continued according to the machining program.

[0060] In some embodiments, in step S1, obtaining three-dimensional coordinate information of the machine tool working area through three-dimensional scanning specifically includes:

[0061] In a preferred embodiment of the present invention, the process for obtaining three-dimensional coordinate information of the working area of ​​a machine tool is carried out based on high-precision three-dimensional scanning technology. The scanning technology may include laser scanning, structured light measurement, or industrial optical imaging. The specific selection can be configured according to the type of machine tool, the processing environment, and the measurement accuracy requirements.

[0062] During the actual operation of the system, the three-dimensional scanning equipment is arranged at an appropriate position in the machine tool processing space. For example, it can be installed on the machine tool spindle, near the workpiece, or inside the processing cabin. Multi-angle scanning is achieved through the movement of the equipment or the installation of multiple sensors. During the scanning process, the system synchronously controls the image acquisition from each perspective so that the acquired data can fully cover the entire working area, especially the location of the reference point and its neighborhood. After the acquisition process is completed, the system automatically integrates the scanning results from each perspective to generate a point cloud data set containing a large number of discrete spatial sampling points. As the geometric basis for subsequent reference point identification and coordinate comparison, this point cloud data must have sufficient density and spatial consistency.

[0063] To ensure that the point cloud data has high precision and low redundancy in subsequent analysis, the system performs a series of preprocessing operations on the original point cloud data. First, the noise points in the scan data are identified and eliminated through a spatial filtering algorithm. Noise points usually come from factors such as scanning shadows, surface reflections, or environmental interference. Typical filtering methods may include filtering mechanisms based on statistical outlier judgment or neighborhood density analysis. Secondly, the point cloud data is converted from the device's own coordinate system to a coordinate system consistent with the CNC machine tool. This process can perform coordinate mapping based on the coordinate transformation relationship pre-calibrated by the machine tool to ensure that all spatial information is uniformly represented in the machine tool processing reference system.

[0064] Furthermore, to enhance the geometric continuity between multi-view point clouds, the system also performs point cloud registration on multiple scans. This registration process can be performed using reference blocks, calibration spheres, or natural feature surfaces to ensure spatial alignment between each segment of the point cloud. Ultimately, the filtered, transformed, and registered point cloud data is structured and stored and submitted to the reference point extraction module for further extraction of target geometric features and accurate identification of the machining reference point locations.

[0065] In some embodiments, in step S2, the scanned point cloud in the acquired three-dimensional coordinate information is aligned with the preset CAD model, and the corresponding reference point positions are determined by minimizing the following error function through an iterative closest point algorithm, and a point pair weight factor is added in each iteration. , the error function is:

[0066]

[0067] in, is the objective function value of the error function, R is the rotation matrix, T is the translation vector, is the ith actual point, is the i-th reference point, N is the weight factor According to the local curvature of the point cloud Calculate to satisfy:

[0068]

[0069] in, is the adjustment coefficient preset by experience, Estimated by the ratio of the principal curvatures of the neighborhood.

[0070] In some embodiments, in step S3, the coordinate deviation aggregation analysis includes: estimating the global coordinate system correction parameters R and T by minimizing the following unweighted Euclidean error function based on the constructed actual point coordinate set and the reference point coordinate set using a rigid body pose fitting method:

[0071] .

[0072] In some embodiments, in a preferred embodiment of the present invention, for the correction parameter issuance and coordinate system update process described in step S4, after the system completes the reference point deviation analysis and outputs correction parameters such as translation vector and rotation matrix, it needs to transmit this set of parameters to the CNC machine tool control system for actual coordinate correction.

[0073] Specifically, the system first formats and converts the calculated correction parameters to ensure they conform to the coordinate representation specifications currently used by the CNC system. Different CNC systems may use different coordinate system definitions, data structure formats, or instruction languages. For example, some systems use a right-handed Cartesian coordinate system combined with Euler angles to describe rotation relationships, while others may use homogeneous transformation matrices or quaternions for coordinate transformation representation. Therefore, before the parameters are issued, the coordinate system projection, data reorganization, and unit conversion of the correction parameters must be completed according to the interface protocol and data requirements of the target CNC system so that they can be accurately recognized and accepted by the control system.

[0074] After format conversion, the system transmits the processed coordinate system correction instructions to the CNC system kernel via a standard communication interface (such as Ethernet, RS-232, or fieldbus). Upon receiving this instruction, the control system shifts the origin position set in the original workpiece coordinate system according to the new translation parameters and corrects the orientation of the coordinate axes based on the rotation parameters. This means adjusting the angles between the axes in the workpiece coordinate system and the machine tool coordinate system, thereby realigning the machining path in space with the corrected reference point set.

[0075] The coordinate system update is processed as a change to the basic spatial configuration in the CNC system. The new workpiece coordinate system takes effect immediately and serves as the basic coordinate framework for subsequent machining program execution. This step enables global coordinate reconstruction based on reference point offsets, avoiding the inefficient practice of point-by-point interpolation path adjustment within the program and significantly improving the automation and system integration of reference point error correction.

[0076] In some embodiments, in preferred embodiments of the present invention, with respect to step S5, after the coordinate system update is complete, the CNC machine tool control system will immediately resume machining using the new workpiece coordinate system as the reference. "Continue" here does not mean reloading the entire program. Rather, it means dynamically switching to the revised spatial reference without interrupting the current production plan, thereby maintaining a high degree of consistency between the machining path and the actual workpiece position, and avoiding dimensional deviations or geometric errors caused by reference point drift.

[0077] Path planning, feed rates, tool compensation parameters, and other parameters defined in the machining program can all be seamlessly applied while maintaining a consistent coordinate system, eliminating the need to modify the original program logic. Updating the coordinate system essentially only affects the spatial resolution method in the CNC system and does not affect the structure of the machining instructions. This approach ensures real-time and minimally invasive corrections, making it suitable for high-precision continuous machining scenarios.

[0078] While executing machining tasks, the CNC system continuously monitors the machining status in real time. This includes position feedback from the machine's moving parts, spindle speed and load, tool path execution, and workpiece surface profile data (if an online measurement device is available). The system continuously samples and compares these operating parameters to determine if any machining anomalies exist. For example, if the actual trajectory deviates from the planned path by more than a set threshold, or if there is a significant discrepancy between the measured result and the theoretical dimension, this is considered a machining deviation exceeding the specified limit.

[0079] If a machining anomaly is detected, the control system immediately terminates the current machining task and triggers the system to jump back to the initial step S1, restarting the 3D scanning, reference point extraction, and coordinate system correction process. This process implements a fully automatic, closed-loop reference point correction strategy, enabling the system to quickly respond and dynamically correct errors in the face of external disturbances, clamping errors, or thermal deformation. After re-correction, the system will continue machining in the new coordinate system, ensuring that the entire process remains under high-precision control, avoiding error accumulation and manual intervention, and significantly improving machining quality and automation.

[0080] In some embodiments, the process of detecting processing deviations or anomalies includes:

[0081] In a preferred embodiment of the present invention, in order to ensure that the processing accuracy is continuously guaranteed during the actual operation process after the reference point is corrected, the system introduces an automatic deviation monitoring and feedback correction mechanism to achieve real-time monitoring and closed-loop response of the processing status.

[0082] Specifically, throughout the CNC machine tool's machining process, the control system continuously collects real-time trajectory information from each axis. This trajectory information can include encoder feedback values ​​for each axis, actual position information from interpolated paths, and position measurement data from built-in or external sensors (such as laser interferometers and grating rulers).

[0083] The system compares and analyzes this collected data with the target trajectory preset in the machining program. The target trajectory, which can be extracted from machining instructions (G-code) or toolpath planning files, represents the ideal spatial path the tool should take. During this comparison, the control system calculates the deviation between the target position and the actual position, using a set error threshold as the basis for judgment.

[0084] When the comparison results show that the trajectory deviation at any sampling point or within a continuous segment exceeds the preset limit, for example, the deviation value is greater than the part size tolerance, the tool trajectory smoothness is abnormal, or the machining surface quality monitoring data is abnormal, the system determines that the current machining has deviated or there is a potential failure risk.

[0085] Upon confirming an anomaly, the control system immediately interrupts the current machining task to prevent further errors and the creation of scrap. Simultaneously, the system automatically transitions to the reference point correction process, restarting the 3D data acquisition, reference point extraction, deviation analysis, coordinate system correction, and updating the workpiece coordinate system used by the CNC system. Once the correction is complete, the machining program resumes execution in the new coordinate system, smoothly resuming the task from the point of interruption, ensuring overall machining quality and precision control.

[0086] In some embodiments, the present application provides a CNC machine tool reference point correction system, the system comprising:

[0087] The 3D data acquisition module is used to obtain the 3D coordinate information of the machine tool working area, providing the geometric data foundation for subsequent reference point identification and coordinate correction. The 3D coordinate information can be acquired using measurement equipment such as laser scanners, structured light sensors, or industrial-grade optical probes.

[0088] In practice, the measurement device can be deployed around the machine tool's machining space or mounted on the machine tool's spindle, enabling multi-angle spatial scanning. The collected raw point cloud data undergoes data preprocessing, including filtering, noise reduction, coordinate system conversion, and registration, generating high-quality 3D coordinate information that meets the accuracy requirements for reference point extraction.

[0089] The point cloud preprocessing process includes but is not limited to the following operations:

[0090] Noise suppression is achieved using algorithms such as bilateral filtering and statistical outlier removal;

[0091] Perform spatial registration on multi-viewpoint collected point cloud data and unify them to the machine tool coordinate system;

[0092] Interpolate and complete the scan boundary area or occluded area to improve the completeness of the point cloud.

[0093] The reference point extraction and registration module is used to identify the locations of reference points preset on the machine tool from the processed 3D coordinate information and spatially match them with the reference points marked in the theoretical CAD model. To improve matching accuracy, this embodiment uses a weighted iterative closest point (ICP) algorithm based on local feature curvature.

[0094] In the specific process, the system uses the scanned point cloud and the preset reference point model as two sets of input data. It uses the ratio of the principal curvatures within the spatial neighborhood to estimate the matching weights between point pairs, dynamically adjusting the weight factors during the registration iteration process to improve the final matching alignment. The reference point spatial deviation data output by this module is used for subsequent coordinate correction parameter calculations.

[0095] Deviation calculation and aggregation module, which is used to summarize and analyze the deviation values ​​between the extracted actual reference point positions and the theoretical reference point positions, and then calculate a set of correction parameters that describe the transformation relationship of the spatial coordinate system, including the rotation matrix and translation vector.

[0096] This embodiment uses a rigid body posture transformation fitting method to perform an overall fitting of all reference point offsets based on the Euclidean least squares criterion to ensure that the resulting coordinate correction parameters are globally consistent. These parameters are then passed as input to the control instruction generation module.

[0097] The control instruction generation module is used to convert the rotation matrix and translation vector calculated in the previous step into the workpiece coordinate system update instruction that can be recognized and executed by the CNC system.

[0098] During the specific implementation process, the system adapts the coordinate format of the correction parameters, generates update instructions based on the G code used by the CNC system or the internal coordinate variable structure of the system, and sends them to the machine tool control unit through the industrial bus (such as EtherCAT, PROFINET, etc.) to complete the real-time correction of the workpiece coordinate system.

[0099] The processing control module is used to continue executing the original processing program after the workpiece coordinate system is updated, and dynamically monitor the status data during the processing.

[0100] The system controls the machine tool to execute machining tasks according to the updated coordinate system by invoking the feed parameters, tool paths, and other instructions set in the machining program. During machining, the module continuously collects information including spindle load, displacement feedback, machining path, and tool vibration for subsequent abnormality detection.

[0101] The self-feedback trigger module is used to establish the closed-loop control capability of the system. When the machine tool processing trajectory is detected to be offset from the target trajectory beyond the set tolerance, or when other key parameters are abnormal, the reference point re-measurement and coordinate update process are automatically triggered.

[0102] This module integrates processing error judgment logic, determining whether reference point scanning and coordinate updates are necessary based on processing error thresholds, trend analysis, or feedback from multiple processing cycles. If the trigger conditions are met, the system automatically jumps to the 3D data acquisition module to perform a new round of reference point extraction, registration, calculation, and compensation, achieving real-time closed-loop correction without manual intervention.

[0103] In some embodiments, the present application provides a terminal, including:

[0104] A memory for storing a reference point correction program for CNC machine tool processing;

[0105] A processor is used to implement the steps of the CNC machine tool processing reference point correction method when executing the CNC machine tool processing reference point correction system.

[0106] In some embodiments, the present application provides a computer-readable storage medium, which stores computer instructions. When a computer reads the computer instructions in the storage medium, the computer executes the CNC machine tool processing reference point correction method.

[0107] It is understood that the systems, devices, modules, or units described in the above embodiments may be implemented by computer chips or physical devices, or by products having certain functions. A typical implementation device is a computer, which may be a personal computer, a laptop computer, a personal digital assistant, a tablet computer, a wearable device, or a combination of any of these devices.

[0108] In a typical configuration, a computer includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0109] Memory may include non-permanent storage in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. Memory is an example of a computer-readable medium.

[0110] Computer-readable media include permanent and non-permanent, removable and non-removable media that can be used to store information using any method or technology. Information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, disk storage, quantum memory, graphene-based storage media or other magnetic storage devices, or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory media such as modulated data signals and carrier waves.

[0111] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with the relevant laws, regulations and standards of relevant countries and regions, and provide corresponding operation entrances for users to choose to authorize or refuse.

[0112] It should also be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, commodity, or apparatus that includes a series of elements includes not only those elements but also other elements not explicitly listed, or includes elements inherent to such process, method, commodity, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, method, commodity, or apparatus that includes the element.

[0113] The foregoing description of this specification describes specific embodiments. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims can be performed in an order different from that described in the embodiments and still achieve the desired results. Furthermore, the processes depicted in the accompanying drawings do not necessarily require the specific order shown or the sequential order to achieve the desired results. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0114] The terms used in one or more embodiments of this specification are for the purpose of describing specific embodiments only and are not intended to limit one or more embodiments of this specification. The singular forms "a," "an," "the," and "the" used in one or more embodiments of this specification and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0115] It should be understood that although the terms first, second, third, etc. may be used to describe various information in one or more embodiments of this specification, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of one or more embodiments of this specification, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when..." or "when..." or "in response to determining."

[0116] The above description is merely a preferred embodiment of one or more embodiments of this specification and is not intended to limit one or more embodiments of this specification. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of one or more embodiments of this specification shall be included in the scope of protection of one or more embodiments of this specification.

Claims

1. A method for correcting a reference point in a CNC machine tool, characterized in that: The following steps are involved: Step S1, obtaining the three-dimensional coordinate information of the machine tool working area; Step S2: Based on the acquired three-dimensional coordinate information, extract the actual coordinates of the preset reference points on the machine tool, and compare them with the reference coordinates of the preset reference points to obtain the deviation values ​​from each reference point; Step S3: performing coordinate deviation aggregation analysis on the deviation values ​​of each reference point to determine a set of correction parameters for coordinate system correction, the correction parameters including a translation vector and a rotation matrix; The scanned point cloud in the acquired 3D coordinate information is registered with the preset CAD model, and the corresponding reference point position is determined by minimizing the following error function through the iterative closest point algorithm, and the point pair weight factor is added in each iteration , the error function is: in, is the objective function value of the error function, R is the rotation matrix, T is the translation vector, is the ith actual point, is the i-th reference point, N is the weight factor According to the local curvature of the point cloud Calculate to satisfy: in, is the adjustment coefficient preset by experience, Estimated by the ratio of the principal curvatures of the neighborhood; Coordinate deviation aggregation analysis includes: based on the constructed actual point coordinate set and reference point coordinate set, using the rigid body posture fitting method to estimate the global coordinate system correction parameters R and T by minimizing the following unweighted Euclidean error function: ； Step S4: Send the correction parameters to the CNC machine tool control system to update the workpiece coordinate system used in the current machine tool processing; Step S5: After the coordinate system is updated, the CNC machining task is continued according to the machining program.

2. The method for correcting a reference point in a CNC machine tool according to claim 1, wherein: In step S1, three-dimensional coordinate information of the machine tool working area is obtained through three-dimensional scanning, which specifically includes: Use laser scanning, structured light or optical measurement technology to collect 3D data from multiple angles of the machine tool processing area and generate a point cloud data set; The point cloud data is pre-processed to form the three-dimensional coordinate information of the machine tool working area; Preprocessing includes filtering and denoising, coordinate transformation and registration.

3. The method for correcting a reference point in a CNC machine tool according to claim 1, wherein: In step S4, the update process includes: Perform format conversion on the received correction parameters based on the internal coordinate system of the CNC system; Adjust the origin position and rotation angle of the workpiece coordinate system in the CNC system.

4. The method for correcting a reference point in a CNC machine tool according to claim 1, wherein: In step S5, after the coordinate system is updated, the CNC machine tool control system continues to execute the CNC machining task according to the updated workpiece coordinate system and the pre-set machining program parameters, and monitors the machining status in real time; If a processing deviation or anomaly is detected, the process automatically triggers re-measurement and correction by jumping to step S1.

5. The method for correcting a reference point in machining a CNC machine tool according to claim 4, wherein: The process of detecting machining deviations or anomalies includes: During the machining process, the actual motion trajectory data from the machine tool is continuously collected and compared with the target trajectory set in the machining program; When the deviation between the actual trajectory and the target trajectory exceeds the preset error threshold, the system determines that there is a processing deviation or abnormality; After detecting an abnormality, the control system automatically pauses the current processing task. And restart the whole process from reference point measurement, deviation analysis to coordinate system update, To correct the machining error caused by reference point drift, and then continue to execute the machining task.

6. A CNC machine tool reference point correction system, used to implement the CNC machine tool reference point correction method according to claim 1, characterized in that: The system includes: The 3D data acquisition module is used to obtain the 3D coordinate information of the machine tool working area. The 3D coordinate information is obtained through laser scanning, structured light or optical measurement, and is pre-processed to form high-precision point cloud data; The reference point extraction and registration module is used to extract the actual position of the preset reference point on the machine tool from the three-dimensional coordinate information and compare it with the preset reference point model to determine the spatial deviation between the reference points; Deviation calculation and aggregation module, used to perform coordinate deviation aggregation analysis based on the spatial deviation between point pairs and determine the coordinate system correction parameters including translation vector and rotation matrix; The control instruction generation module is used to convert the correction parameters into workpiece coordinate system update instructions compatible with the CNC system and send them to the CNC machine tool in real time; The machining control module is used to continue the machining task according to the updated workpiece coordinate system and monitor the actual machining status during the machining process; The self-feedback trigger module is used to automatically start the reference point re-measurement and correction process when it detects that the processing deviation exceeds the threshold, thereby realizing real-time closed-loop correction of the processing coordinate system.

7. A terminal, characterized in that: include: A memory for storing a reference point correction program for CNC machine tool processing; A processor is used to implement the steps of the CNC machine tool processing reference point correction method as claimed in claim 1 when executing the CNC machine tool processing reference point correction system.

8. A computer-readable storage medium, characterized in that The storage medium stores computer instructions. When the computer reads the computer instructions in the storage medium, the computer executes the CNC machine tool processing reference point correction method as claimed in claim 1.

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