A welding reverse deformation adaptive control method, a medium plate automatic grouping and welding method and system based on visual technology

Abstract

The application discloses a welding reverse deformation adaptive control method, a medium plate automatic grouping and welding method and system based on visual technology, and relates to the technical field of welding deformation control. The control method comprises the following steps: inputting material physical performance, process parameters and welding piece geometric size information into a main control system; calculating a welding piece temperature field, a stress field and a deformation field, learning and analyzing data to obtain the influence of the data on the welding piece deformation, and simulating and predicting the welding deformation; driving a servo motor by a control unit to drive a pressure head body to move, contacting a vertical plate and applying pressure according to a preset pressure, completing positioning through servo motor torque feedback, and generating a pre-deformation opposite to the predicted welding deformation; when welding, the vertical plate generates a positive deformation due to thermal stress, and the pre-deformation pressure and the thermal stress are offset; comparing the simulation prediction result of the welding deformation with the actual measurement result, and adjusting parameters according to the comparison result. The application realizes intelligent manufacturing of a turntable series product in a whole process, reduces or cancels personnel participation, and eliminates the interaction between personnel and equipment automatic operation.

Description

Technical Field

[0001] This invention relates to welding technology, specifically to a welding anti-deformation adaptive control method, a vision-based automatic assembly and welding method and system for medium and thick plates. Background Technology

[0002] Currently, robots are mainly used in welding processes, while the assembly and fixing of workpieces are mostly done manually. Manual assembly and fixing can cause large deviations in the dimensional form of workpieces, especially in the gaps between workpieces and at the joints. This limits the application of welding robots in automated welding and affects the final welding quality of the product, making it difficult to meet the needs of welding large batches of high-quality workpieces. Summary of the Invention

[0003] Purpose of the invention: The purpose of this invention is to provide a welding anti-deformation adaptive control method, a vision-based automatic assembly and welding method and system for medium and thick plates, to realize intelligent manufacturing of turntable series products throughout the entire process, minimize or eliminate human intervention, and eliminate interaction between personnel and equipment during automatic operation.

[0004] Technical solution: The present invention provides an adaptive control method for welding anti-deformation, comprising:

[0005] Input the material physical properties, process parameters, and weldment geometry information into the main control system;

[0006] The temperature field, stress field, and deformation field of the entire weldment are obtained by using the finite element analysis method. The temperature field, stress field, and deformation field data are then learned and analyzed to obtain the influence of the temperature field, stress field, and deformation field data on the deformation of the weldment. The welding deformation during the welding process is then simulated and predicted using the finite element analysis method.

[0007] The process database sends instructions to the bending plate pressure head slide assembly. The control unit drives the servo motor to move the pressure head body in the bending plate pressure head slide assembly according to the instructions. After the pressure head body contacts the plate, it applies pressure according to the preset pressure. Positioning is completed through the torque feedback of the servo motor, so that the plate produces a pre-deformation opposite to the predicted welding deformation.

[0008] During welding, thermal stress causes positive deformation of the vertical plate, and the pre-deformation pressure applied by the pressure head body cancels out the thermal stress that causes positive deformation.

[0009] The simulation prediction results of welding deformation are compared with the actual measurement results. If there is a deviation, the parameters, assumptions or calculation methods in the welding process are corrected and optimized.

[0010] We continuously analyze new welding production data, uncover patterns, optimize anti-deformation control strategies, and update the database.

[0011] Based on the same inventive concept, the present invention provides an automatic assembly and welding method for medium-thick plates based on vision technology, comprising:

[0012] The AGV material handling system automatically transfers materials from the parts buffer area to the workstation;

[0013] The truss robot sequentially picks up the base plate seat ring assembly, the upright plate assembly, and the small parts assembly from the workstation and places them onto the positioner tooling platform. The upright plate splicing welding positioner or the base plate splicing welding positioner automatically positions and clamps the base plate seat ring assembly, the upright plate assembly, and the small parts assembly on the positioner tooling platform.

[0014] The transport robot picks up the sub-component that is not in contact with the inner side of the upright plate from the workstation and places it on the secondary positioning table. The secondary positioning table positions the sub-component. The transport robot picks up the sub-component from the secondary positioning table and places it on the tooling. The positioner tooling platform automatically positions and clamps the sub-component that is not in contact with the inner side of the upright plate.

[0015] The above-mentioned welding anti-deformation adaptive control method applies pre-deformation pressure to the workpiece through the pressure head body. The pre-deformation pressure is used to offset the thermal stress during welding.

[0016] The welding robot assembles and spot welds the base plate seat ring assembly, upright plate assembly, small parts assembly, and sub-parts that do not fit against the inner side of the upright plate on the positioner tooling platform in a predetermined sequence, and welds the weld seams that need to be covered on the inner side of the upright plate.

[0017] The truss robot grabs the sub-component that is attached to the inner side of the vertical plate and places it on the positioner tooling platform. The positioner tooling platform automatically positions and clamps the sub-component that is attached to the inner side of the vertical plate.

[0018] The welding robot performs spot welding on the remaining parts;

[0019] The transfer mechanism of the vertical plate welding robot or the transfer mechanism of the bottom plate welding robot grabs the process tie rod and places it on the secondary positioning table for positioning. The transfer mechanism of the vertical plate welding robot or the transfer mechanism of the bottom plate welding robot grabs the process tie rod from the secondary positioning table and places it on the designated position of the vertical plate. The welding robot performs spot welding on the process tie rod.

[0020] During the assembly process of structural components or before unloading after assembly, a material information identification device is used to mark the fixed position of the workpiece with inkjet coding for material information identification or collection in subsequent processes.

[0021] After the assembly is completed, the gantry robot will unload the parts and transfer them to the RGV buffer rack.

[0022] Furthermore, a vision camera is installed on the tooling. The vision camera is used to identify the model, posture and orientation of the workpiece in order to locate the workpiece.

[0023] Based on the same inventive concept, the present invention provides an automatic assembly and welding system for medium and heavy plates based on vision technology. The system uses the above-mentioned automatic assembly and welding method for medium and heavy plates based on vision technology for assembly and welding.

[0024] The system includes a positioning tooling platform, on which two vertical plate splicing welding positioners are set at intervals. Each of the two vertical plate splicing welding positioners is connected to a vertical plate splicing fixture at the ends that are far apart from each other. A bottom plate splicing welding positioner is set at intervals behind the second vertical plate splicing fixture. The end of the bottom plate splicing welding positioner that is far away from the vertical plate splicing fixture is connected to the bottom plate splicing fixture.

[0025] The displacement tooling platform is equipped with a vertical plate welding robot transfer mechanism on one side and a bottom plate welding robot transfer mechanism on the other side.

[0026] Furthermore, the system includes assembly pair tooling, C-shaped moving and rotating ground rails, and assembly assembly point handling and transfer mechanism. The two assembly pair toolings are spaced apart. A C-shaped moving and rotating ground rail is set on one side of the assembly pair tooling, and an assembly assembly point handling and transfer mechanism is set on the other side.

[0027] Furthermore, the upright plate splicing fixture includes a bending upright plate slide assembly, a bending upright plate pressure head slide assembly, an upright plate clamping slide assembly, an upright plate fixture, and an upright plate positioning slide assembly, all fixedly installed on the first base plate.

[0028] The bending vertical plate slide assembly is fixedly installed at one end of the base plate, and the vertical plate clamping slide assembly is fixedly installed at the other end of the base plate. The bending vertical plate slide assembly and the vertical plate clamping slide assembly are parallel to each other.

[0029] Between the bending vertical plate slide assembly and the vertical plate clamping slide assembly, there is a bending vertical plate pressure head slide assembly and a vertical plate positioning slide assembly. The bending vertical plate pressure head slide assembly and the vertical plate positioning slide assembly are parallel to each other.

[0030] The bending plate pressure head slide assembly is equipped with a plate clamp.

[0031] Furthermore, the base plate splicing fixture includes a base plate moving slide assembly, a right moving pressure head assembly, a seat ring support assembly, a positioning slide assembly, and a left moving pressure head assembly;

[0032] Both the base plate moving slide assembly and the positioning slide assembly are fixedly installed on the second base plate, and the base plate moving slide assembly and the positioning slide assembly are parallel to each other.

[0033] Two sets of parallel platforms are provided on the second base plate. The platforms are parallel to the base plate moving slide assembly. A left moving pressure head assembly is provided at the left end of each platform and a right moving pressure head assembly is provided at the right end. The seat ring support assembly is installed between the two platforms.

[0034] Furthermore, the assembly tooling includes a right positioning component, a left positioning component, and a centering mechanism fixedly mounted on the third base plate;

[0035] Multiple sets of right positioning components are spaced apart on one side of the third base plate, and multiple sets of left positioning components are spaced apart on the other side of the third base plate, with the multiple sets of right positioning components corresponding to the multiple sets of left positioning components; the centering mechanism is located between the right positioning components and the left positioning components.

[0036] Furthermore, the system includes an AGV material system, which adopts an automated delivery mode for the transfer of turntable parts from the pallet buffer area to each workstation.

[0037] Furthermore, the system includes a gantry manipulator, which is equipped with various electromagnetic grippers to accommodate different types of components.

[0038] Beneficial effects: Compared with the prior art, the significant technical effects of this invention are as follows: Through the rational layout and design of the production line, the entire production line is guaranteed to be safe and smooth, with high production quality, convenient material transfer, and physical isolation between manual passages and equipment, solving the technical problem of excessive manual participation in traditional production lines and realizing intelligent manufacturing throughout the entire process; at the same time, the anti-deformation adaptive control of the welding process ensures high welding quality, effectively suppresses common defects such as angular deformation and bending deformation, and strictly controls the dimensional accuracy error of welded parts within ±0.1mm, greatly reducing rework and scrap caused by deformation exceeding tolerance; Attached Figure Description

[0039] Figure 1 This is a schematic flowchart of a welding anti-deformation adaptive control method disclosed in an embodiment of the present invention;

[0040] Figure 2 This is a schematic diagram illustrating the principle of welding reverse deformation.

[0041] Figure 3 This is a flowchart of an automatic assembly and welding method for medium-thick plates based on vision technology, as disclosed in an embodiment of the present invention.

[0042] Figure 4 This is a schematic diagram of the welding station for the upright plate, base plate, and seat ring components in this invention.

[0043] Figure 5 A structural diagram of the assembly point workstation;

[0044] Figure 6A structural diagram of the vertical panel splicing fixture;

[0045] Figure 7 A schematic diagram of the base plate splicing fixture;

[0046] Figure 8 This is a structural diagram of the tooling for the assembly. Detailed Implementation

[0047] The technical solution of the present invention will now be described in detail with reference to specific embodiments and accompanying drawings.

[0048] Example 1

[0049] like Figure 1 As shown, the welding anti-deformation adaptive control method of the present invention includes the following steps:

[0050] S1. Input information such as material physical properties, process parameters, and weldment geometry into the main control system;

[0051] S2. The temperature field, stress field and deformation field of the entire weldment are obtained by using the finite element analysis method. A large amount of temperature field, stress field and deformation field data are learned and analyzed to obtain the influence of temperature field, stress field and deformation field data on the deformation of the weldment. The welding deformation amount of the welding process is simulated and predicted by the finite element analysis method to improve the prediction accuracy and adaptability.

[0052] S3. The process database sends instructions to the bending plate pressure head slide assembly via the data interface. The control unit drives the servo motor to move the pressure head body in the bending plate pressure head slide assembly 502 according to the instructions. After the pressure head body in the bending plate pressure head slide assembly 502 contacts the plate, it applies pressure according to the preset pressure. Positioning is completed through the torque feedback of the servo motor, so that the plate produces a pre-deformation opposite to the predicted welding deformation.

[0053] S4. During welding, thermal stress causes positive deformation of the vertical plate. The pre-deformation pressure applied by the pressure head body cancels out the thermal stress that causes positive deformation, ensuring that the dimensional accuracy and shape of the vertical plate meet the requirements after welding.

[0054] S5. Compare the simulation prediction results of welding deformation obtained in step S2 with the actual measurement results. If there is a deviation, correct and optimize the parameters, assumptions or calculation methods in the welding process so that they can more accurately reflect the actual welding process and provide a reliable basis for welding anti-deformation control.

[0055] S6. The main control system continuously analyzes new welding production data, uncovers patterns, optimizes anti-deformation control strategies, and updates the database to meet complex welding requirements.

[0056] The main control system, as the core of the equipment system, is closely linked to the process database. Before welding, numerical simulation technology is used to input information such as the physical property parameters of the welding materials, welding process parameters, and the geometry and dimensions of the workpiece, constructing a mathematical model of the welding process. This model simulates the distribution and changes in the temperature field during welding, and then, based on the thermo-mechanical coupling relationship of the materials, calculates the deformation trend and amount of the workpiece at different stages, thus obtaining relatively accurate welding deformation prediction data. The clamping angle is then adjusted based on this deformation prediction data.

[0057] Example 2

[0058] like Figure 3 As shown, this embodiment discloses an automatic assembly and welding method for medium-thick plates based on vision technology, including the following steps:

[0059] (1) The AGV material system automatically transfers the materials in the parts buffer area to the workstation (excluding components that have been welded together).

[0060] The workstations include: automatic welding of upright plates and small parts, automatic welding of base plates and seat rings, automatic assembly of assemblies, and welding of processed small parts. After the materials arrive from the previous process, they are manually palletized using a KBK (crane), and then automatically transferred to the parts buffer area by AGVs.

[0061] (2) The truss robot grabs the base plate seat ring assembly, the upright plate assembly, and the small parts assembly from the workstation and places them on the positioner tooling platform. The upright plate splicing welding positioner 1 or the base plate splicing welding positioner 2 automatically positions and clamps the base plate seat ring assembly, the upright plate assembly, and the small parts assembly on the positioner tooling platform.

[0062] In this embodiment, a vision camera is installed on the positioner tooling platform. The vision camera is used to identify the model, posture and orientation of the workpiece in order to locate the workpiece.

[0063] (3) The transport robot picks up the sub-parts (excluding sub-parts that are attached to the inner side of the upright plate) from the workstation and places them on the secondary positioning table. The secondary positioning table positions the sub-parts. The transport robot picks up the sub-parts from the secondary positioning table and places them on the tooling. The tooling automatically positions and clamps the sub-parts that are not attached to the inner side of the upright plate.

[0064] (4) The welding anti-deformation adaptive control method described in Example 1 applies a pre-deformation pressure to the workpiece through the pressure head body. The pre-deformation pressure is used to offset the thermal stress during welding.

[0065] (5) The welding robot assembles and spot welds the base plate seat ring assembly, upright plate assembly, small parts assembly, and sub-parts that do not fit with the inner side of the upright plate on the positioner tooling platform in a predetermined order, and welds the weld seam to be covered on the inner side of the upright plate assembly.

[0066] (6) The truss robot grabs the sub-component (referring to the sub-component that is in contact with the inner side of the vertical plate) and places it on the positioner tooling platform. The positioner tooling platform automatically positions and clamps the sub-component that is in contact with the inner side of the vertical plate.

[0067] (7) The welding robot performs spot welding on the remaining parts;

[0068] (8) The vertical plate welding robot transfer mechanism 3 or the bottom plate welding robot transfer mechanism 4 grabs the process tie rod and places it on the secondary positioning table for positioning. The vertical plate welding robot transfer mechanism 3 or the bottom plate welding robot transfer mechanism 4 grabs the process tie rod from the secondary positioning table and places it on the designated position of the vertical plate. The welding robot performs spot welding on the process tie rod.

[0069] (9) During the assembly process of structural components or before unloading after the assembly is completed, a material information identification device is used to mark the fixed position of the workpiece with inkjet coding for material information identification or collection in subsequent processes.

[0070] (10) After the assembly is completed, the gantry robot will unload the parts and transfer them to the RGV buffer rack.

[0071] Example 3

[0072] like Figure 4 and Figure 5 As shown in the figure, this embodiment discloses an automatic assembly and welding system for medium and heavy plates based on vision technology. The system adopts the automatic assembly and welding method for medium and heavy plates based on vision technology described in Embodiment 2 for assembly and welding. The system includes a displacement tooling platform, a vertical plate splicing welding positioner 1, a bottom plate splicing welding positioner 2, a vertical plate welding robot transfer mechanism 3, a bottom plate welding robot transfer mechanism 4, a vertical plate splicing fixture 5, a bottom plate splicing fixture 6, an assembly assembly tooling 7, a C-shaped moving and rotating ground rail 8, an assembly splicing handling and transfer mechanism 9, an AGV material system, and a gantry robot.

[0073] Two vertical plate welding positioners 1 are spaced apart on the positioning fixture platform. Each of the two vertical plate welding positioners (1) is connected to a vertical plate splicing fixture 5 at its far end. A bottom plate welding positioner 2 is spaced apart behind the second vertical plate splicing fixture 5. The end of the bottom plate welding positioner 2 away from the vertical plate splicing fixture 5 is connected to a bottom plate splicing fixture 6. A vertical plate welding robot transfer mechanism 3 is set on one side of the positioning fixture platform, and a bottom plate welding robot transfer mechanism 4 is set on the other side. Two assembly group fixtures 7 are spaced apart. A C-shaped moving and rotating ground rail 8 is set on one side of the assembly group fixture 7, and an assembly splicing transport and transfer mechanism 9 is set on the other side.

[0074] like Figure 6As shown, the upright plate splicing fixture 5 includes a bending upright plate slide assembly 501, a bending upright plate pressure head slide assembly 502, an upright plate clamping slide assembly 503, an upright plate fixture 504, and an upright plate positioning slide assembly 505, all fixedly installed on the first base plate. A bending vertical plate slide assembly 501 is fixedly installed at one end of the base plate, and a vertical plate clamping slide assembly 503 is fixedly installed at the other end of the base plate. The bending vertical plate slide assembly 501 and the vertical plate clamping slide assembly 503 are parallel to each other. A bending vertical plate pressure head slide assembly 502 and a vertical plate positioning slide assembly 505 are provided between the bending vertical plate slide assembly 501 and the vertical plate clamping slide assembly 503. The bending vertical plate pressure head slide assembly 502 and the vertical plate positioning slide assembly 505 are parallel to each other, and the bending vertical plate pressure head slide assembly 502 is parallel to the bending vertical plate slide assembly 501. A vertical plate clamp 504 is provided on the bending vertical plate pressure head slide assembly 502.

[0075] After the AGV receives the material, the gantry robot precisely positions and grabs the upright plate. The upright plate positioning slide assembly 505 starts to adjust its position and provides a positioning reference. When the upright plate is near the tooling, the upright plate clamping slide assembly 503 clamps and fixes the upright plate. The transport robot grabs the small parts under the guidance of visual recognition, and the bending upright plate slide assembly 501 makes fine adjustments as needed. The transport robot delivers the small parts to the top of the upright plate, and the welding robot uses the bending upright plate pressure head slide assembly 502 to spot weld the small parts. After spot welding, the welding robot welds the upright plate weld seam, the upright plate clamp 504 stabilizes the upright plate, and the bending upright plate slide assembly 501 and the bending upright plate pressure head slide assembly 502 are adjusted as needed. After welding is completed, the upright plate clamping slide assembly 503 is released, the gantry robot grabs the assembly, the upright plate positioning slide assembly 505 returns to its initial position, and the assembly is transferred to the buffer rack.

[0076] The bending plate pressure head slide assembly 502 includes a pressure head body, a pressure plate, a servo motor, and a control unit. After receiving instructions from the main control system, the control unit transmits signals to the servo motor, which in turn drives the pressure head body. When the pressure head body contacts the workpiece, it applies pressure according to a preset pressure value. Torque feedback from the servo motor ensures workpiece positioning, causing the plate to undergo "pre-deformation" opposite to the predicted welding deformation direction. During welding, the welding thermal stress causes positive deformation in the plate, which is counteracted by the pre-deformation applied by the pressure head, thus controlling the welding deformation and ensuring that the dimensional accuracy and shape of the plate meet requirements after welding.

[0077] In addition, such as Figure 2As shown, the main control system analyzes newly accumulated data, optimizes the anti-deformation control strategy, and updates the database to continuously improve the system's control capabilities. During the welding process, real-time welding deformation is collected through the interface of the forming equipment; this data is promptly transmitted to the main control system and stored in the process database. Simultaneously, the main control system compares and analyzes this real-time data with existing data in the database to determine whether the current welding state deviates from expectations, and then makes corresponding adjustment decisions.

[0078] After welding is completed, the actual welding results are compared with the previous predictions. This step is a verification and feedback of the entire welding deformation control process. A detailed comparative analysis is performed between these actual data and the previously predicted deformation data. If the deviation is within the allowable range, it indicates that the initial prediction model and clamping angle adjustments were reasonable and effective. If the deviation exceeds the allowable range, further analysis of the causes is needed. This could be due to inaccurate parameter settings in the prediction model, failure to achieve the expected constraint effect during clamping, or fluctuations in process parameters during the actual welding process. Based on the identified causes, the entire welding deformation control process is optimized and improved. This includes adjusting the parameters of the prediction model, improving the clamping method, or strengthening process control during welding to more accurately control welding deformation and improve welding quality in subsequent welding operations.

[0079] As welding production continues, the process database constantly accumulates new data. The main control system possesses data analysis and learning capabilities, enabling in-depth analysis of this new data to uncover patterns and potential information. By comparing welding data from different batches and under different conditions, the main control system can continuously optimize the welding anti-deformation control strategy and update the optimized results in the process database. In this way, the process database will continuously improve over time, enhancing the equipment system's adaptive control capability against welding anti-deformation to adapt to increasingly complex and diverse welding requirements.

[0080] The visual recognition system is used for positioning during the automated assembly of structural components. Working in conjunction with a handling robot, it ensures precise placement of parts and stable visual recognition. The vision camera, equipped with a dedicated controller, automatically identifies the workpiece's model, posture, and orientation.

[0081] like Figure 7As shown, the base plate assembly fixture 6 includes a base plate moving slide assembly 601, a right moving pressure head assembly 602, a seat ring support assembly 603, a positioning slide assembly 604, and a left moving pressure head assembly 605. The base plate moving slide assembly 601 and the positioning slide assembly 604 are both fixedly mounted on the second base plate, and are parallel to each other. Two sets of parallel platforms are provided on the second base plate, parallel to the base plate moving slide assembly 601. A left moving pressure head assembly 605 is located at the left end of each platform, and a right moving pressure head assembly 602 is located at its right end. The seat ring support assembly 603 is installed between the two platforms.

[0082] When the AGV delivers the base plate and seat ring components, the gantry robot grabs the base plate, and the base plate moving slide assembly 601 and positioning slide assembly 604 work together to position it, and the tooling is automatically clamped; the transport robot grabs the seat ring under visual recognition guidance, assisted by the left moving pressure head assembly 605 and the right moving pressure head assembly 602, and the welding robot spot welds the seat ring to the base plate, with the seat ring support assembly 603 providing support; after the spot welding, the welding robot performs welding (only spot welding is performed when the two sections of the base plate are joined), and each component is adjusted as needed to ensure welding; after welding, the gantry robot transfers the components to the flipping machine, flips them, and then transfers them to the buffer rack or the assembly point station.

[0083] like Figure 8 As shown, the assembly assembly 7 includes a right positioning component 701, a left positioning component 702, and a centering mechanism 703, all fixedly mounted on the third base plate. Multiple sets of right positioning components 701 are spaced apart on one side of the third base plate, and multiple sets of left positioning components 702 are spaced apart on the other side of the third base plate, with the right positioning components 701 and left positioning components 702 corresponding to each other. The centering mechanism 703 is positioned between the right positioning components 701 and the left positioning components 702.

[0084] The AGV material handling system employs an automated delivery mode for transferring turntable components from the pallet buffer area to various workstations. The AGV carts in the system utilize a low-profile lifting mechanism, hydraulically or electrically lifted, driven by steering wheels, and employ omnidirectional movement and navigation via laser and QR codes. It supports omnidirectional motion control, including forward, backward, turning, and lateral movement, with smooth operation. Obstacles are detected using laser sensors, providing 360° coverage without blind spots.

[0085] The gantry robot is used for loading and unloading large materials such as the left and right uprights and base plates of the turntable, as well as small components after welding. It has three moving axes (X, Y, and Z) with a repeatability of no more than ±1mm. Its load capacity meets the requirements of various product models, and its range of motion should cover the entire workstation. The installation method of the gantry robot should be adapted to the site layout, and a safe distance should be maintained from surrounding hardware equipment and facilities within the working range. The external moving axes of the gantry robot are linked with the robot body of the welding station to ensure long-term safe and reliable use with stable accuracy.

[0086] The gripper matched with the gantry robot has the ability to grip all parts (except those gripped by the handling robot) at the welding stations of left and right upright plates and small parts, welding stations of base plates and seat ring small components, and assembly points. It is equipped with a variety of electromagnetic grippers to be suitable for different types of parts. During gripping, the gripper has no less than two contact surfaces with the workpiece and is located at the center of gravity of the workpiece to ensure safe and stable transfer of the workpiece. The gripping efficiency is adapted to the production cycle of the process.

[0087] The material information identification device is used to identify and collect material information of turntable structural components manufactured in the production line. This information data is simultaneously transmitted to the production line MES system and can be displayed on the information management system terminal to transmit production process information in real time. It also has the function of information interaction with the factory MES to realize data sharing among various processes. During the assembly process of structural components or before unloading after assembly, the material information identification device is used to mark the fixed position of the workpiece with inkjet code for material information identification in subsequent processes.

[0088] The overall process flow of the vision-based automatic assembly and welding system for medium and heavy plates of the present invention is as follows: AGV pallet buffering → automatic welding between upright plates and small parts, and automatic welding between base plates and seat rings → rotating the base plate and seat ring assembly 180° → buffering of upright plates and base plate small components → automatic assembly point insertion → buffering of assembly point → automatic welding of assembly.

[0089] Among them, the automatic welding of upright plates and small parts, and the automatic welding of bottom plates and seat rings refer to the process where parts are moved from the buffer area by the AGV material system to the automatic welding station. The gantry robot automatically grabs workpiece a to the positioning fixture platform. After the upright plate welding positioner 1 or the bottom plate welding positioner 2 completes the welding, the upright plate welding robot transfer mechanism 3 or the bottom plate welding robot transfer mechanism 4 automatically grabs the workpiece b to be welded and places it on workpiece a. The welding robot then welds workpiece b and workpiece a. After welding, the upright plate welding fixture 5 or the bottom plate welding fixture 6 performs the welding. Finally, the gantry robot automatically grabs the workpiece and moves it to the buffer rack. When final assembly is required, the gantry robot automatically grabs the workpiece from the buffer rack and moves it to the assembly welding fixture, and so on.

[0090] The automatic welding process for upright plates and small parts is as follows: AGVs move upright plates and small parts from the parts buffer area to the automatic welding station for upright plates and small parts → gantry robots automatically grab the upright plates to the positioner tooling platform → transport robots automatically grab the small parts to the upright plates → welding robots perform joint welding → gantry robots automatically grab the unloaded upright plate components and transport them to the buffer rack → gantry robots automatically grab the upright plate components from the buffer rack to the assembly joint tooling, and so on.

[0091] The automatic welding process of the base plate and seat ring is as follows: The AGV moves the base plate and seat ring from the parts buffer area to the automatic welding station of the base plate and seat ring → The gantry robot automatically grabs the base plate to the positioner tooling platform → The transport robot automatically grabs the seat ring to the base plate → The welding robot assembles and welds → The gantry robot grabs the base plate assembly to the flipping machine → The flipping machine flips the workpiece 180° (i.e., the seat ring is vertically facing down) → The gantry robot automatically grabs the base plate assembly and moves it to the buffer rack → The gantry robot automatically grabs the base plate assembly from the buffer rack to the assembly tooling, and so on.

[0092] The automated assembly process refers to the process where components are moved from the buffer area by the AGV material system to the automated assembly station. A gantry robot, a C-shaped rotating track 8, and an assembly assembly handling and transfer mechanism 9 work together to automatically pick up the materials and transfer them to the assembly assembly fixture 7. The right positioning component 701 and left positioning component 702 in the assembly assembly fixture 7 are located on opposite sides of the equipment and are used for lateral positioning of the workpiece. The centering mechanism 703 is located in the center of the equipment, enabling precise horizontal centering of the workpiece and ensuring the positional accuracy of the workpiece on the fixture platform. Then, a welding robot performs welding, and finally, the gantry robot transports the assembly to the buffer rack, and the cycle repeats.

[0093] The automated assembly process flow is as follows: AGV moves turntable parts from the parts buffer area to the automated assembly station → gantry robot and handling robot work together to automatically grab materials to the assembly fixture → welding robot assembles the assembly → gantry robot moves the assembly to the buffer rack, and so on.

Claims

1. A welding anti-deformation adaptive control method, characterized in that, include: Input the material physical properties, process parameters, and weldment geometry information into the main control system; The temperature field, stress field, and deformation field of the entire weldment are obtained by using the finite element analysis method. The temperature field, stress field, and deformation field data are then learned and analyzed to obtain the influence of the temperature field, stress field, and deformation field data on the deformation of the weldment. The welding deformation during the welding process is then simulated and predicted using the finite element analysis method. The process database sends instructions to the bending plate pressure head slide assembly. The control unit drives the servo motor to move the pressure head body in the bending plate pressure head slide assembly according to the instructions. After the pressure head body contacts the plate, it applies pressure according to the preset pressure. Positioning is completed through the torque feedback of the servo motor, so that the plate produces a pre-deformation opposite to the predicted welding deformation. During welding, thermal stress causes positive deformation of the vertical plate, and the pre-deformation pressure applied by the pressure head body cancels out the thermal stress that causes positive deformation. The simulation prediction results of welding deformation are compared with the actual measurement results. If there is a deviation, the parameters, assumptions or calculation methods in the welding process are corrected and optimized. We continuously analyze new welding production data, uncover patterns, optimize anti-deformation control strategies, and update the database.

2. A method for automatic assembly and welding of medium-thick plates based on vision technology, characterized in that, include: The AGV material handling system automatically transfers materials from the parts buffer area to the workstation; The truss robot grabs the base plate seat ring assembly, the upright plate assembly, and the small parts assembly from the workstation and places them onto the positioner tooling platform. The upright plate splicing welding positioner (1) or the base plate splicing welding positioner (2) automatically positions and clamps the base plate seat ring assembly, the upright plate assembly, and the small parts assembly on the positioner tooling platform. The transport robot picks up the sub-component that is not in contact with the inner side of the upright plate from the workstation and places it on the secondary positioning table. The secondary positioning table positions the sub-component. The transport robot picks up the sub-component from the secondary positioning table and places it on the tooling. The positioner tooling platform automatically positions and clamps the sub-component that is not in contact with the inner side of the upright plate. The welding anti-deformation adaptive control method described in claim 1 applies a pre-deformation pressure to the workpiece through the pressure head body. The pre-deformation pressure is used to offset the thermal stress during welding. The welding robot assembles and spot welds the base plate seat ring assembly, upright plate assembly, small parts assembly, and sub-parts that do not fit against the inner side of the upright plate on the positioner tooling platform in a predetermined sequence, and welds the weld seams that need to be covered on the inner side of the upright plate. The truss robot grabs the sub-component that is attached to the inner side of the vertical plate and places it on the positioner tooling platform. The positioner tooling platform automatically positions and clamps the sub-component that is attached to the inner side of the vertical plate. The welding robot performs spot welding on the remaining parts; The vertical plate welding robot transfer mechanism (3) or the bottom plate welding robot transfer mechanism (4) grabs the process tie rod and places it on the secondary positioning table for positioning. The vertical plate welding robot transfer mechanism (3) or the bottom plate welding robot transfer mechanism (4) grabs the process tie rod from the secondary positioning table and places it on the designated position of the vertical plate. The welding robot performs spot welding on the process tie rod. During the assembly process of structural components or before unloading after assembly, a material information identification device is used to mark the fixed position of the workpiece with inkjet coding for material information identification or collection in subsequent processes. After the assembly is completed, the gantry robot will unload the parts and transfer them to the RGV buffer rack.

3. The automatic assembly and welding method for medium-thick plates based on vision technology according to claim 2, characterized in that, The tooling is equipped with a vision camera, which is used to identify the type, posture and orientation of the workpiece in order to locate the workpiece.

4. An automatic assembly and welding system for medium-thick plates based on vision technology, characterized in that: The system uses the vision-based automatic assembly and welding method for medium and thick plates as described in claim 2 for assembly and welding. The system includes a positioning tooling platform, on which two vertical plate splicing welding positioners (1) are set at intervals. Each of the two vertical plate splicing welding positioners (1) is connected to a vertical plate splicing fixture (5) at the ends that are far apart from each other. A bottom plate splicing welding positioner (2) is set at intervals behind the second vertical plate splicing fixture (5). The end of the bottom plate splicing welding positioner (2) that is far away from the vertical plate splicing fixture (5) is connected to the bottom plate splicing fixture (6). The displacement tooling platform is provided with a vertical plate welding robot transfer mechanism (3) on one side and a bottom plate welding robot transfer mechanism (4) on the other side.

5. The automatic assembly and welding system for medium and heavy plates based on vision technology according to claim 4, characterized in that: The system includes assembly pair tooling (7), C-type moving and rotating ground rail (8) and assembly assembly point handling and transfer mechanism (9). Two assembly pair tooling (7) are set at intervals. A C-type moving and rotating ground rail (8) is set on one side of the assembly pair tooling (7), and an assembly assembly point handling and transfer mechanism (9) is set on the other side.

6. The automatic assembly and welding system for medium-thick plates based on vision technology according to claim 4, characterized in that: The upright plate splicing fixture (5) includes a bending upright plate slide assembly (501), a bending upright plate pressure head slide assembly (502), an upright plate clamping slide assembly (503), an upright plate fixture (504), and an upright plate positioning slide assembly (505) fixedly installed on the first base plate. The bending vertical plate slide assembly (501) is fixedly installed at one end of the base plate, and the vertical plate clamping slide assembly (503) is fixedly installed at the other end of the base plate. The bending vertical plate slide assembly (501) and the vertical plate clamping slide assembly (503) are parallel to each other. A bending plate pressure head slide assembly (502) and a plate positioning slide assembly (505) are provided between the bending plate slide assembly (501) and the plate clamping slide assembly (503). The bending plate pressure head slide assembly (502) and the plate positioning slide assembly (505) are parallel to each other, and the bending plate pressure head slide assembly (502) and the bending plate slide assembly (501) are parallel to each other. The bending plate pressure head slide assembly (502) is provided with a plate clamp (504).

7. The automatic assembly and welding system for medium and heavy plates based on vision technology according to claim 4, characterized in that: The base plate splicing fixture (6) includes a base plate moving slide assembly (601), a right moving pressure head assembly (602), a seat ring support assembly (603), a positioning slide assembly (604), and a left moving pressure head assembly (605). The base plate moving slide assembly (601) and the positioning slide assembly (604) are both fixedly installed on the second base plate, and the base plate moving slide assembly (601) and the positioning slide assembly (604) are parallel to each other; Two sets of parallel platforms are provided on the second base plate. The platforms are parallel to the base plate moving slide assembly (601). A left moving pressure head assembly (605) is provided at the left end of each platform, and a right moving pressure head assembly (602) is provided at the right end. The seat ring support assembly (603) is installed between the two platforms.

8. The automatic assembly and welding system for medium and heavy plates based on vision technology according to claim 5, characterized in that: The assembly assembly tooling (7) includes a right positioning component (701), a left positioning component (702), and a centering mechanism (703) fixedly mounted on the third base plate. Multiple sets of right positioning components (701) are spaced apart on one side of the third base plate, and multiple sets of left positioning components (702) are spaced apart on the other side of the third base plate, with the multiple sets of right positioning components (701) and multiple sets of left positioning components (702) corresponding to each other; the centering mechanism (703) is located between the right positioning components (701) and the left positioning components (702).

9. The automatic assembly and welding system for medium-thick plates based on vision technology according to claim 4, characterized in that: The system includes an AGV material system, which uses an automated delivery mode for the transfer of turntable parts from the pallet buffer area to each workstation.

10. The automatic assembly and welding system for medium-thick plates based on vision technology according to claim 4, characterized in that: The system includes a gantry manipulator, which is equipped with a variety of electromagnetic grippers to accommodate different types of components.

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