Collaborative robot-based welding arc pressure tracking and arc swing control system and method

Abstract

The application discloses a welding arc pressure tracking and arc swing control system and method based on a collaborative robot. The device comprises a collaborative robot, a collaborative controller and an offset controller. The swing parameters and arc voltage of the collaborative robot are set according to the welding task and welding process requirements through the collaborative controller, the swing parameters are sent to the offset controller to control the collaborative robot to swing the arc, the actual arc voltage of the collaborative robot is compared with the set arc voltage, and the comparison result is sent to the offset controller to dynamically adjust the welding gun position of the collaborative robot to realize arc pressure tracking. The application utilizes the collaborative robot to realize arc swing and arc pressure tracking in the welding process, greatly reduces the use cost of the robot in the project, fully utilizes the flexibility of the robot, the robot can quickly and accurately respond to different welding task requirements, significantly improves the welding efficiency, improves the production efficiency, and greatly reduces the labor intensity of the operator.

Description

Technical Field

[0001] The present invention belongs to the technical field of welding robot control, and more specifically, relates to a welding arc voltage tracking and arc swing control system and method based on a collaborative robot. Background Art

[0002] Amidst the booming modern manufacturing industry, welding technology, as a key process in industrial production, has a profound impact on product quality and production efficiency through its automation and intelligentization. In the current application of specialized welding machines and industrial robots, TIG welding, with its outstanding advantages such as high weld quality and minimal deformation, is widely used in high-end manufacturing fields such as aerospace, electronics, and precision machinery. Furthermore, arc voltage tracking and arc oscillation technologies in TIG welding have also been achieved to a certain extent.

[0003] Specialized welding machines, with their mature design and manufacturing processes, offer a relatively low cost advantage. They can efficiently and stably complete welding tasks in scenarios requiring a relatively simple welding trajectory. However, their relatively fixed welding trajectory lacks flexibility. Faced with increasingly complex and diverse welding technology requirements, rapid adjustment of welding parameters and trajectories is difficult, limiting their application in welding complex structural parts.

[0004] Industrial robots, with their powerful programming capabilities and multi-axis linkage systems, offer highly flexible operation, adapting to a wide range of complex welding tasks and significantly improving welding quality and stability. However, industrial robots are expensive to purchase, and subsequent maintenance and upgrade costs are also significant. This represents a significant burden for small and medium-sized projects with limited budgets, resulting in significant financial pressure and obstacles for many small and medium-sized projects when introducing robots for welding operations.

[0005] In contrast, collaborative robots, with their compactness, flexibility, and affordable cost, have shown unique application potential in small and medium-sized projects. Consequently, there is an increasing demand for TIG welding arc voltage tracking and arc oscillation technologies implemented on collaborative robots.

[0006] The information disclosed in the background technology section of the present invention is only intended to deepen the understanding of the general background technology of the present invention, and should not be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to those skilled in the art. Summary of the Invention

[0007] The purpose of the present invention is to propose a welding arc voltage tracking and arc swing control system and method based on a collaborative robot, so as to solve the problems that the welding machine has a fixed trajectory and insufficient flexibility in TIG welding, and the industrial robot is expensive, both of which are not conducive to small and medium-sized projects. The invention realizes the arc voltage tracking and arc swing of TIG welding using a collaborative robot, so as to improve the flexibility of welding and reduce costs; and to achieve the improvement of productivity, the improvement of welding quality and the reduction of labor intensity.

[0008] To achieve the above objectives, in a first aspect, the present invention proposes a welding arc voltage tracking and arc swing control system based on a collaborative robot, comprising a collaborative robot, a collaborative controller and an offset controller;

[0009] The collaborative robot is used to generate a welding motion trajectory based on the welding task and welding process requirements, and perform the welding task based on the welding motion trajectory;

[0010] The collaborative controller is communicatively connected to the offset controller and the collaborative robot, respectively, and is used to: control the collaborative robot to start / stop performing the welding task according to the welding motion trajectory; set the swing parameters and arc voltage of the collaborative robot based on the welding task and welding process requirements, and send the swing parameters to the offset controller; and collect the actual arc voltage of the collaborative robot, compare the actual arc voltage with the set arc voltage, and send the comparison result to the offset controller;

[0011] The offset controller is communicatively connected to the collaborative robot, and is used to: send a first trajectory offset instruction to the collaborative robot based on the swing parameter to control the welding gun of the collaborative robot to perform arc swing; and send a second trajectory offset instruction to the collaborative robot based on the comparison result to dynamically adjust the welding gun position to achieve arc voltage tracking.

[0012] Optionally, the collaborative robot includes:

[0013] an arc swing module, configured to control the welding gun to shift in the x-axis direction of the offset coordinate system based on the first trajectory offset instruction;

[0014] an arc voltage tracking module, configured to control the welding gun to shift in the z-axis direction of the offset coordinate system based on the second trajectory offset instruction;

[0015] The offset coordinate system uses the current motion direction as the positive direction of the y-axis, the positive direction of the z-axis of the current tool coordinate system as the positive direction of the z-axis, and determines the positive direction of the x-axis using the right-hand rule.

[0016] Optionally, the swing parameters include:

[0017] Swing width and one-way swing time.

[0018] Optionally, sending a first trajectory offset instruction to the collaborative robot based on the swing parameter to control the welding gun of the collaborative robot to perform arc swing includes:

[0019] The offset value of the welding gun is gradually increased from 0 to a positive swing width value according to a single swing time, and then gradually decreased to 0; then the offset is reversed, and then the offset value is gradually decreased from 0 to a negative swing width value according to a single swing time, and then gradually increased to 0;

[0020] The above process is executed cyclically to control the welding gun to perform arc swing in the x-axis direction of the offset coordinate system.

[0021] Optionally, sending a second trajectory offset instruction to the collaborative robot based on the comparison result to dynamically adjust the welding gun position to achieve arc voltage tracking includes:

[0022] If the actual arc voltage is greater than the set arc voltage, controlling the welding gun of the collaborative robot to shift in the z-axis direction of the offset coordinate system, so that the welding gun shifts in the direction of the welding track until the actual arc voltage is equal to the set arc voltage;

[0023] If the actual arc voltage is less than the set arc voltage, the welding gun of the collaborative robot is controlled to offset in the z-axis direction of the offset coordinate system, so that the welding gun is offset in the opposite direction of the welding trajectory until the actual arc voltage is equal to the set arc voltage.

[0024] In a second aspect, the present invention provides a welding arc voltage tracking and arc swing control method based on a collaborative robot, comprising:

[0025] The collaborative robot's swing parameters and arc voltage are set through the collaborative controller based on the welding task and welding process requirements;

[0026] The collaborative robot generates a welding motion trajectory based on the welding task and welding process requirements;

[0027] The collaborative controller controls the collaborative robot to start, and the collaborative robot performs the welding task based on the welding motion trajectory;

[0028] The collaborative controller sends the swing parameter to the offset controller, and the offset controller sends a first trajectory offset instruction to the collaborative robot based on the swing parameter to control the welding gun of the collaborative robot to perform arc swing;

[0029] The actual arc voltage of the collaborative robot is collected, and the actual arc voltage is compared with the set arc voltage, and the comparison result is sent to the offset controller. The offset controller sends a second trajectory offset instruction to the collaborative robot based on the comparison result to dynamically adjust the welding gun position to achieve arc voltage tracking.

[0030] Optionally, it also includes:

[0031] The arc swing module of the collaborative robot controls the welding gun to shift in the x-axis direction of the offset coordinate system based on the first trajectory offset instruction;

[0032] The arc voltage tracking module of the collaborative robot controls the welding gun to shift in the z-axis direction of the offset coordinate system based on the second trajectory offset instruction;

[0033] The offset coordinate system uses the current motion direction as the positive direction of the y-axis, the positive direction of the z-axis of the current tool coordinate system as the positive direction of the z-axis, and determines the positive direction of the x-axis using the right-hand rule.

[0034] Optionally, the swing parameters include:

[0035] Swing width and one-way swing time.

[0036] Optionally, the offset controller sends a first trajectory offset instruction to the collaborative robot to control the welding gun of the collaborative robot to perform arc swing, including:

[0037] The offset value of the welding gun is gradually increased from 0 to a positive swing width value according to a single swing time, and then gradually decreased to 0; then the offset is reversed, and then the offset value is gradually decreased from 0 to a negative swing width value according to a single swing time, and then gradually increased to 0;

[0038] The above process is executed cyclically to control the welding gun to perform arc swing in the x-axis direction of the offset coordinate system.

[0039] Optionally, sending a second trajectory offset instruction to the collaborative robot based on the comparison result to dynamically adjust the welding gun position to achieve arc voltage tracking includes:

[0040] If the actual arc voltage is greater than the set arc voltage, controlling the welding gun of the collaborative robot to shift in the z-axis direction of the offset coordinate system, so that the welding gun shifts in the direction of the welding track until the actual arc voltage is equal to the set arc voltage;

[0041] If the actual arc voltage is less than the set arc voltage, the welding gun of the collaborative robot is controlled to offset in the z-axis direction of the offset coordinate system, so that the welding gun is offset in the opposite direction of the welding trajectory until the actual arc voltage is equal to the set arc voltage.

[0042] The beneficial effects of the present invention are: the present invention sets the swing parameters and arc voltage of the collaborative robot according to the welding task and welding process requirements through the collaborative controller, sends the swing parameters to the offset controller and then controls the collaborative robot to perform arc swing; compares the actual arc voltage of the collaborative robot with the set arc voltage, and sends the comparison result to the offset controller to dynamically adjust the welding gun position of the collaborative robot to achieve arc voltage tracking; the present invention uses the collaborative robot to achieve arc swing and arc voltage tracking during the welding process, which greatly reduces the use cost of the robot in the project, optimizes the input-output ratio of the robot in welding applications, and makes it easy for cost-sensitive small and medium-sized projects to adopt it; at the same time, it gives full play to the flexibility of the robot and significantly improves the welding efficiency. With advanced collaborative control technology, the robot can respond quickly and accurately to different welding task requirements, reduce welding time and auxiliary time, and improve production efficiency; in addition, the present invention also greatly reduces the labor intensity of the operator, and uses automated welding processes and intelligent control means to reduce manual intervention links, reduce the physical and energy consumption of workers during the welding process, and create a safer and more comfortable working environment.

[0043] The system of the present invention has other features and advantages that will be apparent from or will be described in detail in the accompanying drawings and subsequent detailed description incorporated herein, which together serve to explain the specific principles of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The above and other objects, features and advantages of the present invention will become more apparent through a more detailed description of exemplary embodiments of the present invention with reference to the accompanying drawings, in which like reference numerals generally represent like components.

[0045] Figure 1 A schematic diagram of a welding arc voltage tracking and arc swing control system based on a collaborative robot according to embodiment 1 of the present invention is shown.

[0046] Figure 2 A connection diagram of a welding arc voltage tracking and arc swing control system based on a collaborative robot according to embodiment 1 of the present invention is shown.

[0047] Figure 3 A schematic diagram of the trajectory program of the Jaka collaborative robot according to embodiment 1 of the present invention is shown.

[0048] Figure 4 A schematic diagram showing a trajectory command sent by a PLC to a Jaka collaborative robot according to embodiment 1 of the present invention is shown.

[0049] Figure 5 A flowchart showing the steps of a welding arc voltage tracking and arc swing control method based on a collaborative robot according to embodiment 2 of the present invention is shown.

[0050] Figure 6 A flow chart of welding arc voltage tracking and arc swing control according to embodiment 2 of the present invention is shown. DETAILED DESCRIPTION

[0051] The present invention will now be described in more detail with reference to the accompanying drawings. While preferred embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention may be implemented in various forms and is not limited to the embodiments set forth herein. Rather, these embodiments are provided to make the present invention more thorough and complete and to fully convey the scope of the present invention to those skilled in the art.

[0052] Example 1

[0053] like Figure 1 As shown, this embodiment provides a welding arc voltage tracking and arc swing control system based on a collaborative robot, including a collaborative robot, a collaborative controller and an offset controller;

[0054] A collaborative robot is used to generate a welding motion trajectory based on the welding task and welding process requirements, and perform the welding task based on the welding motion trajectory; the collaborative robot includes: an arc swing module, used to control the welding gun to offset in the x-axis direction of the offset coordinate system based on the first trajectory offset instruction; an arc voltage tracking module, used to control the welding gun to offset in the z-axis direction of the offset coordinate system based on the second trajectory offset instruction; the offset coordinate system takes the current motion direction as the positive direction of the y-axis, takes the positive direction of the z-axis of the current tool coordinate system as the positive direction of the z-axis, and determines the positive direction of the x-axis using the right-hand rule.

[0055] The collaborative controller is respectively connected to the offset controller and the collaborative robot for communication. The collaborative controller is used to control the collaborative robot to start / stop performing welding tasks according to the welding motion trajectory; set the swing parameters and arc voltage of the collaborative robot based on the welding task and welding process requirements, and send the swing parameters to the offset controller; and collect the actual arc voltage of the collaborative robot, and compare the actual arc voltage with the arc voltage, and send the comparison result to the offset controller; the swing parameters include: swing width and one-way swing time.

[0056] An offset controller is communicatively connected to the collaborative robot. The offset controller is configured to send a first trajectory offset instruction to the collaborative robot based on the swing parameter to control the collaborative robot's welding gun to perform arc swinging. Based on the comparison result, a second trajectory offset instruction is sent to the collaborative robot to dynamically adjust the welding gun position to achieve arc voltage tracking. Sending the first trajectory offset instruction to the collaborative robot based on the swing parameter to control the collaborative robot's welding gun to perform arc swinging includes: gradually increasing the offset value of the welding gun from 0 to a positive swing width value according to a single-pass swing time, and then gradually decreasing it to 0; then performing a reverse offset, and then gradually decreasing the offset value from 0 to a negative swing width value according to the single-pass swing time, and then gradually increasing it to 0; and repeating the above process to control the welding gun to perform arc swinging in the x-axis direction of the offset coordinate system. Based on the comparison result, a second trajectory offset instruction is sent to the collaborative robot to dynamically adjust the welding gun position to achieve arc voltage tracking, including: if the actual arc voltage is greater than the set arc voltage, the welding gun of the collaborative robot is controlled to offset in the z-axis direction of the offset coordinate system, so that the welding gun is offset in the direction of the welding trajectory until the actual arc voltage is equal to the set arc voltage; if the actual arc voltage is less than the set arc voltage, the welding gun of the collaborative robot is controlled to offset in the z-axis direction of the offset coordinate system, so that the welding gun is offset in the opposite direction of the welding trajectory until the actual arc voltage is equal to the set arc voltage.

[0057] Specifically, if Figure 2 As shown in FIG, the collaborative robot of this embodiment adopts a Jaka collaborative robot, the collaborative controller adopts a DT controller, and the offset controller adopts a PLC (programmable logic controller); the DT controller connects to the port 10001 of the Jaka collaborative robot by means of the TCP communication mechanism to establish a data interaction link with the collaborative robot; at the same time, the PLC also connects to the welding port 20045 of the Jaka collaborative robot by means of TCP. The Jaka collaborative robot is mainly responsible for writing trajectory programs, generating motion trajectories, and executing corresponding trajectory programs. The trajectory program is as follows: Figure 3 As shown, the Jaka collaborative robot is capable of real-time adjustment of x and z offsets during trajectory motion. This technical feature provides technical support for implementing arc voltage tracking and arc oscillation in TIG welding. Trajectory planning programming precisely sets the Jaka collaborative robot's motion path, speed, posture, and other parameters based on the TIG welding process requirements and welding task, ensuring the robot completes the welding task according to the predetermined trajectory.

[0058] During the Jaka collaborative robot's trajectory execution, the PLC is responsible for sending the Jaka collaborative robot supported trajectory deviation instructions. To implement the arc swing function, the PLC receives parameters such as the swing width and one-way swing time from the DT controller, and writes and sends the Jaka collaborative robot a trajectory deviation instruction similar to the following figure based on the TCP protocol supported by the Jaka collaborative robot:

[0059]

[0060] Taking the current movement direction of the welding gun as the positive direction of the y-axis, the positive direction of the z-axis of the current tool coordinate system as the positive direction of the z-axis, and the right-hand rule to determine the positive direction of the x-axis, the following control is achieved in the x-axis direction (where the values ​​in the y and z directions are set to zero): the offset value is gradually increased from 0 to the positive swing width value according to the one-way swing time, and then gradually decreased to 0; then the offset is reversed, and the offset is gradually reduced from 0 to the negative swing width value according to the one-way swing time, and then gradually increased to 0. By cyclically executing this process, the Jaka collaborative robot can realize the arc swing function in the x-direction during trajectory execution, where the one-way swing time refers to the time required for the welding gun to complete the entire swing width. Using the single-stroke swing time, swing width, and the system's default offset increment (e.g., 1 mm), we can calculate the interval for sending the first trajectory offset command. This interval is called the offset command transmission cycle. The welding gun's swing process involves sending the first trajectory offset command over multiple offset command transmission cycles within the single-stroke swing time, gradually increasing the welding gun's offset value from 0 to the positive swing width, then gradually decreasing it to 0, and then shifting in the opposite direction. Within the single-stroke swing time, we then send the first trajectory offset command over multiple offset command transmission cycles, gradually decreasing it from 0 to the negative swing width, and then gradually increasing it back to 0. For example, if the single-stroke swing time is 200 milliseconds, the swing width is 10 mm, and the system default offset increment is 1 mm, we can calculate that the first trajectory offset command needs to be sent every 20 milliseconds, meaning the offset command transmission cycle is 20 milliseconds. The first time the first trajectory offset command is sent, the offset is 1 mm. After the second time the command is sent, the offset increases from 1 mm to 2 mm, and so on until, after the tenth time, the offset reaches 10 mm in the x-direction of the offset coordinate system. Next, the offset value in the x-direction of the offset instruction is successively reduced from 10 mm, 9 mm, to 0; then the offset is reversed, and after multiple offset instruction sending cycles, the offset is gradually reduced from 0 to the negative swing width value, and then gradually increased to 0, and this process is executed in a loop.

[0061] To implement the arc voltage tracking function, during the Jaka collaborative robot's trajectory operation, the PLC will receive notifications of positive or negative deviations in the z direction from the DT controller, and write and send trajectory deviation instructions similar to the following to the Jaka collaborative robot based on the TCP protocol supported by the Jaka collaborative robot:

[0062]

[0063] By gradually increasing or decreasing the offset value in the z direction (where the values ​​in the x and y directions are set to zero), the welding gun can be raised or lowered, thereby increasing or decreasing the arc voltage. Through this closed-loop control process, the system can dynamically adjust the welding gun position to accurately achieve arc voltage tracking. Figure 4 shown.

[0064] The DT controller's core function is to coordinate the operation of the Jaka collaborative robot and the PLC. The DT controller stores various welding parameters, including the arc swing width and speed for the arc swing function, and the arc voltage tracking function for the arc voltage tracking function. Communication between the DT controller and the PLC occurs via the Modbus protocol over TCP. This protocol choice leverages the versatility and stability of the Modbus protocol in industrial control and the reliable data transmission characteristics of the TCP protocol. This ensures efficient and accurate exchange of control information and status data between the DT controller and the PLC, thereby ensuring the interoperability and stability of the entire system during TIG welding operations. The DT controller connects to the Jaka collaborative robot's port 10001 and sends various control commands to it, enabling precise control of the start and stop of the welding process. The DT controller connects to the PLC via TCP and the Modbus protocol to transmit required parameters and control commands. The PLC also connects to the collaborative robot's welding port 20045 via TCP to control trajectory deviation during operation. This communication method based on the TCP protocol is efficient and stable, ensuring accurate transmission of instructions and timely response, providing a solid guarantee for precise TIG welding process control.

[0065] The DT controller can start and stop the trajectory program on the Jaka cobot. After starting the trajectory program on the robot, the DT controller simultaneously starts the welding process. During welding, when the arc oscillation function is enabled, the DT controller sends parameters such as the oscillation width to the PLC. Based on the robot's supported command protocol, the PLC sends a first trajectory offset command in the x-direction to the Jaka cobot, enabling arc oscillation. When the arc voltage tracking function is enabled, the DT controller collects the arc voltage during welding in real time and compares it with the tracking arc voltage set in the system settings. If the collected voltage exceeds the target value, the DT controller notifies the PLC to send a second trajectory offset command in the z-direction to the Jaka cobot, shifting it toward the welding trajectory and lowering the welding gun, thereby reducing the arc voltage. If the collected voltage falls below the target value, the DT controller notifies the PLC to send a second trajectory offset command in the z-direction to the Jaka cobot, shifting it away from the welding trajectory and raising the welding gun, thereby increasing the arc voltage. Through this closed-loop control mechanism, the system can dynamically adjust the welding gun position for precise arc voltage tracking. Through the coordination of the DT controller, the Jaka collaborative robot and PLC can work closely together to achieve the arc voltage tracking and arc swing functions required in the TIG welding process, effectively improving welding quality and efficiency.

[0066] This embodiment can bring significant benefits to small and medium-sized projects that use TIG welding technology. On the one hand, it greatly reduces the cost of using robots in the project. Through innovative technical architecture and resource integration, the input-output ratio of robots in TIG welding applications is optimized, so that cost-sensitive small and medium-sized projects can also be easily adopted. On the other hand, the flexibility of the Jaka collaborative robot is fully utilized to significantly improve the efficiency of TIG welding. With advanced collaborative control technology, the Jaka collaborative robot can respond quickly and accurately to the requirements of different welding tasks, reduce welding time and auxiliary time, and improve production efficiency. In addition, this technology also greatly reduces the labor intensity of the operator. With the help of automated welding processes and intelligent control methods, it reduces manual intervention links, reduces the physical and mental consumption of workers during the welding process, and creates a safer and more comfortable working environment.

[0067] Example 2

[0068] like Figure 5 and Figure 6 As shown, this embodiment provides a welding arc voltage tracking and arc swing control method based on a collaborative robot. Based on the welding arc voltage tracking and arc swing control system based on the collaborative robot described in Example 1, the method includes:

[0069] Based on the welding task and welding process requirements, the DT controller sets the Jaka collaborative robot's swing parameters and arc voltage and sends them to the PLC;

[0070] The Jaka collaborative robot generates welding motion trajectories based on welding tasks and welding process requirements;

[0071] The DT controller starts the Jaka collaborative robot, which then performs welding tasks based on the welding motion trajectory.

[0072] The DT controller sends the swing parameters to the PLC. Based on the swing parameters, the PLC sends a first trajectory offset instruction to the Jaka collaborative robot to control the welding gun of the Jaka collaborative robot to perform arc swing.

[0073] The DT controller collects the actual arc voltage of the Jaka collaborative robot, compares the actual arc voltage with the arc voltage, and sends the comparison result to the PLC. Based on the comparison result, the PLC sends a second trajectory offset instruction to the Jaka collaborative robot to dynamically adjust the welding gun position to achieve arc voltage tracking.

[0074] In this embodiment, it also includes:

[0075] The arc swing module of the Jaka collaborative robot controls the welding gun to shift in the x-axis direction of the offset coordinate system based on the first trajectory offset instruction;

[0076] The arc voltage tracking module of the Jaka collaborative robot controls the welding gun to shift in the z-axis direction of the offset coordinate system based on the second trajectory offset instruction;

[0077] The offset coordinate system takes the current movement direction of the welding gun as the positive direction of the y-axis, the positive direction of the z-axis of the current tool coordinate system as the positive direction of the z-axis, and the positive direction of the x-axis is determined by the right-hand rule.

[0078] In this embodiment, the swing parameters include:

[0079] Swing width and one-way swing time.

[0080] In this embodiment, the PLC sends a first trajectory offset instruction to the Jaka collaborative robot to control the welding gun of the Jaka collaborative robot to perform arc swing, including:

[0081] According to the single-stroke swing time, the offset value of the welding gun is gradually increased from 0 to the positive swing width value, and then gradually decreased to 0; then the offset is reversed, and then according to the single-stroke swing time, the offset value is gradually decreased from 0 to the negative swing width value, and then gradually increased to 0;

[0082] The above process is executed cyclically to control the welding gun to swing the arc in the x-axis direction of the offset coordinate system.

[0083] In this embodiment, the PLC sends a second trajectory offset instruction to the Jaka collaborative robot based on the comparison result to dynamically adjust the welding gun position to achieve arc voltage tracking, including:

[0084] If the actual arc voltage is greater than the set arc voltage, the welding gun of the Jaka collaborative robot is controlled to shift in the z-axis direction of the offset coordinate system, so that the welding gun shifts in the direction of the welding track until the actual arc voltage is equal to the set arc voltage;

[0085] If the actual arc voltage is less than the set arc voltage, the welding gun of the Jaka collaborative robot is controlled to shift in the z-axis direction of the offset coordinate system, so that the welding gun shifts in the opposite direction of the welding trajectory until the actual arc voltage is equal to the set arc voltage.

[0086] While various embodiments of the present invention have been described above, the above description is intended to be illustrative, not exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A welding arc voltage tracking and arc swing control system based on a collaborative robot, characterized in that: Includes collaborative robots, collaborative controllers, and offset controllers; The collaborative robot is used to generate a welding motion trajectory based on the welding task and welding process requirements, and perform the welding task based on the welding motion trajectory; The collaborative controller is communicatively connected to the offset controller and the collaborative robot, respectively, and is used to: control the collaborative robot to start / stop performing the welding task according to the welding motion trajectory; set the swing parameters and arc voltage of the collaborative robot based on the welding task and welding process requirements, and send the swing parameters to the offset controller; and collecting an actual arc voltage of the collaborative robot, comparing the actual arc voltage with a set arc voltage, and sending the comparison result to the offset controller; The offset controller is in communication with the collaborative robot, and is configured to: send a first trajectory offset instruction to the collaborative robot based on the swing parameter to control the welding gun of the collaborative robot to perform arc swing; and send a second trajectory offset instruction to the collaborative robot based on the comparison result to dynamically adjust the position of the welding gun to achieve arc voltage tracking; The collaborative robot comprises: an arc swing module, configured to control the welding gun to shift in the x-axis direction of the offset coordinate system based on the first trajectory offset instruction; an arc voltage tracking module, configured to control the welding gun to shift in the z-axis direction of the offset coordinate system based on the second trajectory offset instruction; The offset coordinate system uses the current motion direction as the positive direction of the y-axis, the positive direction of the z-axis of the current tool coordinate system as the positive direction of the z-axis, and determines the positive direction of the x-axis using the right-hand rule.

2. The welding arc voltage tracking and arc swing control system based on a collaborative robot according to claim 1, characterized in that: The swing parameters include: Swing width and one-way swing time.

3. The welding arc voltage tracking and arc swing control system based on a collaborative robot according to claim 2, characterized in that: Sending a first trajectory offset instruction to the collaborative robot based on the swing parameter to control the welding gun of the collaborative robot to perform arc swing includes: The offset value of the welding gun is gradually increased from 0 to a positive swing width value according to a single swing time, and then gradually decreased to 0; then the offset is reversed, and then the offset value is gradually decreased from 0 to a negative swing width value according to a single swing time, and then gradually increased to 0; The above process is executed cyclically to control the welding gun to perform arc swing in the x-axis direction of the offset coordinate system.

4. The welding arc voltage tracking and arc swing control system based on a collaborative robot according to claim 2, characterized in that: The sending a second trajectory offset instruction to the collaborative robot based on the comparison result to dynamically adjust the welding gun position to achieve arc voltage tracking includes: If the actual arc voltage is greater than the set arc voltage, controlling the welding gun of the collaborative robot to shift in the z-axis direction of the offset coordinate system, so that the welding gun shifts in the direction of the welding track until the actual arc voltage is equal to the set arc voltage; If the actual arc voltage is less than the set arc voltage, the welding gun of the collaborative robot is controlled to offset in the z-axis direction of the offset coordinate system, so that the welding gun is offset in the opposite direction of the welding trajectory until the actual arc voltage is equal to the set arc voltage.

5. A welding arc voltage tracking and arc swing control method based on a collaborative robot, characterized in that: The welding arc voltage tracking and arc swing control system based on a collaborative robot according to any one of claims 1 to 4 is adopted, and the method comprises: The collaborative robot's swing parameters and arc voltage are set through the collaborative controller based on the welding task and welding process requirements; The collaborative robot generates a welding motion trajectory based on the welding task and welding process requirements; The collaborative controller controls the collaborative robot to start, and the collaborative robot performs the welding task based on the welding motion trajectory; The collaborative controller sends the swing parameter to the offset controller, and the offset controller sends a first trajectory offset instruction to the collaborative robot based on the swing parameter to control the welding gun of the collaborative robot to perform arc swing; collecting an actual arc voltage of the collaborative robot, comparing the actual arc voltage with a set arc voltage, and sending the comparison result to the offset controller, wherein the offset controller sends a second trajectory offset instruction to the collaborative robot based on the comparison result to dynamically adjust the welding gun position to achieve arc voltage tracking; The arc swing module of the collaborative robot controls the welding gun to shift in the x-axis direction of the offset coordinate system based on the first trajectory offset instruction; The arc voltage tracking module of the collaborative robot controls the welding gun to shift in the z-axis direction of the offset coordinate system based on the second trajectory offset instruction; The offset coordinate system uses the current movement direction of the welding gun as the positive direction of the y-axis, the positive direction of the z-axis of the current tool coordinate system as the positive direction of the z-axis, and determines the positive direction of the x-axis using the right-hand rule.

6. The welding arc voltage tracking and arc swing control method based on a collaborative robot according to claim 5, characterized in that: The swing parameters include: Swing width and one-way swing time.

7. The welding arc voltage tracking and arc swing control method based on a collaborative robot according to claim 6, characterized in that: The swing parameter sends a first trajectory offset instruction to the collaborative robot to control the welding gun of the collaborative robot to perform arc swing, including: The offset value of the welding gun is gradually increased from 0 to a positive swing width value according to a single swing time, and then gradually decreased to 0; then the offset is reversed, and then the offset value is gradually decreased from 0 to a negative swing width value according to a single swing time, and then gradually increased to 0; The above process is executed cyclically to control the welding gun to perform arc swing in the x-axis direction of the offset coordinate system.

8. The welding arc voltage tracking and arc swing control method based on a collaborative robot according to claim 6, characterized in that: The sending a second trajectory offset instruction to the collaborative robot based on the comparison result to dynamically adjust the welding gun position to achieve arc voltage tracking includes: If the actual arc voltage is greater than the set arc voltage, controlling the welding gun of the collaborative robot to shift in the z-axis direction of the offset coordinate system, so that the welding gun shifts in the direction of the welding track until the actual arc voltage is equal to the set arc voltage; If the actual arc voltage is less than the set arc voltage, the welding gun of the collaborative robot is controlled to offset in the z-axis direction of the offset coordinate system, so that the welding gun is offset in the opposite direction of the welding trajectory until the actual arc voltage is equal to the set arc voltage.

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