Dual reference point correction method

Abstract

The invention relates to the technical field of automatic plug-in mounting equipment, in particular to a double-reference-point correction method, which comprises the following steps of: acquiring image information of a first reference point and a second reference point arranged on a lower camera module, and determining an actual coordinate when an upper camera is aligned with the first reference point based on the image information of the first reference point; comparing with a preset fixed coordinate value to generate a coordinate system translation correction parameter; calculating an included angle between a connecting line of two points and the X-axis direction based on the image information of the two datum points, and generating a coordinate system rotation correction parameter; according to the method, two correction parameters are integrated to update a plug-in machine coordinate system, a lead screw back clearance elimination operation is adopted to improve the basic positioning precision, a correction effect verification and historical data analysis mechanism is established, a double-reference-point design is adopted for the first time, the problems of coordinate system origin offset and X-axis orthogonality change are solved at the same time, and the precision of the plug-in machine is improved. And the long-term stable operation of the plug-in machine and the consistency among different machines are ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of automatic insertion equipment, in particular to a double-reference-point correction method for a plug-in machine, mainly applied to a visual coordinate calibration system in an automatic plug-in equipment for electronic components. BACKGROUND

[0002] A plug-in machine is a mechanical device used in the electronic manufacturing industry to automatically and accurately insert electronic components into the conductive through holes of a printed circuit board, mainly including a feeder device and a plug-in device. The feeder device is responsible for supplying electronic components, and the plug-in device grabs the components from the feeder device and inserts them onto the printed circuit board. The smoothness and accuracy of the interface between the feeder device and the plug-in machine have a significant impact on the overall work efficiency and quality of the plug-in machine.

[0003] In the prior art, the plug-in machine usually uses an upper and lower vision system to complete coordinate calibration. The upper camera is installed on an XY moving module, and the lower camera is fixed at the bottom of the device. However, the current industry's upper and lower vision correction algorithm has obvious deficiencies: on the one hand, most systems do not establish an effective correction mechanism, and when the hardware structure changes, it often leads to poor device precision; on the other hand, the lack of a unified reference point leads to a large difference in absolute coordinates between the same batch of devices, increasing the difficulty of program transplantation and use. In addition, it is particularly noteworthy that the existing technology generally lacks an effective method to solve the X-axis orthogonality change of the handling module, which seriously affects the precision stability of the device during long-term use.

[0004] Therefore, there is an urgent need in the industry for a method that can simultaneously solve the problems of coordinate system reference positioning and orthogonality correction to improve the precision and consistency of the plug-in machine. SUMMARY

[0005] In view of the deficiencies of the prior art, the purpose of the present application is to provide a double-reference-point correction method by setting two reference points on the lower camera module and using the upper camera to capture the two reference points, simultaneously solving the problems of coordinate system origin offset and X-axis orthogonality change, ensuring long-term stable operation of the plug-in machine and consistency between different machines.

[0006] The present application proposes a double-reference-point correction method, comprising:

[0007] Obtaining image information of a first reference point and a second reference point set on a lower camera module;

[0008] Based on the image information of the first reference point, determining the actual coordinates when the upper camera of the plug-in machine is aligned with the first reference point, and comparing with the preset fixed coordinate value to generate coordinate system translation correction parameters;

[0009] calculating an angle between a line connecting the first reference point and the second reference point and an X-axis direction based on the image information of the first reference point and the second reference point, and determining a coordinate system rotation correction parameter according to the angle; and

[0010] updating a plug-in machine coordinate system according to the coordinate system translation correction parameter and the coordinate system rotation correction parameter, so as to correct the relative relationship between the upper camera and the lower camera and the orthogonality of the upper camera translation along the X-axis.

[0011] As preferred, before the image information of the first reference point and the second reference point is acquired, the method further comprises:

[0012] during the control of the movement of the upper camera, a screw back lash elimination operation is performed, and the screw back lash elimination operation comprises:

[0013] before the movement direction of the upper camera is changed, the upper camera is first moved a predetermined distance towards the target direction; the actual position of the upper camera is adjusted according to a preset screw back lash parameter; and

[0014] the adjusted position parameter is recorded for subsequent coordinate calibration.

[0015] As preferred, the acquisition of the image information of the first reference point and the second reference point arranged on the lower camera module comprises:

[0016] the upper camera installed on the XY movement module is controlled to move to the approximate position of the first reference point;

[0017] the image of the first reference point is captured by the upper camera;

[0018] the position of the upper camera is adjusted according to the position offset of the first reference point in the image, so that the first reference point is located at the center position of the image;

[0019] the XY coordinate when the upper camera is aligned with the first reference point is recorded;

[0020] the upper camera is controlled to move to the approximate position of the second reference point;

[0021] the image of the second reference point is captured by the upper camera;

[0022] the position of the upper camera is adjusted according to the position offset of the second reference point in the image, so that the second reference point is located at the center position of the image; and

[0023] the XY coordinate when the upper camera is aligned with the second reference point is recorded.

[0024] As preferred, the image information based on the first fiducial point determines the actual coordinates of the camera on the insert machine when it is aligned with the first fiducial point, and compares it with the preset fixed coordinate value, to generate the coordinate system translation correction parameter, which includes:

[0025] The accurate position of the first fiducial point in the image is obtained through an image processing algorithm;

[0026] The actual XY coordinates of the upper camera when it is aligned with the first fiducial point are calculated through coordinate transformation;

[0027] The actual XY coordinates are compared with the preset fixed coordinate value (a, b);

[0028] The deviation between the actual XY coordinates and the fixed coordinate value (a, b) is calculated; and

[0029] The coordinate system translation correction parameter is generated according to the deviation.

[0030] As preferred, the image information based on the first fiducial point and the second fiducial point calculates the included angle between the line connecting the first fiducial point and the second fiducial point and the X-axis direction, and determines the coordinate system rotation correction parameter according to the included angle, which includes:

[0031] The coordinates (x1, y1) of the upper camera when it is aligned with the first fiducial point and the coordinates (x2, y2) of the upper camera when it is aligned with the second fiducial point are obtained;

[0032] The included angle θ formed by the line connecting the first fiducial point and the second fiducial point and the X-axis direction is calculated through trigonometric functions according to the coordinates (x1, y1) and the coordinates (x2, y2);

[0033] The angle deviation is calculated by comparing the included angle θ with the standard angle value; and

[0034] The coordinate system rotation correction parameter is generated according to the angle deviation.

[0035] As preferred, the coordinate system of the insert machine is updated according to the coordinate system translation correction parameter and the coordinate system rotation correction parameter, which includes:

[0036] The coordinate system translation correction parameter and the coordinate system rotation correction parameter are integrated into a complete coordinate transformation matrix;

[0037] The validity of the coordinate transformation matrix is verified;

[0038] The coordinate transformation matrix is applied to the insert machine control system; and

[0039] The coordinate system parameters of the insert machine are updated.

[0040] As preferred, after updating the coordinate system of the inserter, the method further comprises:

[0041] controlling the upper camera to move to a preset inspection position again;

[0042] capturing a verification image of the first fiducial point and the second fiducial point;

[0043] calculating a corrected position error;

[0044] judging whether the position error is within a preset allowable range; and

[0045] if the position error exceeds the preset allowable range, re-executing the double-fiducial point correction method.

[0046] As preferred, the method further comprises:

[0047] recording parameter changes in each correction process;

[0048] analyzing historical trends of the parameter changes;

[0049] evaluating long-term stability of the inserter according to the historical trends; and

[0050] generating a device maintenance prompt information when a coordinate deviation change trend exceeds a warning threshold.

[0051] As preferred, the preset fixed coordinate values (a, b) are the same for different inserters of the same model, to ensure consistency of coordinate systems of different inserters.

[0052] As preferred, the method is used in the following scenarios of the inserter:

[0053] daily calibration before production;

[0054] precision recovery after device maintenance;

[0055] emergency correction when detecting abnormal insertion precision; and

[0056] coordinate system initialization before a new model product is put into production.

[0057] The beneficial effects of the present application include:

[0058] 1. By double-fiducial point design, the correction mechanism for simultaneously solving coordinate system translation and rotation errors is realized for the first time in the industry, significantly improving the positioning precision of the inserter;

[0059] 2. The fixed coordinate value corresponding to the fiducial point is adopted, to ensure the consistency of coordinate systems between different inserters of the same model, greatly simplifying the difficulty of program transplantation and cross-inserter use;

[0060] 3. Through the back lash elimination technology of the lead screw, the basic precision problem in the mechanical system is solved, and a reliable foundation is provided for coordinate calibration;

[0061] 4. The reference point connecting line angle analysis is innovatively applied, the real-time monitoring and automatic compensation of the X-axis orthogonality change are realized, and the long-existing technical problem in the industry is solved;

[0062] 5. A complete calibration data record and analysis mechanism is established, through historical trend analysis, the early warning and preventive maintenance of the equipment state are realized, and the precision maintenance time of the equipment is prolonged. BRIEF DESCRIPTION OF DRAWINGS

[0063] Figure 1 It is a top view of the XY moving module of the application;

[0064] Figure 2 It is a schematic diagram of the lower camera and the double reference points;

[0065] Figure 3 It is a schematic diagram of the upper camera;

[0066] Figure 4 It is a system structure schematic diagram of the double reference point correction method of the application, which shows the spatial relationship of the upper camera, the lower camera, the double reference points and the XY moving module;

[0067] Figure 5 It is a coordinate system origin calibration process schematic diagram of the application, which shows the process of using reference point 1 to correct the translation of the coordinate system;

[0068] Figure 6 It is a coordinate system orthogonality calibration process schematic diagram of the application, which shows the process of calculating and correcting the included angle between the connecting line of reference point 1 and reference point 2 and the X-axis;

[0069] Figure 7 It is a lead screw back lash elimination operation process schematic diagram of the application, which shows the method of eliminating the back lash of the lead screw in the coordinate positioning process;

[0070] Figure 8 It is a comprehensive correction parameter generation and verification process schematic diagram of the application. DETAILED DESCRIPTION

[0071] Please refer to the accompanying Figures 1-5 The specific embodiments of the application will be described in detail below with reference to the accompanying drawings.

[0072] In a basic embodiment of the application, a double reference point correction method is provided and applied to an electronic component automatic insertion device. The method sets two reference points on the lower camera module, and uses the upper camera to shoot the two reference points, so as to realize the comprehensive calibration of the coordinate system, including translation correction and rotation correction.

[0073] Referring to Figures 1-8 , the double reference point correction method of the present application first acquires image information of a first reference point and a second reference point arranged on a lower camera module. The two reference points are fixed on the lower camera module, and an upper camera is mounted on an XY moving module and can move freely in a working plane. By controlling the upper camera to move to a proper position, images of the two reference points can be captured.

[0074] Based on the image information of the first reference point, the method determines the actual coordinates of the upper camera of the plug-in machine when it is aligned with the first reference point, and compares them with preset fixed coordinate values to generate coordinate system translation correction parameters. Preferably, the preset fixed coordinate values can be set to (100mm, 100mm), which is uniform for different machines of the same model, thereby ensuring the consistency of the coordinate system between different machines.

[0075] Next, based on the image information of the first reference point and the second reference point, the method calculates the included angle between the line connecting the first reference point and the second reference point and the X-axis direction, and determines the coordinate system rotation correction parameter according to the included angle. This step is one of the core innovations of the present application, which can effectively detect and correct the orthogonality change of the X-axis, which is the first solution in the industry.

[0076] Finally, the plug-in machine coordinate system is updated according to the coordinate system translation correction parameter and the coordinate system rotation correction parameter, and the correction of the relative relationship between the upper and lower cameras and the translation X-axis orthogonality of the upper camera is realized.

[0077] In a preferred embodiment of the present application, in order to improve the basic positioning accuracy, before acquiring the image information of the first reference point and the second reference point, the method further includes a screw back lash elimination operation.

[0078] Referring to Figure 7 , the screw back lash elimination operation includes: during the movement of the upper camera, especially before changing the moving direction of the upper camera, first moving the upper camera a predetermined distance towards the target direction. The predetermined distance is usually set to be between 0.5mm and 2mm, preferably 1mm, which is sufficient to eliminate the mechanical clearance in the screw system, but does not cause excessive additional movement time.

[0079] Then, the actual position of the upper camera is adjusted according to the preset screw back lash parameter. This screw back lash parameter is usually determined by professional measurement before the equipment is shipped, and for a typical plug-in machine system, the screw back lash parameters of X-axis and Y-axis are usually between 0.01mm and 0.05mm, depending on the quality and usage of the screw.

[0080] Finally, the compensated position parameters are recorded for subsequent coordinate calibration. This method can effectively eliminate the positioning error caused by the backlash of the lead screw, improve the basic positioning accuracy, and provide a reliable foundation for the entire correction system.

[0081] In another embodiment of the application, the detailed process of obtaining image information of the first reference point and the second reference point arranged on the lower camera module is as follows:

[0082] First, the upper camera mounted on the XY moving module is controlled to move to the approximate position of the first reference point. This approximate position can be the position recorded in the last calibration, or the position estimated according to the mechanical design.

[0083] Then, the image of the first reference point is taken by the upper camera. The resolution of the image is usually set to 1280x960 or higher to ensure sufficient positioning accuracy.

[0084] Next, according to the position offset of the first reference point in the image, the position of the upper camera is adjusted so that the first reference point is located at the center of the image. This step is usually performed iteratively, with the camera position adjusted each time according to the offset calculated by image processing until the offset is less than a predetermined threshold (usually 0.01mm).

[0085] After completion, the XY coordinates of the upper camera when aligning the first reference point are recorded. This coordinate will be compared with the preset fixed coordinate value to generate the translation correction parameter.

[0086] Similarly, the upper camera is controlled to move to the approximate position of the second reference point, the image is taken, the position is adjusted so that the second reference point is located at the center of the image, and the corresponding XY coordinates are recorded.

[0087] This precise positioning method, combined with high-resolution image processing, can ensure high-precision acquisition of reference point coordinates and provide reliable data foundation for subsequent coordinate calibration.

[0088] In a key embodiment of the application, based on the image information of the first reference point, the actual coordinates of the upper camera of the plug-in machine when aligning the first reference point are determined, and compared with the preset fixed coordinate value to generate the coordinate system translation correction parameter. The detailed process is as follows:

[0089] First, the precise position of the first reference point in the image is obtained by image processing algorithm. The image processing algorithm used here usually includes image preprocessing, feature extraction, and sub-pixel positioning steps, which can achieve sub-pixel level (usually better than 0.1 pixels) positioning accuracy.

[0090] Then, the actual XY coordinates of the upper camera when aligning to the first fiducial point are calculated through coordinate transformation. This coordinate transformation takes into account the intrinsic parameters of the camera (such as focal length, principal point position, etc.) and extrinsic parameters (such as camera pose), as well as the relationship between the camera and the mechanical coordinate system.

[0091] Next, the actual XY coordinates are compared with the preset fixed coordinate value (a, b). As mentioned earlier, this fixed coordinate value is uniform for different machines of the same model, for example, it can be set to (100mm, 100mm).

[0092] The deviation between the actual XY coordinates and the fixed coordinate value (a, b) is calculated. This deviation directly reflects the translation of the current machine coordinate system relative to the standard coordinate system.

[0093] Finally, the coordinate system translation correction parameter is generated according to the deviation. This correction parameter will be used for subsequent coordinate conversion to ensure that all operations are performed in a standardized coordinate system.

[0094] Through this method, the invention achieves the consistency of coordinate systems between different machines, greatly simplifying the porting and use of programs.

[0095] In another core embodiment of the invention, based on the image information of the first fiducial point and the second fiducial point, the angle between the line connecting the first fiducial point and the second fiducial point and the X-axis direction is calculated, and the detailed process of determining the coordinate system rotation correction parameter according to the angle is as follows:

[0096] First, the coordinates (x1, y1) of the upper camera when aligning to the first fiducial point and the coordinates (x2, y2) of the upper camera when aligning to the second fiducial point are obtained. These two coordinate points have been obtained through image processing and accurate positioning in the previous steps.

[0097] Then, according to the two coordinate points, the angle θ between the line connecting the first fiducial point and the second fiducial point and the X-axis direction is calculated through trigonometric functions. This calculation can be achieved through the following formula:

[0098]

[0099] Where: θ is the angle between the line connecting the first fiducial point and the second fiducial point and the X-axis direction, in radians; (x1, y1) is the coordinate of the first fiducial point; (x2, y2) is the coordinate of the second fiducial point; arctan is the inverse tangent function.

[0100] After obtaining the angle θ, it is compared with the standard angle value to calculate the angle deviation. The standard angle value is usually 0 degrees, indicating that the line connecting the first fiducial point and the second fiducial point should be parallel to the X-axis. If the actual measured angle is not 0, it indicates that there is an orthogonal change in the X-axis.

[0101] Finally, based on this angular deviation, generate coordinate system rotation correction parameters. This correction parameter will be used to correct the angular error in the coordinate system, ensuring the orthogonality of the X and Y axes.

[0102] Through this method, the invention can effectively detect and correct the change of X-axis orthogonality, solving the long-standing technical problem in the industry.

[0103] In an embodiment of the invention, the detailed process of updating the coordinate system of the plug-in machine according to the coordinate system translation correction parameters and the coordinate system rotation correction parameters is as follows:

[0104] First, integrate the coordinate system translation correction parameters and the coordinate system rotation correction parameters into a complete coordinate transformation matrix. This transformation matrix can be represented as:

[0105]

[0106] Where: θ is the rotation angle, determined by the coordinate system rotation correction parameters; Δx and Δy are the translation amounts, determined by the coordinate system translation correction parameters; T is the comprehensive transformation matrix, used to convert the original coordinates to the corrected coordinates.

[0107] Then, verify the effectiveness of this coordinate transformation matrix. This is usually done by applying the transformation matrix to a set of test points, and then checking whether the transformed coordinates meet the expectations.

[0108] Next, apply the verified coordinate transformation matrix to the plug-in machine control system. This means that all subsequent coordinate calculations and motion control will be based on this updated coordinate system.

[0109] Finally, update the coordinate system parameters of the plug-in machine and save these parameters to the system configuration for continued use at the next start-up.

[0110] Through this method, the invention realizes the comprehensive update of the coordinate system of the plug-in machine, while solving the problems of translation error and rotation error of the coordinate system, ensuring the installation precision and consistency.

[0111] In another embodiment of the invention, after updating the coordinate system of the plug-in machine, a correction effect verification process is included, which specifically includes:

[0112] First, control the upper camera to move to the preset verification position again. This preset verification position can be the first reference point, the second reference point, or other feature points with known coordinates.

[0113] Then, take verification images of the first reference point and the second reference point, and determine the positions of these reference points in the image through image processing algorithms.

[0114] Next, the corrected positional error, which is the difference between the actual position and the theoretical position, is calculated. This error can be represented by the Euclidean distance:

[0115]

[0116] where Error is the positional error in millimeters; (x actual ,y actual ) are the actual measured coordinates; and (x theory ,y theory ) are the theoretical coordinates calculated based on the corrected coordinate system.

[0117] The positional error is then judged against a pre-set allowable range. For high-precision insert machines, this allowable range is typically set to within 0.02 mm, which is a reasonable threshold determined considering camera resolution, mechanical precision, and actual application requirements.

[0118] If the positional error exceeds the pre-set allowable range, the dual-reference point correction method needs to be re-executed until the error meets the requirements.

[0119] Through this strict verification process, the invention ensures the reliability of the correction effect, providing a guarantee for the high-precision operation of the insert machine.

[0120] In an advanced embodiment of the invention, a historical data analysis and early warning mechanism is also included, specifically including:

[0121] First, record the parameter changes during each correction process, including translation correction parameters, rotation correction parameters, positional errors, and other key data. These data are stored in chronological order to form a historical database.

[0122] Then, analyze the historical trends of these parameter changes. This can be done through statistical analysis methods such as linear regression, moving average, etc., to detect the rules and trends of parameter changes. For example, if the translation correction parameter shows a consistent increasing trend in the last few calibrations, it may indicate that the mechanical system has a gradual drift or deformation.

[0123] Next, based on the historical trends, assess the long-term stability of the insert machine. This assessment can be quantitatively represented as a stability index, for example:

[0124]

[0125] where SI is the stability index, ranging from 0 to 1, with a higher value indicating greater stability; Var(P) is the variance of parameter P, reflecting the degree of parameter fluctuation; P max and P min are the maximum and minimum values of parameter P, respectively, determining the range of parameter values.

[0126] Finally, when the coordinate deviation trend is detected to exceed the warning threshold, a device maintenance prompt information is generated. This warning threshold can be set to a parameter change rate exceeding 10% / month, or a stability index below 0.8, etc., depending on the device accuracy requirements and actual application scenarios.

[0127] Through this historical data analysis and warning mechanism, the present application can discover potential accuracy problems in advance, realize preventive maintenance, and prolong the accuracy maintenance time and service life of the device.

[0128] In another embodiment of the present application, the preset fixed coordinate value (a, b) is the same for different plug-in machines of the same model, to ensure the consistency of the coordinate system of different machines.

[0129] This fixed coordinate value is usually determined during the device design phase and written into the product specifications. For example, for a plug-in machine of a certain model, the fixed coordinate value of the first reference point can be set to (100mm, 100mm). This means that for all plug-in machines of this model, when the camera is aligned to the first reference point, their coordinate systems will be calibrated to the same value.

[0130] This unified coordinate system brings significant convenience: first, the same program can be directly run on different machines without the need for coordinate system adjustment; second, production data between different machines can be directly compared and analyzed, facilitating quality control and production management; finally, when new equipment needs to be added or replaced, the equipment replacement can be quickly completed without affecting the production schedule.

[0131] Through this coordinate system consistency guarantee mechanism, the present application greatly improves the universality and flexibility of the plug-in machine system, providing convenience for production line optimization and management.

[0132] In the last embodiment of the present application, the double-reference-point correction method can be applied to various scenarios of plug-in machines, including:

[0133] Daily calibration before production: Before starting daily production, perform a double-reference-point correction to ensure that the device is in the best state. This usually takes 2-3 minutes, but can significantly improve the production efficiency and quality throughout the day.

[0134] Accuracy recovery after device maintenance: After the device is maintained, replaced or adjusted, perform a double-reference-point correction to quickly recover the device accuracy. This is very important for reducing the debugging time after maintenance and ensuring the maintenance quality.

[0135] Emergency correction when detecting insertion accuracy anomalies: When insertion accuracy anomalies are found during production, immediate double-reference-point correction can be performed to eliminate accuracy anomalies caused by coordinate system problems. This real-time response capability greatly improves the stability of production.

[0136] Coordinate system initialization before new model products are put into production: Before new model products are put into production, double-reference-point correction is performed to ensure that the coordinate system meets the requirements of the new products. This flexible adaptation capability enables the device to quickly switch between different product production.

[0137] Through application in these different scenarios, the double-reference-point correction method of the present application demonstrates its wide applicability and significant practical value, providing strong technical support for the accuracy improvement and production efficiency optimization of the plug-in machine.

[0138] In summary, the double-reference-point correction method of the present application, through the organic combination of innovative double-reference-point design, screw backlash elimination, and trigonometric function analysis, etc. technologies, constructs a complete plug-in machine coordinate system correction solution. This method can simultaneously solve the two core problems of coordinate origin offset and X-axis orthogonality change, achieving high-precision, high-stability, and high-consistency coordinate systems, and providing advanced technical support for the plug-in machine industry.

[0139] The above-described embodiments only express the specific implementation of the present application, and the description is more specific and detailed, but it should not be interpreted as limiting the scope of the present patent. It should be noted that for those skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the scope of protection of the present application.

Claims

1. A dual fiducial correction method, characterized by, The method comprises: acquiring image information of a first reference point and a second reference point arranged on a lower camera module; based on the image information of the first reference point, determining the actual coordinates of the upper camera of the plug-in machine when it is aligned with the first reference point, and comparing them with the preset fixed coordinate value to generate coordinate system translation correction parameters; based on the image information of the first reference point and the second reference point, calculating the angle between the line connecting the first reference point and the second reference point and the X-axis direction, and determining the coordinate system rotation correction parameters according to the angle; and updating the plug-in machine coordinate system according to the coordinate system translation correction parameters and the coordinate system rotation correction parameters, to correct the relative relationship between the upper and lower cameras and the orthogonality of the upper camera translation X-axis.

2. The dual reference point correction method of claim 1, wherein, Before acquiring the image information of the first reference point and the second reference point, the method further comprises: during the control of the movement of the upper camera, performing a screw backlash elimination operation, which comprises: before changing the moving direction of the upper camera, moving the upper camera a predetermined distance towards the target direction; adjusting the actual position of the upper camera according to the preset screw backlash parameters; and recording the compensated position parameters for subsequent coordinate calibration.

3. The dual reference point correction method of claim 1, wherein, The acquisition of the image information of the first reference point and the second reference point arranged on the lower camera module comprises: controlling the upper camera mounted on the XY movement module to move to the approximate position of the first reference point; capturing the image of the first reference point by the upper camera; adjusting the position of the upper camera according to the position offset of the first reference point in the image, so that the first reference point is located at the center position of the image; recording the XY coordinates when the upper camera is aligned with the first reference point; controlling the upper camera to move to the approximate position of the second reference point; capturing the image of the second reference point by the upper camera; adjusting the position of the upper camera according to the position offset of the second reference point in the image, so that the second reference point is located at the center position of the image; and recording the XY coordinates when the upper camera is aligned with the second reference point.

4. The dual reference point correction method of claim 1, wherein, The determination of the actual coordinates of the upper camera of the plug-in machine when it is aligned with the first reference point based on the image information of the first reference point, and the comparison with the preset fixed coordinate value to generate coordinate system translation correction parameters, comprises: acquiring the accurate position of the first reference point in the image through an image processing algorithm; calculating the actual XY coordinates of the upper camera when it is aligned with the first reference point through coordinate transformation; comparing the actual XY coordinates with the preset fixed coordinate value (a, b); calculating the deviation between the actual XY coordinates and the fixed coordinate value (a, b); and generating coordinate system translation correction parameters according to the deviation.

5. The dual reference point correction method of claim 1, wherein, The calculation of the angle between the line connecting the first reference point and the second reference point and the X-axis direction based on the image information of the first reference point and the second reference point, and the determination of the coordinate system rotation correction parameters according to the angle, comprises: acquiring the coordinates (x1, y1) of the upper camera when it is aligned with the first reference point and the coordinates (x2, y2) of the upper camera when it is aligned with the second reference point; According to the coordinates (x1, y1) and the coordinates (x2, y2), the included angle θ formed by the line connecting the first reference point and the second reference point and the X-axis direction is calculated by a trigonometric function; The included angle θ is compared with a standard angle value, and an angle deviation is calculated; and According to the angle deviation, a coordinate system rotation correction parameter is generated.

6. The dual reference point correction method of claim 1, wherein, The updating of the coordinate system of the plug-in machine according to the coordinate system translation correction parameter and the coordinate system rotation correction parameter includes: The coordinate system translation correction parameter and the coordinate system rotation correction parameter are integrated into a complete coordinate transformation matrix; The validity of the coordinate transformation matrix is verified; The coordinate transformation matrix is applied to the plug-in machine control system; and The coordinate system parameters of the plug-in machine are updated.

7. The dual reference point correction method of claim 1, wherein, After the coordinate system of the plug-in machine is updated, the method further includes: The upper camera is controlled to move to the preset verification position again; A verification image of the first reference point and the second reference point is captured; A corrected position error is calculated; It is judged whether the position error is within a preset allowable range; and If the position error exceeds the preset allowable range, the double-reference-point correction method is re-executed.

8. The dual reference point correction method of claim 1, wherein, The method further includes: The parameter changes in each correction process are recorded; The historical trend of the parameter changes is analyzed; According to the historical trend, the long-term stability of the plug-in machine is evaluated; and When it is detected that the coordinate deviation change trend exceeds a warning threshold, a device maintenance prompt information is generated.

9. The dual reference point correction method of claim 1, wherein, The preset fixed coordinate value (a, b) is the same for different plug-in machines of the same model, so as to ensure the consistency of the coordinate systems of different machines.

10. The dual reference point correction method of claim 1, wherein, The method is used in the following scenarios of the plug-in machine: Daily calibration before production; Accuracy recovery after device maintenance; Emergency correction when detecting abnormal plug-in accuracy; and Coordinate system initialization before production of a new model product.

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