A welding method and system based on a welding robot

Abstract

The application provides a welding method and system based on a welding robot, and relates to the technical field of automatic welding.The welding method based on the welding robot comprises the following steps: acquiring welding seam information of a workpiece, generating a planning path according to the welding seam information, controlling the welding robot to travel along the workpiece and perform trial welding based on the planning path, acquiring first welding parameters of the welding robot in the trial welding process in real time, determining a welding gun position point that meets an alignment condition of a welding seam center line according to the first welding parameters, and making the welding gun of the welding robot weld the workpiece along the welding gun position point. The application reduces the requirement for the standardization of the workpiece during welding, can always keep welding above the welding seam center line, and guarantees the accuracy of automatic welding.

Description

Technical Field

[0001] This invention relates to the field of automated welding technology, and more specifically, to a welding method and system based on a welding robot. Background Technology

[0002] Welding is an extremely important processing technology in the manufacturing process. It has many advantages over other processing technologies and is widely used in various important fields such as aerospace, shipbuilding, electronics and information, automobiles, bridges, marine drilling and building steel structures. Welded structures account for about 45% of the steel production of major industrial countries in the world each year.

[0003] When welding workpieces such as bridge diaphragms, current welding operations are mostly manual, supplemented by automated welding. Traditional automated welding mainly relies on a combination of robots and human instruction. Existing welding methods have the following main drawbacks: they require high standardization of workpieces, workpieces in the same batch often need to be of the same specifications, and welding deviations are prone to occur during the welding process. Summary of the Invention

[0004] The problem this invention aims to solve is that when welding workpieces such as bridge diaphragms, traditional automated welding has high requirements for workpiece standardization and is prone to welding deviations during the welding process.

[0005] To address the above problems, this invention provides a welding method based on a welding robot, comprising:

[0006] Obtain weld information of the workpiece;

[0007] A planned path is generated based on the weld information;

[0008] Based on the planned path, the welding robot is controlled to move along the workpiece and perform trial welding.

[0009] The first welding parameters of the welding robot during the trial welding process are acquired in real time.

[0010] The welding torch position point that meets the alignment conditions of the weld centerline is determined according to the first welding parameters, so that the welding torch of the welding robot welds the workpiece along the welding torch position point.

[0011] Optionally, controlling the welding robot to travel along the workpiece and perform trial welding based on the planned path includes:

[0012] The travel task containing the planned path is sent to the robot control subsystem, so that the robot control subsystem controls the welding robot to travel along the planned path, and controls the welding torch to perform trial welding alternately on both sides of multiple welding torch follower points during the travel of the welding robot. The welding torch follower points are the positions that the welding torch passes through as the welding robot travels in the initial posture.

[0013] Optionally, determining the welding torch position point that meets the alignment conditions of the weld centerline based on the first welding parameters, so that the welding torch welds the workpiece along the welding torch position point, includes:

[0014] When the test welding is performed alternately on both sides of the multiple welding gun follower points, the welding feedback current on both sides of the welding gun follower points reported by the robot control subsystem is obtained.

[0015] The welding torch follow-up point corresponding to the difference between the welding feedback currents on both sides being less than a preset value is determined, and the determined welding torch follow-up point is taken as the welding torch position point.

[0016] The welding torch position point is sent to the robot control subsystem so that the robot control subsystem controls the welding torch to weld the workpiece along the welding torch position point.

[0017] Optionally, after determining the welding torch position point that meets the alignment conditions of the weld centerline based on the first welding parameters, so that the welding torch welds the workpiece along the welding torch position point, the method further includes:

[0018] Second welding parameters are obtained for the process of welding the workpiece by the welding torch along the welding torch position point;

[0019] Determine whether a welding abnormality has occurred based on the second welding parameter.

[0020] Optionally, after determining whether a welding abnormality has occurred based on the second welding parameters, the method further includes:

[0021] When a welding abnormality is detected based on the second welding parameters, the current welding stop position of the welding robot is determined by the PLC control subsystem.

[0022] The vision subsystem determines the welding status corresponding to the current welding stop position and sends the welding status to the PLC control subsystem.

[0023] The robot control subsystem clears the abnormal state of the welding robot and sends an abnormality clearing completion signal to the PLC control subsystem, so that the PLC control subsystem reports the current welding stop position, the abnormality clearing completion signal, and the welding status.

[0024] A welding reset task is generated based on the current welding stop position, the anomaly clearance completion signal, and the welding status.

[0025] The welding reset task is sent to the robot control subsystem so that the welding robot can restart welding based on the current welding stop position.

[0026] Optionally, obtaining the weld information of the workpiece includes:

[0027] The gantry mechanism is controlled to drive the 3D camera to move along a preset path to perform a panoramic scan of the workpiece;

[0028] Based on the scanning results, the weld information of the workpiece is extracted.

[0029] Optionally, before obtaining the weld information of the workpiece, the method further includes:

[0030] Acquire the positioning image of the workpiece within the workbench area;

[0031] Based on the positioning image, determine whether the workpiece within the workbench area meets the initial positioning conditions;

[0032] If so, an initialization signal is sent to the PLC control subsystem so that the PLC control subsystem initializes each welding preparation action in the workbench area and feeds back the initialization confirmation instruction.

[0033] Based on the initialization confirmation instruction, generate pending confirmation information for job initiation and display the pending confirmation information.

[0034] Optionally, after generating the planned path based on the weld information, the method further includes:

[0035] The status detection command is sent to the PLC control subsystem so that the PLC control subsystem can determine whether the workbench area meets the welding operation conditions based on the acquired PLC external signals.

[0036] When the PLC control subsystem determines that the work area meets the welding operation conditions, it sends a welding operation start signal to the robot control subsystem through the PLC control subsystem, so that the welding robot can perform welding operation on the workpiece after receiving the initial welding task. The initial welding task includes the planned path.

[0037] When the PLC control subsystem determines that the working area does not meet the welding operation conditions, it receives and displays the abnormal signal fed back by the PLC control subsystem.

[0038] Compared with existing technologies, the present invention provides a welding method based on a welding robot. When welding workpieces such as bridge diaphragms, it acquires the weld seam information of the workpiece and generates a planned path for the welding robot based on the weld seam information. This eliminates or reduces the need for on-site teaching, meeting the requirements of intelligent welding. Based on the planned path, the welding robot is controlled to move along the workpiece and perform trial welding. The first welding parameters of the welding robot during the trial welding process are acquired in real time. Based on the first welding parameters, a welding torch position point that meets the alignment conditions of the weld seam centerline is determined, so that the welding torch is aligned with the workpiece along the welding torch position point. Welding is performed in this way, so even if the workpiece, such as the diaphragm, has errors or thermal deformation, different welding positions can be tried during the trial welding process to deal with the deformed welds of different workpieces. This allows for feedback and verification of the first welding parameters corresponding to different welding positions, thereby determining the welding torch position point. This reduces the requirements for workpiece standardization, and the welding torch position point is a position point that meets the alignment conditions of the weld center line. Thus, the line connecting multiple welding position points is parallel to the weld center line. Based on this welding position point, the welding torch can always be effectively positioned above the weld center line under control, ensuring the accuracy of automatic welding.

[0039] In another aspect, the present invention also provides a welding system based on a welding robot, comprising:

[0040] The host computer is used to acquire the weld information of the workpiece, generate a planned path based on the weld information, and also to send the planned path to the robot control subsystem.

[0041] The host computer is also used to: determine the welding gun position point that meets the alignment conditions of the weld centerline based on the first welding parameters fed back by the robot control subsystem, and send the welding gun position point to the robot control subsystem;

[0042] The robot control subsystem is used to receive the planned path issued by the host computer, and control the welding robot to move along the workpiece and perform trial welding based on the planned path. It is also used to obtain the welding torch position point issued by the host computer, and control the welding torch to weld the workpiece along the welding torch position point.

[0043] The welding system based on welding robots in this invention has similar technical effects to the welding methods based on welding robots described above, and will not be repeated here. Attached Figure Description

[0044] Figure 1 A schematic flowchart of a welding method based on a welding robot according to an embodiment of the present invention is shown;

[0045] Figure 2A schematic diagram of the structure of a partition member, taking a transverse partition as an example, is shown in an embodiment of the present invention;

[0046] Figure 3 An architecture diagram of a welding system based on a welding robot, as shown in an embodiment of the present invention, is illustrated.

[0047] Figure 4 A general flowchart illustrating the welding of the diaphragm in an embodiment of the present invention is shown;

[0048] Figure 5 A flowchart of welding anomaly handling in an embodiment of the present invention is shown.

[0049] Explanation of reference numerals in the attached figures:

[0050] 1-Host computer; 2-Vision subsystem; 3-PLC control subsystem; 4-Robot control subsystem. Detailed Implementation

[0051] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0052] It should be noted that relational terms such as "first" and "second" in this invention are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0053] In the description of this specification, references to terms such as "embodiment," "one embodiment," and "one implementation" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or implementation is included in at least one embodiment or illustrative implementation of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or implementation. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or implementations.

[0054] Diaphragms (diaphragm units) are structural members placed between beams to maintain cross-sectional shape and enhance lateral stiffness. Diaphragms are widely used in bridge steel structures with large spans or high load-bearing capacities. Diaphragm units consist of diaphragm transverse plates and diaphragm stiffeners, such as... Figure 2 The diagram shows the structure of the diaphragm, where L1 is the weld trajectory and L2 is the robot's teaching trajectory in the prior art. The teaching trajectory deviates significantly from the target path, especially when the workpiece experiences errors or thermal deformation, causing the weld to deform accordingly. This makes the teaching trajectory even more prone to deviation during the welding process. To address this issue, [the following is a proposed solution]... Figure 1 As shown, this embodiment of the invention proposes a welding method based on a welding robot.

[0055] The welding method based on the welding robot includes:

[0056] S10: Obtain weld information for the workpiece.

[0057] Specifically, weld information of a workpiece can be obtained manually and / or by machine. Combining manual methods can provide more comprehensive and accurate weld information. Manual methods involve obtaining and inputting weld information by checking the workpiece design drawings to view the weld location, shape, length, and other information, and conducting on-site inspections of the workpiece to directly observe the weld condition, including the welding position and type. Machine methods involve obtaining weld information by using a 3D camera to perform a panoramic scan of the workpiece to obtain 3D point cloud data or weld images. The point cloud data is then processed to identify the weld information.

[0058] S11: Generate a planned path based on the weld information.

[0059] Specifically, after obtaining the weld seam information, path planning can be performed based on all the extracted weld seam information. The planned path is used for the welding robot to drive the welding torch. Based on the aforementioned analysis and processing of the weld seam information, and according to the characteristics of the weld seam information, such as long weld seams and short weld seams, vertical weld seams and horizontal weld seams, the order of the welding path is determined, and the planned path is automatically generated without the need for manual teaching of the welding robot.

[0060] S12: Based on the planned path, control the welding robot to move along the workpiece and perform trial welding.

[0061] Specifically, appropriate welding parameters are set, including welding current range, welding voltage range, welding speed, etc., to control the movement of the welding robot. These parameters are all necessary and can be set by the operator. According to the planned path, the starting point and ending point of the planned path are located by the laser sensor, and the movement of the welding robot is controlled so that the welding torch moves along the surface of the workpiece, maintaining an appropriate welding distance and speed, and a trial welding is started. The trial welding is an exploratory welding and not the final formal welding to close the weld. The purpose of the trial welding is to obtain the first welding parameters to determine the welding torch position point that meets the alignment conditions of the weld centerline.

[0062] S13: Real-time acquisition of the first welding parameters of the welding robot during the trial welding process.

[0063] Welding parameters can be directly read using the circuit feedback system built into the welding robot. These parameters generally include real-time welding machine current, welding voltage, welding torch coordinates, and electrode extension length. The welding parameters can reflect the position of the welding torch and the distance between the end of the welding torch and the workpiece.

[0064] Since the planned path has been determined, during the trial welding process, the welding torch only needs to be adjusted to the initial position to be near the weld seam, so that the trial welding can be carried out without secondary positioning.

[0065] S14: Determine the welding torch position point that meets the alignment conditions of the weld centerline according to the first welding parameters, so that the welding torch welds the workpiece along the welding torch position point.

[0066] During the trial welding process, different welding positions are tried to obtain feedback on the first welding parameters corresponding to different welding positions and verify them, thereby determining the welding gun position point. The welding gun position point is the position point that meets the alignment conditions of the weld center line. After the welding environment is determined, the welding parameters of different welding gun positions are affected by the weld. For example, the larger the weld, the wider the weld, which corresponds to a larger welding voltage and welding current. Therefore, the welding gun position point that meets the alignment conditions of the weld center line can be determined based on the first welding parameters.

[0067] The welding torch position is determined in real time. That is, when the planned path passes near the weld position, multiple welding position points are determined. The line connecting these multiple welding position points is parallel to the weld centerline. Based on this welding position point, the welding torch can always be kept above the weld centerline to ensure welding without deviation and thus ensure welding accuracy.

[0068] Through the above steps, when welding workpieces such as bridge diaphragms, by acquiring the weld information of the workpiece and generating a planned path for the welding robot based on the weld information, on-site teaching can be reduced or eliminated, meeting the needs of intelligent welding. Based on the planned path, the welding robot is controlled to move along the workpiece and perform trial welding. The first welding parameters of the welding robot during the trial welding process are acquired in real time, and the welding torch position point that meets the alignment conditions of the weld centerline is determined based on the first welding parameters, so that the welding torch welds the workpiece along the welding torch position point. In this way, even for diaphragm-type workpieces… When workpieces exhibit errors or thermal deformation, different welding positions can be tried during trial welding to address the varying deformations of welds on different workpieces. This allows for feedback and verification of the first welding parameters corresponding to each welding position, thereby determining the welding torch position. This reduces the requirements for workpiece standardization, and the welding torch position is aligned with the weld centerline. Consequently, the line connecting multiple welding positions is parallel to the weld centerline. Based on this welding position, the welding torch, under control, can always effectively remain above the weld centerline for welding, ensuring the accuracy of automatic welding and improving welding quality.

[0069] like Figure 3 As shown below, the architecture diagram of the system to which this invention is applied is as follows:

[0070] 1) Intelligent layer: mainly includes host computer 1, which is equipped with a vision subsystem, host computer intelligent task planning system, robot welding program self-generation system, etc.

[0071] 2) Control layer: including vision subsystem 2, PLC control subsystem 3, robot control subsystem 4, etc.

[0072] 3) Execution layer: Its components correspond to vision subsystem 2, PLC control subsystem 3, and robot control subsystem 4, and include sensing and execution units such as sensors, motion control units, robot body, and welding system.

[0073] The following describes further implementation examples in conjunction with this architecture diagram.

[0074] As an optional embodiment of the present invention, generating the planned path based on the weld information includes:

[0075] Based on the weld information, multiple welding zones are determined.

[0076] Determine the welding sequence for each of the aforementioned welding zones.

[0077] The planned path is generated based on the welding sequence.

[0078] Specifically, the weld seam image is first identified, and all weld seams are divided into multiple welding zones, including vertical welding zones, horizontal welding zones, short welding zones, and long welding zones. Short and long welding zones are distinguished by the weld seam exceeding a set length. The welding sequence follows the principle of starting with vertical welding zones and then moving to horizontal welding zones. Both vertical and horizontal welding zones follow the principle of starting with short welding zones and then moving to long welding zones. Furthermore, welding is performed in a symmetrical order within both short and long welding zones, that is, starting from the middle and gradually welding symmetrically to both sides. Based on the above priorities, the welding sequence of each welding zone is determined. This welding sequence is also the main welding reference sequence for the welding torch and the reference sequence for the welding robot's walking path. Therefore, the planned path of the welding robot is determined.

[0079] As an optional embodiment of the present invention, controlling the welding robot to travel along the workpiece and perform trial welding based on the planned path includes:

[0080] The travel task containing the planned path is sent to the robot control subsystem, so that the robot control subsystem controls the welding robot to travel along the planned path, and controls the welding torch to perform trial welding alternately on both sides of multiple welding torch follower points during the travel of the welding robot. The welding torch follower points are the positions that the welding torch passes through as the welding robot travels in the initial posture.

[0081] Specifically, test welding is performed alternately on both sides of multiple welding torch follower points, that is, the welding torch is controlled to swing. The so-called swing is that the welding torch electrode and the welding point (weld edge) are at a certain angle (such as a right angle), and the welding torch moves back and forth horizontally while intermittently (test welding). The purpose of the test welding is to test the width of the weld based on the feedback current of the subsequent welding, so that the welding torch position is located directly above the center line of the weld.

[0082] As an optional embodiment of the present invention, determining the welding torch position point that meets the alignment conditions of the weld centerline based on the first welding parameters, so that the welding torch welds the workpiece along the welding torch position point, includes:

[0083] When the test welding is performed alternately on both sides of the multiple welding gun follower points, the welding feedback current on both sides of the welding gun follower points reported by the robot control subsystem is obtained.

[0084] The welding torch follow-up point corresponding to the difference between the welding feedback currents on both sides being less than a preset value is determined, and the determined welding torch follow-up point is taken as the welding torch position point.

[0085] The welding torch position point is sent to the robot control subsystem so that the robot control subsystem controls the welding torch to weld the workpiece along the welding torch position point.

[0086] In arc welding, the wire extension length is equal to the distance from the contact tip to the workpiece (weld edge) minus the arc length. Given a constant arc voltage, once the distance from the contact tip to the workpiece is determined, the wire extension length can also be determined.

[0087] In actual welding, under otherwise constant conditions, the welding feedback current and the welding extension length are approximately inversely proportional, such as... Figure 2 As shown, assuming the welding torch is directly above the weld centerline, the difference between the average values ​​of the left and right swing currents should be approximately zero. When the welding torch trajectory deviates from the weld centerline, a longer extension length on one side is required to complete the welding. Since the welding feedback current and the extension length are approximately inversely proportional, the welding feedback current on one side will be greater than that on the other side. Therefore, when the difference between the welding feedback currents on both sides of a certain welding torch position point is less than a preset value (in actual comparison of the difference, the larger welding feedback current is subtracted from the reduced welding feedback current, and the preset value is set to a positive value close to 0), the corresponding welding torch is approximately directly above the weld centerline, that is, the corresponding follower point is in the theoretically correct normal position, and this position point meets the welding requirements and should be taken as the welding torch position point.

[0088] For example, if the current on the left side of welding torch follower point A is A1 = 180A and the current on the right side is A2 = 210A, and the current on the left side of welding torch follower point B is B1 = 190A and the current on the right side is B2 = 198A, with a preset value of 10A, then welding torch follower point B is determined to be directly above (or close to) the weld centerline, and welding torch follower point B is taken as one of the welding torch position points. In actual welding, the position of the workpiece can be adjusted and fixed to adapt to the required welding method, such as flat welding or horizontal welding.

[0089] It should be noted that in practice, the coordinates of multiple consecutive welding torch tracking points under several consecutive welding test scenarios are usually taken and the average value is calculated to ensure the accuracy of the obtained welding torch position points and reduce random errors.

[0090] In this embodiment, the welding direction can be sensed and adjusted based on the difference in welding feedback current when swinging left and right (relative to the direction of weld advancement) during arc swinging, thereby ensuring that the welding torch position point is obtained, so that the welding torch is always kept on the center line of the weld and the weld is welded along the center line of the weld.

[0091] As an optional embodiment of the present invention, after determining the welding torch position point that meets the alignment conditions of the weld centerline according to the first welding parameters, so that the welding torch welds the workpiece along the welding torch position point, the method further includes:

[0092] Second welding parameters are obtained for the process of welding the workpiece by the welding torch along the welding torch position point;

[0093] Determine whether a welding abnormality has occurred based on the second welding parameter.

[0094] Specifically, the second welding parameter in the welding process can be obtained by real-time monitoring of parameters such as current, voltage, and temperature during the welding process using sensors. Assuming the second welding parameter is A, it can be determined whether a welding abnormality has occurred by comparing the second welding parameter A with a preset normal range. If A exceeds the normal range, it can be determined that a welding abnormality has occurred.

[0095] like Figure 5 As shown, referring to step S200, as an optional embodiment of the present invention, when a welding abnormality is determined to have occurred, the method further includes...

[0096] The current welding stop position of the welding robot is determined by the PLC control subsystem 3.

[0097] Position sensors are installed at appropriate locations within the working area of ​​the welding robot to monitor its position information in real time. The position sensors transmit the monitored position information to the PLC control subsystem 3. The PLC control subsystem 3 uses the data provided by the position sensors to accurately identify the current welding stop position of the welding robot.

[0098] The vision subsystem 2 determines the welding status corresponding to the current welding stop position and sends the welding status to the PLC control subsystem 3.

[0099] Visual sensors, or 3D sensors, can be installed at appropriate locations within the workbench area of ​​the welding robot to capture image information of the welding area. The vision subsystem 2 analyzes and processes the captured images to extract feature information of the welding area. Based on the extracted feature information, the vision subsystem 2 can classify the state of the welding area, such as normal welding, abnormal welding, welding interruption, etc. Once the vision subsystem 2 determines the welding state corresponding to the current welding stop position, it can feed this information back to the PLC control subsystem 3 and the robot control subsystem 4.

[0100] The robot control subsystem 4 clears the abnormal state of the welding robot and sends an abnormality clearing completion signal to the PLC control subsystem 3, so that the PLC control subsystem 3 reports the current welding stop position, the abnormality clearing completion signal, and the welding status.

[0101] The robot control subsystem 4 monitors the status of the welding robot and detects any abnormal states, such as positioning errors, welding interruptions, arc errors, power outages, and temporary stops. Once an abnormal state is detected, the robot control subsystem 4 executes corresponding clearing operations according to a pre-set abnormality handling algorithm, such as repositioning the welding robot or restarting the welding program. By controlling the actions and positions of the welding robot, the robot control subsystem 4 clears the abnormal state and restores the welding process to normal. When the abnormal state is successfully cleared, the robot control subsystem 4 sends an abnormality clearing completion signal to the PLC control subsystem 3 to notify the PLC control subsystem 3 that the welding robot has returned to normal working status.

[0102] A welding reset task is generated based on the current welding stop position, the anomaly clearing completion signal, and the welding status.

[0103] After receiving the relevant information, the host computer 1 will automatically resume welding from the current welding stop position to the arc cut-off position based on the position where the last task stopped and the welding state at the time of stop. The offset amount set for the arc cut-off position (the amount of translation in the welding line direction based on the arc cut-off position) can be used to specify the overlap of the weld and the remaining welding part. The welding reset task includes the offset amount and the welding line direction, and a new initial welding task is regenerated.

[0104] The welding reset task is sent to the robot control subsystem 4 so that the welding robot can restart welding based on the current welding stop position.

[0105] Through the above steps, the robot control subsystem 4 can clear the abnormal state of the welding robot and send an abnormality clearing completion signal to the PLC control subsystem 3. This ensures that the system can handle abnormal situations in a timely manner, guaranteeing the stability, reliability, and continuity of the welding process and improving welding efficiency.

[0106] As an optional embodiment of the present invention, obtaining the weld information of the workpiece includes:

[0107] The gantry mechanism is controlled to drive the 3D camera to move along a preset path to perform a panoramic scan of the workpiece.

[0108] Based on the scanning results, the weld information of the workpiece is extracted.

[0109] like Figure 4As shown, referring to step S100, specifically, the path that the 3D camera needs to follow is determined to achieve a panoramic scan of the workpiece. This can be achieved through a pre-set trajectory or path planning algorithm. The control system is used to manipulate the gantry mechanism to move it according to the preset path, ensuring that the 3D camera can completely scan the entire workpiece. The 3D camera moves along the planned path to perform a panoramic scan of the workpiece, obtaining detailed information and images of the workpiece surface. A specially designed weld seam recognition algorithm is used to analyze and process the scan results to extract weld seam information on the workpiece. This algorithm usually combines image processing, pattern recognition, and machine learning algorithms. Based on the output of the weld seam recognition algorithm, the weld seam information of the workpiece is extracted, including key parameters such as the position, length, width, and shape of the weld seam.

[0110] By implementing the above steps, a panoramic scan of the workpiece can be achieved, thereby automatically acquiring key parameters to facilitate path calculation and planning.

[0111] As an optional embodiment of the present invention, before obtaining the weld information of the workpiece, the method further includes:

[0112] Obtain the positioning image of the workpiece within the workbench area.

[0113] With the help of a 3D camera and a gantry mechanism, the 3D camera can acquire the positioning image of the workpiece directly above the worktable area and send the positioning image to the PLC control subsystem 3 for initial positioning judgment.

[0114] Based on the positioning image, determine whether the workpiece in the workbench area meets the initial positioning conditions.

[0115] The acquired positioning image is preprocessed, including denoising, grayscale conversion, and edge detection, to better identify the workpiece. Features such as the shape, size, and placement angle of the workpiece are extracted from the preprocessed image. The extracted features are compared with the predefined initial positioning conditions to determine whether the workpiece meets the requirements. If the difference between the feature items meets the preset deviation range, it is determined that the conditions are met.

[0116] If so, an initialization signal is sent to the PLC control subsystem 3 so that the PLC control subsystem 3 initializes each welding preparation action in the workbench area and feeds back the initialization confirmation instruction.

[0117] Each welding preparation action includes the initial equipment status, the initial posture of the welding robot, the initial scanning working position of the gantry, and the program running status. After the PLC control subsystem 3 maintains communication with the corresponding equipment and welding robot, it activates the initial status, generates an initialization confirmation instruction, and reports the initialization confirmation instruction. The human-machine interaction signals of each operation in the above intermediate stages are processed by the lower computer (PLC).

[0118] Based on the initialization confirmation instruction, generate pending confirmation information for job initiation and display the pending confirmation information.

[0119] The initialization confirmation command can be received and displayed on the host computer 1, and a prompt can be generated. The prompt on the host computer 1 interface allows the operator to complete the initialization by pressing the initialization button.

[0120] Through the above process, the initial positioning conditions of the workpiece in the workbench area can be determined, and corresponding human-computer interaction operations can be performed based on the results to ensure the smooth progress of the welding preparation process.

[0121] As an optional embodiment of the present invention, after generating the planned path, in order to ensure the normal progress of the welding process, the cooperation of peripheral sub-devices and corresponding sensors is required. Therefore, this embodiment also proposes a detection embodiment after generating the planned path, which further includes:

[0122] The status detection command is sent to the PLC control subsystem 3 so that the PLC control subsystem 3 can determine whether the workbench area meets the welding operation conditions based on the acquired PLC external signals.

[0123] Most of the sensors used for peripheral detection and the processing of human-machine interaction signals are handled by the PLC. A small number of sensors and sub-devices are directly connected to the welding robot. The PLC and robot control subsystem 4 can automatically acquire the external signals of these sensors or sub-devices, i.e., PLC external signals, based on the received status detection instructions, and determine whether the PLC external signals are normal or not. Peripheral sensors include emergency stop sensors (auxiliary sensors), grating sensors, etc.

[0124] External monitoring includes peripheral sensors, grating sensors, and signals from manually operated buttons.

[0125] When the host computer 1 receives signals such as sensor malfunction, sub-device malfunction, grating trigger signal, or manual emergency stop and stop, it can promptly perform an emergency stop or display a message indicating that the malfunction needs to be processed.

[0126] When the PLC control subsystem 3 determines that the work area meets the welding operation conditions, it sends a welding operation start signal to the robot control subsystem 4 so that the welding robot can perform welding operations on the workpiece after receiving the initial welding task. The initial welding task includes the planned path.

[0127] When the PLC external signal is normal, it indicates that the sensors and sub-devices used for peripheral detection are normal and can cooperate with the welding robot to perform welding. This indicates that the welding operation can be started. At this time, the lower PLC of the PLC control subsystem 3 will send a welding operation start signal to the robot.

[0128] When the PLC control subsystem 3 determines that the working area does not meet the welding operation conditions, it receives and displays the abnormal signal fed back by the PLC control subsystem 3.

[0129] Conversely, if the conditions for welding operations are not met, the PLC control subsystem 3 will report an abnormal signal, indicating that at least one of the sensors and sub-devices used for peripheral detection has a problem. At this time, the PLC can transmit the abnormal signal to the host computer 1, which will display it through the human-machine interface of the host computer 1. At this time, human intervention is required for targeted processing.

[0130] On the other hand, a welding system based on a welding robot, applying the welding method based on a welding robot as described in any of the above embodiments, includes:

[0131] The host computer 1 is used to acquire the weld information of the workpiece, generate a planned path based on the weld information, and also to send the planned path to the robot control subsystem 4.

[0132] The host computer 1 is also used to: determine the welding gun position point that meets the alignment conditions of the weld center line according to the first welding parameters fed back by the robot control subsystem 4, and send the welding gun position point to the robot control subsystem 4.

[0133] The robot control subsystem 4 is used to receive the planned path issued by the host computer 1, and control the welding robot to move along the workpiece and perform trial welding based on the planned path. It is also used to obtain the welding gun position point issued by the host computer 1, and control the welding gun to weld the workpiece along the welding gun position point.

[0134] The specific implementation process of this embodiment can be referred to the first embodiment mentioned above, and will not be described again here.

[0135] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided by this invention can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and RAMbus dynamic RAM (RDRAM), etc.

[0136] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features of the invention herein.

[0137] While the present invention has been disclosed above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and all such changes and modifications will fall within the scope of protection of the present invention.

Claims

1. A welding method based on a welding robot, characterized in that, include: Obtain weld information of the workpiece; A planned path is generated based on the weld information; Based on the planned path, controlling the welding robot to move along the workpiece and perform trial welding includes: The travel task containing the planned path is sent to the robot control subsystem (4) so ​​that the robot control subsystem (4) controls the welding robot to travel along the planned path and controls the welding torch to perform trial welding alternately on both sides of multiple welding torch follower points during the travel of the welding robot. The welding torch follower points are the positions that the welding torch passes through as the welding robot travels in the initial posture. The first welding parameters of the welding robot during the trial welding process are acquired in real time. Determine the welding torch position point that meets the alignment conditions of the weld centerline based on the first welding parameters, so that the welding robot's welding torch welds the workpiece along the welding torch position point, including: When the welding torch performs trial welding on both sides of multiple welding torch follower points, the welding feedback current on both sides of the welding torch follower points reported by the robot control subsystem (4) is obtained. The welding torch follow-up point corresponding to the difference between the welding feedback currents on both sides being less than a preset value is determined, and the determined welding torch follow-up point is taken as the welding torch position point. The welding torch position point is sent to the robot control subsystem (4) so ​​that the robot control subsystem (4) controls the welding torch to weld the workpiece along the welding torch position point; After determining the welding torch position point that meets the alignment conditions of the weld centerline based on the first welding parameters, so that the welding torch welds the workpiece along the welding torch position point, the method further includes: Second welding parameters are obtained for the process of welding the workpiece by the welding torch along the welding torch position point; Determine whether a welding abnormality has occurred based on the second welding parameters; After determining whether a welding abnormality has occurred based on the second welding parameters, the method further includes: When a welding abnormality is detected based on the second welding parameters, the current welding stop position of the welding robot is determined by the PLC control subsystem (3). The vision subsystem (2) determines the welding status corresponding to the current welding stop position and sends the welding status to the PLC control subsystem (3). The robot control subsystem (4) clears the abnormal state of the welding robot and sends an abnormality clearing completion signal to the PLC control subsystem (3), so that the PLC control subsystem (3) reports the current welding stop position, the abnormality clearing completion signal and the welding status. A welding reset task is generated based on the current welding stop position, the anomaly clearance completion signal, and the welding status. The welding reset task is sent to the robot control subsystem (4) so ​​that the welding robot can re-weld based on the current welding stop position.

2. The welding method based on a welding robot according to claim 1, characterized in that, The acquisition of weld information of the workpiece includes: The gantry mechanism is controlled to drive the 3D camera to move along a preset path to perform a panoramic scan of the workpiece; Based on the scanning results, the weld information of the workpiece is extracted.

3. The welding method based on a welding robot according to claim 1 or 2, characterized in that, The step of generating a planned path based on the weld information includes: Based on the weld information, multiple welding zones are determined; Determine the welding sequence for each of the aforementioned welding zones; The planned path is generated based on the welding sequence.

4. The welding method based on a welding robot according to claim 1, characterized in that, Before obtaining the weld information of the workpiece, the method further includes: Acquire the positioning image of the workpiece within the workbench area; Based on the positioning image, determine whether the workpiece within the workbench area meets the initial positioning conditions; If so, an initialization signal is sent to the PLC control subsystem (3) so that the PLC control subsystem (3) initializes each welding preparation action in the workbench area and sends back an initialization confirmation instruction; Based on the initialization confirmation instruction, generate pending confirmation information for job initiation and display the pending confirmation information.

5. The welding method based on a welding robot according to claim 4, characterized in that, After generating the planned path based on the weld information, the method further includes: The status detection command is sent to the PLC control subsystem (3) so that the PLC control subsystem (3) can determine whether the workbench area meets the welding operation conditions based on the acquired PLC external signal. When the PLC control subsystem (3) determines that the workbench area meets the welding operation conditions, it sends a welding operation start signal to the robot control subsystem (4) through the PLC control subsystem (3) so that the welding robot can perform welding operation on the workpiece after receiving the initial welding task. The initial welding task includes the planned path. When the PLC control subsystem (3) determines that the workbench area does not meet the welding operation conditions, it receives and displays the abnormal signal fed back by the PLC control subsystem (3).

6. A welding system based on a welding robot, characterized in that, include: The host computer (1) is used to obtain the weld information of the workpiece and generate a planned path based on the weld information. It is also used to send the planned path to the robot control subsystem (4). The host computer (1) is also used to: determine the welding gun position point that meets the alignment conditions of the weld center line according to the first welding parameters fed back by the robot control subsystem (4), and send the welding gun position point to the robot control subsystem (4). The robot control subsystem (4) is used to receive the planned path issued by the host computer (1) and control the welding robot to move along the workpiece and perform trial welding based on the planned path. The subsystem includes sending the moving task containing the planned path to the robot control subsystem (4) so ​​that the robot control subsystem (4) controls the welding robot to move along the planned path and controls the welding torch to perform trial welding alternately on both sides of multiple welding torch follower points during the movement of the welding robot. The welding torch follower points are the positions that the welding torch passes through as the welding robot moves in the initial posture. It is also used to obtain the welding torch position point issued by the host computer (1) and control the welding torch to weld the workpiece along the welding torch position point, including: When the welding torch performs trial welding on both sides of multiple welding torch follower points, the welding feedback current on both sides of the welding torch follower points reported by the robot control subsystem (4) is obtained. The welding torch follow-up point corresponding to the difference between the welding feedback currents on both sides being less than a preset value is determined, and the determined welding torch follow-up point is taken as the welding torch position point. The welding torch position point is sent to the robot control subsystem (4) so ​​that the robot control subsystem (4) controls the welding torch to weld the workpiece along the welding torch position point; After determining the welding torch position point that meets the alignment conditions of the weld centerline based on the first welding parameters, so that the welding torch welds the workpiece along the welding torch position point, the method further includes: Second welding parameters are obtained for the process of welding the workpiece by the welding torch along the welding torch position point; Determine whether a welding abnormality has occurred based on the second welding parameters; After determining whether a welding abnormality has occurred based on the second welding parameters, the method further includes: When a welding abnormality is detected based on the second welding parameters, the current welding stop position of the welding robot is determined by the PLC control subsystem (3). The vision subsystem (2) determines the welding status corresponding to the current welding stop position and sends the welding status to the PLC control subsystem (3). The robot control subsystem (4) clears the abnormal state of the welding robot and sends an abnormality clearing completion signal to the PLC control subsystem (3), so that the PLC control subsystem (3) reports the current welding stop position, the abnormality clearing completion signal and the welding status. A welding reset task is generated based on the current welding stop position, the anomaly clearance completion signal, and the welding status. The welding reset task is sent to the robot control subsystem (4) so ​​that the welding robot can re-weld based on the current welding stop position.

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