Automatic compensation numerical control system and control method thereof

Abstract

The invention provides an automatic compensation numerical control system and a control method thereof, and the method comprises the steps: collecting displacement data of a drive unit in the movement process of a servo shaft, converting the displacement data into a displacement sequence of the drive unit, decomposing the displacement sequence of the drive unit into a plurality of vibration sequences, determining a transmission characteristic value and a vibration index of each vibration sequence, and carrying out the automatic compensation. Extracting a plurality of impact sequences from all the vibration sequences through all the transmission characteristic values and the vibration indexes, reconstructing all the impact sequences into abnormal vibration data, determining the oscillation degree of the servo shaft movement process according to the abnormal vibration data, and judging whether oscillation occurs in the servo shaft movement process according to the oscillation degree. The servo gain of the driving unit is adjusted according to the judgment result, the servo gain of the driving unit is adjusted according to the vibration condition of the driving unit, and stable movement of the servo shaft can be achieved under the condition that the disturbance degree of the driving unit is low.

Description

Technical Field

[0001] This application relates to the field of numerical control system technology, and more specifically, to an automatic compensation numerical control system and its control method. Background Technology

[0002] Numerical control (NC) systems are the core of modern precision manufacturing equipment. They control motors via servo drives, which in turn drive the worktable or spindle to perform precise movements through transmission mechanisms (such as ball screws). The dynamic performance of the servo axes directly determines machining accuracy, surface quality, and efficiency. To ensure smooth and precise movement, feedback on position and speed errors (such as PID control) is typically used to adjust the gain parameters of the servo loop in real time.

[0003] In actual machining, progressive tool wear, workpiece material inhomogeneity, instantaneous changes in cutting load, and minute clearances or lubrication changes in mechanical transmission components (such as lead screws and guide rails) all introduce complex, time-varying internal disturbances into the servo system. These disturbances are not tracking errors in the traditional sense, but often manifest as abnormal vibrations or torque impacts at specific frequencies. Existing technologies mainly rely on error amplitude for feedback correction, making it difficult to effectively identify and distinguish these abnormal dynamics with specific patterns caused by process or mechanical conditions from the system's normal motion response in the early stages. Therefore, when the disturbance level has not yet reached the point of causing significant deviations or alarms, fixed control parameters may not provide optimal damping, resulting in slight oscillations of the servo axis during start-up, reversal, or continuous motion. Such unsuppressed oscillations will be transmitted to the machining process, causing surface chatter marks on the workpiece, decreased dimensional accuracy, and, with long-term operation, may accelerate mechanical wear or even cause equipment failure. Therefore, how to proactively identify and adaptively compensate for these abnormal dynamics in the early stages when the disturbance level is low and has not yet significantly affected machining, in order to achieve continuous, stable, and high-precision motion of the servo axis, has become a pressing problem to be solved in the industry. Summary of the Invention

[0004] This application provides an automatically compensated CNC system and its control method, which can achieve smooth motion of the servo axis under conditions of low disturbance of the drive unit.

[0005] In a first aspect, this application provides a control method for an automatically compensated CNC system, specifically including the following steps: The displacement data of the drive unit during the servo axis motion is collected and converted into a displacement sequence of the drive unit; The displacement sequence of the drive unit is decomposed into multiple vibration sequences, and the transmission characteristic value and vibration index of each vibration sequence are determined. Multiple impact sequences are extracted from all vibration sequences using all transmission characteristic values ​​and vibration indices. All impact sequences are reconstructed into abnormal vibration data. The oscillation degree of the servo axis motion process is determined based on the abnormal vibration data. The oscillation degree is used to determine whether oscillation occurs during the servo axis movement process, and the servo gain of the drive unit is adjusted based on the determination result.

[0006] In some embodiments, decomposing the displacement sequence of the driving unit into multiple vibration sequences specifically includes: The displacement sequence of the driving unit is used as the original sequence, and all local extreme points in the original sequence are extracted. The maximum and minimum confluence feature lines of the original sequence are determined based on all local extrema. The center engagement sequence is determined based on the maximum engagement feature line and the minimum engagement feature line; The vibration frequency of the original sequence of the driving unit is extracted based on the center engagement degree sequence to obtain the vibration sequence and the residual sequence. The residual sequence is used as a new original sequence, and the above steps are repeated to obtain a new vibration sequence and a new residual sequence until the obtained residual sequence is a monotonic sequence, thereby obtaining multiple vibration sequences.

[0007] In some embodiments, determining the center engagement sequence based on the maximum engagement feature line and the minimum engagement feature line specifically includes: The center joint degree curve is determined based on the maximum joint feature line and the minimum joint feature line; The center junction curve is sampled at preset time intervals to obtain multiple center junctions, and then a center junction sequence is obtained.

[0008] In some embodiments, determining the transmission characteristic value of each vibration sequence specifically includes: Select a vibration sequence; Determine the length of this vibration sequence; The transmission characteristic value of the vibration sequence is determined based on all vibration data in the vibration sequence and the length of the vibration sequence. Continue to determine the transmission characteristic values ​​of the remaining vibration sequence.

[0009] In some embodiments, determining the vibration index of each vibration sequence specifically includes: Select a vibration sequence, divide the vibration sequence into multiple intervals according to a preset interval length, and determine the drive unit anomaly value of the vibration sequence under the preset interval length based on the vibration data in all intervals; Change the preset interval length, re-segment the vibration sequence, and determine the driving unit anomaly value of the vibration sequence under the changed interval length. Repeat the above steps until the number of interval lengths reaches the preset number of iterations, and then obtain the driving unit anomaly value of the vibration sequence under different interval lengths. The vibration index of the vibration sequence is determined based on all the abnormal values ​​of the driving units; Continue to determine the vibration index of the remaining vibration sequence.

[0010] In some embodiments, extracting multiple impact sequences from all vibration sequences using all transmission characteristic values ​​and vibration indices specifically includes: Determine the transmission characteristic threshold based on all transmission characteristic values; Vibration sequences with all transmission characteristic values ​​greater than the transmission characteristic threshold and vibration index less than the preset transmission characteristic threshold are taken as impact sequences.

[0011] In some embodiments, determining whether oscillation occurs during the servo axis motion process based on the oscillation degree specifically includes: The oscillation degree is compared with a preset oscillation threshold. When the oscillation degree is greater than the oscillation threshold, it is determined that oscillation has occurred during the servo axis motion process. When the oscillation degree is less than the oscillation threshold, it is determined that no oscillation occurred during the servo axis motion process.

[0012] Secondly, this application provides an automatic compensation CNC system, which includes a drive unit servo gain control unit, wherein the drive unit servo gain control unit includes: The acquisition module is used to acquire the displacement data of the drive unit during the movement of the servo axis and convert it into the displacement sequence of the drive unit; The processing module is used to decompose the displacement sequence of the drive unit into multiple vibration sequences and determine the transmission characteristic value and vibration index of each vibration sequence. The processing module is also used to extract multiple impact sequences from all vibration sequences through all transmission characteristic values ​​and vibration indexes, reconstruct all impact sequences into abnormal vibration data, and determine the oscillation degree of the servo axis motion process based on the abnormal vibration data; The adjustment module is used to determine whether oscillation occurs during the servo axis movement process based on the oscillation degree, and to adjust the servo gain of the drive unit according to the determination result.

[0013] Thirdly, this application provides a computer device, the computer device including a memory and a processor, the memory storing code, the processor being configured to acquire the code and execute the control method of the automatic compensation CNC system described in any of the preceding claims.

[0014] Fourthly, this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the control method of the automatic compensation CNC system described in any of the preceding claims.

[0015] The technical solutions provided by the embodiments disclosed in this application have the following beneficial effects: In this embodiment, the servo gain of the drive unit is adjusted based on the vibration of the drive unit, which can prevent oscillations in the servo axis motion caused by machining load disturbances or changes in mechanical state. Specifically, this application obtains the displacement sequence of the drive unit and decomposes it to obtain multiple vibration sequences of different frequencies, thereby determining the transmission characteristic value and vibration index of each vibration sequence. The transmission characteristic value measures the intensity of abnormal vibrations caused by sudden load changes or mechanical impacts in the corresponding frequency component; the vibration index measures the regularity of the vibration signal of that frequency component. The larger the vibration index, the more likely the sequence is random noise or non-periodic disturbance, rather than regular oscillations caused by specific mechanical faults. Multiple impact sequences are filtered from all vibration sequences using the transmission characteristic value and vibration index, thereby removing normal vibrations and random noise interference during servo axis motion and accurately extracting abnormal dynamic components caused by sudden changes in cutting force, mechanical transmission backlash, or resonance. All impact sequences are reconstructed into abnormal vibration data, and the oscillation degree is calculated from this abnormal vibration data. This oscillation degree reflects the frequency and intensity of abnormal impact events during the current motion. Large oscillations indicate significant vibrations in the machining process, potentially leading to surface chatter marks or dimensional deviations on the workpiece. The system uses this oscillation level to determine if the motion process is unstable and automatically adjusts (e.g., reduces) the servo gain to increase system damping and suppress oscillations upon detection. This method allows for proactive intervention in the early stages of disturbances, before they severely impact machining quality, thereby achieving smooth, high-precision servo axis movement under high dynamic loads. Attached Figure Description

[0016] Figure 1 This is a structural schematic diagram illustrating the working principle of a CNC system for implementing automatic compensation according to some embodiments of this application; Figure 2 This is an exemplary flowchart of a control method for an automatically compensated CNC system according to some embodiments of this application; Figure 3 This is an exemplary flowchart of a control method for determining the vibration index of each vibration sequence according to some embodiments of this application; Figure 4 This is a schematic diagram of exemplary hardware and / or software of a drive unit servo gain control unit according to some embodiments of this application; Figure 5 This is a schematic diagram of the structure of a computer device for implementing a control method of a numerical control system with automatic compensation according to some embodiments of this application. Detailed Implementation

[0017] The core of this application is to collect displacement data of the drive unit during the servo axis movement and convert it into a displacement sequence of the drive unit. The displacement sequence of the drive unit is then decomposed into multiple vibration sequences. The transmission characteristic value and vibration index of each vibration sequence are determined. Multiple impact sequences are extracted from all vibration sequences using all transmission characteristic values ​​and vibration indices. All impact sequences are reconstructed into abnormal vibration data. The oscillation degree of the servo axis movement process is determined based on the abnormal vibration data. The oscillation degree is used to determine whether oscillation occurs during the servo axis movement process. The servo gain of the drive unit is adjusted based on the determination result. By adjusting the servo gain of the drive unit based on the vibration condition of the drive unit, smooth movement of the servo axis can be achieved even when the drive unit is worn.

[0018] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0019] In some embodiments, reference Figure 1 This figure is a structural schematic diagram illustrating the working principle of a CNC system implementing automatic compensation according to some embodiments of this application. The automatic compensation CNC system includes a drive unit 101, a servo axis 102, a computer device 103, and a position sensor 104, which are described below: The drive unit 101 in this application is used to transmit the power of the servo motor to the servo axis. The drive unit can adjust the servo gain through the automatic compensation CNC system control method provided in this application so as to connect to the servo axis. Servo axis 102, in this application, refers to mechanical transmission components such as ball screws or spindles, used to convert the rotational motion of drive unit 101 into linear / rotational motion of worktable or tool; Controller 103, in this application, is used to adjust the servo gain of the drive unit through the automatic compensation CNC system control method provided in this application; Position sensor 104, in this application, is used to collect multiple position data of the drive unit of the servo axis during the motion process.

[0020] In some embodiments, reference Figure 2 The figure is an exemplary flowchart of a control method for an automatically compensated CNC system according to some embodiments of this application. The control method 200 of the automatically compensated CNC system mainly includes the following steps: In step 201, the displacement data of the drive unit during the servo axis motion is collected and converted into the displacement sequence of the drive unit.

[0021] In practice, displacement data of each drive unit at each time point during the motion of the servo axis can be collected by displacement sensors. The average value of the displacement data of all drive units is taken as the displacement data of the drive unit at that time point. The displacement data of all drive units are sorted in chronological order to obtain the displacement sequence of the drive units.

[0022] In step 202, the displacement sequence of the drive unit is decomposed into multiple vibration sequences, and the transmission characteristic value and vibration index of each vibration sequence are determined. In some embodiments, decomposing the displacement sequence of the driving unit into multiple vibration sequences can be achieved by the following steps: The displacement sequence of the driving unit is used as the original sequence, and all local extreme points in the original sequence are extracted. The maximum and minimum confluence feature lines of the original sequence are determined based on all local extrema. The center engagement sequence is determined based on the maximum engagement feature line and the minimum engagement feature line; The vibration frequency of the original sequence of the driving unit is extracted based on the center engagement sequence to obtain a vibration sequence and a residual sequence. The residual sequence is used as a new original sequence, and the above steps are repeated to obtain another vibrational sequence and a new residual sequence, until the obtained residual sequence is a monotonic sequence, thereby obtaining multiple vibrational sequences.

[0023] It should be noted that each vibration sequence in this application is a sequence that reflects the vibration of the drive unit at a certain vibration frequency. This vibration may be the vibration when the drive unit is working normally, or it may be abnormal vibration caused by sudden load change, tool chatter or mechanical transmission clearance, or it may be sampling error caused by other factors.

[0024] In some embodiments, the maximum and minimum binding feature lines of the original sequence are determined based on all local extrema. Specifically, cubic spline interpolation can be used to fit all local maxima points of all local extrema points into a curve, which is then used as the maximum binding feature line of the original sequence. Similarly, all local minima points of all local extrema points can be fitted into a curve, which is then used as the minimum binding feature line of the original sequence. In other embodiments, the maximum and minimum binding feature lines of the original sequence of the driving unit can also be determined using other existing technologies, which are not limited here.

[0025] It should be noted that, in this application, the maximum engagement feature line and the minimum engagement feature line refer to the upper and lower envelopes of the original sequence. The maximum engagement feature line reflects the characteristic of the drive unit vibration amplitude being the largest during the servo axis movement, and the minimum engagement feature line reflects the characteristic of the drive unit vibration amplitude being the smallest during the servo axis movement.

[0026] In some embodiments, determining the center engagement sequence based on the maximum and minimum engagement feature lines can be achieved using the following steps: The center joint degree curve is determined based on the maximum joint feature line and the minimum joint feature line; The center junction curve is sampled at preset time intervals to obtain multiple center junctions, and then a center junction sequence is obtained.

[0027] In a specific implementation, the average curve of the maximum and minimum bonding feature lines can be used as the center bonding degree curve.

[0028] It should be noted that the center engagement sequence in this application is a sequence used to reflect the changes in the vibration amplitude of the original sequence, and the center engagement sequence can reflect the frequency characteristics of the original sequence.

[0029] In some embodiments, extracting the vibration frequency of the original sequence of the driving unit based on the center engagement sequence to obtain a vibration sequence and a residual sequence at a vibration frequency can be achieved by the following steps: Obtain the center cohesion sequence; Obtain the original sequence; The vibration sequence is determined based on the central engagement sequence and the original sequence; The residual sequence is determined based on the vibration sequence and the original sequence, wherein the vibration sequence and the residual sequence can be determined according to the following formula: in, For the first A vibrational sequence For the first One original sequence, For the first A sequence of central affinity, For the first A residual sequence.

[0030] It should be noted that, in this application, by collecting the displacement sequence of the drive unit during the motion of the servo axis, the vibration of the drive unit during the motion of the servo axis can be obtained, and by performing vibration frequency decomposition on the displacement sequence, the vibration characteristics at different frequencies in the displacement sequence can be determined.

[0031] In some embodiments, determining the transmission characteristic value of each vibration sequence can be achieved by the following steps: Select a vibration sequence; Determine the length of this vibration sequence; The transmission characteristic value of the vibration sequence is determined based on all vibration data in the vibration sequence and the length of the vibration sequence. Continue to determine the transmission characteristic values ​​of the remaining vibration sequence.

[0032] The transmission characteristic value can be determined according to the following formula: in, For the first Transmission characteristic values ​​of a vibration sequence, For the first The first vibration sequence in the vibration sequence Vibration data, For the first The first vibration sequence in the vibration sequence Vibration data, For the first The length of a vibration sequence.

[0033] It should be noted that the transmission characteristic value in this application is a parameter used to measure the degree of influence caused by the abnormal impact of the servo axis drive unit during movement in the vibration sequence at the corresponding frequency. The larger the transmission characteristic value, the more the corresponding vibration sequence contains the influence caused by the abnormal impact of the servo axis drive unit during movement. The information of the abnormal impact of the drive unit during movement can be extracted by the transmission characteristic value.

[0034] refer to Figure 3 The figure is an exemplary flowchart of a control method for determining the vibration index of each vibration sequence according to some embodiments of this application, which is described in detail below: In step 2021, a vibration sequence is selected, and the vibration sequence is divided into multiple intervals according to a preset interval length. The abnormal value of the driving unit of the vibration sequence under the preset interval length is determined based on the vibration data in all intervals. In step 2022, the preset interval length is changed, the vibration sequence is re-divided, and the driving unit variation value of the vibration sequence under the changed interval length is determined. The above steps are repeated until the number of interval lengths reaches the preset number of iterations, thereby obtaining the driving unit variation value of the vibration sequence under different interval lengths. In step 2023, the vibration index of the vibration sequence is determined based on all the abnormal values ​​of the drive units; In step 2024, the vibration index of the remaining vibration sequence is determined.

[0035] It should be noted that the preset interval length in this application can be preset according to the length of the vibration sequence. In specific implementation, the interval length can be preset to 1 / 3 of the vibration sequence length, that is, the vibration sequence is divided into 3 intervals on average. When changing the preset interval length, the changed interval length can also be preset to 1 / 5 of the vibration sequence length, that is, the vibration sequence is divided into 5 intervals on average. In other embodiments, other interval lengths can also be preset to divide the vibration sequence, which is not limited here.

[0036] It should be noted that the larger the number of iterations preset in this application, the more accurate the vibration index will be. In specific implementation, the number of iterations can be preset to 10. In other embodiments, the number of iterations can also be preset to other values, which are not limited here.

[0037] In some embodiments, determining the drive unit variation value of a vibration sequence within a preset interval length based on vibration data across all intervals can be achieved using the following steps: The vibration center data for each interval is determined based on the vibration data within each interval. Determine the upper and lower limits of data deviation for each interval based on the vibration center data for each interval; The driving unit anomaly value for this vibration sequence is determined based on the vibration center data, upper limit of data deviation, and lower limit of data deviation for all intervals. The driving unit anomaly value can be determined using the following formula: in, For the first A vibration sequence with an interval length of abnormal values ​​of the drive unit at that time. The number of intervals, The interval length is... For the first In the vibration sequence, the th ... The first interval Vibration data, For the first In the vibration sequence, the th ... Vibration center data for each interval, For the first In the vibration sequence, the th ... The data in each interval deviates from the upper limit. For the first In the vibration sequence, the th ... The data in each interval deviates from the lower limit. It represents the logarithm to the base 10.

[0038] It should be noted that the driving unit anomaly value in this application is a value used to measure the degree of abnormal vibration in the vibration sequence. The larger the driving unit anomaly value, the greater the degree of abnormal vibration in the corresponding vibration sequence.

[0039] In practice, the average value of all vibration data within each interval can be determined, and this average value can be used as the vibration center data for the corresponding interval.

[0040] In some embodiments, determining the upper and lower limits of data deviation for a given interval based on the vibration center data for each interval can be achieved in the following manner: For each interval, determine the data deviation corresponding to each vibration data point within that interval; The maximum data deviation within the interval is taken as the upper limit of data deviation, and the minimum data deviation within the interval is taken as the lower limit of data deviation. This is used to determine the upper and lower limits of data deviation for all intervals. The data deviation can be determined using the following formula: in, For the first In the vibration sequence, the th ... The first interval The data deviation corresponding to each vibration data point For the first In the vibration sequence, the th ... The first interval Vibration data, For the first In the vibration sequence, the th ... Vibration center data for each interval.

[0041] In some embodiments, the vibration index of a vibration sequence can be determined based on the drive unit variation values ​​across all interval lengths in the vibration sequence, which can be achieved in the following manner: By performing curve fitting on all interval lengths and all driving unit anomaly values ​​of the vibration sequence, the interval length-anomaly value curve is obtained; The vibration index of the vibration sequence is determined based on the interval length-anomaly value curve.

[0042] In practice, the abnormal values ​​of the driving units can be used as the vertical axis and the natural logarithm of the interval length can be used as the horizontal axis. All the abnormal values ​​of the driving units and the natural logarithm of the interval length can be fitted into a curve of a linear function, and this curve can be used as the interval length-abnormal value curve.

[0043] In addition, in practical implementation, the slope of the interval length minus the anomaly value curve of each vibration sequence can be used as the vibration index of the corresponding vibration sequence.

[0044] It should be noted that the vibration index mentioned in this application is a parameter used to measure the degree of vibration of a vibration sequence at a given frequency. The vibration index is usually between 0 and 1. The larger the vibration index, the lower the degree of vibration of the corresponding vibration sequence, and the more likely the vibration sequence is to be erroneous information caused by noise or sampling error.

[0045] It should be noted that, in this application, by extracting the transmission feature value of each vibration sequence, the degree of influence caused by the vibration of the drive unit containing the servo axis at the moment of motion in each vibration sequence can be obtained, which facilitates the subsequent extraction of the required information. By extracting the vibration index of each vibration sequence, the degree of oscillation of each vibration sequence can be obtained. The vibration sequence of the drive unit corresponding to the smaller vibration index is usually erroneous information caused by noise or sampling error. By extracting the vibration index of each vibration sequence, it is easier to remove these error effects in the subsequent process, thereby improving the accuracy of vibration extraction of the servo axis drive unit.

[0046] In step 203, multiple impact sequences are extracted from all vibration sequences using all transmission characteristic values ​​and vibration indices. All impact sequences are reconstructed into abnormal vibration data, and then the oscillation degree of the servo axis motion process is determined based on the abnormal vibration data.

[0047] In some embodiments, extracting multiple impact sequences from all vibration sequences using all transmission characteristic values ​​and vibration indices can be achieved through the following steps: Determine the transmission characteristic threshold based on all transmission characteristic values; Vibration sequences with all transmission characteristic values ​​greater than the transmission characteristic threshold and vibration index less than the preset vibration threshold are taken as impact sequences.

[0048] It should be noted that the vibration index in this application is usually between 0 and 1. The vibration intensity of a vibration sequence with a vibration index greater than 0.5 is significantly different from that of a vibration sequence with a vibration index less than 0.5. Therefore, the vibration threshold can be preset to 0.5.

[0049] In practice, the average value of all transmission characteristic values ​​can be used as the transmission characteristic threshold.

[0050] In practice, the impact sequences of all driving units can be added together, and the resulting sequence can be used as abnormal vibration data.

[0051] In some embodiments, determining the oscillation degree of the servo axis motion process based on the abnormal vibration data can be achieved through the following steps: By determining the absolute value of each data point in the abnormal vibration data, multiple positive oscillation values ​​are obtained; The positive oscillation value that is simultaneously greater than the adjacent positive oscillation values ​​is taken as the peak value of the servo axis oscillation; The oscillation degree is determined by the oscillation peak values ​​of all servo axes.

[0052] In practice, the number of oscillation peaks of the servo axis can be used as the oscillation degree.

[0053] It should be noted that the oscillation degree in this application is a parameter used to measure the degree of abnormal vibration of the drive unit during the movement of the drive unit due to load disturbance or dynamic mismatch when the servo axis moves (such as start, stop, or change direction). The larger the oscillation degree, the greater the degree of abnormal vibration generated during the movement of the drive unit. It is necessary to appropriately reduce the servo gain of the drive unit to achieve half transmission and avoid machine tool oscillation during the servo axis shifting process.

[0054] It should be noted that in this application, by extracting multiple impact sequences from all vibration sequences, the normal vibration and error interference of the servo axis drive unit during the motion process are removed, and the abnormal dynamics caused by sudden load changes or mechanical resonance are extracted, which facilitates the automatic compensation control of the servo axis drive unit in subsequent steps.

[0055] In step 204, the oscillation degree is used to determine whether oscillation occurs during the servo axis movement process, and the servo gain of the drive unit is adjusted according to the determination result.

[0056] In some embodiments, determining whether oscillation occurs during the servo axis motion process based on the oscillation degree can be achieved using the following steps: The oscillation degree is compared with a preset oscillation threshold. When the oscillation degree is greater than the oscillation threshold, it is determined that oscillation has occurred during the servo axis motion process. When the oscillation degree is less than the oscillation threshold, it is determined that no oscillation occurred during the servo axis motion process.

[0057] In practice, the servo axis can be run under various typical machining conditions (such as different cutting parameters and different axial loads), and the minimum oscillation degree corresponding to when the machining surface quality begins to deteriorate or when the system exhibits observable oscillation is calibrated as the oscillation threshold.

[0058] In some embodiments, adjusting the servo gain of the drive unit based on the determination result can be achieved by the following steps: When the judgment result indicates that oscillation occurs during the servo axis movement, the control reduces the servo gain of the drive unit and re-judges whether oscillation occurs during the servo axis movement until the judgment result indicates that no oscillation occurs during the servo axis movement.

[0059] It should be noted that in this application, irrelevant information is removed from the displacement sequence of the drive unit to obtain abnormal dynamic data containing only those caused by load disturbances or dynamic mismatches. Each peak in this data represents a significant abnormal impact event. By comparing the number of peaks with a preset oscillation threshold, when the number of peaks exceeds the threshold, it indicates that the system's current damping is insufficient or the disturbance is too strong. By reducing the servo gain to decrease the system response bandwidth and gain, oscillation is suppressed, thus realizing a control method for automatic compensation of the servo axis.

[0060] Furthermore, in another aspect of this application, in some embodiments, this application provides an automatically compensated CNC system, wherein the servo axis includes a drive unit and a servo gain control unit, referencing... Figure 4 The figure is a schematic diagram of exemplary hardware and / or software of a drive unit servo gain control unit 400 according to some embodiments of this application. The drive unit servo gain control unit 400 includes: a data acquisition module 401, a processing module 402, and an adjustment module 403, which are described below: The acquisition module 401 in this application is mainly used to acquire the displacement data of the drive unit during the motion of the servo axis and convert it into the displacement sequence of the drive unit. Processing module 402, in this application, is mainly used to decompose the displacement sequence of the driving unit into multiple vibration sequences and determine the transmission characteristic value and vibration index of each vibration sequence. It should be noted that the processing module 403 in this application is also used to extract multiple impact sequences from all vibration sequences through all transmission characteristic values ​​and vibration indexes, reconstruct all impact sequences into abnormal vibration data, and determine the oscillation degree of the servo axis motion process based on the abnormal vibration data; The adjustment module 403 in this application is mainly used to determine whether oscillation occurs during the motion of the servo axis based on the oscillation degree, and to adjust the servo gain of the drive unit according to the determination result.

[0061] In addition, this application also provides a computer device, the computer device including a memory and a processor, the memory storing code, and the processor being configured to acquire the code and execute the above-described control method for an automatically compensated numerical control system.

[0062] In some embodiments, reference Figure 5 The figure is a schematic diagram of the structure of a computer device for implementing a control method for an automatically compensated CNC system according to some embodiments of this application. The control method for the automatically compensated CNC system in the above embodiments can be achieved through… Figure 5The computer device shown is used to implement this, and the computer device 500 includes at least one processor 501, a communication bus 502, a memory 503, and at least one communication interface 504.

[0063] The processor 501 may be a general-purpose central processing unit (CPU), an application-specific integrated circuit (AIC), or one or more control methods for controlling the execution of the automatic compensation CNC system in this application.

[0064] The communication bus 502 may include a path for transmitting information between the aforementioned components.

[0065] Memory 503 may be a read-only memory (ROM) or other type of static storage device capable of storing static information and instructions, random access memory (RAM) or other type of dynamic storage device capable of storing information and instructions, or electrically erasable programmable read-only memory (EEPROM), compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical discs, laser discs, optical discs, digital universal optical discs, Blu-ray discs, etc.), magnetic disks or other magnetic storage devices, or any other medium capable of carrying or storing desired program code in the form of instructions or data structures and accessible by a computer, but not limited thereto. Memory 503 may exist independently and be connected to processor 501 via communication bus 502. Memory 503 may also be integrated with processor 501.

[0066] The memory 503 stores program code for executing the scheme of this application, and its execution is controlled by the processor 501. The processor 501 executes the program code stored in the memory 503. The program code may include one or more software modules. The control method of the automatically compensated CNC system in the above embodiments can be implemented by the processor 501 and one or more software modules in the program code in the memory 503.

[0067] Communication interface 504 uses any transceiver-like device to communicate with other devices or communication networks, such as Ethernet, radio access network (RAN), wireless local area network (WLAN), etc.

[0068] In a specific implementation, as one example, a computer device may include multiple processors, each of which may be a single-core (single-CPU) processor or a multi-core (multi-CPU) processor. Here, a processor may refer to one or more devices, circuits, and / or processing cores used to process data (e.g., computer program instructions).

[0069] The aforementioned computer device can be a general-purpose computer device or a special-purpose computer device. In specific implementations, the computer device can be a desktop computer, a portable computer, a network server, a handheld digital assistant (PDA), a mobile phone, a tablet computer, a wireless terminal device, a communication device, or an embedded device. This application does not limit the type of computer device.

[0070] In addition, this application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described automatic compensation control method for a numerical control system.

[0071] In summary, the automatically compensated CNC system and its control method disclosed in this application adjust the servo gain of the drive unit based on the vibration of the drive unit, thus avoiding oscillations during servo axis shifting caused by wear of the drive unit. Specifically, this application obtains the displacement sequence of the drive unit and decomposes it to obtain multiple vibration sequences, thereby determining the transmission characteristic value and vibration index of each vibration sequence. The transmission characteristic value is a parameter used to measure the degree of influence caused by abnormal impacts from the drive unit of the servo axis during movement in the vibration sequence at the corresponding frequency. The vibration index is a parameter used to measure the degree of vibration in the vibration sequence at the corresponding frequency. The larger the vibration index, the more likely the corresponding vibration sequence is erroneous information caused by noise or sampling errors. Transmission characteristic values ​​and vibration indexes remove normal vibrations and error interference from multiple impact sequences in all vibration sequences, obtaining abnormal dynamics caused by sudden load changes or mechanical resonance. All impact sequences are reconstructed into abnormal vibration data, and then the oscillation degree is extracted from this abnormal vibration data. This oscillation degree refers to the number of times the drive unit is subjected to severe impacts during the servo axis movement. When the oscillation degree is large, the machining process will oscillate or even cause machining interruption. By using the oscillation degree, it is determined whether oscillation will occur in the current servo axis movement process. When the machine tool is found to be oscillating, the servo gain of the drive unit is reduced in time to avoid oscillation in the machine tool machining process. This enables smooth movement of the servo axis with low disturbance of the drive unit.

[0072] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0073] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of the invention. Therefore, if these modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include these modifications and variations.

Claims

1. A control method for an automatically compensated numerical control system, characterized in that, Includes the following steps: The displacement data of the drive unit during the servo axis motion is collected and converted into a displacement sequence of the drive unit; The displacement sequence of the drive unit is decomposed into multiple vibration sequences, and the transmission characteristic value and vibration index of each vibration sequence are determined. Multiple impact sequences are extracted from all vibration sequences using all transmission characteristic values ​​and vibration indices. All impact sequences are reconstructed into abnormal vibration data, and then the oscillation degree of the servo axis motion process is determined based on the abnormal vibration data. The oscillation degree is used to determine whether oscillation occurs during the servo axis movement process, and the servo gain of the drive unit is adjusted based on the determination result.

2. The method according to claim 1, characterized in that, Decomposing the displacement sequence of the driving unit into multiple vibration sequences specifically includes: The displacement sequence of the driving unit is used as the original sequence, and all local extreme points in the original sequence are extracted. The maximum and minimum confluence feature lines of the original sequence are determined based on all local extrema. The center engagement sequence is determined based on the maximum engagement feature line and the minimum engagement feature line; The vibration frequency of the original sequence of the driving unit is extracted based on the center engagement degree sequence to obtain the vibration sequence and the residual sequence. The residual sequence is used as a new original sequence, and the above steps are repeated to obtain a new vibration sequence and a new residual sequence until the obtained residual sequence is a monotonic sequence, thereby obtaining multiple vibration sequences.

3. The method according to claim 2, characterized in that, Determining the center engagement sequence based on the maximum and minimum engagement feature lines specifically includes: The center joint degree curve is determined based on the maximum joint feature line and the minimum joint feature line; The center junction curve is sampled at preset time intervals to obtain multiple center junctions, and then a center junction sequence is obtained.

4. The method according to claim 1, characterized in that, Determining the transmission characteristic values ​​of each vibration sequence specifically includes: Select a vibration sequence; Determine the length of this vibration sequence; The transmission characteristic value of the vibration sequence is determined based on all vibration data in the vibration sequence and the length of the vibration sequence. Continue to determine the transmission characteristic values ​​of the remaining vibration sequence.

5. The method according to claim 1, characterized in that, Determining the vibration index for each vibration sequence specifically includes: Select a vibration sequence, divide the vibration sequence into multiple intervals according to a preset interval length, and determine the drive unit anomaly value of the vibration sequence under the preset interval length based on the vibration data in all intervals; Change the preset interval length, re-segment the vibration sequence, and determine the driving unit anomaly value of the vibration sequence under the changed interval length. Repeat the above steps until the number of interval lengths reaches the preset number of iterations, and then obtain the driving unit anomaly value of the vibration sequence under different interval lengths. The vibration index of the vibration sequence is determined based on all the abnormal values ​​of the driving units; Continue to determine the vibration index of the remaining vibration sequence.

6. The method according to claim 1, characterized in that, Multiple impact sequences were extracted from all vibration sequences using all transmission characteristic values ​​and vibration indices, specifically including: Determine the transmission characteristic threshold based on all transmission characteristic values; Vibration sequences with all transmission characteristic values ​​greater than the transmission characteristic threshold and vibration index less than the preset transmission characteristic threshold are taken as impact sequences.

7. The method according to claim 1, characterized in that, Determining whether oscillation occurs during the servo axis motion process based on the oscillation degree specifically includes: The oscillation degree is compared with a preset oscillation threshold. When the oscillation degree is greater than the oscillation threshold, it is determined that oscillation has occurred during the servo axis motion process. When the oscillation degree is less than the oscillation threshold, it is determined that no oscillation occurred during the servo axis motion process.

8. An automatic compensation CNC system, characterized in that, The drive unit servo gain control unit includes: The acquisition module is used to acquire the displacement data of the drive unit during the movement of the servo axis and convert it into the displacement sequence of the drive unit; The processing module is used to decompose the displacement sequence of the drive unit into multiple vibration sequences and determine the transmission characteristic value and vibration index of each vibration sequence. The processing module is also used to extract multiple impact sequences from all vibration sequences through all transmission characteristic values ​​and vibration indexes, reconstruct all impact sequences into abnormal vibration data, and then determine the oscillation degree of the servo axis motion process based on the abnormal vibration data. The adjustment module is used to determine whether oscillation occurs during the servo axis movement process based on the oscillation degree, and to adjust the servo gain of the drive unit according to the determination result.

9. A computer device, characterized in that, The computer device includes a memory and a processor, the memory storing code, and the processor being configured to retrieve the code and execute the control method of the automatically compensated numerical control system as described in any one of claims 1 to 7.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the control method of the automatic compensation numerical control system as described in any one of claims 1 to 7.

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