A laser cutting-based visual measurement calibration method, system and terminal

Abstract

The application provides a kind of vision measurement calibration method, system and calibration terminal based on laser cutting, it is related to laser cutting technical field, adjust lens and camera physical hardware parameters on laser cutting machine, make definition meet preset definition threshold value;Control laser head of laser cutting machine returns zero point;The preset point of calibration plate is aligned with laser red light spot, executes shooting process, obtains original first image;Rotating machine tool is preset angle, obtains the correction information of rotation angle to first image, also obtains the second image of actual positive matching of machine tool;Positioning edge finding is carried out, obtains the actual deviation of each side coordinate after edge finding and machine tool mechanical coordinate, actual deviation is included into compensation value;Other areas outside the center point of second image are subjected to mechanical coordinate dynamic compensation, so that the compensated mechanical coordinate meets calibration requirements.The application can establish correlation mapping between visual image and real physical environment, so as to locate the key points of plate processing, meet the calibration requirements.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of laser cutting technology, in particular to a visual measurement calibration method and system based on laser cutting and a calibration terminal. BACKGROUND

[0002] Laser cutting uses a high-power density laser beam to irradiate the material to be cut, which quickly heats the material to the vaporization temperature, evaporates to form a hole, and as the beam moves on the material, the hole continuously forms a narrow cut seam, completing the cutting of the material.

[0003] The common processing method in the laser cutting industry is that a drawing is designed by a drawing designer according to the size and style of the plate to be processed, the drawing is imported into the cutting machine before processing, and then the starting point of the plate is positioned by manual edge searching, and finally the processing operation is performed. The above operation steps are complicated, and the manual operation is large, which is not easy to automate and process in large quantities. SUMMARY

[0004] The present application provides a visual measurement calibration method based on laser cutting, which uses a visual system to establish a correlation mapping between visual images and real physical environments through a simple calibration method, thereby measuring objects in the real environment with images to meet the requirements of laser cutting.

[0005] The visual measurement calibration method based on laser cutting comprises:

[0006] S101, adjusting the lens and camera physical hardware parameters of the laser cutting machine, so that the imaging clarity of the lens and camera meets the preset clarity threshold;

[0007] S102, controlling the laser head of the laser cutting machine to return to zero;

[0008] S103, pre-preparing a calibration plate, controlling the laser head to move along the X-axis and Y-axis of the machine tool, aligning the preset points of the calibration plate with the laser red light spot, executing the shooting process, so that the camera can shoot the machine tool surface, and obtaining the original first image, and executing the calibration process;

[0009] S104, obtaining the machine tool coordinate information through the pre-prepared machine tool reference point and the preset point of the calibration plate, rotating the machine tool by a preset angle, obtaining the rotation angle, and correcting the first image, and also obtaining the second image matched in the actual positive direction of the machine tool;

[0010] S105, analyzing the coordinates of the image center point based on the second image matched in the actual positive direction of the machine tool, positioning and searching the edges in the preset direction according to the coordinates of the center point of the second image, obtaining the actual deviation of each edge coordinate after searching the edges from the machine tool mechanical coordinate, and counting the actual deviation into the compensation value;

[0011] S106, dynamically compensating the mechanical coordinates of other regions except the second image center point, so that the compensated mechanical coordinates meet the calibration requirements.

[0012] It should be further explained that in step S101, the lens is fixedly installed on the preset position of the camera, the lens aperture is adjusted, and the imaging brightness is adjusted to the preset brightness threshold.

[0013] It should be further explained that step S101 further comprises adjusting the focal length of the lens so that the sharpness of the object in the image reaches the preset sharpness threshold.

[0014] It should be further explained that in step S102, the zero point regression process is started, and then the laser head is controlled to move along the X, Y and Z axes of the machine tool, and the sensing signal of the machine tool during movement is confirmed. When the signal disappears, the coordinates are marked.

[0015] It should be further explained that in step S103, the pre-prepared calibration plate comprises a substrate provided on the bottom layer and a color block with calibration on the upper layer, and one end point of the substrate overlaps one end point of the color block and is fixed.

[0016] The color block is rotated to form a preset angle between the color block and the substrate.

[0017] Based on the calibration plate, the first point calibration process and the second point calibration process are performed, so that the camera can shoot the machine tool surface, and the color block region of the calibration plate in the image of the machine tool surface is selected, and the calibration program is completed.

[0018] It should be further explained that step S104 further comprises that the slope corresponding to the left edge of the color block in the calibration plate and the rotation angle offset are calculated by the Pythagorean theorem and the arctangent trigonometric function, in the following manner:

[0019] dK=(p2.y-p1.y) / (p2.x-p1.x)

[0020] dRad=arctan(dK)

[0021] Wherein, p1.x, p1.y are the image coordinates X and Y of the first calibration plate corner point, respectively, and p2.x, p2.y are the image coordinates X and Y of the second calibration plate corner point, respectively, dK is the calculated slope, and dRad is the rotation angle offset value.

[0022] The obtained rotation angle is corrected for the second image, and the second image is obtained by inverse rotation, which is actually matched with the machine tool in the forward direction.

[0023] It is further explained that, the step S106 further comprises: compensating other regions except the second image center point, and the compensation mode is that the compensation direction of the first quadrant of the mechanical coordinates involved in the second image is X negative direction and Y negative direction, the compensation direction of the second quadrant of the mechanical coordinates is X negative direction and Y positive direction, the compensation direction of the third quadrant of the mechanical coordinates is X positive direction and Y negative direction, and the compensation direction of the fourth quadrant of the mechanical coordinates is X positive direction and Y positive direction.

[0024] It is further explained that, the compensation value is calculated by the following way:

[0025]

[0026] Wherein, a0 is an inner product constant, a n is a frequency domain cosine component amplitude, b n is a frequency domain sine component amplitude, n is a general parameter, and x is the distance of the compensation point from the center point.

[0027] The application further provides a calibration system for long-distance visual measurement, which comprises a hardware definition module, a regression zero point control module, a shooting processing module, an image correction module, a deviation compensation module and a dynamic compensation module.

[0028] The hardware definition module is used for adjusting the physical hardware parameters of the lens and the camera on the laser cutting machine, so that the imaging definition of the lens and the camera meets the preset definition threshold.

[0029] The regression zero point control module is used for controlling the head regression zero point of the laser cutting machine.

[0030] The shooting processing module is used for the prefabricated calibration plate, controls the movement of the machine tool, aligns the preset points of the calibration plate with the laser red light spots, executes the shooting process, and enables the camera to shoot the machine tool surface and execute the calibration process.

[0031] The image correction module is used for deriving the machine tool coordinate state through the prefabricated machine tool reference points and the preset points of the calibration plate, rotating the machine tool by a preset angle, deriving the rotation angle correction information of the image, and deriving the actual forward matching image of the machine tool.

[0032] The deviation compensation module is used for analyzing the coordinates of the image center point based on the actual forward matching image of the machine tool, positioning and searching the edges in the preset direction according to the coordinates of the image center point, obtaining the actual deviation of each edge coordinate after searching the edges from the machine tool mechanical coordinates, and counting the actual deviation into the compensation value.

[0033] The dynamic compensation module is used for dynamically compensating the mechanical coordinates of other regions except the image center point, so that the compensated mechanical coordinates meet the calibration requirements.

[0034] The present invention also provides a calibration terminal, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of a laser-cut-based visual measurement calibration method.

[0035] As can be seen from the above technical solutions, the present invention has the following advantages:

[0036] The laser-cut-based visual measurement calibration method provided by this invention simplifies the operation for operators, making it more user-friendly, easy to implement, and convenient, thus improving calibration efficiency. Furthermore, since the calibration board is manually placed, it cannot be guaranteed to be centered in the camera's field of view. Errors caused by placement are calculated and compensated for through the calibration method, making operation simple and easy to complete. The calibration logic is more stable and has lower coupling. The calibration board is easy to manufacture, does not require particularly demanding reflective materials, and uses a mother-daughter board system, riveted together, which is more ergonomic during operation. There is no mutual interference between the two calibration points. When calibrating the second point, the base plate does not need to be moved; simply rotating the color block around the rivet completes the calibration process. This invention can summarize calibration information, facilitating access for processing and monitoring personnel, effectively improving the efficiency of calibration process monitoring. It improves the accuracy and precision of workpiece calibration, thereby achieving timely and scientific supervision, management, and control of the entire calibration process. Attached Figure Description

[0037] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the description will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 The flowchart shows a vision measurement calibration method based on laser cutting.

[0039] Figure 2 This is a schematic diagram of the camera relative to the machine tool proposed in this invention;

[0040] Figure 3 This invention provides a calibration board model for calibration.

[0041] Figure 4 This is the relative image reference field of view of the calibration plate in this invention. Detailed Implementation

[0042] The laser cutting-based visual measurement and calibration method provided by this invention aims to automate the long-distance visual measurement and calibration process. Combined with a vision system, it can establish a correlation mapping between visual images and the real physical environment through a prefabricated calibration plate, thereby using images to measure objects in the real environment. Moreover, after image processing, it can directly output processing drawings and locate the processing start point of the plate, reducing human intervention and facilitating fully automated production line processing.

[0043] The laser-cut-based visual measurement calibration method can acquire and process related parameters using artificial intelligence technology during execution. Specifically, this method utilizes a digital computer or an industrial control computer configured on the laser cutting machine to simulate, extend, and expand human intelligence, perceiving the environment, acquiring knowledge, and using that knowledge to obtain optimal results. It encompasses theories, methods, technologies, and application devices.

[0044] In this way, the vision measurement calibration method based on laser cutting utilizes the top camera 1 and lens of the laser cutting machine, and through image processing, sensor monitoring, data transmission and other technologies, realizes real-time interactive mapping between the machine tool 2 and vision measurement, thereby realizing the vision measurement calibration process. Moreover, the calibration process is easy to operate, easy to implement in products, and easy for operators to use.

[0045] like Figure 1 A flowchart illustrating a preferred embodiment of the laser-cut-based visual measurement calibration method of the present invention is shown. The laser-cut-based visual measurement calibration method is applied to one or more calibration terminals. These calibration terminals can be used in conjunction with a laser cutting machine and are devices capable of automatically performing numerical calculations and / or information processing according to pre-set or stored instructions. Their hardware includes, but is not limited to, microprocessors, application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), digital signal processors (DSPs), embedded devices, etc.

[0046] The network where the terminal is located includes, but is not limited to, the Internet, wide area network, metropolitan area network, local area network, and virtual private network (VPN).

[0047] The visual measurement calibration method based on laser cutting of the present invention is applied to the calibration analysis of visual measurement before laser cutting machine cutting. It analyzes the visual measurement status and, after calibration by the visual measurement calibration method of the present invention, enables the visual measurement of laser cutting machine to meet the cutting requirements.

[0048] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0049] Please see Figure 1 The diagram shows a flowchart of a vision measurement calibration method based on laser cutting in a specific embodiment. The method includes:

[0050] S101. Adjust the physical hardware parameters of the lens and camera 1 on the laser cutting machine so that the imaging clarity of the lens and camera 1 meets the preset clarity threshold.

[0051] In this embodiment, the operator can install the lens and camera 1 onto the laser cutting machine and adjust the aperture-related parameters of the camera 1, such as the focal length, image brightness, grayscale, and sharpness of the camera 1, so that the image sharpness of the camera 1 meets the preset sharpness threshold.

[0052] For example, the adjustment method can be to fix the lens on camera 1, and then adjust the aperture to adjust the image brightness to a larger value according to the installation position of the workpiece on the laser cutting machine, and then adjust the focus to adjust the workpiece in the image to the clearest position. You can first rotate quickly, and when you find that the clearest position has been adjusted, you can reverse slowly to basically ensure that it stops at the clearest point.

[0053] S102, Control the laser cutting machine head to return to zero;

[0054] Specifically, after the laser cutting machine is manufactured and installed, or after the laser cutting machine is shut down and restarted, or before starting a new process after completing the current cutting process, it is necessary to refresh the information and shut down and restart. This requires zero-point return of the laser cutting machine. Here, the operator can click the zero-point return button, select all zero-point return, and the machine tool 2 will first perform Z-axis positioning, searching for the reference signal in the negative direction. After the signal is sensed, it will approach the reference signal in the opposite direction at a low speed. After the signal disappears, the starting position of the Z-axis is marked and the coordinates are marked.

[0055] Similarly, for Y-axis positioning, a reference signal is sought in the negative direction. After the signal is detected, the system approaches slowly in the opposite direction. Once the signal disappears, the starting position of the Y-axis is determined, and the coordinates are marked. Finally, X-axis positioning is performed, and the coordinates are marked. After each phase of motion is completed, the laser cutting machine system automatically calibrates and zeroes.

[0056] S103, a pre-made calibration plate, controls the movement of machine tool 2, aligns the preset points of the calibration plate with the laser red light spot, executes the shooting process, enables camera 1 to capture the surface of machine tool 2, and executes the calibration process;

[0057] According to embodiments of this application, a prefabricated calibration plate is used as a reference. Figure 3 The calibration plate has a two-layer structure. The bottom layer is a base plate 3, and the upper layer has a color block plate 4 for calibration. The base plate 3 and the color block plate 4 are connected together by a rivet, so the color block plate 4 can rotate around the rivet. The rivet is located at one corner of the color block plate 4. Color blocks 5 are arranged on the color block plate 4.

[0058] The first point calibration uses the first move command to move the laser cutting machine tool 2 to the predetermined first point coordinate position, and then aligns the first point of the calibration plate, which can be the point at the rivet position, with the laser red light spot.

[0059] The second point calibration uses the second move command to move the laser cutting machine tool 2 to the predetermined second point coordinate position, and then gently rotate the color block plate 4 to align the second point, which can be the second corner of the color block in a clockwise direction, with the laser red light spot.

[0060] After the above operations are completed, the shooting area can be displayed on the screen, allowing camera 1 to capture the entire area of ​​machine tool 2 within its field of view. Then, proceed to the calibration stage, displaying the image captured by camera 1. Select the color patch 4 area on the calibration board in the image, ensuring that the sharpness meets the preset sharpness threshold.

[0061] For example, the position of the calibration plate in the image captured by camera 1 is referenced. Figure 4 The outer rectangle represents the field of view of camera 1, and the small gray rectangle inside represents the position of the calibration plate.

[0062] S104. Obtain the machine tool coordinate information through the pre-made machine tool 2 reference point and the preset point of the calibration plate, rotate the machine tool by a preset angle to obtain the rotation angle, correct the first image, and also obtain the second image of the actual positive matching of the machine tool.

[0063] In this embodiment, the coordinates of each point of the color block corresponding to the machine tool 2 can be obtained through the pre-made machine tool 2 reference points and calibration plate information, such as the proportional reference values ​​of the X and Y directions. The size of the color block can be set according to the calibration needs. The linear proportion of the pixel size of the color block can be obtained through the camera 1.

[0064] Since the calibration plate is at an angle relative to the horizontal line, the slope of the right-angled side of the calibration plate is calculated using the Pythagorean theorem and arctangent trigonometric functions. Specifically, it can be calculated using the following formula.

[0065] dK = (p2.y - p1.y) / (p2.x - p1.x)

[0066] dRad = arctan(dK)

[0067] Where p1.x and p1.y are the image coordinates X and Y of the corner point of the first calibration plate, p2.x and p2.y are the image coordinates X and Y of the corner point of the second calibration plate, dK is the calculated slope, and dRad is the rotation angle offset value;

[0068] The obtained rotation angle is used to correct the second image, and then the image is rotated in the opposite direction to obtain a second image that matches the actual forward orientation of the machine tool.

[0069] S105. Based on the coordinates of the center point of the second image of the actual positive matching of the machine tool 2, perform positioning and edge finding in the preset direction according to the coordinates of the center point of the second image, obtain the actual deviation between the coordinates of each edge after edge finding and the mechanical coordinates of the machine tool 2, and include the actual deviation in the compensation value.

[0070] It is understood that after obtaining the second image that is actually positively matched with the machine tool 2, the present invention obtains the center point of the mechanical coordinates, which are the coordinates involved in the X-axis, Y-axis, and Z-axis mentioned above. The workpiece is placed at the center point of the second image, and its positioning and edge finding are performed. The positioning and edge finding method can adopt the positioning and edge finding method commonly used in the field of laser cutting, and the center point compensation value is included according to the actual deviation.

[0071] If the workpiece has a large second image area, a lens with a wide field of view can be used. In the second image, except for the center point, there is dynamic offset in other areas, so dynamic compensation is required for the remaining pixels.

[0072] S106. Perform dynamic compensation of mechanical coordinates for areas other than the center point of the second image, so that the compensated mechanical coordinates meet the calibration requirements.

[0073] The compensation method here is to compensate for areas other than the center point of the second image. The compensation direction for the first quadrant of the mechanical coordinate system involved in the second image is negative X and negative Y, the compensation direction for the second quadrant of the mechanical coordinate system is negative X and positive Y, the compensation direction for the third quadrant of the mechanical coordinate system is positive X and negative Y, and the compensation direction for the fourth quadrant of the mechanical coordinate system is positive X and positive Y.

[0074] It should be noted that the compensation direction for the first quadrant of the machine coordinate system is negative X and negative Y, which can be understood as moving a preset distance along the negative X and negative Y directions of the first quadrant of the machine coordinate system to compensate for the deviation. The compensation direction for the second quadrant of the machine coordinate system is negative X and positive Y, which can be understood as moving a preset distance along the negative X and positive Y directions of the second quadrant of the machine coordinate system to compensate for the deviation.

[0075] The specific compensation value can be calculated as follows:

[0076]

[0077] Where a0 is the inner product constant, a n It is the amplitude of the frequency domain cosine component, b n is the amplitude of the sinusoidal component in the frequency domain, n is a general parameter, and x is the distance from the compensation point to the center point.

[0078] Of course, this invention can also radiate offset values ​​from the center point of the workpiece to the surrounding area, and perform gradual compensation according to the distance from the center point of the workpiece. Finally, the coordinate values ​​of each marked point of the workpiece placed on the actual machine tool 2 are obtained, realizing the visual measurement and calibration process based on laser cutting.

[0079] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0080] Based on the above-described laser-cut-based visual measurement calibration method, it can be seen that the operation involved by the operator is simple, more user-friendly, easier to implement, and more convenient, thus improving calibration efficiency. Furthermore, since the calibration plate is manually placed, it cannot be guaranteed to be centered in the field of view of camera 1. Errors caused by placement are calculated and compensated for through the calibration method, making the operation simple and easy to complete. The calibration logic is more stable and has lower coupling. The calibration plate is easy to manufacture, does not require particularly demanding reflective materials, and uses a mother-daughter plate, riveted together, which is more ergonomic during operation. There is no mutual interference between the two points during calibration. When calibrating the second point, the substrate 3 does not need to move; simply rotating the color block around the rivet is sufficient to complete the calibration process. This invention can summarize calibration information, making it convenient for processing and monitoring personnel to review, effectively improving the efficiency of calibration process monitoring. It improves the accuracy and precision of workpiece calibration, thereby achieving timely and scientific supervision, management, and control of the entire calibration process.

[0081] The following are embodiments of the calibration system for long-distance visual measurement provided in this disclosure. This system belongs to the same inventive concept as the laser-cut-based visual measurement calibration method in the above embodiments. For details not described in detail in the embodiments of the calibration system for long-distance visual measurement, please refer to the embodiments of the laser-cut-based visual measurement calibration method described above.

[0082] The system includes: a hardware definition module, a zero-point return control module, an image processing module, an image correction module, a deviation compensation module, and a dynamic compensation module;

[0083] The hardware definition module is used to adjust the physical hardware parameters of the lens and camera 1 on the laser cutting machine so that the image clarity of the lens and camera 1 meets the preset clarity threshold.

[0084] In this embodiment, the laser cutting machine can convert light and shadow into CMOS signals, store the signals in a buffer, compress them, and transmit the image to the industrial control computer module. The adjustment process involves adjusting the focus and aperture to clearly present the light and shadow of the real environment onto the acquisition device of camera 1.

[0085] The zero-point return control module is used to control the laser cutting machine head to return to zero.

[0086] The shooting and processing module is used to control the movement of the machine tool 2, align the preset points of the calibration board with the laser red light spot, and execute the shooting process, so that the camera 1 can shoot the surface of the machine tool 2 and execute the calibration process.

[0087] In this embodiment, the image processing module also receives transmitted images from camera 1, establishes a process buffer, persistently stores the images in a database, and calls corresponding image processing software function modules to obtain meaningful information from the images, converting it into processing data for machine tool 2 for machining operations. The software functions of the image processing module include gigabit network SDK image acquisition, an image preprocessing module, a distortion correction module, a machine tool 2 calibration module, and a recognition module.

[0088] The image correction module is used to obtain the coordinate state of machine tool 2 through the pre-made reference point of machine tool 2 and the preset point of calibration plate, rotate machine tool 2 by a preset angle, obtain the rotation angle to correct the image, and obtain the actual positive matching image of machine tool 2.

[0089] The deviation compensation module analyzes the coordinates of the center point of the image based on the actual forward matching of the machine tool 2. It then locates and finds the edges in a preset direction according to the coordinates of the center point of the image, and obtains the actual deviation between the coordinates of each edge after edge finding and the mechanical coordinates of the machine tool 2. The actual deviation is then included in the compensation value.

[0090] The dynamic compensation module is used to dynamically compensate the mechanical coordinates of areas other than the center point of the image, so that the compensated mechanical coordinates meet the calibration requirements.

[0091] The units and algorithm steps of the various examples described in the embodiments of the laser-cut-based visual measurement calibration method disclosed in this invention can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of each example have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0092] The flowchart of the laser-cut-based visual measurement calibration method illustrates the architecture, functionality, and operation of possible implementations of the apparatus, method, and computer program product according to various embodiments of the present disclosure. In this regard, each block in the flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing the specified logical function.

[0093] The laser-cut-based visual measurement and calibration system, comprising the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein, can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of each example have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can implement the described functions using different methods for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0094] Those skilled in the art will understand that various aspects of the laser-cut-based visual measurement calibration method can be implemented as a system, method, or program product. Therefore, various aspects of this disclosure can be specifically implemented in the following forms: a completely hardware implementation, a completely software implementation (including firmware, microcode, etc.), or a combination of hardware and software aspects, collectively referred to herein as a "circuit," "module," or "system."

[0095] In embodiments of the present invention, computer program code for performing the operations of the present disclosure may be written in one or more programming languages ​​or a combination thereof. The programming languages ​​include, but are not limited to, object-oriented programming languages ​​such as Java, Smalltalk, and C++, as well as conventional procedural programming languages ​​such as the "C" language or similar programming languages.

[0096] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A visual measurement calibration method based on laser cutting, characterized in that, The methods include, S101. Adjust the physical hardware parameters of the lens and camera on the laser cutting machine so that the image clarity of the lens and camera meets the preset clarity threshold. S102, Control the laser head of the laser cutting machine to return to zero; S103, a pre-made calibration plate, controls the laser head to move along the X and Y axes of the machine tool, aligns the preset points of the calibration plate with the laser red light spot, executes the shooting process, enables the camera to capture the machine tool surface and obtain the original first image, and executes the calibration process; The prefabricated calibration plate includes a base plate at the bottom and a color block on the top layer for calibration. One end of the base plate overlaps with one end of the color block and is fixed. Rotate the color block so that it forms a preset angle with the substrate; The calibration process is performed based on the calibration board, including the first calibration process and the second calibration process, so that the camera can capture the machine tool area and select the color block area on the calibration board in the image of the machine tool area to complete the calibration procedure. S104. The machine tool coordinate state is obtained through the pre-made machine tool reference point and the preset point of the calibration plate. The machine tool is rotated by a preset angle to obtain the rotation angle. The first image is corrected, and a second image of the actual positive matching of the machine tool is obtained. S105. Based on the coordinates of the center point of the second image in the actual forward matching of the machine tool, the edge is located and searched in a preset direction according to the coordinates of the center point of the second image, and the actual deviation between the coordinates of each edge after edge search and the mechanical coordinates of the machine tool is obtained. The actual deviation is included in the compensation value. S106. Perform dynamic compensation of mechanical coordinates for areas other than the center point of the second image so that the compensated mechanical coordinates meet the calibration requirements. The compensation value is calculated as follows: Where a0 is the inner product constant, a n It is the amplitude of the frequency domain cosine component, b n is the amplitude of the sinusoidal component in the frequency domain, n is a general parameter, and x is the distance from the compensation point to the center point.

2. The visual measurement calibration method based on laser cutting according to claim 1, characterized in that, In step S101, the lens is fixedly installed in the preset position of the camera, the lens aperture is adjusted, and the imaging brightness is adjusted to the preset brightness threshold.

3. The visual measurement calibration method based on laser cutting according to claim 2, characterized in that, Step S101 also includes: adjusting the focal length of the lens so that the sharpness of the objects in the image reaches a preset sharpness threshold.

4. The visual measurement calibration method based on laser cutting according to claim 1 or 2, characterized in that, In step S102, the zero-point return process is started; then the laser head is controlled to move along the X-axis, Y-axis and Z-axis of the machine tool to confirm the sensing signal of the machine tool during the movement. After the signal disappears, the coordinates are marked.

5. The visual measurement calibration method based on laser cutting according to claim 1 or 2, characterized in that, Step S104 further includes: the slope and rotation angle offset corresponding to the left edge of the color block in the calibration plate are calculated using the Pythagorean theorem and the arctangent trigonometric function, as follows: Where p1.x and p1.y are the image coordinates X and Y of the corner point of the first calibration plate, p2.x and p2.y are the image coordinates X and Y of the corner point of the second calibration plate, dK is the calculated slope, and dRad is the rotation angle offset value; The obtained rotation angle is used to correct the second image, and then the image is rotated in the opposite direction to obtain a second image that matches the actual forward orientation of the machine tool.

6. The visual measurement calibration method based on laser cutting according to claim 1 or 2, characterized in that, Step S106 further includes: compensating for other areas outside the center point of the second image. The compensation method is that the compensation direction for the first quadrant of the mechanical coordinate system involved in the second image is negative X and negative Y, the compensation direction for the second quadrant of the mechanical coordinate system is negative X and positive Y, the compensation direction for the third quadrant of the mechanical coordinate system is positive X and negative Y, and the compensation direction for the fourth quadrant of the mechanical coordinate system is positive X and positive Y.

7. A calibration system for long-distance visual measurement, characterized in that, The system employs the visual measurement and calibration method based on laser cutting as described in any one of claims 1 to 6; The system includes: a hardware definition module, a zero-point return control module, an image processing module, an image correction module, a deviation compensation module, and a dynamic compensation module; The hardware definition module is used to adjust the physical hardware parameters of the lens and camera on the laser cutting machine so that the image clarity of the lens and camera meets the preset clarity threshold. The zero-point return control module is used to control the laser cutting machine head to return to zero. The shooting and processing module is used to control the movement of the machine tool by using a pre-made calibration board, aligning the preset points of the calibration board with the laser red light spot, and executing the shooting process so that the camera can capture the machine tool surface and execute the calibration process. The image correction module is used to obtain the machine tool coordinate state through the pre-made machine tool reference point and the preset point of the calibration plate, rotate the machine tool by a preset angle, obtain the rotation angle to correct the image, and obtain the actual positive matching image of the machine tool. The deviation compensation module analyzes the coordinates of the center point of the image based on the actual forward matching of the machine tool. It then locates and finds the edges in a preset direction according to the coordinates of the center point of the image, obtains the actual deviation between the coordinates of each edge after edge finding and the mechanical coordinates of the machine tool, and includes the actual deviation in the compensation value. The dynamic compensation module is used to dynamically compensate the mechanical coordinates of areas other than the center point of the image, so that the compensated mechanical coordinates meet the calibration requirements.

8. A calibration terminal, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the steps of the visual measurement calibration method based on laser cutting as described in any one of claims 1 to 6.

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