Multi-degree-of-freedom welding workstation based on compensation type nine-axis double robots

Abstract

The invention discloses a multi-degree-of-freedom welding workstation based on compensation type nine-axis double robots, and relates to the technical field of welding, the multi-degree-of-freedom welding workstation comprises a welding platform, a control system and a human-computer interaction interface, the welding platform adopts a mode of cooperative work of a compensation axis and a nine-axis mechanical arm for welding, and the control system is connected with the control system; the control system uses the industrial Ethernet to achieve collaborative operation with the welding platform and control the motion path, speed and welding parameters of the nine-axis mechanical arm, and the man-machine interaction interface is used for visually displaying the working state, the welding parameters and sensor data of the welding platform. A sensor redundancy design is adopted, a plurality of sensors which are of the same type and have complementary functions are installed at different positions of the compensation shaft and the nine-shaft mechanical arm, when one sensor breaks down, other backup sensors can still operate normally, and the situation that accurate feedback information cannot be obtained due to sensor faults is avoided; and the continuity of welding work is improved to a certain extent.

Description

Technical Field

[0001] The present invention relates to the field of welding technology, in particular to a multi-freedom welding workstation based on a compensated nine-axis dual robot. Background Art

[0002] Welding workstations are usually composed of robots with multiple degrees of freedom joints, which can flexibly move the welding gun to the desired position. They are high-end welding devices that integrate advanced mechanical structure, intelligent control and precise sensor technology. They are widely used in the aerospace field, automobile manufacturing industry and high-end equipment manufacturing. Existing multi-degree-of-freedom welding workstations lack sensor redundancy design. When a detection sensor fails, it will be difficult to accurately locate the weld position, seriously affecting the welding accuracy.

[0003] The defects of existing welding workstations are:

[0004] 1. Patent document CN217913596U discloses a dual-robot welding system, which focuses on improving welding efficiency and expanding the application range of welding, but does not consider how to ensure that when one sensor fails, it can still accurately obtain weld information and improve the continuity of welding work;

[0005] 2. Patent document CN117884818B discloses a welding robot with precise positioning capabilities. The focus is on dynamically adjusting welding parameters to improve welding quality, adapt to different welding tasks and materials, and increase production efficiency. However, the focus is on timely detecting faults and ensuring that the two robots weld along a consistent path to ensure normal welding.

[0006] 3. Patent document CN112264741B discloses a nine-axis articulated robot all-position welding system. The system primarily focuses on expanding the robot's range of motion to facilitate welding of tubular workpieces, but does not consider how to promptly remove contaminants adhering to the visual sensor to improve the accuracy of the welding process.

[0007] 4. Patent document CN212122162U discloses a multi-degree-of-freedom welding robot, which mainly considers how to realize multi-degree-of-freedom welding and ensure the stability of welding, thereby increasing the scope of use of welding operations, but does not consider how to achieve self-lubrication and extend the service life of the compensation shaft. Summary of the Invention

[0008] The object of the present invention is to provide a multi-degree-of-freedom welding workstation based on a compensated nine-axis dual robot to solve the problems raised in the above background technology.

[0009] To achieve the above objectives, the present invention provides the following technical solutions: a multi-degree-of-freedom welding workstation based on a compensated nine-axis dual robot, comprising a welding platform, a control system, and a human-machine interface. The welding platform utilizes a compensated axis and a nine-axis robotic arm to work together for welding. The control system uses industrial Ethernet to achieve collaborative operation with the welding platform, controlling the motion path, speed, and welding parameters of the nine-axis robotic arm. The human-machine interface is used to intuitively display the working status, welding parameters, and sensor data of the welding platform. The human-machine interface is a touch screen display and a computer interface.

[0010] Two groups of visual sensors 2 are provided on the outer wall of one side of the compensation shaft, a nine-axis robotic arm is provided on the top of the compensation shaft through bolts, and two groups of scrapers are embedded in the joints of the nine-axis robotic arm, and two groups of connecting parts are provided at the output end of the nine-axis robotic arm, and an end effector is movably provided between the two groups of connecting parts, and force sensors are evenly arranged on the outer surface of the end effector, and the force sensors are used to monitor the force of the welding process in real time; contact sensors and visual sensors 3 are evenly arranged on the bottom of the connecting parts, and visual sensors 3 are staggered with the contact sensors; a bottom plate is provided at the bottom of the compensation shaft, and a tooling fixture and a fixed bracket are provided on the top of the bottom plate, and the tooling fixture is located between the compensation shaft and the fixed bracket; a workpiece to be welded is provided on the top of the tooling fixture, and a visual sensor 1 is provided at one end of the fixed bracket, and the visual sensor 1 is used to monitor the entire welding area; proximity sensors are evenly arranged at the joints of the output end of the nine-axis robotic arm.

[0011] Preferably, the control system includes a main controller, data reception and storage, data analysis, fault diagnosis and collision risk assessment. The data reception and storage is used to receive and store real-time data collected by the sensor. The data analysis is responsible for analyzing the received data and analyzing the data fluctuations. The fault diagnosis combines the results of the data analysis to determine the fault type and location of the sensor and compensator, and feeds back the diagnosis results to the main controller. The collision risk assessment combines the sensor and the robot kinematic model to determine whether there is a collision risk between the two nine-axis robotic arms. The main controller is used to determine the current operating mode of the welding platform according to the fault situation, and decide whether to trigger emergency braking according to the evaluation results.

[0012] Preferably, a placement groove and a scraper are provided on the front side of the compensation shaft and the joint of the nine-axis robotic arm. The scraper is located between the placement groove and the visual sensor 2. An electric push rod 1 is provided inside the placement groove, and an electric push rod 2 is provided at the output end of the electric push rod 1. A cleaning brush 1 is provided at the output end of the electric push rod 2, and the cleaning brush 1 is used to clean dust on the visual sensor 2.

[0013] Preferably, a control drive and a guide rod are provided inside the compensation shaft, the guide rod is located on one side of the control drive, a screw rod is provided at the output end of the control drive, a slider is sleeved on the outer surfaces of the screw rod and the guide rod, a self-lubricating component is provided inside the slider, and the self-lubricating component is used to regularly lubricate the guide rod and the screw rod.

[0014] Preferably, the self-lubricating component includes an oil storage tank provided in the slider, two groups of oil guide channels are provided at the bottom of the oil storage tank, two groups of receiving grooves are provided inside the slider, and the two groups of receiving grooves are respectively located on the outside of the screw rod and the guide rod, and two groups of small controllable push rods three are provided inside the slider, and a sponge brush is provided at the output end of the small controllable push rod three, and the sponge brush is located inside the receiving groove.

[0015] Preferably, a base is provided on the top of the slider, the base is located above the compensation shaft, the top of the base is in contact with the bottom of the nine-axis robotic arm, an oil pipe is opened inside the base, one end of the oil pipe is connected to the top of the oil storage tank.

[0016] Preferably, a small controllable push rod 1 is embedded in the outer wall of one side of the slider, a small controllable push rod 2 is provided at the output end of the small controllable push rod 1, a cleaning brush 2 is provided at the output end of the small controllable push rod 2, and the cleaning brush 2 is located above the screw rod. Two sets of position detection devices are provided at the bottom of the slider, and the position detection devices are used to monitor the position and movement status of the slider and the nine-axis robotic arm in real time.

[0017] Preferably, a slide groove is provided on the top of the compensation shaft, and the slide groove is located on the outside of the slider. Two sets of folding protections are provided in the slide groove, and one end of the two sets of folding protections are respectively connected to the outer surfaces of both sides of the slider.

[0018] Preferably, the fault diagnosis includes sensor diagnosis, compensator diagnosis and alarm modules. The compensator diagnosis determines whether the coordination performance of the compensator is faulty through the motion accuracy and response speed of the compensator. The alarm module includes fault classification alarm and alarm information recording and tracing. The fault classification alarm sends different alarm signals according to different types of faults. The alarm information recording and tracing is responsible for recording the information of each alarm in the system log and generating a report.

[0019] Preferably, the sensor diagnosis includes vision sensor diagnosis, force sensor diagnosis, contact sensor diagnosis, proximity sensor diagnosis and position sensor diagnosis.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The present invention adopts a sensor redundancy design, and installs multiple sensors of the same type and with complementary functions at different positions on the compensation axis and the nine-axis robot arm to obtain weld information from multiple angles. When one sensor fails, the other backup sensors can still operate normally, and a contact sensor is used to assist the visual sensor in detecting the weld position. The visual sensor focuses on identifying and locating welds that are far away and large in area, while the contact sensor focuses on close-range, high-precision weld tracking. The two cooperate with each other. Even if a sensor at the same position fails, the other sensor at the same position can still maintain operation to a certain extent, so as to avoid the situation where accurate feedback information cannot be obtained due to sensor failure, which leads to welding out of control, thereby improving the continuity of welding work to a certain extent.

[0022] 2. The present invention establishes sensor fault diagnosis by monitoring the data fluctuations and communication status of the sensor in real time. According to the data fluctuations and communication status of the sensor, the fault is discovered in time, the type and location of the sensor fault is accurately determined, and an alarm is issued to prompt the operator to repair the sensor as soon as possible. At the same time, the robot is automatically switched to a safe mode. By using the detection data of other sensors and the previously stored weld position information and the motion trajectory records of the robot, an open-loop control method is adopted to allow the dual robots to continue welding operations according to the known correct path, so as to avoid the accurate implementation of the entire welding process being affected by the malfunction of individual sensors. Faults can be discovered in time to ensure the normal progress of welding.

[0023] 3. The present invention regularly cleans the head of the visual sensor to remove a large amount of spatter, dust, smoke and other pollutants attached to the surface of the visual sensor at various positions, thereby improving the accuracy of the welding process and increasing the accuracy of collision risk assessment.

[0024] 4. The present invention automatically lubricates the compensation shaft regularly. The small controllable push rod is extended three times to push the sponge brush toward the screw rod and the guide rod. The lubricating oil adsorbed on the sponge brush will be adsorbed on the surface of the screw rod and the guide rod under the squeezing action of the sponge brush, the screw rod and the guide rod, so as to prevent the compensation shaft from mechanical wear due to long-term work, which will lead to a decrease in the movement accuracy of the compensation shaft and affect the compensation effect.

[0025] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention;

[0026] Figure 2 Schematic diagram of the side perspective structure of the nine-axis robotic arm of the present invention;

[0027] Figure 3 Schematic diagram of the cross-sectional structure of the nine-axis robotic arm of the present invention;

[0028] Figure 42 is another cross-sectional structural diagram of the nine-axis robotic arm of the present invention;

[0029] Figure 5 Schematic diagram of the cross-sectional structure of the compensation shaft of the present invention;

[0030] Figure 6 Schematic diagram of the side cross-sectional structure of the compensation shaft of the present invention;

[0031] Figure 7 For the present invention Figure 6 Schematic diagram of the structure of A;

[0032] Figure 8 is a system diagram of the present invention;

[0033] Figure 9 It is a structural diagram of the control system of the present invention;

[0034] Figure 10 This is a structural diagram of the sensor diagnosis structure of the present invention.

[0035] In the figure: 1. Compensation shaft; 2. Nine-axis robotic arm; 3. End effector; 4. Fixture; 5. Workpiece to be welded; 6. Bottom plate; 7. Base; 8. Folding protection; 9. Fixed bracket; 10. Vision sensor 1; 11. Vision sensor 2; 12. Placement slot; 13. Scraper; 14. Force sensor; 15. Contact sensor; 16. Vision sensor 3; 17. Sponge brush; 18. Electric push rod 1; 19. Electric push rod 2; 20. Cleaning brush 1; 21. Control driver; 22. Screw; 23. Guide rod; 24. Slider; 25. Position detection device; 26. Small controllable push rod 1; 27. Small controllable push rod 2; 28. Cleaning brush 2; 29. ​​Oil pipeline; 30. Oil storage tank; 31. Oil guide channel; 32. Small controllable push rod 3; 33. Storage slot. DETAILED DESCRIPTION

[0036] The following will provide a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0037] In the description of the present invention, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," "the other end," and the like, indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0038] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "provided with," "connected," etc., should be understood in a broad sense. For example, "connected" may refer to a fixed connection, a detachable connection, or an integral connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediate medium; or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0039] See also Figure 1 、 Figure 2 and Figure 8 The present invention provides an embodiment of a multi-degree-of-freedom welding workstation based on a compensated nine-axis dual robot, comprising a welding platform, a control system, and a human-machine interface. The welding platform uses a compensation axis 1 and a nine-axis robotic arm 2 to work together for welding. The control system uses industrial Ethernet to achieve collaborative operation with the welding platform to control the motion path, speed, and welding parameters of the nine-axis robotic arm 2. The human-machine interface is used to intuitively display the working status, welding parameters, and sensor data of the welding platform. The human-machine interface is a touch screen display and a computer interface.

[0040] Two groups of visual sensors 2 11 are provided on the outer wall of one side of the compensation shaft 1, and a nine-axis robot arm 2 is provided on the top of the compensation shaft 1 through bolts. Two groups of scrapers 13 are embedded in the joints of the nine-axis robot arm 2. The output end of the nine-axis robot arm 2 is provided with two groups of connecting parts, and an end effector 3 is movably provided between the two groups of connecting parts. Force sensors 14 are evenly arranged on the outer surface of the end effector 3. The force sensor 14 is used to monitor the force of the welding process in real time. Contact sensors 15 and visual sensors 3 16 are evenly arranged on the bottom of the connecting parts. The visual sensors 3 16 and the contact sensors 15 are staggered. A bottom plate 6 is provided at the bottom of the compensation shaft 1, and a tooling fixture 4 and a fixed bracket 9 are provided on the top of the bottom plate 6. The tooling fixture 4 is located between the compensation shaft 1 and the fixed bracket 9. A workpiece 5 to be welded is provided on the top of the tooling fixture 4. A visual sensor 10 is provided at one end of the fixed bracket 9. The visual sensor 10 is used to monitor the entire welding area. Proximity sensors are evenly arranged at the joints of the output end of the nine-axis robot arm 2.

[0041] Furthermore, the welding platform consists of two sets of compensation axes 1 and a nine-axis robot arm 2. The compensation axes 1 can work in conjunction with the nine-axis robot arm 2. During the welding process, the compensation axes 1 can be used to fine-tune the motion trajectory of the nine-axis robot arm 2, effectively correcting position deviations caused by factors such as the irregular shape of the workpiece 5 to be welded, positioning errors of the fixture 4, accumulated errors in robot motion, or thermal deformation, thereby achieving high-precision welding. The nine-axis robot arm 2 can approach the weld from multiple angles, which can meet the welding needs of workpieces with certain special structures or space restrictions. It has high flexibility and adaptability. Multiple sets of visual sensors are set on one side of the compensation axis 1 and at different joints of the nine-axis robot arm 2. Sensor 2 11, real-time monitoring is performed by visual sensor 10 just above the workpiece 5 to be welded, and multiple groups of contact sensors 15 and visual sensor 3 16 are set on the connecting piece between the nine-axis robot arm 2 and the end effector 3. Visual sensor 3 16 can obtain a clear image of the weld in real time as the nine-axis robot arm 2 moves, which is convenient for direct visual monitoring and tracking of the welding process, timely discovering the deviation of the weld and feeding it back to the control system through industrial Ethernet for adjustment. Visual sensor 10 overlooks the entire welding area from above the working area, can obtain macroscopic welding scene information, monitor multiple welding parts or the overall welding process, and simultaneously observe The overall working state of multiple welds and robots is to avoid the obstruction and collision of the visual sensor 10 during the movement of the two sets of nine-axis robotic arms 2. The visual sensor 2 11 at the joint of the nine-axis robotic arm 2 mainly obtains images at a specific angle. The visual angle is flexibly adjusted by the rotation of the joint to realize the observation of welds at different positions. The weld information at multiple angles can be obtained through the visual sensors at different positions. In addition, a redundant design is adopted to install multiple visual sensors of the same type to identify the welds, locate the distance of the welds and determine the area of ​​the welds. When a sensor fails, the other backup sensors can still operate normally. At the same time, the visual sensor is used. The contact sensors 15 of the same type and with complementary functions track the weld seam at close range and with high precision. Through the cooperation between the contact sensors 15 and the visual sensors, when one sensor at the same position fails, the other sensor at the same position can also maintain operation to a certain extent, so as to avoid the situation where accurate feedback information cannot be obtained due to sensor failure, which in turn leads to welding loss of control. This improves the continuity of the welding work to a certain extent. Similarly, multiple groups of force sensors 14 are set on the outer surface of the end effector 3 to detect the action force and reaction force during the welding process, so as to achieve precise control of the welding force and prevent the occurrence of welding deformation and defects.

[0042] The human-machine interaction interface includes a touch screen and a computer interface. Operators can program welding tasks, set parameters, monitor equipment, and diagnose faults on the interactive interface. The interactive interface adopts a graphical interface design and can display the motion status of the compensation axis 1 and the nine-axis robot arm 2, welding parameters, sensor data and other information, making it convenient for operators to understand the working status of the welding workstation in real time.

[0043] See also Figure 9 and Figure 10 , an embodiment provided by the present invention: a multi-degree-of-freedom welding workstation based on a compensated nine-axis dual robot, the control system including a main controller, data reception and storage, data analysis, fault diagnosis and collision risk assessment, the data reception and storage is used to receive and store real-time data collected by the sensor, the data analysis is responsible for analyzing the received data and analyzing the data fluctuation, the fault diagnosis combines the results of the data analysis to determine the fault type and location of the sensor and compensator, and feeds back the diagnosis results to the main controller, the collision risk assessment combines the sensor and the robot kinematic model to determine whether there is a collision risk between the two nine-axis robotic arms 2, the main controller is used to determine the current operation mode of the welding platform according to the fault situation, and decide whether to trigger the emergency brake according to the assessment result;

[0044] The fault diagnosis includes sensor diagnosis, compensator diagnosis and alarm modules. The compensator diagnosis determines whether the coordination performance of the compensator 1 is faulty based on the motion accuracy and response speed of the compensator 1. The alarm module includes fault classification alarm and alarm information recording and tracing. The fault classification alarm sends different alarm signals according to different types of faults. The alarm information recording and tracing is responsible for recording the information of each alarm in the system log and generating a report.

[0045] The sensor diagnosis includes vision sensor diagnosis, force sensor diagnosis, contact sensor diagnosis, proximity sensor diagnosis and position sensor diagnosis.

[0046] Furthermore, the real-time data detected by the sensor is transmitted to the data receiving and storage through the industrial Ethernet, and then the data analysis monitors the data fluctuations, communication status, etc. of the sensor in real time. The sensor diagnosis detects faults in time according to the data fluctuations and communication status of various sensors, accurately determines the type and location of sensor faults, and issues corresponding types of sound alarms. At the same time, the fault information is displayed in detail on the human-computer interaction interface, prompting the operator to repair the sensor as soon as possible, and automatically switches the robot to safe mode. The detection data of other sensors and the previously stored weld position information and the robot's motion trajectory record are used, and open-loop control is adopted to allow the dual robots to continue welding operations according to the known correct path, so as to avoid the accuracy of the entire welding process being affected by the inability of individual sensors to be used normally. Faults can be detected in time to ensure the normal progress of welding. At the same time, the compensator diagnosis The position detection device 25 is used to check the motion accuracy of the compensation axis 1, and record whether the time required for the compensation axis 1 to complete the compensation action from receiving the adjustment instruction to completing the compensation action meets the requirements, determine whether there is a lack of coordination, and issue a corresponding type of light alarm. At the same time, the fault information is displayed in detail on the human-computer interaction interface, and the information of each alarm, including the fault type, occurrence time, fault location, etc., is recorded in the system log. In the subsequent troubleshooting and equipment maintenance process, the fault history can be easily traced, the cause of the fault can be analyzed, and the fault pattern can be summarized to provide a basis for the optimization and improvement of the equipment. In addition, path planning is performed for the two groups of nine-axis robotic arms 2 to avoid collisions. When the proximity sensor detects that the distance is less than the safety threshold, it is combined with the current movement direction and speed of the robot to determine whether there is a collision risk. Once it is determined that there is a collision risk, emergency braking is immediately performed.

[0047] See also Figure 2 、 Figure 3 and Figure 4 , an embodiment provided by the present invention: a multi-degree-of-freedom welding workstation based on a compensating nine-axis dual robot, the front of the compensating axis 1 and the joint of the nine-axis robot arm 2 are provided with a placement groove 12 and a scraper 13, the scraper 13 is located between the placement groove 12 and the visual sensor 2 11, the interior of the placement groove 12 is provided with an electric push rod 18, the output end of the electric push rod 18 is provided with an electric push rod 2 19, the output end of the electric push rod 2 19 is provided with a cleaning brush 1 20, the cleaning brush 1 20 is used to clean dust on the visual sensor 2 11.

[0048] Furthermore, during the welding process, a large amount of pollutants such as spatter, dust and smoke will be generated, and will adhere to the surface of the visual sensor at various positions, thereby interfering with the normal monitoring of the visual sensor. In order for the visual sensor to obtain accurate information, the head of the visual sensor needs to be cleaned regularly, thereby improving the accuracy of the welding process and increasing the accuracy of the collision risk assessment. When cleaning is required, the electric push rod 18 is extended, and the electric push rod 2 19 and the cleaning brush 20 are pushed out of the placement slot 12. Then the electric push rod 2 19 is extended and the cleaning brush 20 is pushed to clean the pollutants on the head of the visual sensor 2 11. Before retracting the cleaning brush 20 into the placement slot 12, the electric push rod 2 19 is controlled to repeatedly extend and retract, so that the soft bristle part of the cleaning brush 20 scrapes back and forth on the scraper 13 to scrape off the pollutants on the cleaning brush 20 to avoid affecting the next cleaning effect.

[0049] See also Figure 5 、 Figure 6 and Figure 7 The present invention provides an embodiment of a multi-degree-of-freedom welding workstation based on a compensating nine-axis dual robot, wherein a control driver 21 and a guide rod 23 are provided inside the compensating shaft 1, and the guide rod 23 is located on one side of the control driver 21. A screw rod 22 is provided at the output end of the control driver 21, and a slider 24 is sleeved on the outer surfaces of the screw rod 22 and the guide rod 23. A self-lubricating component is provided inside the slider 24, and the self-lubricating component is used to regularly lubricate the guide rod 23 and the screw rod 22.

[0050] The self-lubricating component includes an oil storage tank 30 provided in the slider 24, and two groups of oil guide channels 31 are provided at the bottom of the oil storage tank 30. Two groups of receiving grooves 33 are provided inside the slider 24, and the two groups of receiving grooves 33 are respectively located on the outside of the screw rod 22 and the guide rod 23. Two groups of small controllable push rods 32 are provided inside the slider 24, and a sponge brush 17 is provided at the output end of the small controllable push rod 32, and the sponge brush 17 is located inside the receiving groove 33.

[0051] Furthermore, when the compensation shaft 1 works for a long time, the accuracy of the screw rod 22 will decrease, which will lead to a decrease in the movement accuracy of the compensation shaft 1. When compensation is required, the expected compensation effect cannot be achieved, which affects the compensation effect. Therefore, it is necessary to lubricate the mechanical parts of the compensation shaft 1 regularly to reduce the wear between the slider 24 and the screw rod 22, thereby extending the service life of the screw rod 22 to a certain extent and ensuring the movement accuracy of the compensation shaft 1. At the same time, when lubrication is needed, the small controllable push rod 3 32 extends to push the sponge brush 17 toward the screw rod 22 and the guide rod 23. The lubricating oil absorbed on the sponge brush 17 will be adsorbed on the surface of the screw rod 22 and the guide rod 23 under the squeezing action of the sponge brush 17, the screw rod 22 and the guide rod 23. Since the screw rod 22 and the guide rod 23 are moving relative to the slider 24, the sponge brush 17 will evenly adsorb the lubricating oil on the surface of the screw rod 22 and the guide rod 23. After one lubrication, the small controllable push rod 3 32 contracts to push the sponge brush 17 again In the newly collected receiving tank 33, the lubricating oil stored in the oil storage tank 30 will flow to the sponge brush 17 along the two oil guide channels 31 at the bottom. Since the diameter of the oil guide channel 31 is extremely small, the amount of lubricating oil flowing to the sponge brush 17 is also small. After the lubricating oil is absorbed by the sponge brush 17, it will be temporarily stored in the sponge brush 17, reducing the waste of lubricating oil. At the same time, two sets of position detection devices 25 are installed under the slider 24 to monitor the movement status of the slider 24 and the nine-axis robot arm 2 so as to promptly detect the decrease in the accuracy of the compensation shaft 1. When the accuracy decreases, an alarm will be immediately issued to prompt the operator to check, calibrate and replace the internal components of the compensation shaft 1 in time, and the control system will continue to monitor the status of the compensation shaft 1 after processing, thereby improving the stability of the welding workstation. The two sets of position detection devices 25 also adopt a redundant design to prevent one set of position detection devices 25 from failing, affecting the movement monitoring of the compensation shaft 1, and causing serious errors in the welding work.

[0052] See also Figure 1 、 Figure 5 and Figure 6 The present invention provides an embodiment of a multi-degree-of-freedom welding workstation based on a compensated nine-axis dual robot. A base 7 is provided on the top of the slider 24. The base 7 is located above the compensation shaft 1. The top of the base 7 is in contact with the bottom of the nine-axis robot arm 2. An oil pipeline 29 is provided inside the base 7. One end of the oil pipeline 29 is connected to the top of the oil storage tank 30.

[0053] A small controllable push rod 1 26 is embedded in the outer wall of one side of the slider 24. A small controllable push rod 27 is provided at the output end of the small controllable push rod 1 26. A cleaning brush 28 is provided at the output end of the small controllable push rod 27. The cleaning brush 28 is located above the screw rod 22. Two sets of position detection devices 25 are provided at the bottom of the slider 24. The position detection devices 25 are used to monitor the position and movement status of the slider 24 and the nine-axis robot arm 2 in real time.

[0054] A slide groove is provided on the top of the compensation shaft 1 and is located outside the slider 24 . Two sets of folding guards 8 are provided in the slide groove, and one end of the two sets of folding guards 8 are respectively connected to the outer surfaces of both sides of the slider 24 .

[0055] Furthermore, a base 7 is provided on the top of the slider 24, and the connection between the compensation shaft 1 and the nine-axis robot arm 2 is achieved through the base 7 and bolts, which makes it easy to remove the nine-axis robot arm 2 from the compensation shaft 1, and an oil pipe 29 is provided inside the base 7, which makes it easy for the operator to add lubricating oil directly to the oil storage tank 30 through the oil pipe 29. The compensation shaft 1 drives the screw rod 22 to rotate by controlling the driver 21, so that the slider 24 moves along the direction of the guide rod 23, thereby changing the position of the nine-axis robot arm 2 to achieve overall compensation. When the slider 24 moves, the folding protection 8 at both ends of the slider 24 will expand and contract accordingly to prevent external dust from entering from the opening above the compensation shaft 1. Long-term accumulation will cause damage to the compensation. At the same time, the cleaning brush 28 is embedded in the screw groove of the screw rod 22. The mutual movement of the cleaning brush 28 and the screw rod 22 is used to clean the pollutants attached to the surface of the screw rod 22. Through two layers of protection, the influence of pollutants on the compensation shaft 1 is further reduced, and the service life of the compensation shaft 1 is extended.

[0056] Working principle: The workpiece 5 to be welded is positioned using a fixture 4, and the operator inputs control instructions to weld the workpiece. During the welding process, multiple sets of visual sensors monitor the weld and the entire welding scene. At the same time, the head of the visual sensor is cleaned regularly. In addition, the compensation shaft is self-lubricated regularly to ensure the movement accuracy of the compensation shaft 1 and to evaluate whether a fault has occurred. Once a fault is detected, an alarm is immediately issued and the operator handles it in a timely manner.

[0057] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. A multi-degree-of-freedom welding workstation based on a compensated nine-axis dual robot, characterized by: The invention comprises a welding platform, a control system and a human-machine interaction interface, wherein the welding platform adopts a compensation axis (1) and a nine-axis robot arm (2) to work in coordination for welding, the control system uses industrial Ethernet to realize coordinated operation with the welding platform, controls the motion path, speed and welding parameters of the nine-axis robot arm (2), and the human-machine interaction interface is used to intuitively display the working status, welding parameters and sensor data of the welding platform, and the human-machine interaction interface is a touch screen and a computer interface; Two groups of visual sensors (11) are provided on the outer wall of one side of the compensation shaft (1), a nine-axis robot arm (2) is provided on the top of the compensation shaft (1) through bolts, two groups of scrapers (13) are embedded in the joints of the nine-axis robot arm (2), two groups of connectors are provided at the output end of the nine-axis robot arm (2), an end effector (3) is movably provided between the two groups of connectors, force sensors (14) are evenly arranged on the outer surface of the end effector (3), the force sensors (14) are used to monitor the force of the welding process in real time, and contact sensors (15) and visual sensors are evenly arranged on the bottom of the connector. Device three (16), visual sensor three (16) and contact sensor (15) are staggeredly distributed, a bottom plate (6) is provided at the bottom of the compensation shaft (1), a tooling fixture (4) and a fixed bracket (9) are provided on the top of the bottom plate (6), the tooling fixture (4) is located between the compensation shaft (1) and the fixed bracket (9), a workpiece to be welded (5) is provided on the top of the tooling fixture (4), one end of the fixed bracket (9) is provided with visual sensor one (10), and visual sensor one (10) is used to monitor the entire welding area, and proximity sensors are evenly arranged at the joints of the output end of the nine-axis robot arm (2).

2. The multi-degree-of-freedom welding workstation based on a compensated nine-axis dual robot according to claim 1, characterized in that: The control system includes a main controller, data receiving and storage, data analysis, fault diagnosis and collision risk assessment. The data receiving and storage is used to receive and store real-time data collected by the sensor. The data analysis is responsible for analyzing the received data and analyzing the data fluctuation. The fault diagnosis is combined with the result of the data analysis to determine the fault type and location of the sensor and the compensator, and the diagnosis result is fed back to the main controller. The collision risk assessment is combined with the sensor and the robot kinematic model to determine whether there is a collision risk between the two nine-axis robotic arms (2). The main controller is used to determine the current operation mode of the welding platform according to the fault situation and decide whether to trigger the emergency brake according to the assessment result.

3. The multi-degree-of-freedom welding workstation based on a compensated nine-axis dual robot according to claim 1, characterized in that: A placement groove (12) and a scraper (13) are provided on the front of the compensation shaft (1) and the joint of the nine-axis robot arm (2). The scraper (13) is located between the placement groove (12) and the second visual sensor (11). An electric push rod (18) is provided inside the placement groove (12). An electric push rod (19) is provided at the output end of the electric push rod (18). A cleaning brush (20) is provided at the output end of the electric push rod (19). The cleaning brush (20) is used to clean dust on the second visual sensor (11).

4. The multi-degree-of-freedom welding workstation based on a compensated nine-axis dual robot according to claim 1, characterized in that: A control driver (21) and a guide rod (23) are provided inside the compensation shaft (1), the guide rod (23) is located on one side of the control driver (21), a screw rod (22) is provided at the output end of the control driver (21), a slider (24) is sleeved on the outer surfaces of the screw rod (22) and the guide rod (23), and a self-lubricating component is provided inside the slider (24), which is used to regularly lubricate the guide rod (23) and the screw rod (22).

5. The multi-degree-of-freedom welding workstation based on a compensated nine-axis dual robot according to claim 4, characterized in that: The self-lubricating component includes an oil storage tank (30) provided in a slider (24), two groups of oil guide channels (31) are provided at the bottom of the oil storage tank (30), two groups of receiving grooves (33) are provided inside the slider (24), and the two groups of receiving grooves (33) are respectively located outside the screw rod (22) and the guide rod (23), two groups of small controllable push rods (32) are provided inside the slider (24), and a sponge brush (17) is provided at the output end of the small controllable push rod (32), and the sponge brush (17) is located inside the receiving groove (33).

6. The multi-degree-of-freedom welding workstation based on a compensated nine-axis dual robot according to claim 5, characterized in that: A base (7) is provided on the top of the slider (24), and the base (7) is located above the compensation shaft (1). The top of the base (7) is in contact with the bottom of the nine-axis robot arm (2). An oil delivery pipe (29) is provided inside the base (7), and one end of the oil delivery pipe (29) is connected to the top of the oil storage tank (30).

7. The multi-degree-of-freedom welding workstation based on a compensated nine-axis dual robot according to claim 4, characterized in that: A small controllable push rod 1 (26) is embedded in the outer wall of one side of the slider (24), and a small controllable push rod 2 (27) is provided at the output end of the small controllable push rod 1 (26), and a cleaning brush 2 (28) is provided at the output end of the small controllable push rod 2 (27). The cleaning brush 2 (28) is located above the screw rod (22). Two sets of position detection devices (25) are provided at the bottom of the slider (24), and the position detection devices (25) are used to monitor the position and movement state of the slider (24) and the nine-axis robot arm (2) in real time.

8. The multi-degree-of-freedom welding workstation based on a compensated nine-axis dual robot according to claim 4, characterized in that: A slide groove is provided on the top of the compensation shaft (1), and the slide groove is located outside the slider (24). Two sets of folding guards (8) are provided in the slide groove, and one end of the two sets of folding guards (8) is connected to the outer surfaces of both sides of the slider (24) respectively.

9. The multi-degree-of-freedom welding workstation based on a compensated nine-axis dual robot according to claim 2, characterized in that: The fault diagnosis includes sensor diagnosis, compensator diagnosis and alarm module. The compensator diagnosis determines whether the coordination performance of the compensator (1) fails by the motion accuracy and response speed of the compensator (1). The alarm module includes fault classification alarm and alarm information recording and tracing. The fault classification alarm sends different alarm signals according to different types of faults. The alarm information recording and tracing is responsible for recording the information of each alarm in the system log and generating a report.

10. The multi-degree-of-freedom welding workstation based on a compensated nine-axis dual robot according to claim 9, characterized in that: The sensor diagnosis includes vision sensor diagnosis, force sensor diagnosis, contact sensor diagnosis, proximity sensor diagnosis and position sensor diagnosis.

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