Welding seam tracking and real-time compensation system of automobile welding fixture

Abstract

The invention discloses a welding seam tracking and real-time compensation system of an automobile welding clamp, and relates to the technical field of data processing. Real-time data of the surface of an automobile workpiece is obtained, a welding path is obtained, the welding path is stored in a welding robot, an actual welding path is obtained and transmitted to the welding robot through a laser vision sensor, and the welding robot is connected with the welding robot. Comparing whether the welding path and the actual path have deviation or not, if the deviation exists, adjusting and moving the postures of the welding fixture and the welding gun according to the actual path, and performing deviation compensation. Real-time data of the surface of the automobile workpiece and real-time data before welding and during welding are obtained through image acquisition and processing; according to the method, the identification precision and confidence output are improved by combining the segmentation number and repeated iteration, the deviation value is calculated based on the welding path and the actual path, real-time compensation is carried out, the welding accuracy of the automobile welding fixture is improved, and artificial interference and material waste are reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of data processing, and particularly relates to a welding seam tracking and real-time compensation system of an automobile welding fixture. BACKGROUND

[0002] Welding is a necessary process method in modern mechanical manufacturing industry, and is widely used in vehicle manufacturing. Unlike the current traditional spot welding process, brazing can achieve molecular bonding between two steel plates. In common terms, the hardness of the welded steel plate is equivalent to a whole steel plate, thereby improving the body strength by 30%, and greatly improving the bonding accuracy of the vehicle body. Generally speaking, the bumps from the ground when the vehicle is running on the road will be converted into thousands of times of torsional motion per minute to test the vehicle body. If the bonding accuracy and strength of the vehicle body are not enough, the vehicle may produce abnormal noise and have a large noise, and in severe cases, the damage of the parts installed on the vehicle, such as the transmission and the front and rear axles, or the rupture of the vehicle body may occur. Therefore, brazing has great significance compared with traditional spot welding.

[0003] At present, the Chinese invention patent with the application number CN107020452 discloses a welding robot, which mainly comprises a base, a rotating motor, a rotating shaft, a large arm rod, a small arm rod, a welding head and the like. One end of the large arm rod is matched with the base, and the other end of the large arm rod is used for being matched with the small arm rod and the welding head of the welding robot. The large arm rod drives the small arm rod and the welding head to make multi-dimensional movement in space, so as to implement welding on the joint of the whole plate. The end of the welding head is provided with a welding wire. The high-temperature welding arc generated by the welding head melts the welding wire, and then implements welding on the whole plate. Although the precision of automobile welding is improved, the temperature is too high during welding, which may cause the welding seam to deviate. The welding seam is not tracked, and real-time compensation is not implemented when the welding seam deviates. This is not conducive to the improvement of the accuracy of welding, and there is no remedy when the deviation occurs, which has limitations. SUMMARY

[0004] The technical problem solved by the present application is that in the related art, the welding robot makes multi-dimensional movement in space to implement welding on the joint of the whole plate, so as to improve the precision of automobile welding. However, real-time tracking of the welding seam is not implemented, and compensation measures are not implemented when the welding position deviates. This is not conducive to the improvement of the accuracy of welding, and there is still a situation that the welding path deviates due to high temperature changes. The problem has not been fundamentally solved, and there are limitations.

[0005] To solve the above technical problems, the present application provides the following technical scheme: a welding seam tracking and real-time compensation system of an automobile welding fixture, comprising a collection module, an analysis module and a compensation module: The collection module is used for obtaining real-time data of a welded automobile workpiece. The analysis module is used for obtaining a welding path, storing the welding path into a welding robot, obtaining an actual path of welding, and transmitting the actual path of welding to the welding robot through a laser vision sensor; The compensation module is used for comparing the welding path and the actual path to determine whether there is deviation, and adjusting and moving a welding fixture and a welding gun pose according to the actual path to compensate for the deviation if there is deviation.

[0006] As a preferred scheme of the automobile welding fixture seam tracking and real-time compensation system, the acquisition module comprises an acquisition unit. The acquisition unit is used for real-time scanning a surface of the automobile workpiece according to a laser vision sensor bound on the automobile welding fixture, leaving a stripe on the surface of the workpiece through a linear laser to form a deformation, and acquiring the deformation by the laser vision sensor.

[0007] As a preferred scheme of the automobile welding fixture seam tracking and real-time compensation system, the image acquisition and preprocessing module further comprises a calculation unit. The real-time data comprises shape data, welding fixture state data, welding gun pose data, position data and feature data of the automobile workpiece seam; The calculation unit is used for capturing the stripe in the deformation by a high-frame-rate camera to obtain pixel coordinates, converting the pixel coordinates into three-dimensional point cloud data by laser triangulation, and acquiring the shape data, the welding fixture state data, the position data and the feature data of the automobile workpiece seam according to the three-dimensional point cloud data. The position data comprises seam position deviation, seam center point coordinates, seam normal vector and seam tangent vector. The feature data comprises depth data, angle data, gap data and thermal deformation rate data of a groove; The shape data comprises curved surface curvature change data and thermal deformation displacement data. The welding fixture state data comprises welding fixture shape data and positioning reference data. The welding gun pose data comprises approach angle data and working angle data.

[0008] As a preferred scheme of the automobile welding fixture seam tracking and real-time compensation system, the analysis module comprises a welding path unit. The welding path unit is used for obtaining a workpiece number according to automobile workpiece data and feature data, obtaining a welding path in a welding gun console system according to the workpiece number, and the automobile workpiece comprising an automobile workpiece shape and an automobile workpiece material.

[0009] As a preferred scheme of the welding seam tracking and real-time compensation system of the automobile welding fixture, the welding path unit comprises key point coordinates. The welding path unit is used for setting first time information according to the key point coordinates and position data, segmenting the welding path into a plurality of welding path segments according to the first time information, numbering the welding path segments, and obtaining first numbering information, wherein the first time information comprises a start time point, a welding seam center time point and an end time point. According to the first numbering information, the welding gun posture is adjusted by controlling the welding gun through the welding robot, and posture data is obtained. According to the surface curvature change data, the thermal deformation displacement data and the posture data, the welding path segment trend is obtained by using the laser vision sensor of the welding fixture. The welding path unit is repeated until the welding seam is completed, different welding path segment trends in the first numbering information are obtained, the different welding path segment trends are iteratively merged according to the first time information to obtain a welding path, and the welding path is stored in the welding robot.

[0010] As a preferred scheme of the welding seam tracking and real-time compensation system of the automobile welding fixture, the analysis module further comprises an actual path unit. The actual path unit is used for inputting the posture data into the welding gun control system of the welding robot before formal welding of the automobile welding fixture. The precise position data, feature data and shape data of the automobile workpiece welding seam are obtained by real-time scanning of the automobile workpiece surface through the laser vision sensor. According to the position data, second time information is set, and the actual welding path is obtained in real time according to the second time information, the feature data and the shape data, and is transmitted to the welding robot through the laser vision sensor, wherein the second time information comprises a start time point, a welding seam center time point and an end time point.

[0011] As a preferred scheme of the welding seam tracking and real-time compensation system of the automobile welding fixture, the compensation module comprises a deviation compensation unit. The deviation compensation unit is used for extracting the welding path stored in advance when the welding robot obtains the actual path, segmenting and numbering the welding path according to the second time information to obtain a second welding path. According to the second time information, the actual path and the second welding path are compared one by one to obtain position deviation three-dimensional data. If the position deviation three-dimensional data is zero, there is no deviation, and the actual path is correct. If the position deviation three-dimensional data is not zero, there is deviation, and adjustment is made according to the position deviation three-dimensional data; If the position deviation three-dimensional data is greater than zero, the automobile workpiece is pulled inwards by the welding fixture for merging, the welding gun posture is adjusted according to the position deviation three-dimensional data, and deviation compensation is performed; If the position deviation three-dimensional data is less than zero, the automobile workpiece is pulled outwards by the welding fixture for separating, the welding gun posture is adjusted according to the position deviation three-dimensional data, and deviation compensation is performed; The actual path of the next step is welded according to the welding path.

[0012] As a preferred scheme of the weld tracking and real-time compensation system of the automobile welding fixture, wherein the three-dimensional point cloud data: According to the linear laser generator in the laser vision sensor, laser is emitted to leave a stripe on the surface of the automobile workpiece, so that the surface of the automobile workpiece is deformed, the high-frame-rate camera in the laser vision sensor captures the stripe in the deformation, the reflected light of the stripe enters the camera for photoelectric conversion to obtain a pixel voltage signal, the voltage signal is analog-digital converted to obtain a pixel coordinate, and the laser triangulation is used to extract the second three-dimensional point cloud from the pixel coordinate.

[0013] As a preferred scheme of the weld tracking and real-time compensation system of the automobile welding fixture, wherein the actual path of welding is obtained: Before formal welding of the automobile welding fixture, the posture data is input into a welding gun control system in the welding robot, when formal welding of the automobile welding fixture starts, the welding fixture scans the surface of the automobile workpiece in real time through the laser vision sensor, the image acquisition and preprocessing module is repeated, real-time weld tracking is performed, the position data, feature data and shape data of the automobile workpiece weld at each moment before welding are obtained, the actual path unit is repeated according to the position data, feature data and shape data, and the actual path of welding is obtained in real time.

[0014] As a preferred scheme of the weld tracking and real-time compensation system of the automobile welding fixture, wherein the actual path of the next step is welded according to the welding path: After the welding robot receives the actual path from the laser vision sensor, deviation calculation is performed by comparing the actual path with the welding path, position deviation three-dimensional data is obtained, the welding fixture and the welding gun posture are immediately adjusted by the welding robot according to the position deviation three-dimensional data, so that the actual path of the next step is welded according to the welding path, and the whole weld process is repeated according to the image calculation unit, the path analysis unit and the deviation compensation unit from the formal start until the weld is completed.

[0015] The beneficial effects of the present application are: through the laser vision sensor of the acquisition module, the shape data before welding and during welding, the welding fixture state data, the welding gun posture data, the position data and feature data of the automobile workpiece weld are accurately obtained, which helps to accurately calculate the position deviation three-dimensional data and lays a foundation for subsequent compensation. The analysis module obtains the subsequent trend of the weld through the laser vision sensor on the welding fixture, compares it with the welding path trend, obtains the position deviation three-dimensional data, can accurately control the weld trend, greatly reduces the manual intervention, improves the welding accuracy, reduces the waste of resources, and at the same time, the compensation module adjusts the welding gun and the welding fixture according to the obtained position deviation three-dimensional data, compensates the error from the welding source, improves the welding accuracy, greatly speeds up the production rhythm, significantly optimizes the production efficiency, and greatly reduces the comprehensive cost. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 The basic flowchart of the automobile welding fixture weld tracking and real-time compensation system provided by an embodiment of the present application is shown. DETAILED DESCRIPTION

[0017] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present application, not all embodiments.

[0018] Embodiments, with reference to Figure 1 , an automobile welding fixture weld tracking and real-time compensation system is provided, comprising: an acquisition module, an analysis module and a compensation module: The acquisition module is used to obtain real-time data of the welded automobile workpiece; The analysis module is used to obtain the welding path, store the welding path into the welding robot, obtain the actual path of welding, and transmit the actual path to the welding robot through the laser vision sensor; The compensation module is used to compare whether there is deviation between the welding path and the actual path, and if there is deviation, adjust and move the welding fixture and the welding gun posture according to the actual path, and compensate for the deviation.

[0019] In this embodiment, the laser vision sensor of the acquisition module accurately obtains shape data before and during welding, welding fixture state data, welding gun posture data, position data and feature data of the automobile workpiece weld, which helps to accurately calculate the position deviation three-dimensional data and lays the foundation for subsequent compensation. The analysis module obtains the subsequent trend of the weld through the laser vision sensor on the welding fixture, compares it with the welding path trend, obtains the position deviation three-dimensional data, accurately controls the weld trend, greatly reduces manual intervention, improves the accuracy of welding, reduces resource waste, and the compensation module adjusts the welding gun and welding fixture according to the obtained position deviation three-dimensional data to compensate for errors from the source, improve the accuracy of welding, greatly speed up the production rhythm, significantly optimize the production efficiency, and greatly reduce the comprehensive cost.

[0020] The acquisition unit is used to scan the surface of the automobile workpiece in real time according to the laser vision sensor bound on the automobile welding fixture, leave a stripe on the workpiece surface through a laser, form a deformation, and the laser vision sensor obtains the deformation; The real-time data includes shape data, welding fixture state data, welding gun posture data, position data and feature data of the automobile workpiece weld; The calculation unit is used to capture the stripe in the deformation by a high-frame-rate camera, obtain pixel coordinates, convert the pixel coordinates into three-dimensional point cloud data by laser triangulation, and obtain shape data, welding fixture state data, position data and feature data of the automobile workpiece weld according to the three-dimensional point cloud data; The position data includes weld position deviation, weld center point coordinates, weld normal vector and weld tangent vector; The feature data includes depth data, angle data, gap data and thermal deformation rate data of the groove; The shape data includes curved surface curvature change data and thermal deformation displacement data; The welding fixture state data includes welding fixture shape data and positioning reference data; The welding gun posture data includes approach angle data and working angle data.

[0021] In specific implementation, the laser vision sensor bound on the automobile welding fixture is used to scan the surface of the automobile workpiece in real time, and real-time data before and during welding is obtained in real time. The weld is tracked in real time, the welding direction is monitored, the foundation is laid for subsequent real-time compensation, the human resources are greatly reduced, the calculation accuracy is improved, and the waste of resources is avoided.

[0022] The welding path unit is used to obtain the workpiece number according to the automobile workpiece data and feature data, obtain the welding path in the corresponding welding gun console system according to the workpiece number, and the automobile workpiece includes automobile workpiece shape and automobile workpiece material.

[0023] The welding path unit is used to set first time information according to the key point coordinates and position data, divide the welding path into multiple welding path segments according to the first time information, number the welding path segments, and obtain first numbering information, wherein the first time information includes a start time point, a weld center time point, and an end time point; According to the welding robot control welding torch, the welding torch pose adjustment is performed according to the first numbering information, and pose data is obtained; According to the surface curvature change data, the thermal deformation displacement data, and the pose data, the welding path segment trend is obtained by using a welding fixture laser vision sensor; The welding path unit is repeated until the weld is completed, different welding path segment trends in the first numbering information are obtained, the different welding path segment trends are iteratively merged according to the first time information to obtain a welding path, and the welding path is stored in the welding robot.

[0024] The actual path unit is used to input the pose data into a welding torch control system in the welding robot before formal welding of the automobile welding fixture; The surface of the automobile workpiece is scanned in real time by the laser vision sensor to obtain accurate position data, feature data, and shape data of the automobile workpiece weld; According to the position data, second time information is set, and the actual welding path is obtained in real time according to the second time information, the feature data, and the shape data, and is transmitted to the welding robot by the laser vision sensor, wherein the second time information includes a start time point, a weld center time point, and an end time point.

[0025] In a specific implementation, the welding path is segmented according to the first time information, the welding path segments are numbered, and first numbering information is obtained, wherein the first time information includes a start time point, a weld center time point, and an end time point, the entire welding process is covered according to the first time information, the data obtained is more real and accurate, and the entire welding process is complete, the welding path is segmented and numbered according to the first time information, which makes the entire welding process orderly, facilitates the extraction of the welding path segment trend, provides convenience for subsequent comparison, greatly reduces resource waste and human intervention, makes the cumbersome steps simple, and provides data support for managers. According to the position data, the second time information is set, and the actual welding path is obtained in real time according to the second time information, the feature data, and the shape data. When the welding officially starts, the laser vision sensor obtains real-time data, sets the second time information according to the position data, and divides the weld trend into multiple segments. When welding the weld, the laser vision sensor obtains the second time information, the feature data, and the shape data of the current segment, thereby judging and obtaining the actual welding path of the next step. In this way, the segmented second time information, the feature data, and the shape data are obtained, and the actual welding path is judged. This method uses simple iteration to obtain the actual path, saves a lot of time and calculation cost, reasonably allocates resources, improves the efficiency of weld tracking, and has strong emergency response capability.

[0026] The deviation compensation unit is used for the welding robot to extract the welding path stored in advance when obtaining the actual path, divide and number the welding path according to the second time information, and obtain the second welding path. According to the second time information, the actual path and the second welding path are compared one by one to obtain position deviation three-dimensional data. If the position deviation three-dimensional data is zero, there is no deviation, and the actual path is correct. If the position deviation three-dimensional data is not zero, there is deviation, and adjustment is made according to the position deviation three-dimensional data. If the position deviation three-dimensional data is greater than zero, the automobile workpiece is merged inward by using the welding fixture, the welding gun posture is adjusted according to the position deviation three-dimensional data, and deviation compensation is performed. If the position deviation three-dimensional data is less than zero, the automobile workpiece is separated outward by using the welding fixture, the welding gun posture is adjusted according to the position deviation three-dimensional data, and deviation compensation is performed. The next actual path is welded according to the welding path.

[0027] In the embodiment, the welding path is segmented and numbered according to the second time information to obtain a second welding path, the first time information in the welding path unit is replaced by the second time information, the welding path unit is repeated to obtain a new welding path segment direction, the actual path is compared with the second welding path one by one according to the second time information to obtain position deviation three-dimensional data, and the segments of the actual path and the second welding path are compared according to the second time information, so that whether the position deviation three-dimensional data exists is more intuitively obtained, and only each segment needs to be calculated, so that the calculation amount is greatly reduced, the calculation efficiency is improved, accurate data are provided for subsequent implementation compensation, and the cost of manpower and materials is reduced.

[0028] According to the linear laser generator in the laser vision sensor, laser is emitted to leave a stripe on the surface of the automobile workpiece, the surface of the automobile workpiece is deformed, the high-frame-rate camera in the laser vision sensor captures the stripe in the deformation, the reflected light of the stripe enters the camera, photoelectric conversion is performed, a pixel voltage signal is acquired, the voltage signal is analog-digital converted, a pixel coordinate is obtained, and the pixel coordinate is extracted through laser triangulation to obtain three-dimensional point cloud data.

[0029] Before formal welding of the automobile welding fixture, the posture data is input into a welding gun control system in the welding robot, when the automobile welding fixture starts formal welding, the welding fixture scans the surface of the automobile workpiece in real time through the laser vision sensor, the image acquisition and preprocessing module is repeated, real-time weld tracking is performed, position data, feature data and shape data of the automobile workpiece weld before each moment in the welding process are acquired, the actual path unit is repeated according to the position data, the feature data and the shape data, and the actual path of welding is obtained in real time.

[0030] After the welding robot receives the actual path transmitted by the laser vision sensor, the actual path is compared with the welding path, deviation calculation is performed, position deviation three-dimensional data is obtained, according to the position deviation three-dimensional data, the welding robot immediately adjusts the posture of the welding fixture and the welding gun, so that the actual path in the following is welded according to the welding path, and the whole welding process is repeated according to the image calculation unit, the path analysis unit and the deviation compensation unit from the formal start until the welding is finished.

[0031] In the embodiment, the image acquisition preprocessing module is repeated, and real-time data of the current weld is obtained through the laser vision sensor without interruption, thereby laying a foundation for obtaining the actual path, making the data based on reality, not virtual, and improving the authenticity and operability of the welding path. According to the one-word laser generator in the laser vision sensor, laser is emitted, and a stripe is left on the surface of the automobile workpiece. The one-word laser adopts a high-frame-rate camera arranged symmetrically left and right, and through the laser diode, collimating lens and cylindrical mirror in the one-word laser generator, the point laser is diffused into a uniform straight line to obtain the stripe. According to the position deviation three-dimensional data, the welding robot will immediately adjust the welding fixture and welding gun posture, so that the actual path for the next welding is in accordance with the welding path. The position deviation three-dimensional data is divided into positive value, negative value and zero value, and according to different position deviation three-dimensional data, the welding robot is controlled to operate correspondingly, so that the welding quality is greatly improved, the welding defect rate is greatly reduced, and the production efficiency is significantly improved.

[0032] The laser vision sensor of the acquisition module accurately obtains the shape data before and during welding, the welding fixture state data, the welding gun posture data, the position data and the feature data of the automobile workpiece weld, which helps to accurately calculate the position deviation three-dimensional data and lays a foundation for subsequent compensation. The analysis module obtains the subsequent trend of the weld through the laser vision sensor on the welding fixture, compares it with the welding path trend, obtains the position deviation three-dimensional data, accurately controls the weld trend, greatly reduces manual intervention, improves the accuracy of welding, reduces resource waste, and the compensation module adjusts the welding gun and the welding fixture according to the obtained position deviation three-dimensional data to compensate for errors from the welding source, improve the accuracy of welding, greatly speed up the production rhythm, significantly optimize the production efficiency, and greatly reduce the comprehensive cost.

[0033] Those skilled in the art will appreciate that embodiments of the present application can be readily used as a method, a system or a computer program product. Accordingly, the present application can take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application can take the form of a computer program product on one or more computer-usable storage media (or computer- readable storage media) having computer-usable program code embodied in the medium. The medium can be any available storage media that can be accessed by a computer. By way of example, and not limitation, such computer-usable storage media can include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other storage medium(s) that can be used to carry or store desired computer program code in the form of instructions or data structures and that can be accessed by a computer. Also, the present application can be embodied in a computer program product that can be traded as goods or merchandise, through a computer-based platform or via a network. Figure 1 one or more functions specified in the flow or flows and / or blocks Figure 1 one or more functions specified in the flow or flows and / or blocks

[0034] It should be noted that the above-mentioned embodiments are only used to illustrate but not to limit the technical solutions of the present application. Although the present application is described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced equivalently without departing from the spirit and scope of the technical solutions of the present application, and they should be covered in the scope of the claims of the present application.

Claims

1. The weld seam tracking and real-time compensation system for automobile welding fixtures is characterized by: include: Acquisition module, analysis module and compensation module: The acquisition module is used to obtain real-time data of welding automobile workpieces; The analysis module is used to obtain the welding path, store the welding path in the welding robot, obtain the actual welding path, and transmit it to the welding robot through the laser vision sensor; The compensation module is used to compare whether there is a deviation between the welding path and the actual path. If there is a deviation, the welding fixture and welding gun posture are adjusted and moved according to the actual path to compensate for the deviation.

2. The weld seam tracking and real-time compensation system for automobile welding fixtures according to claim 1, characterized in that: The acquisition module includes an acquisition unit: The acquisition unit is used to scan the surface of the automobile workpiece in real time according to the laser vision sensor bound to the automobile welding fixture, leaving stripes on the workpiece surface by a straight laser to form deformation, and the laser vision sensor acquires the deformation.

3. The weld seam tracking and real-time compensation system for an automobile welding fixture as claimed in claim 2, characterized in that: The acquisition module also includes a calculation unit: The real-time data includes shape data, welding fixture status data, welding gun posture data, position data and feature data of automobile workpiece welds; The computing unit is used to capture the deformed fringes with a high frame rate camera, obtain pixel coordinates, convert the pixel coordinates into three-dimensional point cloud data by laser triangulation, and obtain shape data, welding fixture status data, and position data and feature data of the automobile workpiece weld based on the three-dimensional point cloud data; The position data includes weld position deviation, weld center point coordinates, weld normal vector and weld tangent vector; The characteristic data includes groove depth data, angle data, gap data and thermal deformation rate data; The shape data includes surface curvature change data and thermal deformation displacement data; The welding fixture state data includes welding fixture shape data and positioning reference data; The welding gun posture data includes approach angle data and working angle data.

4. The weld seam tracking and real-time compensation system for an automobile welding fixture as claimed in claim 3, characterized in that: The analysis module includes a welding path unit: The welding path unit is used to obtain a workpiece number according to automobile workpiece data and feature data, and obtain a welding path in a corresponding welding gun console system according to the workpiece number. The automobile workpiece includes an automobile workpiece shape and automobile workpiece material.

5. The weld seam tracking and real-time compensation system for automobile welding fixtures according to claim 4, characterized in that: The welding path unit includes key point coordinates: The welding path unit is used to set first time information according to the key point coordinates and position data, divide the welding path into multiple welding path segments according to the first time information, and number the welding path segments to obtain first numbering information, wherein the first time information includes a start time point, a weld center time point, and an end time point; Controlling the welding gun through the welding robot, adjusting the welding gun posture according to the first number information, and obtaining posture data; According to the surface curvature change data, thermal deformation displacement data and posture data, the laser vision sensor of the welding fixture is used to obtain the segmented direction of the welding path; Repeat the welding path unit until the weld is completed, obtain the different welding path segment directions in the first numbering information, iteratively merge the different welding path segment directions according to the first time information to obtain a welding path, and store the welding path in the welding robot.

6. The weld seam tracking and real-time compensation system for an automobile welding fixture as claimed in claim 5, characterized in that: The analysis module also includes an actual path unit: The actual path unit is used to input the posture data into the welding gun control system of the welding robot before the automobile welding fixture is officially welded; Scan the surface of the automotive workpiece in real time through the laser vision sensor to obtain the precise position data, feature data and shape data of the automotive workpiece weld; According to the position data, the second time information is set, and the actual welding path is obtained in real time according to the second time information, feature data and shape data, and transmitted to the welding robot through the laser vision sensor, wherein the second time information includes the start time point, the weld center time point and the end time point.

7. The weld seam tracking and real-time compensation system for an automobile welding fixture as claimed in claim 1, characterized in that: The compensation module includes a deviation compensation unit: The deviation compensation unit is used for the welding robot to extract the welding path stored in advance when obtaining the actual path, divide and number the welding path according to the second time information, and obtain the second welding path; According to the second time information, the actual path is compared with the second welding path in a one-to-one correspondence to obtain three-dimensional position deviation data; If the position deviation three-dimensional data is zero, then there is no deviation and the actual path is correct; If the position deviation three-dimensional data is not zero, there is a deviation, and adjustment is performed according to the position deviation three-dimensional data; If the three-dimensional position deviation data is greater than zero, the automobile workpiece is dragged inward by a welding fixture to be merged, and the welding gun posture is adjusted according to the three-dimensional position deviation data to perform deviation compensation; If the three-dimensional position deviation data is less than zero, the automobile workpiece is dragged outward by a welding fixture to separate the workpiece, and the welding gun posture is adjusted according to the three-dimensional position deviation data to perform deviation compensation; The actual path of the next step is welded according to the welding path.

8. The weld seam tracking and real-time compensation system for an automobile welding fixture as claimed in claim 3, characterized in that: The three-dimensional point cloud data: According to the one-way laser generator in the laser vision sensor, laser is emitted to leave stripes on the surface of the automobile workpiece, causing the surface of the automobile workpiece to deform. The high-frame rate camera in the laser vision sensor captures the stripes in the deformation, and the light reflected by the stripes enters the camera for photoelectric conversion to obtain pixel voltage signals. The voltage signals are converted from analog to digital to obtain pixel coordinates, and the pixel coordinates are extracted by laser triangulation to obtain three-dimensional point cloud data.

9. The weld seam tracking and real-time compensation system for an automobile welding fixture as claimed in claim 8, characterized in that: The actual path to obtain welding: Before the automobile welding fixture officially welds, the posture data is input into the welding gun control system in the welding robot. When the automobile welding fixture officially starts welding, the welding fixture uses the laser vision sensor to scan the surface of the automobile workpiece in real time, repeats the image acquisition preprocessing module, and performs real-time weld tracking to obtain the position data, feature data and shape data of the automobile workpiece weld before each moment in the welding process. Based on the position data, feature data and shape data, the actual path unit is repeated to obtain the actual path of the welding gun.

10. The weld seam tracking and real-time compensation system for automobile welding fixtures according to claim 7, characterized in that: The actual path of the next step is welded according to the welding path: After the welding robot receives the actual path from the laser vision sensor, it compares it with the welding path, calculates the deviation, and obtains three-dimensional data of the position deviation. Based on the three-dimensional data of the position deviation, the welding robot will immediately adjust the welding fixture and welding gun posture so that the actual path is then welded according to the welding path. The entire welding process is repeated according to the image calculation unit, path analysis unit and deviation compensation unit from the official start until the welding is completed.

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