Laser automatic calibration method and system

Abstract

The present application shows a laser automatic calibration method, the method comprising: determining pixel equivalent; obtaining the error of the pixel equivalent; determining a first distance according to a preset calibration error and the error of the pixel equivalent; determining the calibration point spacing according to the first distance, and determining the check point according to the calibration point spacing; determining the calibration point radius according to the calibration point spacing; after determining the calibration point spacing and the calibration point radius, determining the array mode of the calibration points; and performing laser automatic calibration according to the array mode of the calibration points. The technical solution shown in the present application can make the calibration process more concise without requiring the laser to mark the calibration point on the calibration plate in advance, and reduce the complex parameter settings during the calibration process, thus simplifying the calibration process.

Description

Technical Field

[0001] The present application relates to the field of industrial vision technology, and in particular to a laser automatic calibration method and system. Background Art

[0002] In the field of industrial vision, camera calibration has important applications in the processes of inspection, measurement, and assembly. Through camera calibration, the internal and external parameters of the camera can be calculated, and the relationship between the camera coordinate system and the world coordinate system can be established, so as to measure and inspect the size, defects, position, etc. of the product and realize automated production.

[0003] The existing calibration method is to place a calibration sheet in the camera field of view and fix it, mark the calibration sheet with a laser to obtain multiple calibration points, and record the coordinate value of the center of each calibration point in the laser field of view. A CCD camera is used to obtain the coordinate value of the calibration point in the camera field of view, determine the correspondence between the coordinate value in the camera field of view and the coordinate value in the laser field of view, and guide the laser to perform high-precision work through the camera.

[0004] However, when the existing laser marks on the calibration sheet to obtain the calibration points, the radius of the calibration points and the interval between the calibration points are determined based on the user's experience, and sometimes the calibration accuracy cannot be met. When the camera is installed in different ways, the images collected by the camera are also different, but the coordinates of the calibration points in the camera's field of view need to correspond one-to-one with the coordinates of the calibration points in the laser's field of view. To this end, the user needs to determine the horizontal and vertical axis directions of the laser. If the determination fails, the entire calibration process will also fail. When calculating the calibration error on site, some calibration points with known coordinates are generally marked on a new calibration plate (not the calibration plate marked by the laser), and then the calibration results are converted into theoretical coordinates. The errors are calculated by comparing the theoretical values ​​and actual values ​​of these calibration points, which is costly. The existing calibration process is complicated and the steps are cumbersome, which brings difficulties to users. Summary of the invention

[0005] The present application provides a laser automatic calibration method and system, which can make the calibration process more concise without the need to mark the laser on a calibration plate in advance to obtain calibration points, and reduce complex parameter settings during the calibration process, thereby simplifying the calibration process.

[0006] In the first aspect, the present application shows a laser automatic calibration method, which includes: determining a pixel equivalent; obtaining an error of the pixel equivalent; determining a first distance based on a preset calibration error and the error of the pixel equivalent; determining a calibration point spacing based on the first distance to determine a check point based on the calibration point spacing; determining a calibration point radius based on the calibration point spacing; after determining the calibration point spacing and the calibration point radius, determining an array mode of the calibration points; and performing laser automatic calibration based on the array mode of the calibration points.

[0007] In some embodiments, determining the pixel equivalent includes: marking a calibration plate with a laser to obtain a circle of a first radius; obtaining a second radius of the circle of the first radius in an image in a camera; and determining that the value of the pixel equivalent is twice the second radius.

[0008] In some embodiments, determining the first distance according to a preset calibration error and an error in the pixel equivalent includes: determining the first distance as a quotient of the preset calibration error and the pixel equivalent.

[0009] In some embodiments, determining the calibration point spacing according to the first distance includes: The product of times and the pixel equivalent is determined as the calibration point spacing.

[0010] In some embodiments, determining the calibration point radius according to the calibration point spacing includes: setting the calibration point radius to be smaller than one quarter of the calibration point spacing; preferably, setting the calibration point radius to one fifth of the calibration point spacing.

[0011] In some embodiments, the array method for determining the calibration points includes: establishing a coordinate system with the center of the circle of the first radius as the center of the coordinate axis of the calibration plate, and marking the positions (0, 0), (0, D), and (D, 0) of the coordinate system by a laser to obtain calibration points; determining the angle a between the camera field of view and the laser field of view according to the position of the calibration point in the camera field of view; wherein the actual length of the camera field of view is M, and the actual width is N; determining the number of calibration points in the horizontal direction of the calibration plate by the laser according to the angle between the camera field of view and the laser field of view; marking in the horizontal direction of the calibration plate to obtain calibration points; determining the number of calibration points in the vertical direction of the calibration plate by the laser according to the angle between the camera field of view and the laser field of view; marking in the vertical direction of the calibration plate to obtain calibration points.

[0012] In some embodiments, the automatic laser calibration according to the array method of the calibration points includes: obtaining the center coordinates of all calibration points in the camera field of view; converting the center coordinates of all calibration points in the camera field of view and the coordinates of the calibration points in the laser field of view by the least squares method.

[0013] In some embodiments, determining the number of horizontal calibration points of the laser on the calibration plate according to the angle between the camera field of view and the laser field of view includes: determining a second distance from the center of the calibration plate coordinate axis to the top boundary of the camera field of view; the second distance is the quotient of M / 2 and sin a; determining the number m of calibration points in the horizontal direction according to the second distance, and the number m of calibration points in the horizontal direction is obtained by first obtaining the difference between the second distance and the radius of the calibration point, and then calculating the quotient of the difference and the spacing between the calibration points.

[0014] In some embodiments, determining the number of vertical calibration points of the laser on the calibration plate based on the angle between the camera field of view and the laser field of view includes: judging whether the number of vertical calibration points on the calibration plate is greater than 1; if so, the number of vertical calibration points n is obtained by first calculating the difference between half the width of the calibration plate in the laser field of view and the radius of the calibration point, and then calculating the quotient of the difference and the spacing between the calibration points.

[0015] In the second aspect, the present application also shows a laser automatic calibration system, which includes: a metering module, the first metering module is used to determine the pixel equivalent; obtain the error of the pixel equivalent; determine the first distance according to the preset calibration error and the error of the pixel equivalent; a marking module, the marking module is used to determine the calibration point spacing according to the first distance, so as to determine the verification point according to the calibration point spacing; determine the calibration point radius according to the calibration point spacing; after determining the calibration point spacing and the calibration point radius, determine the array mode of the calibration points; a calibration module, the calibration module is used to perform laser automatic calibration according to the array mode of the calibration points.

[0016] The technical solution shown above can make the laser without marking the calibration point on the calibration board in advance, making the calibration process more concise, reducing complex parameter settings during the calibration process, and simplifying the calibration process. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0018] Figure 1A schematic diagram showing the working principle of a galvanometer laser according to some embodiments is shown;

[0019] Figure 2 A schematic diagram of a calibration point array method on a conventional calibration chip according to some embodiments is shown;

[0020] Figure 3 A schematic diagram showing the relationship between a camera coordinate system and a laser coordinate system according to some embodiments;

[0021] Figure 4 A flow chart of a laser automatic calibration method according to some embodiments is shown;

[0022] Figure 5 A schematic diagram of an arrangement of checkpoints in a calibration plate is shown;

[0023] Figure 6 A schematic diagram showing an arrangement of calibration points in a calibration plate is shown;

[0024] Figure 7 A schematic diagram of an arrangement of calibration points on a calibration plate within a camera field of view is shown. DETAILED DESCRIPTION

[0025] In order to make the purpose, implementation mode and advantages of the present application clearer, the exemplary implementation mode of the present application will be clearly and completely described below in conjunction with the drawings in the exemplary embodiments of the present application. Obviously, the described exemplary embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0026] Based on the exemplary embodiments described in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the claims attached to this application. In addition, although the disclosure in this application is introduced according to one or several exemplary examples, it should be understood that each aspect of these disclosures can also constitute a complete implementation method separately. It should be noted that the brief description of the terms in this application is only for the convenience of understanding the implementation methods described below, and is not intended to limit the implementation methods of this application. Unless otherwise specified, these terms should be understood according to their common and usual meanings.

[0027] It should be understood that the terms "first", "second", "third", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances, for example, they can be implemented according to an order other than those given in the diagrams or descriptions of the embodiments of this application.

[0028] The professional terms involved in the embodiments of the present application are explained below.

[0029] The embodiments of the present application are applicable to industrial vision systems, which are image recognition machines used for automatic inspection, workpiece processing and assembly automation, and control and monitoring of production processes.

[0030] Camera calibration is a prerequisite for industrial vision systems to perform inspection, measurement, and assembly. Camera calibration is the process of converting from the world coordinate system to the camera coordinate system, and then from the camera coordinate system to the image coordinate system, so as to measure and inspect the size, defects, and position of the product to achieve automated production.

[0031] Lasers can be used in cutting, welding, marking and other subdivided industrial fields. By establishing a conversion relationship between the camera and the laser, the laser can be guided by the camera to perform high-precision work.

[0032] Figure 1 The working principle of a galvanometer laser is shown in FIG. Figure 1 As shown, the galvanometer laser includes: a laser beam generator, a first galvanometer connected to a motor moving in the horizontal axis direction, a second galvanometer connected to a motor moving in the vertical axis direction, and a flat field lens. In a specific application process, the position of the laser beam emitted by the laser beam generator remains unchanged, and the motor moving in the horizontal axis direction and the motor moving in the vertical axis direction are adjusted to move the laser beam within the working range to perform operations such as cutting, welding, and marking.

[0033] The existing camera calibration method is to fix a calibration piece in the camera field of view and mark the calibration piece with a laser to obtain multiple calibration points. For example, Figure 2 Six rows and six columns of calibration points are shown. The laser can record the coordinate value of the center of each calibration point in the laser field of view. The charge coupled device (CCD) camera can acquire an image of a circular target on a device cross section and find the coordinate value of the center of the calibration point in the camera field of view. The conversion relationship between the camera coordinate system and the laser coordinate system is calculated based on the coordinate value of the center of the calibration point in the camera field of view and the coordinate value of the center of the calibration point in the laser field of view. There may be a rotation, scaling, and translation relationship between the camera coordinate system and the laser coordinate system. Figure 3 A schematic diagram showing the relationship between a camera coordinate system and a laser coordinate system is shown.

[0034] However, when the existing laser is marking on the calibration sheet, the radius of the calibration point and the interval between the calibration points are determined based on the user's experience, and sometimes the calibration accuracy cannot be met. When the camera is installed in different ways, the image collected by the camera is also different, but the coordinates of the calibration points in the camera's field of view need to correspond one-to-one with the coordinates of the calibration points in the laser's field of view. To this end, the user needs to determine the horizontal and vertical axis directions of the laser. If the determination fails, the entire calibration process will also fail. When calculating the calibration error on site, some calibration points with known coordinates are generally marked on a new calibration plate (not the calibration plate marked by the laser), and then the calibration results are converted into theoretical coordinates. The errors are calculated by comparing the theoretical values ​​and actual values ​​of these calibration points, which is costly. The existing calibration process is complicated and the steps are cumbersome, which brings difficulties to users.

[0035] In order to solve the above problems, the present application shows a laser automatic calibration method, which can make the calibration process more concise without the need to mark the laser on the calibration plate in advance to obtain the calibration points, and reduce the complex parameter settings during the calibration process, thereby simplifying the calibration process.

[0036] Figure 4 A flow chart of a laser automatic calibration method is shown in FIG. Figure 4 As shown, the method includes:

[0037] Step S101, determining pixel equivalent;

[0038] In some embodiments, determining the pixel equivalent includes:

[0039] A circle with a first radius is obtained by marking a calibration plate with a laser; a second radius of the circle with the first radius in an image in a camera is obtained; and a value of the pixel equivalent is determined to be twice the second radius.

[0040] In some embodiments, the first radius can be set to 0.5 mm. In a specific implementation, the pixel equivalent is the actual physical size represented by a pixel in the image. When a 0.5 mm circle is obtained by marking on the calibration plate with a laser, the circle finding tool of the CCD camera can obtain the second radius r of the 0.5 mm circle in the camera's field of view. The pixel equivalent is twice the second radius 2r.

[0041] Step S102, obtaining the error of the pixel equivalent;

[0042] It should be noted that there is an error e mm / pixel between the pixel equivalent calculated according to the second radius r corresponding to the 0.5 mm circle in the camera field of view and the actual distance from the calibration plate to the camera.

[0043] Step S103, determining a first distance according to a preset calibration error and an error of the pixel equivalent;

[0044] In some embodiments, determining the first distance according to a preset calibration error and the pixel equivalent error includes:

[0045] The first distance is determined as a quotient of the preset calibration error and the pixel equivalent.

[0046] In the specific implementation, a preset calibration error E mm / pixel is required, and the error of the pixel equivalent needs to be smaller than the preset calibration error. Then, during the calibration, the maximum distance between the maximum error point and the calibration point, i.e., the first distance

[0047] Step S104, determining a calibration point spacing according to the first distance, so as to determine a check point according to the calibration point spacing;

[0048] The determining the calibration point spacing according to the first distance includes:

[0049] The first distance The product of times and the pixel equivalent is determined as the calibration point spacing.

[0050] Figure 5 A schematic diagram of the arrangement of calibration points in a calibration plate is shown. Figure 5 As shown in , since the checkpoints and calibration points need to be set on the same calibration board, and the checkpoints cannot cover the calibration points, the checkpoints are set in the gap between the calibration points, that is, Figure 5 The distance between the calibration point and the center of the calibration point is the first distance, so the calibration point spacing D0 in the camera field of view is set to the first distance. times; The actual calibration point spacing on the calibration plate

[0051] Step S105, determining the calibration point radius according to the calibration point spacing;

[0052] In some embodiments, determining the calibration point radius R according to the calibration point spacing includes:

[0053] Setting the radius of the calibration points to be smaller than one quarter of the spacing between the calibration points;

[0054] Preferably, the radius of the calibration points is set to one fifth of the spacing between the calibration points.

[0055] In the specific implementation, since the checkpoints cannot cover the calibration points and the checkpoints need to be set in the gaps between the calibration points, the calibration points are usually Figure 5The arrangement shown, therefore, the radius of the calibration point is set to be less than one-fourth of the calibration point spacing to meet the marking requirements, that is, R<D / 4; the technical solution shown in the embodiment of the present application sets the radius of the calibration point to one-fifth of the calibration point spacing, that is, R=D / 5.

[0056] Step S106, after determining the calibration point spacing and the calibration point radius, determining the array mode of the calibration points;

[0057] In some embodiments, Figure 6 A schematic diagram of the arrangement of calibration points in a calibration plate is shown. Figure 6 As shown, the array method for determining the calibration points includes:

[0058] A coordinate system is established with the center of the circle of the first radius as the center of the coordinate axis of the calibration plate, and the positions (0, 0), (0, D), and (D, 0) of the coordinate system are marked by a laser to obtain calibration points; wherein the calibration points at the position (0, 0) of the laser coordinate system can cover the circle of the first radius to obtain the following: Figure 6 The arrangement of calibration points is shown.

[0059] Figure 7 A schematic diagram of the arrangement of calibration points on the calibration plate within the camera field of view is shown. Figure 7 As shown, according to the position of the calibration point in the camera field of view, the angle a between the camera field of view and the laser field of view is determined; wherein the actual length of the camera field of view is M, and the actual width is N; wherein the units of M and N are both pixel.

[0060] Determine the number of calibration points of the laser in the horizontal direction on the calibration plate according to the angle between the camera field of view and the laser field of view; and mark the calibration points in the horizontal direction of the calibration plate;

[0061] It should be noted that the actual camera field length M and actual width N are obtained by multiplying the known camera parameters and pixel equivalent. Figure 7 For ease of description, the center point of the calibration plate in the camera field of view is determined as point O, the intersection of the horizontal axis of the calibration plate and the wide side of the calibration plate facing the camera field of view is determined as point A, the intersection of the horizontal axis of the calibration plate and the top edge of the camera field of view is determined as point B, the intersection of one corner of the calibration plate and the top edge in the camera field of view is determined as point C, and the angle between the horizontal axis of the calibration plate and the top edge of the camera field of view is determined as angle a between the camera field of view and the laser field of view.

[0062] It should be noted that this application Figure 7 The rectangle of the calibration plate shown in the figure is variable in the camera field of view, and its rotation angle can be adjusted according to actual conditions. This application is only an exemplary embodiment.

[0063] In some embodiments, determining the number of horizontal calibration points of the laser on the calibration plate according to the angle between the camera field of view and the laser field of view includes:

[0064] Determine a second distance from the center of the calibration plate coordinate axis to the top boundary of the camera field of view; the second distance is the quotient of M / 2 and sin a;

[0065] In a specific implementation, the second distance from the center of the calibration plate coordinate axis to the top edge of the camera field of view is OB, then

[0066]

[0067] The number m of calibration points in the horizontal direction is determined according to the second distance. The number m of calibration points in the horizontal direction is obtained by first obtaining the difference between the second distance and the radius of the calibration points, and then calculating the quotient of the difference and the calibration point spacing.

[0068] In the specific implementation,

[0069] The number of calibration points of the laser in the vertical direction on the calibration plate is determined according to the angle between the camera field of view and the laser field of view; and the calibration points are obtained by marking in the vertical direction of the calibration plate.

[0070] In some embodiments, determining the number of calibration points of the laser in the vertical direction on the calibration plate according to the angle between the camera field of view and the laser field of view includes:

[0071] Determine whether the number of calibration points in the vertical direction on the calibration plate is greater than 1;

[0072] If so, the number n of calibration points in the vertical direction is obtained by first calculating the difference between half the width of the calibration plate in the laser field of view and the radius of the calibration points, and then calculating the quotient of the difference and the spacing between the calibration points.

[0073] In the specific implementation, Figure 7 As shown, AC is first calculated based on AB, where AC = AB × tan a; if AC < D + R; then vertical marking is performed on the calibration plate to obtain a number of calibration points less than 1, and such marking cannot be performed. At this time, m = m-1, and the values ​​of AB and AC are recalculated, and multiple iterations are performed until AC > D + R; at this time, the number of vertical calibration points Among them, [] indicates taking an integer.

[0074] Therefore, the number of calibration points in the camera field of view is (2m+1)×(2n+1). The coordinates of the center of the initial calibration point are (-mD, -nD), and the coordinates of the remaining calibration points are similar.

[0075] Step S107, performing automatic laser calibration according to the array mode of the calibration points.

[0076] The automatic laser calibration according to the array mode of the calibration points includes:

[0077] Get the center coordinates of all calibration points in the camera's field of view;

[0078] The coordinates of the center of all the calibration points in the camera field of view and the coordinates of the calibration points in the laser field of view are converted by the least square method.

[0079] It should be noted that the calibration points in the present application include but are not limited to circular ones, and may also be rectangular calibration points or cross-shaped calibration points. The scheme shown in the present application does not focus on the automatic extraction process of calibration points. Calibration points of other shapes can also achieve corresponding functions according to the technical scheme shown in the present application.

[0080] The present application also shows a laser automatic calibration system, the system comprising:

[0081] A metering module, wherein the first metering module is used to determine a pixel equivalent; obtain an error of the pixel equivalent; and determine a first distance according to a preset calibration error and the error of the pixel equivalent;

[0082] A marking module, the marking module is used to determine the calibration point spacing according to the first distance, to determine the check point according to the calibration point spacing; to determine the calibration point radius according to the calibration point spacing; and after determining the calibration point spacing and the calibration point radius, to determine the array mode of the calibration points;

[0083] A calibration module is used to perform automatic laser calibration according to the array mode of the calibration points.

[0084] An embodiment of the present application also provides a chip connected to a memory or including a memory, and used to read and execute a software program stored in the memory, and a method provided by an embodiment of the present application.

[0085] The present application embodiment also provides a computer program product, which includes one or more computer program instructions. When the computer loads and executes the computer program instructions, the process or function according to the above-mentioned various embodiments of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network or other programmable device. When it runs on a computer, the computer executes the method provided by the embodiment of the present application.

[0086] In this embodiment, a computer-readable storage medium is also provided, and the computer-readable storage medium can store computer program instructions. When the program instructions are executed, all steps of the image processing method of the above embodiments of the present application can be implemented. The computer-readable storage medium includes a disk, an optical disk, a read-only storage memory ROM or a random access memory RAM, etc.

[0087] In the above embodiments, all or part of the embodiments may be implemented by software, hardware, firmware or any combination thereof. When implemented by software, all or part of the embodiments may be implemented in the form of a computer program product, which is not limited in this embodiment.

[0088] It is also known to those skilled in the art that the various illustrative logical blocks and steps listed in this application can be implemented by electronic hardware, computer software, or a combination of the two. Whether such functions are implemented by hardware or software depends on the specific application and the design requirements of the entire system. Those skilled in the art can use various methods to implement the functions for each specific application, but such implementation should not be understood as exceeding the scope of protection of this application.

[0089] The various illustrative logic units and circuits described in this application can be implemented or operated by a general-purpose processor, a digital signal processor, an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination of the above. The general-purpose processor can be a microprocessor, and optionally, the general-purpose processor can also be any conventional processor, controller, microcontroller or state machine. The processor can also be implemented by a combination of computing devices, such as a digital signal processor and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a digital signal processor core, or any other similar configuration.

[0090] The steps of the method or algorithm described in this application can be directly embedded in hardware, a software unit executed by a processor, or a combination of the two. The software unit can be stored in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a removable disk, a CD-ROM, or any other storage medium in the art. Exemplarily, the storage medium can be connected to the processor so that the processor can read information from the storage medium and can write information to the storage medium. Optionally, the storage medium can also be integrated into the processor. The processor and the storage medium can be arranged in an ASIC, and the ASIC can be arranged in a UE. Optionally, the processor and the storage medium can also be arranged in different components in the UE.

[0091] Those skilled in the art can clearly understand that the technology in the embodiments of the present application can be implemented by means of software plus a necessary general hardware platform. Based on this understanding, the technical solution in the embodiments of the present application is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which can be stored in a storage medium such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods of each embodiment of the present application or some parts of the embodiments.

[0092] In this specification, the same or similar parts between the various embodiments can be referred to each other. In particular, for the network device / node or apparatus, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the description in the method embodiment.

[0093] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

[0094] For the convenience of explanation, the above description has been made in conjunction with specific embodiments. However, the above exemplary discussion is not intended to be exhaustive or limit the embodiments to the specific forms disclosed above. Based on the above teachings, various modifications and variations can be obtained. The selection and description of the above embodiments are to better explain the principles and practical applications, so that those skilled in the art can better use the embodiments and various different variations of the embodiments suitable for specific use considerations.

Claims

1. A laser automatic calibration method, characterized in that: The method comprises: Determine pixel equivalents; Obtaining an error of the pixel equivalent; Determining a first distance according to a preset calibration error and an error of the pixel equivalent; determining a calibration point spacing according to the first distance, so as to determine a check point according to the calibration point spacing; Determining the calibration point radius according to the calibration point spacing includes: setting the calibration point radius to be smaller than one quarter of the calibration point spacing; After determining the calibration point spacing and the calibration point radius, determining the array mode of the calibration points, including: establishing a coordinate system with the center of the circle of the first radius as the center of the coordinate axis of the calibration plate, and marking the positions (0, 0), (0, D), and (D, 0) of the coordinate system by a laser to obtain calibration points; determining the angle a between the camera field of view and the laser field of view according to the position of the calibration point in the camera field of view; wherein the actual length of the camera field of view is M, and the actual width is N; determining the number of calibration points in the horizontal direction of the calibration plate by the laser according to the angle between the camera field of view and the laser field of view; marking in the horizontal direction of the calibration plate to obtain calibration points; determining the number of calibration points in the vertical direction of the calibration plate by the laser according to the angle between the camera field of view and the laser field of view; marking in the vertical direction of the calibration plate to obtain calibration points; Laser automatic calibration is performed according to the array mode of the calibration points.

2. The laser automatic calibration method according to claim 1, characterized in that: The determining of the pixel equivalent comprises: Marking the calibration plate by laser to obtain a circle with a first radius; Obtain a second radius of the circle of the first radius in the camera image; The pixel equivalent is determined to be twice the second radius.

3. The laser automatic calibration method according to claim 1, characterized in that: The determining the first distance according to the preset calibration error and the pixel equivalent error comprises: The first distance is determined as a quotient of the preset calibration error and the error of the pixel equivalent.

4. The laser automatic calibration method according to claim 3, characterized in that: The determining the calibration point spacing according to the first distance includes: The first distance The product of times and the pixel equivalent is determined as the calibration point spacing.

5. The laser automatic calibration method according to claim 1, characterized in that: The step of determining the calibration point radius according to the calibration point spacing includes: The radius of the calibration points is set to one fifth of the spacing between the calibration points.

6. The laser automatic calibration method according to claim 5, characterized in that: The automatic laser calibration according to the array mode of the calibration points includes: Get the center coordinates of all calibration points in the camera's field of view; The coordinates of the center of all the calibration points in the camera field of view and the coordinates of the calibration points in the laser field of view are converted by the least square method.

7. The laser automatic calibration method according to claim 5, characterized in that: The step of determining the number of horizontal calibration points of the laser on the calibration plate according to the angle between the camera field of view and the laser field of view includes: Determine a second distance from the center of the calibration plate coordinate axis to the top boundary of the camera field of view; the second distance is the quotient of M / 2 and sin a; The number m of calibration points in the horizontal direction is determined according to the second distance. The number m of calibration points in the horizontal direction is obtained by first obtaining the difference between the second distance and the radius of the calibration points, and then calculating the quotient of the difference and the calibration point spacing.

8. The laser automatic calibration method according to claim 7, characterized in that: The step of determining the number of calibration points of the laser in the vertical direction on the calibration plate according to the angle between the camera field of view and the laser field of view includes: Determine whether the number of calibration points in the vertical direction on the calibration plate is greater than 1; If so, the number n of calibration points in the vertical direction is obtained by first calculating the difference between half the width of the calibration plate in the laser field of view and the radius of the calibration points, and then calculating the quotient of the difference and the spacing between the calibration points.

9. A laser automatic calibration system, characterized in that: The system comprises: A metering module, the metering module is used to determine a pixel equivalent; obtain an error of the pixel equivalent; and determine a first distance according to a preset calibration error and the error of the pixel equivalent; A marking module, the marking module is used to determine the calibration point spacing according to the first distance, so as to determine the calibration point according to the calibration point spacing; determine the calibration point radius according to the calibration point spacing, including: setting the calibration point radius to be less than one-fourth of the calibration point spacing; after determining the calibration point spacing and the calibration point radius, determine the array mode of the calibration point, including: establishing a coordinate system with the center of the circle of the first radius as the center of the coordinate axis of the calibration plate, and marking the (0, 0), (0, D), and (D, 0) positions of the coordinate system by a laser to obtain the calibration points ; According to the position of the calibration point in the camera field of view, determine the angle a between the camera field of view and the laser field of view; wherein the actual length of the camera field of view is M, and the actual width is N; according to the angle between the camera field of view and the laser field of view, determine the number of calibration points of the laser in the horizontal direction on the calibration plate; mark the calibration point in the horizontal direction of the calibration plate; determine the number of calibration points of the laser in the vertical direction on the calibration plate according to the angle between the camera field of view and the laser field of view; mark the calibration point in the vertical direction of the calibration plate; A calibration module is used to perform automatic laser calibration according to the array mode of the calibration points.

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