Welding control method and workpiece welding method

Abstract

The invention provides a welding control method and a workpiece welding method. The welding control method comprises the steps that three-dimensional images of a plurality of workpieces in a welding work area are obtained; and according to the three-dimensional image of the workpiece, position information and welding seam information of the workpiece are obtained. And according to the position information of the workpiece and the welding seam information, the first welding robot and the second welding robot are controlled to work in one of the multiple working modes. Wherein in at least one working mode, the first welding robot and the second welding robot are controlled to synchronously weld different weld joint areas of the target workpiece. And in at least one working mode, the first welding robot and the second welding robot are controlled to weld different target workpieces correspondingly.

Description

Technical Field

[0001] The present invention relates to the welding of port machinery, and particularly to a welding control method and a welding method for workpieces. Background Art

[0002] With the continuous progress of welding technology, welding robots are increasingly used in the field of intelligent manufacturing due to their advantages of stable quality, high efficiency, good repeatability, and strong flexibility. Usually, a playback robot is used to achieve welding.

[0003] In the production of large steel structures of port machinery, there are a large number of steel structure parts that need to be welded. These steel structure parts have the characteristics of a large number of workpiece types, small weld lengths, and limited welding space, which leads to a general welding organization method for large steel structure parts of port machinery being a welding operation condition for small batches and various types of workpieces, and the welding difficulty is relatively large.

[0004] However, the traditional playback robot is a robot that can repeatedly reproduce the operation program stored through teaching programming and relies on manual teaching. For the actual welding production of the above-mentioned small batches and various types of workpieces, the playback robot has low welding efficiency, does not have the ability of collaborative welding operation, and has a frequent need for teaching programming, making it difficult to be directly applied to actual welding production on a large scale. Summary of the Invention

[0005] The purpose of the present invention is to provide a welding control method and a welding method for workpieces, which can realize the collaborative operation of welding robots and improve the welding efficiency.

[0006] One aspect of the present invention provides a welding control method for controlling the welding workstation, which is used to weld workpieces of various specifications in the welding work area. The welding workstation includes a first welding robot and a second welding robot; the welding control method includes: obtaining three-dimensional images of multiple workpieces in the welding work area; obtaining the position information and weld information of the workpieces according to the three-dimensional images of the workpieces; controlling the first welding robot and the second welding robot to work in one of multiple working modes according to the position information and weld information of the workpieces; in at least one working mode, controlling the first welding robot and the second welding robot to synchronously weld different weld areas of the target workpiece; in at least one working mode, controlling the first welding robot and the second welding robot to weld different target workpieces respectively.

[0007] In one embodiment, obtaining three-dimensional images of multiple workpieces within the welding work area includes: determining the initial position and the end position of the welding work area; scanning from the initial position to the end position of the welding work area to obtain three-dimensional images of all the workpieces within the welding work area.

[0008] In one embodiment, in obtaining the position information and weld information of the workpiece based on the three-dimensional image of the workpiece, the weld information includes a combination of one or more of the weld position, weld length, number of welds, and weld form of the workpiece.

[0009] In one embodiment, controlling the first welding robot and the second welding robot to work in one of multiple working modes according to the position information and weld information of the workpiece includes: determining the working modes of the first welding robot and the second welding robot; in this working mode, determining the motion trajectory planning of the first welding robot and the second welding robot based on the position information and weld information of the workpiece; and controlling the first welding robot and the second welding robot to perform welding operations according to the motion trajectory planning.

[0010] In one embodiment, in each working mode, the welding workload, arc starting time, and arc stopping time of the first welding robot and the second welding robot are the same.

[0011] In one embodiment, in this working mode, determining the motion trajectory planning of the first welding robot and the second welding robot based on the position information and weld information of the workpiece includes: in this working mode, based on a grid map or a topological map, determining a collision-free path of the first welding robot and the second welding robot from the welding starting point to the welding end point according to the position information of the workpiece; according to the collision-free path, determining a continuous motion sequence of the first welding robot and the second welding robot that satisfies dynamic constraints, where the continuous motion sequence includes time, motion speed, and motion acceleration; and taking the collision-free path and the continuous motion sequence as the motion trajectory planning.

[0012] In one embodiment, controlling the first welding robot and the second welding robot to perform welding operations according to the motion trajectory planning includes: positioning the starting point and the included angle position of the weld to obtain the starting point and the included angle position information of the weld; combining the starting point and the included angle position information of the weld and the motion trajectory planning to determine the weld welding trajectory of the first welding robot and the second welding robot; and controlling the first welding robot and the second welding robot to reach the target welding position and perform welding operations according to the weld welding trajectory.

[0013] In one embodiment, the control of the first welding robot and the second welding robot to perform welding operations according to the motion trajectory planning further includes: during the execution of the welding operation, an arc tracking method is used to track the real-time trajectories of the first welding robot and the second welding robot to obtain the welding angle deviation after arc ignition; and correcting the welding angle deviation.

[0014] Another aspect of the present invention provides a welding method for a workpiece, using a welding workstation to weld the workpiece; the welding method includes: spot welding the workpiece; hoisting the workpiece after spot welding into the welding working area; and using the welding control method described in any one of the above embodiments to control the welding workstation to weld the workpiece.

[0015] In one embodiment, the workpiece is the inner partition of a large box girder.

[0016] The welding control method of the present invention uses different working modes to control the target welding workpieces of the first welding robot and the second welding robot, allocate welding tasks to the first welding robot and the second welding robot, and perform coordinated control on both, effectively avoiding the idle rate during robot operation and greatly improving the welding operation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and other features, properties, and advantages of the present invention will become more apparent from the following description in conjunction with the drawings and embodiments, where:

[0018] Figure 1 is a schematic diagram of an embodiment of a welding workstation;

[0019] Figure 2 is Figure 1 the front view of the welding workstation shown;

[0020] Figure 3 is Figure 1 the top view of the welding workstation shown;

[0021] Figure 4 is Figure 1 the side view of the welding workstation shown;

[0022] Figure 5 is Figure 1 the three-dimensional structure schematic diagram of the welding workstation shown;

[0023] Figure 6 is Figure 1 the schematic diagram of the visual recognition mechanism of the welding workstation shown;

[0024] Figure 7 is Figure 1 the position schematic diagram of the visual positioning mechanism of the welding workstation shown;

[0025] Figure 8 is a schematic diagram of an embodiment of a welding system;

[0026] Figure 9 is a flowchart of a welding control method for controlling a welding workstation as shown in Figure 1 accordance with the present invention;

[0027] Figure 10 is a flowchart of a welding method for a workpiece according to the present invention;

[0028] Figure 11 is a schematic diagram of a welding working area of an inner partition of a large box girder;

[0029] Figure 12 is a schematic diagram of a vision recognition mechanism scanning the inner partition;

[0030] Figure 13 is a schematic diagram of a first welding robot and a second welding robot welding the inner partition. Detailed Embodiments

[0031] Now, embodiments of the present invention will be described in detail, with one or more examples shown in the accompanying drawings. Each example is provided to explain the present invention, not to limit the present invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the scope or spirit of the present invention. For example, features shown or described as part of one embodiment can be used with another embodiment to yield yet another embodiment. Accordingly, the present invention is intended to cover such modifications and variations that fall within the scope of the appended claims and their equivalents.

[0032] The welding workstation of the present invention is used to weld workpieces of various specifications within a welding working area. Among them, workpieces of various specifications refer to multiple workpieces having two or more specifications. Each workpiece does not need to be precisely positioned and can be located within the welding working area, and there is no overlapping part between the workpieces.

[0033] Figures 1 to 5 An embodiment of the welding workstation 10 of the present invention is shown. The welding workstation 10 of the present invention includes a gantry 100, a welding mechanism, a vision recognition mechanism 300, and a vision positioning mechanism 400. Among them, the gantry 100 can move relative to the welding working area 1 to achieve welding operations within the entire welding working area 1. The gantry 100 includes a cross beam 110, and the cross beam 110 is located above the welding working area 1. The welding mechanism includes a first welding robot 201 and a second welding robot 202 movably disposed at the lower end of the cross beam 110, and the first welding robot 201 and the second welding robot 202 can move relative to the gantry 100 respectively. AsFigure 2 and Figure 5 As shown in Figure 2 and Figure 5 , the first welding robot 201 and the second welding robot 202 are hung upside down on the gantry 100. The two work together to complete the welding operation, which can minimize the workload of workers and improve the utilization rate of the welding robots. The structures of the first welding robot 201 and the second welding robot 202 are the same.

[0034] The visual recognition mechanism 300 is arranged on the cross beam 110. The visual recognition mechanism 300 is used to scan multiple workpieces in the welding working area 1, generate a three-dimensional image, and obtain the position information and weld seam information of the workpieces. The visual recognition mechanism 300 performs intelligent panoramic recognition. By scanning the workpieces to generate a three-dimensional image, it can intelligently identify and locate the types and components included in the workpieces, and then identify the weld seams and complete the relevant positions of the weld seams.

[0035] The visual positioning mechanism 400 is arranged at the ends of the first welding robot 201 and the second welding robot 202. The visual positioning mechanism 400 is used to track the movement trajectories of the first welding robot 201 and the second welding robot 202 in real time. The visual positioning mechanism 400 can collect laser vision data and process the collected data, so as to accurately locate the starting point and wrap angle position of the weld seam before welding, and guide the first welding robot 201 or the second welding robot 202 to reach the welding position. During the welding process, the arc tracking method is adopted to track the weld seam path in real time to ensure the stability of the welding process and the beautiful formation of the weld seam.

[0036] The welding workstation 10 of the present invention collects the three-dimensional images of the workpieces through the visual recognition mechanism 300, and tracks the movement trajectories of the first welding robot 201 and the second welding robot 202 in real time through the visual positioning mechanism 400, realizes the automatic welding of workpieces of various specifications, without offline programming and manual on-line teaching, and the collaborative operation of the two welding robots can improve the welding efficiency.

[0037] In an embodiment, the welding workstation 10 further includes a transmission device, a control device, a safety protection device, a digital software system, and an environmental protection dust removal device 510. As Figure 2 shown, a welding power supply 520, a wire barrel 530, a cooling device 550, a control cabinet 540, and an environmental protection dust removal device 510 are arranged on the control platform 113 above the cross beam 110 of the gantry 100. The wire barrel 530 is used to store welding wires. A smoke collection hood 511 is arranged on the side of the cross beam 110 for collecting the smoke generated during the welding process; the environmental protection dust removal device 510 is communicated with the smoke collection hood 511 to reduce the pollution of the smoke.

[0038] Continue to refer to Figures 1 to 5, both the welding working area 1 and the welding workstation 10 are located on the concrete platform 590. The welding workstation 10 further includes a ladder 560, a jib crane 570, and an operating platform 580. The ladder 560 connects the control platform 113 and the operating platform 580 to facilitate the passage of operators.

[0039] In one embodiment, there are multiple visual recognition mechanisms 300, and the multiple visual recognition mechanisms 300 are fixed to the lower end of the crossbeam 110 of the gantry 100. As Figure 3 shown, the crossbeam 110 is arranged along the first direction A, and the multiple visual recognition mechanisms 300 are arranged at intervals along the first direction A. Among them, the welding working area 1 is generally rectangular, the first direction A is defined as the width direction of the welding working area 1, and the second direction B perpendicular to the first direction A is the length direction of the welding working area 1. Arranging the crossbeam 110 along the first direction A can reduce the span of the gantry 100.

[0040] As Figure 2 shown, the number of the visual recognition mechanisms 300 can be selected as three, and a single scan can cover all effective welding areas within a width range of 9 meters, the workpiece detection accuracy ≤ 3mm, and the comprehensive scanning speed is 7m / min.

[0041] The visual recognition mechanism 300 of the welding workstation 10 of the present invention is used for collecting and processing 3D image data of workpieces, automatically identifying the positions of workpieces, and automatically generating weld information, and feeding the weld information parameters back to the control device. The control device communicates the planned welding path to the first welding robot 201 and the second welding robot 202. The first welding robot 201 and the second welding robot 202 automatically weld according to the welding path.

[0042] Figure 6 Shows the structure of an embodiment of the visual recognition mechanism 300. In the embodiment as Figure 6 shown, the visual recognition mechanism 300 includes a connecting member 310 and a 3D camera 320. Among them, the connecting member 310 connects the crossbeam 110 and the 3D camera 320. The 3D camera 320 is used for area scanning multiple workpieces in the welding working area 1, and then obtaining a highly restored color complete 3D point cloud of the workpieces.

[0043] Specifically, the 3D camera 320 in this embodiment is a large baseline line scan 3D camera, which uses a high-speed and high-frame-rate sensor to transmit to the FPGA, is equipped with an 850nm red light laser, and is equipped with an independent computing board to realize high-speed acquisition of the 3D point cloud of large-scale components with a large field of view, and can perform "coarse positioning + fine positioning" for multiple specifications and multiple quantities of workpieces in a large area. It can realize welding of multiple components placed in the working area at one time, weld multiple workpieces through a single scan, simplify the scanning operation process, improve the production efficiency of on-site welding operations, and reduce the difficulty of manual operation.

[0044] Figure 7 shows the structure of the first welding robot 201 or the second welding robot 202. In the embodiment as Figure 7 shown, the first welding robot 201 or the second welding robot 202 includes a moving base 210, a robotic arm 220, and a welding torch 230. Among them, the robotic arm 220 has joint axes, that is, six degrees of freedom, and can flexibly adjust its position and posture in three-dimensional space. Its repositioning accuracy is ±0.051 mm, and the load can reach 8 kg, which can meet the usage requirements of the large water-cooled welding torch 230 and can achieve welding of the workpiece in any posture within the effective width range of the welding working area 1.

[0045] The robotic arm 220 is arranged on the moving base 210, and the welding torch 230 is arranged at the end of the robotic arm 220. A first track (not shown) and a second track (not shown) are provided at the lower end of the cross beam 110 of the gantry 100. The first welding robot 201 can move on the first track, and the second welding robot 202 can move on the second track. The moving base 210 cooperates with the first track and the second track on the cross beam 110 of the gantry 100 respectively to drive the robotic arm 220 and the welding torch 230 to move.

[0046] The first track and the second track are arranged along the first direction A, that is, they are parallel to each other, and there is a gap between them, reducing the collision probability between the first welding robot 201 and the second welding robot 202. The lengths of the first track and the second track extending along the first direction A and the gap between them can be determined according to the actual welding working conditions and scenarios, and the present invention does not make any restrictions.

[0047] As Figure 7 shown, the vision positioning mechanism 400 is installed at the ends of the first welding robot 201 and the second welding robot 202, near the connection position of the robotic arm 220 and the welding torch 230. The vision positioning mechanism 400 can automatically perform precise weld seam positioning, and can track and correct the welding angle deviation in real time after arc ignition. During the welding process, methods such as arc tracking can be used to track the weld seam path in real time to ensure the stability of the welding process and the beautiful formation of the weld seam.

[0048] The vision positioning mechanism 400 can be selected as a three-dimensional vision sensor, adopting MEMS structured light technology, that is, low-power MEMS opto-mechanics + high-resolution sensor / RGB camera, which can quickly perform area array scanning to obtain a highly restored color complete three-dimensional point cloud (RBGD) of the workpiece. Combining with the embedded vision point cloud analysis algorithm, it can quickly identify more than 95% of complex 3D weld seam features such as lap joints and butt joints, and plan a complete welding process.

[0049] Refer to Figure 2 and Figure 5, in one embodiment, the welding workstation 10 further includes a wire feeder 610 and a gun cleaning device 620. The wire feeder 610 and the gun cleaning device 620 are disposed on the first welding robot 201 and the second welding robot 202, and move together with the first welding robot 201 or the second welding robot 202. The wire feeder 610 is used to convey welding wire to the welding torch 230, and the welding wire can be stored in the wire barrel 530.

[0050] In one embodiment, the welding workstation 10 further includes a first ground rail 710 and a second ground rail 720. The first ground rail 710 and the second ground rail 720 are arranged along the second direction B. The workpiece is laid flat in the welding working area 1 between the first ground rail 710 and the second ground rail 720 to meet the requirements of workshop production operations. The gantry 100 includes a first support structure 120 and a second support structure 130 connected to both sides of the cross beam 110. The first support structure 120 cooperates with the first ground rail 710, and the second support structure 130 cooperates with the second ground rail 720, so that the gantry 100 can move along the second direction B.

[0051] In a specific embodiment, the overall floor area of the welding workstation 10 is about 50m×12m, and the span of the cross beam 110 of the gantry 100 is 10m.

[0052] The control device of the welding workstation 10 of the present invention is integrated by relevant hardware and software such as a central console, a robot controller, a communication system, and a vision system, and is centrally controlled by the central console. By converting data such as workpiece image information and position information collected by the vision system into operation instructions and motion trajectories, and using the communication interface of the robot to control the robotic arm, it has functions such as independently performing welding planning and generating welding instructions, automatically allocating welding tasks for robots, and avoiding idle robots or mutual interference and collision. The control device can achieve accurate and rapid welding with autonomous programming, non-teaching, and one-key operation.

[0053] The welding workstation 10 of the present invention adopts welding information management technology for digital monitoring of equipment working status information and related information management; at the same time, the welding workstation 10 has functions of statistically analyzing basic data such as equipment welding man-hours, welding material quotas, and energy consumption, and can provide data basis for production plans, real-time production monitoring, equipment fault diagnosis, equipment maintenance management, etc., and can provide data support for equipment operators and managers.

[0054] The present invention adopts intelligent flexible robot technology and utilizes a vision recognition mechanism 300 and a vision positioning mechanism 400 to integrate an intelligent welding workstation 10 that simulates the collaborative operation of human hands, eyes, and brain, enabling the first welding robot 201 and the second welding robot 202 to autonomously execute a series of complex tasks. During welding, the workpiece can be randomly placed in the welding working area 1, and manual operation only requires simple remote control. The robot simultaneously performs a fully automated welding process of scanning extraction - docking recognition - path planning - precise welding, and executes the welding task completely automatically.

[0055] The welding workstation 10 of the present invention can meet the requirements of automatic recognition and positioning of weld seams in small-batch and multi-variety production modes, and automatically complete the trajectory planning and programming of the robot.

[0056] As Figure 3 and Figure 8 shown, the welding system of the present invention includes two welding workstations 10. Among them, the welding workstation 10 is the welding workstation 10 described in any one of the above embodiments. The two welding workstations 10 can operate simultaneously or alternately to improve the welding efficiency.

[0057] Continuing to refer to Figure 3 and Figure 8 , the welding working area 1 includes a first working area 11 and a second working area 12. During welding operations, one of the two welding workstations 10 is located in the first working area 11, and the other of the two welding workstations 10 is located in the second working area 12; or the two welding workstations 10 are simultaneously located in the first working area 11 or the second working area 12. By using a large-span gantry 100 that can move by itself, the gantry 100 reciprocates between the first working area 11 and the second working area 12, and the loading and unloading of workpieces and welding operations can be carried out alternately without affecting the production efficiency.

[0058] Figure 9 shows the welding control method for controlling the welding workstation of the present invention. Combining with the welding workstation described in the above embodiments, the welding control method of the present invention includes steps S100 to S300:

[0059] In step S100, three-dimensional images of multiple workpieces in the welding working area are obtained.

[0060] In step S200, based on the three-dimensional images of the workpieces, the position information and weld seam information of the workpieces are obtained.

[0061] In step S300, based on the position information and weld seam information of the workpieces, the first welding robot and the second welding robot are controlled to work in one of multiple working modes.

[0062] In at least one working mode, control the first welding robot and the second welding robot to synchronously weld different weld areas of the target workpiece, that is, control the two to weld the same workpiece synchronously. In at least one working mode, control the first welding robot and the second welding robot to weld different target workpieces respectively, that is, control the two to weld different workpieces simultaneously.

[0063] The welding control method of the present invention uses different working modes to control the target welding workpieces of the first welding robot and the second welding robot, allocate welding tasks to the first welding robot and the second welding robot, and perform collaborative control on the two, effectively avoiding the idle rate during robot operation and greatly improving the welding operation efficiency.

[0064] In each working mode, the welding workload, arc starting time, and arc stopping time of the first welding robot and the second welding robot are the same. That is to say, evenly distribute the welding workload of the first welding robot and the second welding robot, start the arcs of the two welding torches simultaneously, and stop the arcs simultaneously, ensuring that the welding workloads of the two welding torches are the same and improving the welding production efficiency.

[0065] In an embodiment, step S100 further includes steps S110 to S120:

[0066] In step S110, determine the initial position (which can be understood as the welding starting point) and the termination position (which can be understood as the welding ending point) of the welding working area.

[0067] In step S120, scan from the initial position of the welding working area to the termination position of the welding working area to obtain the three-dimensional images of all the workpieces within the welding working area. In this step, the gantry can be used to drive the vision recognition structure to move to achieve the scanning action, as Figure 11 and Figure 12 shown.

[0068] In step S200, the weld information specifically includes one or a combination of the weld position, weld length, weld quantity, and weld form of the workpiece. Among them, the weld form is the spatial shape and cross-sectional characteristics of the weld in the welded joint. Obtaining the above weld information can improve the welding quality.

[0069] In an embodiment, step S300 further includes steps S310 to S330:

[0070] In step S310, determine the working modes of the first welding robot and the second welding robot, that is, determine whether the two weld the same workpiece simultaneously or weld different workpieces simultaneously.

[0071] In step S320, in this working mode, based on the position information of the workpiece and the weld information, determine the motion trajectory planning of the first welding robot and the second welding robot.

[0072] In step S330, according to the motion trajectory planning, control the first welding robot and the second welding robot to perform welding operations, as Figure 13 shown.

[0073] In one embodiment, step S320 further includes steps S321 to S323:

[0074] In step S321, in this working mode, based on the grid map or topological map, according to the position information of the workpiece, determine the collision-free path of the first welding robot and the second welding robot from the welding start point to the welding end point in the given environment.

[0075] In step S322, according to the collision-free path, determine the continuous motion sequence of the first welding robot and the second welding robot that satisfies the dynamic constraints, where the continuous motion sequence includes time, motion speed, and motion acceleration. Among them, the dynamic constraints refer to the limitations on, for example, speed and / or acceleration.

[0076] In step S323, take the collision-free path and the continuous motion sequence as the motion trajectory planning.

[0077] Through control algorithms, such as PID (Proportional Integral Derivative), model predictive control, ensure that the first welding robot and the second welding robot execute according to the motion trajectory planning, and reduce the deviation between the actual motion and the theoretical trajectory.

[0078] Depth vision data can be used to construct a state data set and combined with large models (such as multi-modal large models, large-scale pre-trained models) to improve the control device's understanding of the environment and the accuracy of motion trajectory planning.

[0079] In one embodiment, step S330 further includes S331 to S335:

[0080] In step S331, locate the starting point and the included angle position of the weld to obtain the starting point and the included angle position information of the weld. In this step, the starting point of the weld can be accurately located by means of point / line laser detection.

[0081] In step S332, combine the starting point and the included angle position information of the weld and the motion trajectory planning to determine the weld welding trajectory of the first welding robot and the second welding robot.

[0082] In step S333, control the first welding robot and the second welding robot to reach the target welding position, and perform the welding operation according to the welding track of the weld seam.

[0083] In step S334, during the execution of the welding operation, adopt the arc tracking method to track the real-time trajectories of the first welding robot and the second welding robot, and obtain the weld bead deviation after arc starting. In this step, the laser tracking method can also be adopted to perform real-time tracking on the weld seam to ensure beautiful weld formation.

[0084] In step S335, correct the weld bead deviation.

[0085] In the welding control method of the present invention, the automatic calibration technology of the robot TCP (Tool Center Point) can be utilized. Through the fusion of algorithms and sensors, accurately calibrate the three-dimensional position and posture of the end tools of the first welding robot and the second welding robot relative to the base coordinate system, and eliminate mechanical errors, assembly errors and environmental interference.

[0086] Compared with manual calibration that relies on visual alignment, the error can reach the millimeter level; while the automatic calibration accuracy can be improved to within 0.1 mm. The traditional multi-point method takes more than 30 minutes, and the automatic calibration is shortened to be completed within 5 minutes without manual intervention.

[0087] Figure 10 An embodiment of the welding method of the workpiece of the present invention is shown. In the present invention, a welding workstation is used to weld the workpiece. As Figure 10 shown, the welding method includes steps S400 to S500:

[0088] In step S400, perform spot welding on the workpiece.

[0089] In step S500, hoist the workpiece after spot welding into the welding working area. The workpiece can be manually hoisted into the first working area, and the welding operation can be realized without precise positioning.

[0090] In step S600, use the welding control method to control the welding workstation to weld the workpiece.

[0091] After step S600, manually load the second working area again. After all the workpieces in the first working area are welded, control the welding workstation to walk to the second working area to automatically perform scanning, tracking and welding. At this time, manually flip the workpiece in the first working area for the next welding.

[0092] Loop the above process until all the workpieces in the first working area and the second working area are welded.

[0093] In one embodiment, the workpiece is the inner partition 2 of a large box girder, as Figures 11 to 13 shown. The inner partition 2 serves as the main strengthening member of the box girder.

[0094] However, currently, the fabrication of the inner partition 2 is mainly carried out by traditional manual welding or an automatic welding trolley, which results in high labor costs and heavy labor intensity.

[0095] The dimensional information of the inner partition 2 of the large box girder is shown in Table 1:

[0096]

[0097] Table 1 Dimensions of the inner partition 2 of the large box girder

[0098] According to the dimensional information in Table 1, inner partitions 2 of various specifications are arranged within the welding work area. By applying intelligent 3D scanning technology, the number and form of welds are automatically identified, the weld positions are obtained, the welding path is automatically planned, the welding program is automatically generated, and the welding of the inner partition 2 of the large box girder is automatically completed.

[0099] In the welding control method of the present invention and the welding method of the workpiece, by applying intelligent 3D scanning technology, the number and form of welds are automatically identified, the weld positions are obtained, the welding path is automatically planned, the welding program is automatically generated, and the welding of the inner partition 2 of the large box girder is automatically completed using the robot teaching-free technology.

[0100] Although the present invention is disclosed above in preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, any modifications, equivalent changes, and decorations made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention all fall within the protection scope defined by the claims of the present invention.

Claims

1. A welding control method, characterized in that: Used to control a welding workstation, the welding workstation is used to weld workpieces of various specifications in a welding work area, the welding workstation includes a first welding robot and a second welding robot; The welding control method comprises: Acquire three-dimensional images of multiple workpieces within a welding work area; According to the three-dimensional image of the workpiece, the position information and weld information of the workpiece are obtained; Controlling the first welding robot and the second welding robot to work in one of a plurality of working modes according to the position information of the workpiece and the weld information; In at least one working mode, the first welding robot and the second welding robot are controlled to synchronously weld different weld areas of the target workpiece; in at least one working mode, the first welding robot and the second welding robot are controlled to respectively weld different target workpieces.

2. The welding control method according to claim 1, characterized in that: The method of acquiring three-dimensional images of multiple workpieces in a welding working area includes: Determine the initial and final positions of the welding work area; The welding work area is scanned from an initial position to an end position of the welding work area to obtain a three-dimensional image of all workpieces in the welding work area.

3. The welding control method according to claim 2, characterized in that: In the step of obtaining the position information and weld information of the workpiece based on the three-dimensional image of the workpiece, the weld information includes a combination of one or more of the weld position, weld length, weld number and weld form of the workpiece.

4. The welding control method according to claim 3, characterized in that: The controlling the first welding robot and the second welding robot to operate in one of a plurality of operating modes according to the position information of the workpiece and the weld information includes: Determining the working modes of the first welding robot and the second welding robot; In this working mode, the motion trajectory planning of the first welding robot and the second welding robot is determined according to the position information of the workpiece and the weld information; According to the motion trajectory planning, the first welding robot and the second welding robot are controlled to perform welding operations.

5. The welding control method according to claim 4, characterized in that: In each working mode, the welding workload, arc starting time and arc stopping time of the first welding robot and the second welding robot are consistent.

6. The welding control method according to claim 4 or 5, characterized in that: In this working mode, the motion trajectory planning of the first welding robot and the second welding robot is determined according to the position information of the workpiece and the weld information, including: In this working mode, based on the grid map or the topological map, according to the position information of the workpiece, a collision-free path of the first welding robot and the second welding robot from the welding start point to the welding end point is determined; Determine a continuous motion sequence of the first welding robot and the second welding robot that satisfies dynamic constraints according to the collision-free path, wherein the continuous motion sequence includes time, motion speed, and motion acceleration; The collision-free paths and continuous motion sequences are used as motion trajectory planning.

7. The welding control method according to claim 6, characterized in that: The method of controlling the first welding robot and the second welding robot to perform welding operations according to the motion trajectory planning includes: Locate the starting point and wrap angle position of the weld to obtain the starting point and wrap angle position information of the weld; Determine the welding trajectories of the first welding robot and the second welding robot by combining the starting point and wrap angle position information of the weld and the motion trajectory planning; The first welding robot and the second welding robot are controlled to reach the target welding position, and the welding operation is performed according to the welding trajectory of the weld.

8. The welding control method according to claim 7, characterized in that: The controlling the first welding robot and the second welding robot to perform the welding operation according to the motion trajectory planning also includes: During the welding operation, the real-time trajectories of the first welding robot and the second welding robot are tracked by an arc tracking method to obtain the welding angle deviation after arc initiation; Correction of weld angle deviation.

9. A method for welding a workpiece, comprising welding the workpiece using a welding workstation; It is characterized in that The welding method comprises: Spot welding of workpieces; Lift the spot-welded workpiece into the welding work area; The welding workstation is controlled by the welding control method according to any one of claims 1 to 8 to weld the workpiece.

10. The welding method according to claim 9, characterized in that: The workpiece is an inner partition of a large box beam.

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