Arc welding method and system

Abstract

An arc welding method adopts an arc welding system for welding, wherein an arc voltage acquisition module in the arc welding system collects arc voltage and sends it to a welding controller, the welding controller performs LMS filtering on the arc voltage to obtain a smoothed arc voltage, and then calculates a welding gun feed distance and a welding gun feed speed according to the smoothed arc voltage and an arc pressure tracking strategy, and then sends the welding gun feed distance and the welding gun feed speed to a No. 1 robot controller, the No. 1 robot controller controls a six-axis robot to execute the calculated welding gun feed distance and welding gun feed speed, the welding controller calculates process parameters according to a smoothed temperature and the moving speeds of the welding gun and a visual sensor, a welding current, and an argon gas flow adjustment strategy, and sends the process parameters to corresponding components, thereby controlling the energy output of the welding gun at the weld, avoiding the occurrence of welding defects such as welding leakage due to excessive temperature of the welding plate itself and excessive energy output of the welding gun, thereby improving welding quality, and being a powerful supplement to TIG welding control.

Description

Technical Field

[0001] The present invention relates to the field of welding manufacturing technology, and in particular to an arc welding method and system. Background Art

[0002] In actual engineering production, when robots are used to weld complex flat plate welds, manual teaching and repeated verification are generally required. This not only reduces welding efficiency but also easily leads to weld leaks due to thermal deformation. At the same time, because the welding process uses fixed process parameters such as welding current and argon gas flow, these process parameters not only cause the temperature of the plate itself to continue to rise, which is prone to weld leaks, but also increase the deformation of the plate, which in turn leads to weld leaks and fails to meet welding quality requirements. Summary of the Invention

[0003] The technical problem solved by the present invention is to provide an arc welding method and system to solve the problems in the above-mentioned background technology.

[0004] The technical problem solved by the present invention is achieved by adopting the following technical solutions:

[0005] An arc welding method uses an arc welding system for welding, and the specific steps are as follows:

[0006] (1) In the arc welding system, the right-angle robot controls the visual sensor and the six-axis robot controls the welding gun to move to the initial point of the weld.

[0007] (2) After welding starts from the initial point of the weld, the visual sensor sends the acquired welding trajectory information to the trajectory tracking and measurement module. The welding controller transmits the welding gun spatial position and posture information sent by the No. 1 robot controller and the visual sensor position information sent by the No. 2 robot controller to the trajectory tracking and measurement module. The trajectory tracking and measurement module calculates the welding gun feed coordinates, welding gun posture, and visual sensor movement coordinates and sends them to the welding controller. The welding controller sends the welding gun feed coordinates and welding gun posture information to the No. 1 robot controller and transmits the visual sensor movement coordinate information to the No. 2 robot controller. The No. 1 robot controller controls the six-axis robot to move to the welding gun feed coordinates and adjusts the welding gun posture to the tangent direction of the weld trajectory. The No. 2 robot controller controls the movement of the visual sensor.

[0008] (3) After starting welding, the arc voltage acquisition module collects the arc voltage of the plate and sends it to the welding controller. The welding controller performs LMS filtering on the received arc voltage to obtain a smooth arc voltage, and then calculates the welding gun feed distance and welding gun feed speed based on the smooth arc voltage and arc pressure tracking strategy. The welding gun feed distance and welding gun feed speed are then sent to the No. 1 robot controller. The No. 1 robot controller controls the six-axis robot to execute the calculated welding gun feed distance and welding gun feed speed, thereby changing the distance from the welding gun to the welding plate and the moving speed of the welding gun in the vertical direction, thereby adjusting the arc voltage and arc pressure tracking speed;

[0009] (4) After welding is started, the temperature sensor sends the collected temperature to the welding controller, which then filters the collected temperature through SG filtering to obtain a smoothed temperature. The welding controller calculates the latest moving speed, welding current, and argon flow of the welding gun and visual sensor based on the smoothed temperature and the moving speed, welding current, and argon flow of the welding gun and visual sensor. The welding controller then sends the moving speed of the welding gun to the No. 1 robot controller, the moving speed of the visual sensor to the No. 2 robot controller, the welding current to the welding power supply, and the argon flow to the flow controller, thereby controlling the energy output of the welding gun at the weld.

[0010] In the present invention, the relationship between the arc voltage and the arc length (the distance from the tungsten electrode to the welding point) can be expressed as

[0011] For U h =U Z +K·L(1)

[0012] In formula (1), U h is the arc voltage, U Z It is the sum of the cathode voltage drop and the anode voltage drop under certain conditions (certain current and electrode material), K is the arc voltage gradient, which is a proportional constant, and L is the distance from the tungsten electrode to the welding point. The arc voltage depends on the change of the arc length. When the arc is elongated, the arc voltage increases, and when the arc length becomes shorter, the arc voltage decreases. The arc voltage is adjusted by adjusting the distance from the tungsten electrode to the welding point.

[0013] The arc voltage tracking strategy includes arc voltage distance control rules and distance speed control rules. The arc voltage distance control rules are established as follows:

[0014] Let e(k)=U set -U(k), where, U setis the optimal welding arc voltage set according to the welding process requirements of the TIG welding equipment; U(k) is the actual welding arc voltage collected by the arc voltage acquisition module at the kth sampling moment; e(k) is the deviation between the actual welding arc voltage measured at the kth sampling moment and the optimal welding arc voltage; e(k-1) and e(k-2) represent the deviation between the actual welding arc voltage and the optimal welding arc voltage at the k-1st and k-2nd sampling moments, respectively, and

[0015]

[0016] In formula (2), Δ 2 e(k) is the quadratic difference between the actual welding arc voltage measured at the kth sampling moment and the optimal welding arc voltage deviation; Δe(k) is related to Δ 2 e(k) represents the changing trend of e(k) and Δe(k); V Y (k) is the welding gun feed speed; V(k) is the vertical movement speed of the welding gun, e(k) and Δu(k) are respectively used as the input and output at the kth sampling moment. When e(k) is in [E max , +∞] interval, the Δu(k) value is ΔU max ; When e(k) is in (E set1 , E max ) interval, the Δu(k) value is k1[k P ·Δe(k)+k i e(k)+k d ·Δ 2 e(k)]; when e(k) is in (0, E set1 ) interval, the Δu(k) value is k2k P e m (k); when e(k) is 0, Δu(k) is 0; when e(k) is in the interval (E set2 , 0), Δu(k) value is k2k P e m (k); when e(k) is in the interval (E min , E set2 ), the Δu(k) value is k1[k P ·Δe(k)+k i e(k)+k d ·Δ 2 e(k)]; when e(k) is in the interval (-∞, E min ), the value of Δu(k) is ΔU min ;

[0017] The welding gun feed distance is calculated based on Δu(k) and formula (1);

[0018] With e(k) and V Y(k) is the input, V(k) is the vertical moving speed of the welding gun, and as the output, when e(k) is in [E max , +∞] interval, V Y (k) is in [V set2 , V max ] interval, V(k) value is V1; when e(k) is in [E max , +∞] interval, V Y (k) is in (V set1 , V set2 ) interval, V(k) value is V2; when e(k) is in [E max , +∞] interval, V Y (k) is in (0, V set1 ] interval, V(k) value is V3; when e(k) is in (E ser1 , E max ) interval, V Y (k) is in [V set2 , V max ] interval, V(k) value is V4; when e(k) is in (E set1 , E max ) interval, V Y (k) is in (V set1 , V set2 ) interval, V(k) value is V5; when e(k) is in (E set1 , E max ) interval, V Y (k) is in (0, V set1 ] interval, V(k) value is V6; when e(k) is in (0, E set1 ] interval, V Y (k) is in [V set2 , V max ] interval, V(k) value is V7; when e(k) is in (0, E set1 ] interval, V Y (k) is in (V set1 , V set2 ) interval, V(k) value is V8; when e(k) is in (0, E set1 ] interval, V Y (k) is in (0, V set1 ] interval, V(k) value is V9; when e(k) is 0, V Y (k) is in [V set2 , V max ] interval, V(k) value is V 10 ; When e(k) is 0, V Y (k) is in (V set1 , V set2 ) interval, V(k) value is V11 ; When e(k) is 0, V Y (k) is in (0, V set1 ] interval, V(k) value is V 12 ; When e(k) is in (E set3 ,0) interval,V Y (k) is in [V set2 , V max ] interval, V(k) value is V7; when e(k) is in (E set3 ,0) interval,V Y (k) is in (V set1 , V set2 ) interval, V(k) value is V8; when e(k) is in (E set3 ,0) interval,V Y (k) is in (0, V set1 ] interval, V(k) value is V9; when e(k) is in (E set3 , E set2 ] interval, V Y (k) is in [V set2 , V max ] interval, V(k) value is V4; when e(k) is in (E set3 , E set2 ] interval, V Y (k) is in (V set1 , V set2 ) interval, V(k) value is V5; when e(k) is in (E set3 , E set2 ] interval, V Y (k) is in (0, V set1 ] interval, V(k) value is V6; when e(k) is in (E min , E set3 ] interval, V Y (k) is in [V set2 , V max ] interval, V(k) value is V1; when e(k) is in (E min , E set3 ] interval, V Y (k) is in (V set1 , V set2 ) interval, V(k) value is V2; when e(k) is in (E min , E set3 ] interval, V Y (k) is in (0, V set1 ] interval, the V(k) value is V3.

[0019] An arc welding system includes a welding controller, a six-axis robot, a No. 1 robot controller, an argon gas cylinder, a flow controller, a welding power supply, a cooling water tank, a welding gun, an arc voltage acquisition module, a temperature sensor, a visual sensor, a trajectory tracking and measurement module, a right-angle robot and a No. 2 robot controller, wherein the welding gun for welding plates is installed on the six-axis robot, the six-axis robot is connected to the No. 1 robot controller, a flow controller is installed on the argon gas cylinder, the welding power supply, the argon gas cylinder and the cooling water tank are connected to the welding gun via electricity, water and gas pipelines, respectively, the No. 1 robot controller, the flow controller, the arc voltage acquisition module, the temperature sensor, the trajectory tracking and measurement module, the No. 2 robot controller and the welding power supply are respectively connected to the welding controller, the arc voltage acquisition module collects the arc voltage of the plate and sends it to the welding controller, the temperature sensor and the visual sensor are installed on the right-angle robot, the trajectory tracking and measurement module is connected to the visual sensor and the right-angle robot, and the right-angle robot is connected to the No. 2 robot controller.

[0020] In the present invention, the first robot controller receives the instruction from the welding controller to control the six-axis robot to adjust the spatial position, posture and moving speed of the welding gun, and sends the spatial position information of the welding gun to the welding controller;

[0021] The No. 2 robot controller receives the instruction from the welding controller and controls the rectangular robot to adjust the positions of the temperature sensor and the visual sensor, and sends the position information of the temperature sensor and the visual sensor to the welding controller;

[0022] The temperature sensor measures the temperature around the weld in real time and sends it to the welding controller. The welding controller calculates the process parameters of the welding gun and visual sensor movement speed, welding current, and argon flow rate based on the adjustment strategy. The process parameters are then sent to the No. 2 robot controller, welding power supply, and flow controller respectively.

[0023] The visual sensor obtains the weld trajectory information and sends it to the trajectory tracking and measurement module. The welding controller transmits the welding gun spatial position and posture information sent by the No. 1 robot controller and the visual sensor position information sent by the No. 2 robot controller to the trajectory tracking and measurement module. The trajectory tracking and measurement module calculates the welding gun feed coordinates, welding gun posture, and visual sensor movement coordinates and sends these data to the welding controller. The welding controller transmits the welding gun feed coordinates and welding gun posture to the No. 1 robot controller and transmits the visual sensor movement coordinates to the No. 2 robot controller.

[0024] The welding gun posture is that the welding gun is in the tangent direction of the weld trajectory and forms a certain angle with the plate;

[0025] The welding controller controls the flow controller, thereby controlling the argon flow;

[0026] The arc voltage acquisition module collects the arc voltage of the plate and sends it to the welding controller. The welding controller calculates the welding gun feed distance and welding gun feed speed based on the arc voltage tracking strategy, and sends it to the No. 1 robot controller to control the energy output of the welding gun.

[0027] Beneficial effects: The present invention can realize the function of direct welding without complicated teaching, effectively improve work efficiency, and can adjust the welding arc length in real time to compensate for the change in welding distance caused by the deformation of the welding plate, thereby reducing the occurrence of welding defects; adjust the energy output of the welding gun in real time to avoid the occurrence of welding defects such as weld leakage due to the excessive temperature of the welding plate itself and the energy output of the welding gun, thereby improving the welding quality, which is a powerful supplement to TIG welding control. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 Schematic diagram of the connection of the arc welding system in a preferred embodiment of the present invention.

[0029] Figure 2 Schematic diagram of welding trajectory of welding gun in a preferred embodiment of the present invention.

[0030] Figure 3 Schematic diagram of welding trajectory tracking of a welding gun in a preferred embodiment of the present invention.

[0031] Figure 4 Schematic diagram of welding arc voltage tracking of a welding gun in a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0032] In order to make the technical means, creative features, objectives and effects achieved by the present invention easier to understand, the present invention is further described below with reference to specific illustrations.

[0033] An arc welding method uses an arc welding system for welding, and the specific steps are as follows:

[0034] (1) In the arc welding system, the right-angle robot and the six-axis robot control the visual sensor and the welding gun to move to the initial point of the weld. The weld trajectory is as follows: Figure 2 As shown, the welding parameters at the initial point of the weld are: current 200A, welding speed 18mm / s, arc voltage 18V, and argon flow rate 7.5L / min;

[0035] (2) Figure 3As shown, after welding is started from the initial point of the weld, the visual sensor sends the acquired welding trajectory information to the trajectory tracking and measurement module, and the welding controller transmits the welding gun spatial position and posture information sent by the No. 1 robot controller and the visual sensor position information sent by the No. 2 robot controller to the trajectory tracking and measurement module. The trajectory tracking and measurement module calculates the welding gun feed coordinates, welding gun posture, and visual sensor movement coordinates, and sends them to the welding controller. The welding controller sends the welding gun feed coordinates and welding gun posture to the No. 1 robot controller, and transmits the visual sensor movement coordinates to the No. 2 robot controller. The No. 1 robot controller controls the six-axis robot to move to the welding gun feed coordinates, and adjusts the welding gun posture to the tangent direction of the weld trajectory. The No. 2 robot controller controls the movement of the visual sensor.

[0036] (3) Figure 4 As shown in the figure, after starting welding, the arc voltage acquisition module collects the arc voltage of the TIG welding plate at a frequency of 1000Hz and sends it to the welding controller. The welding controller performs LMS filtering on the received arc voltage to obtain a smooth arc voltage, and then calculates the welding gun feed distance and welding gun feed speed based on the smooth arc voltage and arc pressure tracking strategy. The welding gun feed distance and welding gun feed speed are then sent to the No. 1 robot controller. The No. 1 robot controller controls the six-axis robot to execute the calculated welding gun feed distance and welding gun feed speed to change the distance from the welding gun to the welding plate and the moving speed of the welding gun in the vertical direction, thereby realizing the adjustment of the arc voltage and arc pressure tracking speed;

[0037] The relationship between the arc voltage and the arc length (the distance from the tungsten electrode to the welding point) can be expressed as U h =U Z +K·L(1)

[0038] In formula (1), U h is the arc voltage, U Z It is the sum of the cathode voltage drop and the anode voltage drop under certain conditions (certain current and electrode material), K is the arc voltage gradient, which is a proportional constant, and L is the distance from the tungsten electrode to the welding point. The arc voltage depends on the change of the arc length. When the arc is elongated, the arc voltage increases, and when the arc length becomes shorter, the arc voltage decreases. The arc voltage is adjusted by adjusting the distance from the tungsten electrode to the welding point.

[0039] The arc voltage tracking strategy includes arc voltage distance control rules and distance speed control rules. The arc voltage distance control rules are established as follows:

[0040] Let e(k)=U set -U(k), where, U setis the optimal welding arc voltage set according to the welding process requirements of the TIG welding equipment; U(k) is the actual welding arc voltage collected by the arc voltage acquisition module at the kth sampling moment; e(k) is the deviation between the actual welding arc voltage measured at the kth sampling moment and the optimal welding arc voltage; e(k-1) and e(k-2) represent the deviation between the actual welding arc voltage and the optimal welding arc voltage at the k-1st and k-2nd sampling moments, respectively, and

[0041]

[0042] In formula (2), Δ 2 e(k) is the quadratic difference between the actual welding arc voltage measured at the kth sampling moment and the optimal welding arc voltage deviation; Δe(k) is related to Δ 2 e(k) represents the changing trend of e(k) and Δe(k); V Y (k) is the welding gun feed speed; V(k) is the vertical movement speed of the welding gun. e(k) and Δu(k) are respectively used as the input and output at the kth sampling moment. The arc voltage adjustment control rule is shown in Table 1. When e(k) is in [E max , +∞] interval, the Δu(k) value is ΔU max ; When e(k) is in (E set1 , E max ) interval, the Δu(k) value is k1[k P ·Δe(k)+k i e(k)+k d ·Δ 2 e(k)]; when e(k) is in (0, E set1 ) interval, the Δu(k) value is k2k P e m (k); when e(k) is 0, Δu(k) is 0; when e(k) is in the interval (E set2 , 0), Δu(k) value is k2k P e m (k); when e(k) is in the interval (E min , E set2 ), the Δu(k) value is k1[k P ·Δe(k)+k i e(k)+k d ·Δ 2 e(k)]; when e(k) is in the interval (-∞, E min ), the value of Δu(k) is ΔU min ;

[0043] Table 1 Arc voltage distance control rules

[0044]

[0045] Note: E max 、E min 、E set1 、E set2 are all set deviation limits, and E min <E set2 <0 <E set1 <E max ; k1 is the gain amplification factor, and k1>1; k2 is the suppression factor, and 0 <k2<1;k p 、k i 、k d are the proportional, integral and differential coefficients of PID control respectively; e m (k) is the maximum value among e(k), e(k-1), and e(k-2);

[0046] The welding gun feed distance is calculated based on Δu(k) and formula (1);

[0047] With e(k) and V Y (k) is the input, V(k) is the vertical moving speed of the welding gun, and as the output, the speed adjustment control rule is shown in Table 2. When e(k) is in [E max , +∞] interval, V Y (k) is in [V set2 , V max ] interval, V(k) value is V1; when e(k) is in [E max , +∞] interval, V Y (k) is in (V set1 , V set2 ) interval, V(k) value is V2; when e(k) is in [E max , +∞] interval, V Y (k) is in (0, V set1 ] interval, V(k) value is V3; when e(k) is in (E set1 , E max ) interval, V Y (k) is in [V set2 , V max ] interval, V(k) value is V4; when e(k) is in (E set1 , E max ) interval, V Y (k) is in (V set1 , V set2 ) interval, V(k) value is V5; when e(k) is in (E set1 , E max ) interval, V Y (k) is in (0, V set1 ] interval, V(k) value is V6; when e(k) is in (0, E set1] interval, V Y (k) is in [V set2 , V max ] interval, V(k) value is V7; when e(k) is in (0, E set1 ] interval, V Y (k) is in (V set1 , V set2 ) interval, V(k) value is V8; when e(k) is in (0, E set1 ] interval, V Y (k) is in (0, V set1 ] interval, V(k) value is V9; when e(k) is 0, V Y (k) is in [V set2 , V max ] interval, V(k) value is V 10 ; When e(k) is 0, V Y (k) is in (V set1 , V set2 ) interval, V(k) value is V 11 ; When e(k) is 0, V Y (k) is in (0, V set1 ] interval, V(k) value is V 12 ; When e(k) is in (E set3 ,0) interval,V Y (k) is in [V set2 , V max ] interval, V(k) value is V7; when e(k) is in (E set3 ,0) interval,V Y (k) is in (V set1 , V set2 ) interval, V(k) value is V8; when e(k) is in (E set3 ,0) interval,V Y (k) is in (0, V set1 ] interval, V(k) value is V9; when e(k) is in (E set3 , E set2 ] interval, V Y (k) is in [V set2 , V max ] interval, V(k) value is V4; when e(k) is in (E set3 , E set2 ] interval, V Y (k) is in (V set1 , V set2 ) interval, V(k) value is V5; when e(k) is in (E set3 , E set2 ] interval, V Y (k) is in (0, Vset1 ] interval, V(k) value is V6; when e(k) is in (E min , E set3 ] interval, V Y (k) is in [V set2 , V max ] interval, V(k) value is V1; when e(k) is in (E min , E set3 ] interval, V Y (k) is in (V set1 , V set2 ) interval, V(k) value is V2; when e(k) is in (E min , E set3 ] interval, V Y (k) is in (0, V set1 ] interval, V(k) value is V3;

[0048] Table 2 Pitch speed control rules

[0049]

[0050]

[0051] Note: E max 、E min 、E set1 、E set2 、E set3 are all set deviation limits, and E min <E set3 <E set2 <0 <E set1 <E max ;E max 、V set1 、V set2 are all set speed limit values, and 0 <V set1 <V set2 <V max ;

[0052] (4) After starting welding, the temperature sensor sends the collected temperature to the welding controller, which then filters the temperature through the SG filter to obtain a smoothed temperature. The welding controller calculates the latest moving speed, welding current, and argon flow of the welding gun and visual sensor based on the smoothed temperature and the moving speed, welding current, and argon flow of the welding gun and visual sensor. The welding controller then sends the moving speed of the welding gun to the No. 1 robot controller, the moving speed of the visual sensor to the No. 2 robot controller, the welding current to the welding power supply, and the argon flow to the flow controller, thereby controlling the energy output of the welding gun at the weld.

[0053] An arc welding system includes a welding controller, a six-axis robot, a No. 1 robot controller, an argon gas cylinder, a flow controller, a welding power supply, a cooling water tank, a welding gun, an arc voltage acquisition module, a temperature sensor, a visual sensor, a trajectory tracking and measurement module, a right-angle robot and a No. 2 robot controller, wherein a welding gun for welding plates is installed on the six-axis robot, the six-axis robot is connected to the No. 1 robot controller, a flow controller is installed on the argon gas cylinder, the welding power supply, the argon gas cylinder and the cooling water tank are connected to the welding gun via electricity, water and gas pipelines, respectively, the No. 1 robot controller, the flow controller, the arc voltage acquisition module, the temperature sensor, the trajectory tracking and measurement module, the No. 2 robot controller and the welding power supply are respectively connected to the welding controller, the arc voltage acquisition module collects the arc voltage of the welding gun and sends it to the welding controller, the temperature sensor and the visual sensor are installed on the right-angle robot, the trajectory tracking and measurement module is connected to the visual sensor and the right-angle robot, and the right-angle robot is connected to the No. 2 robot controller.

[0054] In this embodiment, the first robot controller receives the instruction of the welding controller to control the six-axis robot to adjust the spatial position, posture and moving speed of the welding gun, and sends the spatial position information of the welding gun to the welding controller;

[0055] The No. 2 robot controller receives the instruction from the welding controller and controls the rectangular robot to adjust the positions of the temperature sensor and the visual sensor, and sends the position information of the temperature sensor and the visual sensor to the welding controller;

[0056] The temperature sensor measures the temperature around the weld in real time and sends it to the welding controller. The welding controller calculates the process parameters of the welding gun and visual sensor movement speed, welding current, and argon flow rate based on the adjustment strategy. The process parameters are then sent to the No. 2 robot controller, welding power supply, and flow controller respectively.

[0057] The visual sensor obtains the weld trajectory information and sends it to the trajectory tracking and measurement module. The welding controller transmits the welding gun spatial position and posture information sent by the No. 1 robot controller and the visual sensor position information sent by the No. 2 robot controller to the trajectory tracking and measurement module. The trajectory tracking and measurement module calculates the welding gun feed coordinates, welding gun posture, and visual sensor movement coordinates and sends these data to the welding controller. The welding controller transmits the welding gun feed coordinates and welding gun posture to the No. 1 robot controller and transmits the visual sensor movement coordinates to the No. 2 robot controller.

[0058] The welding gun posture is that the welding gun is in the tangent direction of the weld trajectory and forms a certain angle with the plate;

[0059] The welding controller controls the flow controller, thereby controlling the argon flow;

[0060] The arc voltage acquisition module collects the arc voltage of the welding gun and sends it to the welding controller. The welding controller calculates the welding gun feed distance and welding gun feed speed based on the arc voltage tracking strategy, and sends it to the No. 1 robot controller to control the energy output of the welding gun.

Claims

1. An arc welding method, characterized in that: An arc welding system is used for welding, and the arc welding system includes a welding controller, a six-axis robot, a No. 1 robot controller, an argon cylinder, a flow controller, a welding power supply, a welding gun, an arc voltage acquisition module, a visual sensor, a trajectory tracking and measurement module, a right-angle robot, and a No. 2 robot controller. The welding gun for welding the plate is installed on the six-axis robot, the six-axis robot is connected to the No. 1 robot controller, a flow controller is installed on the argon cylinder, the welding power supply and the argon cylinder are connected to the welding gun, the No. 1 robot controller, the flow controller, the arc voltage acquisition module, the temperature sensor, the trajectory tracking and measurement module, the No. 2 robot controller, and the welding power supply are respectively connected to the welding controller, the arc voltage acquisition module collects the arc voltage of the plate and sends it to the welding controller, the visual sensor is installed on the right-angle robot, the trajectory tracking and measurement module is connected to the visual sensor and the right-angle robot, and the right-angle robot is connected to the No. 2 robot controller. The specific steps are as follows: (1) In the arc welding system, the right-angle robot controls the visual sensor and the six-axis robot controls the welding gun to move to the initial point of the weld. (2) After welding starts from the initial point of the weld, the visual sensor sends the acquired welding trajectory information to the trajectory tracking and measurement module. The welding controller transmits the welding gun spatial position and posture information sent by the No. 1 robot controller and the visual sensor position information sent by the No. 2 robot controller to the trajectory tracking and measurement module. The trajectory tracking and measurement module calculates the welding gun feed coordinates, welding gun posture, and visual sensor movement coordinate information and sends them to the welding controller. The welding controller sends the welding gun feed coordinates and welding gun posture information to the No. 1 robot controller and transmits the visual sensor movement coordinate information to the No. 2 robot controller. The No. 1 robot controller controls the six-axis robot to move to the welding gun feed coordinates and adjusts the welding gun posture to the tangent direction of the weld trajectory. The No. 2 robot controller controls the movement of the visual sensor. (3) After starting welding, the arc voltage acquisition module collects the arc voltage of the plate and sends it to the welding controller. The welding controller performs LMS filtering on the received arc voltage to obtain a smooth arc voltage, and then calculates the welding gun feed distance and welding gun feed speed based on the smooth arc voltage and arc pressure tracking strategy. The welding gun feed distance and welding gun feed speed are then sent to the No. 1 robot controller. The No. 1 robot controller controls the six-axis robot to execute the calculated welding gun feed distance and welding gun feed speed, thereby changing the distance from the welding gun to the welding plate and the moving speed of the welding gun in the vertical direction, thereby adjusting the arc voltage and arc pressure tracking speed. (4) After starting welding, the temperature sensor sends the collected temperature to the welding controller, which then filters the collected temperature through SG filtering to obtain a smoothed temperature. The welding controller calculates the latest moving speed, welding current, and argon flow of the welding gun and visual sensor based on the smoothed temperature and the moving speed, welding current, and argon flow of the welding gun and visual sensor. It then sends the moving speed of the welding gun to the No. 1 robot controller, the moving speed of the visual sensor to the No. 2 robot controller, the welding current to the welding power supply, and the argon flow to the flow controller, thereby controlling the energy output of the welding gun at the weld of the plate.

2. The arc welding method according to claim 1, wherein: The relationship between arc voltage and arc length is expressed as U h =U Z +K·L(1) In formula (1), U h is the arc voltage, U Z It is the sum of the cathode voltage drop and the anode voltage drop under certain conditions, K is the arc voltage gradient, which is a proportional constant, and L is the distance from the tungsten electrode to the welding point.

3. The arc welding method according to claim 1, wherein: The arc voltage tracking strategy includes arc voltage distance control rules and distance speed control rules. The arc voltage distance control rules are established as follows: Let e(k)=U set -U(k), where, U set is the optimal welding arc voltage set according to the welding process requirements of the TIG welding equipment; U(k) is the actual welding arc voltage collected by the arc voltage acquisition module at the kth sampling moment; e(k) is the deviation between the actual welding arc voltage measured at the kth sampling moment and the optimal welding arc voltage; e(k-1) and e(k-2) represent the deviation between the actual welding arc voltage and the optimal welding arc voltage at the k-1st and k-2nd sampling moments, respectively, and In formula (2), △ 2 e(k) is the quadratic difference between the actual welding arc voltage measured at the kth sampling moment and the optimal welding arc voltage deviation; △e(k) and △ 2 e(k) represents the changing trend of e(k) and △e(k); V Y (k) is the welding gun feed speed; V(k) is the vertical movement speed of the welding gun, and e(k) and △u(k) are respectively used as the input and output at the kth sampling moment. According to △u(k) and U h =U Z +K·L, calculate the welding gun feed distance, where U h is the arc voltage, U Z It is the sum of the cathode voltage drop and the anode voltage drop under certain conditions, K is the arc voltage gradient, which is a proportional constant, and L is the distance from the tungsten electrode to the welding point.

4. The arc welding method according to claim 3, wherein: With e(k) and V Y (k) is taken as input, and according to the speed control rule of the pitch adjustment, V(k) is calculated as the moving speed of the welding gun in the vertical direction.

5. The arc welding method according to claim 1, wherein: The welding gun posture is that the welding gun is in the tangent direction of the weld trajectory and forms a certain angle with the plate.

6. The arc welding method according to claim 1, wherein: A temperature sensor is installed on the rectangular robot.

7. The arc welding method according to claim 1, wherein: The welding gun is connected to the cooling water tank.

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