Swing welding arc tracking method and device based on end stop, six-axis industrial robot, computer equipment, storage medium and computer program product

Abstract

The invention relates to a swing welding arc tracking method and device based on end stop, computer equipment, a storage medium and a computer program product. The method comprises the steps that a control instruction is sent to a welding gun so as to indicate the welding gun to conduct swing welding on a welding seam of a to-be-welded workpiece according to a preset swing welding mode, and the welding gun stays for a preset duration when moving to the two ends of the swing direction of the welding gun; acquiring an arc tracking current signal in a reference welding period as a reference current signal; a current arc tracking current signal in the current welding period is obtained; determining current offset information according to the current arc tracking current signal and the reference current signal; under the condition that the current deviation information represents that the swing welding coordinate system deviates, a new control instruction is generated according to the current deviation information, and the new control instruction is sent to a welding gun; the new control instruction is used for indicating the welding gun to adjust the position of the swing welding coordinate system, so that the current generated by welding continuously tracks the reference current signal. By adopting the method, the welding effect can be improved.

Description

Technical Field

[0001] This application relates to the field of automatic control technology, and in particular to a method, apparatus, six-axis industrial robot, computer equipment, storage medium and computer program product based on end-dwelling oscillating welding arc tracking. Background Technology

[0002] Arc tracking is a crucial step in welding automation to ensure that the welding torch always travels along the center of the joint.

[0003] Currently, existing arc tracking methods typically employ zigzag or sinusoidal oscillation patterns. However, these oscillation patterns experience significant impact at the inflection point, leading to increased vibration and spatter, which negatively impacts welding quality. Furthermore, they do not yield satisfactory welding results in applications with excessively large weld seams or excessively long welding wires, demonstrating limited versatility.

[0004] Therefore, the traditional welding technique suffers from poor welding results due to the arc tracking method used in the welding torch. Summary of the Invention

[0005] Therefore, it is necessary to provide a method, apparatus, six-axis industrial robot, computer equipment, computer-readable storage medium, and computer program product based on end-dwelling oscillating arc tracking that can improve welding results, addressing the aforementioned technical problems.

[0006] A method for tracking the tumbling welding arc based on end-dwelling, comprising:

[0007] Send control commands to the welding torch; the control commands are used to instruct the welding torch to perform oscillating welding on the weld seam of the workpiece to be welded according to the preset oscillating welding method, and to stay for a preset duration when it moves to both ends of the oscillation direction of the welding torch;

[0008] The arc tracking current signal within the reference welding cycle is acquired and used as the reference current signal;

[0009] Obtain the current arc tracking current signal within the current welding cycle; the current welding cycle is any welding cycle after the reference welding cycle;

[0010] Based on the current arc tracking current signal and the reference current signal, determine the current offset information;

[0011] When the current offset information indicates that the oscillating welding coordinate system has shifted, a new control command is generated based on the current offset information and sent to the welding torch. The oscillating welding coordinate system has the welding torch as the origin, the weld direction of the workpiece to be welded as the horizontal axis, the oscillation direction of the welding torch as the vertical axis, and the opposite direction of the welding torch as the vertical axis. The new control command is used to instruct the welding torch to adjust the position of the oscillating welding coordinate system so that the current generated by welding continuously tracks the reference current signal, thereby achieving weld tracking.

[0012] In one embodiment, current offset information is determined based on the current arc tracking current signal and the reference current signal, including:

[0013] Based on the current arc tracking current signal, determine the current current difference and current average current value within the current welding cycle; and based on the reference current signal, determine the reference current difference and reference average current value.

[0014] The result of subtracting the reference current difference from the current current difference is taken as the current difference component corresponding to the current welding cycle, and the result of subtracting the reference average current value from the current average current value is taken as the average current difference component corresponding to the current welding cycle.

[0015] The current difference component and the average current difference component are used as current offset information.

[0016] In one embodiment, determining the current current difference within the current welding cycle based on the current arc tracking current signal includes:

[0017] Within a preset range around the start of the current welding cycle, search for the local maximum value of the arc tracking current, and within a preset range around the midpoint of the current welding cycle, search for the local minimum value of the arc tracking current.

[0018] The result of subtracting the local minimum value of the arc tracking current from the local maximum value is used as the current difference.

[0019] In one embodiment, a new control command is generated based on the current offset information, including:

[0020] The current difference component is input into the left-right offset determination model to obtain the vertical axis offset for the oscillating welding coordinate system. Similarly, the average current difference component is input into the up-down offset determination model to obtain the vertical axis offset for the oscillating welding coordinate system. The left-right offset determination model is pre-fitted based on the left-right offset current difference dataset, which includes multiple sets of current difference values ​​corresponding to left or right offsets in the oscillating welding coordinate system. The up-down offset determination model is pre-fitted based on the up-down offset current difference dataset, which includes multiple sets of current difference values ​​corresponding to up or down offsets in the oscillating welding coordinate system.

[0021] The control values ​​are determined based on the vertical axis offset and the vertical axis offset; the control values ​​are used to compensate for the welding torch offset.

[0022] Based on the control quantity, generate new control instructions.

[0023] In one embodiment, acquiring the current arc tracking current signal within the current welding cycle includes:

[0024] Acquire the initial arc tracking current signal within the current welding cycle;

[0025] The initial arc tracking current signal is filtered to obtain the filtered signal.

[0026] The filtered signal is inversely transformed to obtain the current arc tracking current signal.

[0027] A tack welding arc tracking device based on end-dwelling, comprising:

[0028] The sending module is used to send control commands to the welding torch; the control commands are used to instruct the welding torch to perform sway welding on the weld seam of the workpiece to be welded according to the preset sway welding method, and to stay for a preset duration when it moves to both ends of the swaying direction of the welding torch;

[0029] The first acquisition module is used to acquire the arc tracking current signal within the reference welding cycle as a reference current signal;

[0030] The second acquisition module is used to acquire the current arc tracking current signal within the current welding cycle; the current welding cycle is any welding cycle after the reference welding cycle;

[0031] The determination module is used to determine the current offset information based on the current arc tracking current signal and the reference current signal;

[0032] The generation module is used to generate new control commands based on the current offset information when the current offset information indicates that the oscillating welding coordinate system has shifted, and send the new control commands to the welding torch. The oscillating welding coordinate system has the welding torch as the origin, the weld direction of the workpiece to be welded as the horizontal axis, the oscillation direction of the welding torch as the vertical axis, and the opposite direction of the welding torch as the vertical axis. The new control commands are used to instruct the welding torch to adjust the position of the oscillating welding coordinate system so that the current generated by welding continuously tracks the reference current signal, thereby achieving weld tracking.

[0033] A six-axis industrial robot for welding includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps of the method described above.

[0034] A computer device includes a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the method described above.

[0035] A computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the method described above.

[0036] A computer program product includes a computer program that, when executed by a processor, implements the steps of the method described above.

[0037] The aforementioned arc tracking method, apparatus, six-axis industrial robot, computer equipment, storage medium, and computer program product based on end-dwelling oscillating welding arc tracking, involves sending control commands to the welding torch; these control commands instruct the welding torch to perform oscillating welding on the weld seam of the workpiece to be welded according to a preset oscillating welding method, and to pause for a preset duration when moving to either end of the oscillation direction of the welding torch; acquiring the arc tracking current signal within a reference welding cycle as a reference current signal; acquiring the current arc tracking current signal within the current welding cycle; the current welding cycle being any welding cycle after the reference welding cycle; determining current offset information based on the current arc tracking current signal and the reference current signal; and generating new control commands based on the current offset information when the current offset information indicates a shift in the oscillating welding coordinate system, and sending the new control commands to the welding torch; the oscillating welding coordinate system has the welding torch as its origin and the workpiece to be welded as its coordinate axis. The weld direction is the horizontal axis, the welding torch swing direction is the vertical axis, and the opposite direction of the welding torch is the vertical axis. The new control commands are used to instruct the welding torch to adjust the position of the oscillation welding coordinate system so that the welding current continuously tracks the reference current signal, thus achieving weld tracking. In this way, the addition of the end-stop arc tracking method can reduce the vibration and spatter caused by the large impact when the welding torch swings to the inflection point, improve the welding process effect, and have a stronger generalization ability in application scenarios with large welds and excessively long welding wires. Furthermore, it can adaptively extract the reference current signal according to the current difference caused by different welding workpiece thicknesses and different welding currents, effectively reducing the testing environment required before welding and increasing welding efficiency. At the same time, it can complete deviation detection based solely on the welding current signal without relying on external optical sensors and arc sensors, making it easy to deploy quickly on robots or welding applications. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments or related technologies of this application, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a flowchart illustrating a method for tracking a tumbling welding arc based on end-dwelling in one embodiment.

[0040] Figure 2 This is a schematic diagram of a current waveform after noise removal via low-pass filtering in one embodiment.

[0041] Figure 3 This is a schematic diagram of a current waveform after discrete Fourier transform in one embodiment;

[0042] Figure 4 This is a flowchart illustrating a method for tracking a tumbling welding arc based on end-dwelling in one embodiment.

[0043] Figure 5 This is a flowchart illustrating a poling arc tracking method based on end-dwelling in another embodiment;

[0044] Figure 6 This is a structural block diagram of a tumbling arc tracking device based on end-dwelling in one embodiment;

[0045] Figure 7 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0047] Arc tracking is a crucial step in welding automation to ensure the welding torch always travels along the center of the joint. Common implementation methods in industrial settings generally fall into two categories: one is external sensing imaging (such as laser profilometry, structured light, binocular / infrared vision), which directly extracts the weld geometry before / during welding; the other is "arc-sensing," which directly utilizes the characteristics of the welding machine's power output and the arc's own signal for feedback, without relying on external optical devices. Practice shows that "arc-sensing" offers advantages such as low cost, strong environmental adaptability, and insensitivity to spatter in scenarios involving thick plates and large assembly deviations. Its basic idea is that during oscillating welding, the welding torch oscillates left and right. When it reaches the left or right boundary, the torch is closest to the workpiece, and the current is maximum; when it passes the weld centerline, the torch is furthest from the workpiece, and the current is minimum. When the welding torch's oscillation centerline deviates from the weld centerline, the two peak current values ​​within the cycle will change. Based on this characteristic of the current value changing with the offset, real-time tracking of the weld can be achieved. Based on the mechanism of "signal-oscillation-deviation", current algorithms for weld deviation extraction generally include the limit position current difference method, the left and right interval current integral difference method, and the characteristic harmonic detection method.

[0048] However, traditional arc tracking methods typically employ Z-shaped or sinusoidal oscillations. This type of oscillation welding often results in insufficient heat absorption on the sidewalls, uneven penetration and weld formation, and the large impact at the inflection point can lead to increased vibration and spatter, affecting both the welding process and the arc tracking effect. To address this issue, existing research suggests adding end-dwell time during oscillation welding to effectively reduce the impact of these problems. However, there is currently limited research on how to incorporate end-dwell time into the arc tracking field. This application proposes an arc tracking method that incorporates dwell time at both ends during Z-shaped oscillation welding, which can effectively achieve better welding process and weld seam tracking without the need for external sensors.

[0049] The end-dwelling arc tracking method for oscillating welding provided in this application effectively improves the welding process and has stronger generalization ability and versatility in different application scenarios. When faced with welding workpieces of different thicknesses and current differences caused by different welding currents, it adaptively extracts the reference current after arc initiation, effectively reducing the testing steps required before welding, increasing welding efficiency, and exhibiting good adaptability. The FFT filtering can adaptively select the frequency generated by oscillating welding as the desired frequency, and reconstruct the current signal using this frequency to achieve feature extraction of the current signal. It has high applicability to various oscillating welding frequencies and high stability.

[0050] The arc tracking method based on end-dwelling provided in this application can be applied to six-axis industrial robots. The six-axis industrial robot's controller sends control commands to the welding torch. These commands instruct the torch to perform swaying welding on the weld seam of the workpiece according to a preset swaying welding method, and to pause for a preset duration when it reaches either end of the torch's swaying direction. The controller acquires the arc tracking current signal within a reference welding cycle as a reference current signal. It also acquires the current arc tracking current signal within the current welding cycle, which is any welding cycle following the reference welding cycle. Based on the current arc tracking current signal and the reference current signal, the controller determines the current offset information. When the current offset information indicates a shift in the swaying welding coordinate system, the controller generates new control commands based on the current offset information and sends these commands to the welding torch. The swaying welding coordinate system has the welding torch as its origin, the weld seam direction of the workpiece as its horizontal axis, the swaying direction of the welding torch as its vertical axis, and the opposite direction of the welding torch's direction as its vertical axis. The new control commands instruct the welding torch to adjust the position of the swaying welding coordinate system so that the welding current continuously tracks the reference current signal, achieving weld seam tracking.

[0051] In one exemplary embodiment, such as Figure 1As shown, a method for tracking the arc of a welding machine based on end-dwelling is provided. Taking the application of this method to the controller of a six-axis industrial robot as an example, the method includes the following steps S102 to S110. Wherein:

[0052] Step S102: Send a control command to the welding torch; the control command is used to instruct the welding torch to perform sway welding on the weld seam of the workpiece to be welded in a preset sway welding manner, and to stay for a preset time when it moves to both ends of the swaying direction of the welding torch.

[0053] Among them, the control command can be a command used to control the movement of the welding torch, which enables the welding torch to swing and weld the weld seam of the workpiece to be welded in a preset swing welding mode, and to make the welding torch stay for a preset time when it moves to the left and right boundaries of its swing direction.

[0054] Among them, the preset oscillating welding method can refer to Z-shaped oscillating welding method, sinusoidal oscillating welding method, etc.

[0055] The workpiece to be welded can refer to a workpiece whose weld has not yet been welded.

[0056] The two ends of the swing direction of the welding torch can refer to the left and right boundaries of the swing direction of the welding torch.

[0057] The preset duration can be set according to the actual situation. For example, it can be set to 0.1s. When the preset duration is set to 0.1s, the welding torch will pause for 0.1s at the end when it moves to the left or right boundary of its swing direction.

[0058] Optionally, the controller of the six-axis industrial robot controls the welding torch to start arc tracking after moving to the teaching starting point and sends control commands to the welding torch. Upon receiving the control commands, the welding torch performs oscillating welding on the weld seam of the workpiece to be welded according to the instructions of the control commands and in accordance with the preset oscillating welding method. When the welding torch moves to the left and right boundaries of its oscillation direction, it pauses at the end for a preset time.

[0059] The aforementioned arc tracking refers to a control method that, during the fusion welding process, estimates the relative deviation between the welding torch, the molten pool, and the weld in real time based on online sensing and analysis of welding process signals, and implements closed-loop correction of the welding trajectory.

[0060] Step S104: Obtain the arc tracking current signal within the reference welding cycle as the reference current signal.

[0061] The reference welding cycle can be a preset start tracking cycle. When the welding torch is moved to the preset start tracking cycle, the arc tracking reference signal within the current of the preset start tracking cycle is calculated.

[0062] The arc tracking current signal within the reference welding cycle can be the arc tracking current signal within the pre-set starting tracking cycle. In subsequent arc tracking processes, the reference current signal within the reference welding cycle is used as the tracking reference.

[0063] Optionally, when the welding torch is moved to the preset start tracking cycle, i.e. the reference welding cycle, the controller of the six-axis industrial robot acquires the arc tracking current signal within that cycle as the reference current signal for the subsequent arc tracking process.

[0064] For example, if the reference welding cycle is set to the Nth oscillation welding cycle, then when the oscillation welding reaches the Nth oscillation welding cycle, the arc tracking current signal collected in the Nth oscillation welding cycle will be used as the reference current signal, where N is a positive integer.

[0065] Step S106: Obtain the current arc tracking current signal within the current welding cycle; the current welding cycle is any welding cycle after the reference welding cycle.

[0066] The current welding cycle can be any welding cycle after the reference welding cycle.

[0067] The current arc tracking current signal can be an arc tracking current signal acquired in real time within any welding cycle after the reference welding cycle.

[0068] Optionally, after acquiring the reference current signal, the controller of the six-axis industrial robot acquires the current arc tracking current signal within the current welding cycle.

[0069] Step S108: Determine the current offset information based on the current arc tracking current signal and the reference current signal.

[0070] Among them, the current offset information can be information that characterizes the current offset, such as the current difference component, the average current difference component, etc. The current difference component is the difference between the current difference in the current welding cycle and the current difference in the reference welding cycle, which can characterize the left and right deviation of the oscillating welding coordinate system. The average current difference component is the difference between the average current value in the current welding cycle and the average current value in the reference welding cycle, which can characterize the up and down deviation of the oscillating welding coordinate system.

[0071] Optionally, the controller of the six-axis industrial robot determines the current offset information based on the current arc tracking current signal of the current welding cycle and the reference current signal of the reference welding cycle.

[0072] In step S110, when the current offset information indicates that the oscillating welding coordinate system has shifted, a new control command is generated based on the current offset information and sent to the welding torch. The oscillating welding coordinate system has the welding torch as the origin, the weld direction of the workpiece to be welded as the horizontal axis, the oscillation direction of the welding torch as the vertical axis, and the opposite direction of the welding torch as the vertical axis. The new control command is used to instruct the welding torch to adjust the position of the oscillating welding coordinate system so that the current generated by welding continuously tracks the reference current signal, thereby achieving weld tracking.

[0073] The oscillating welding coordinate system has the welding torch as the origin. During oscillating welding, the main oscillating welding direction (i.e., along the weld seam direction of the workpiece to be welded) is the horizontal axis (i.e., the x-axis), the oscillation direction of the welding torch is the vertical axis (i.e., the y-axis), and the opposite direction of the welding torch is the vertical axis (i.e., the z-axis).

[0074] Among them, the new control command can be a compensation command for compensating for welding torch offset, so that the welding torch changes the oscillation welding coordinate system under the instruction of the new control command, so that the oscillation welding coordinate system returns to the weld center line of the workpiece to be welded, and the welding current continuously tracks the reference current signal to achieve weld tracking.

[0075] Optionally, when the current offset information indicates that the welding coordinate system has shifted, the controller of the six-axis industrial robot generates new control commands based on the current offset information and sends the new control commands to the welding torch. The welding torch changes the welding coordinate system according to the new control commands, so that the welding coordinate system returns to the weld centerline of the workpiece to be welded, and the welding current continuously tracks the reference current signal to achieve weld tracking.

[0076] In the aforementioned arc tracking method based on end-dwelling oscillation welding, control commands are sent to the welding torch. These commands instruct the torch to perform oscillation welding on the weld seam of the workpiece to be welded according to a preset oscillation welding method, and to pause for a preset duration when moving to either end of the torch's oscillation direction. The arc tracking current signal within a reference welding cycle is acquired as a reference current signal. The current arc tracking current signal within the current welding cycle is acquired; the current welding cycle is any welding cycle following the reference welding cycle. Current offset information is determined based on the current arc tracking current signal and the reference current signal. If the current offset information indicates a shift in the oscillation welding coordinate system, a new control command is generated based on the current offset information and sent to the welding torch. The oscillation welding coordinate system has the welding torch as its origin, the weld seam direction of the workpiece to be welded as its horizontal axis, and the oscillation direction of the welding torch as its horizontal axis. The direction is the vertical axis, and the opposite direction of the welding torch is the vertical axis. The new control commands are used to instruct the welding torch to adjust the position of the oscillating welding coordinate system so that the welding current continuously tracks the reference current signal, thereby achieving weld tracking. In this way, the addition of the end-stop arc tracking method can reduce the vibration and spatter caused by the large impact when the welding torch swings to the inflection point, improve the welding process effect, and have a stronger generalization ability in application scenarios with large welds and excessively long welding wires. Furthermore, it can adaptively extract the reference current signal according to the current difference caused by different welding workpiece thicknesses and different welding currents, effectively reducing the testing environment required before welding and increasing welding efficiency. At the same time, it can complete the deviation detection based solely on the welding current signal without relying on external optical sensors and arc sensors, making it easy to quickly deploy on robots or welding applications.

[0077] In the oscillating welding coordinate system, the Z-shaped oscillating welding expression for the (n+1)th (n=0, 1, 2, 3, ...) oscillating welding cycle, including the end dwell time, is:

[0078]

[0079] Where f is the set wave soldering frequency, t s T is the preset end dwell time (corresponding to the preset duration), A is the set welding amplitude, which can be changed according to specific welding requirements. w The actual sloshing welding cycle is expressed as:

[0080]

[0081] In actual welding, observation of the original current signal during the sway welding process reveals that the current waveform changes after adding an end dwell time. Within the cycle, the two-peak current waveform without end dwell time changes to a three-peak current waveform. The waveform after low-pass filtering to remove noise is as follows: Figure 2As shown. For current-based arc tracking, extracting the periodic current corresponding to the periodic oscillation welding is crucial. This invention employs the FFT filtering method, which extracts the frequency signal with the same expression as the oscillation welding by performing a discrete Fourier transform on the current value within the oscillation welding cycle. Then, an inverse transform is performed to obtain a current signal suitable for arc tracking. More detailed implementation methods can be found in the description of the following embodiments.

[0082] In an exemplary embodiment, determining current offset information based on the current arc tracking current signal and the reference current signal includes: determining the current current difference and the current average current value within the current welding cycle based on the current arc tracking current signal; and determining the reference current difference and the reference average current value based on the reference current signal; subtracting the reference current difference from the current current difference as the current difference component corresponding to the current welding cycle; and subtracting the reference average current value from the current average current value as the average current difference component corresponding to the current welding cycle; and using the current difference component and the average current difference component as current offset information.

[0083] The current current difference within the current welding cycle can be the difference between the maximum and minimum current values ​​in the current arc tracking current signal within the current welding cycle, and can be denoted as ΔI. (k) , k represents the cycle order of the current welding cycle. Under the baseline condition of no lateral displacement of the welding torch, ΔI is basically stable as a constant (denoted as ΔI0).

[0084] Wherein, the current average current value within the current welding cycle can be the average current value corresponding to the current arc tracking current signal within the current welding cycle, and can be denoted as: Where n is the current sequence of a single cycle. Under the reference condition of no longitudinal offset of the welding torch, It is basically stable and constant (denoted as ). ).

[0085] The reference current difference can be the difference between the maximum and minimum current values ​​in the reference current signal within the reference welding cycle, and can be denoted as ΔI0.

[0086] The reference average current value can be the average current value corresponding to the reference current signal within the reference welding cycle, and can be denoted as:

[0087] In practical applications, when the thickness of the workpieces to be welded is different, the reference current difference ΔI0 and the reference average current value may differ.

[0088] In actual welding, the welding current waveform is unstable during the arc initiation stage. Therefore, arc tracking is not performed during the arc initiation stage. When the welding cycle passes the set start-tracking cycle, the current difference collected during that cycle is used as the reference current difference ΔI0, and the average current value is used as the reference average current value.

[0089] The current difference component corresponding to the current welding cycle can be the difference between the current current difference in the current welding cycle and the reference current difference in the reference welding cycle, which can be denoted as δ. (k) δ (k) =ΔI (k) -ΔI0.

[0090] It should be noted that the offset of the vertical axis (y-axis) of the tack welding coordinate system in the current welding cycle needs to be determined based on the current current difference ΔI within the current welding cycle. (k) The judgment is based on the difference between the reference current difference ΔI0 and the current difference component δ corresponding to the current welding cycle. (k) The offset of the vertical axis (y-axis) of the oscillating welding coordinate system in the current welding cycle is determined.

[0091] For example, when the oscillating welding coordinate system is tilted to the right, the end peaks increase or the central valley rises more weakly, ΔI (k) As it increases, therefore δ (k) >0; When the oscillating welding coordinate system deviates to the left, ΔI (k) Decrease, therefore δ (k) <0. Therefore, the orientation rule can be given using a single threshold or a small threshold τ with hysteresis: if Determine right deviation; if Determine left deviation; if Approximately unbiased.

[0092] In other words, if the absolute value of the current difference component corresponding to the current welding cycle is less than or equal to a preset first threshold τ, it is determined that the oscillating welding coordinate system has not shifted left or right within the current welding cycle; if the absolute value of the current difference component corresponding to the current welding cycle is greater than the preset first threshold τ and the current difference component is positive, it is determined that the oscillating welding coordinate system has shifted right within the current welding cycle; if the absolute value of the current difference component corresponding to the current welding cycle is greater than the preset first threshold τ and the current difference component is negative, it is determined that the oscillating welding coordinate system has shifted left within the current welding cycle.

[0093] The difference component of the average current value corresponding to the current welding cycle can be the difference between the current average current value of the current welding cycle and the reference average current value of the reference welding cycle, which can be denoted as:

[0094] It should be noted that the offset of the vertical axis (z-axis) of the tack welding coordinate system in the current welding cycle needs to be determined based on the current average current value within the current welding cycle. Compared with the reference average current value during the reference welding cycle The difference between the two is used for judgment, that is, based on the difference component ρ of the average current value corresponding to the current welding cycle. (k) The offset of the vertical axis (z-axis) of the oscillating welding coordinate system in the current welding cycle is determined.

[0095] For example, when the welding coordinate system shifts upward (z-direction offset), the distance between the welding torch and the weld increases, and the wire elongation increases. As it decreases, therefore ρ (k) <0; When the welding coordinate system deflects downward (shifts in the opposite direction of the z-direction), the distance between the welding torch and the weld decreases, and the wire elongation decreases. As it increases, therefore ρ (k) >0. Therefore, the orientation rule can be given using a single threshold or a small threshold σ with hysteresis: if Determine if it is biased upwards; if Determine downward deviation; if Approximately unbiased.

[0096] In other words, if the absolute value of the average current difference component corresponding to the current welding cycle is less than or equal to the preset second threshold, it is determined that the oscillating welding coordinate system has not shifted vertically within the current welding cycle; if the absolute value of the average current difference component corresponding to the current welding cycle is greater than the preset second threshold and the average current difference component is negative, it is determined that the oscillating welding coordinate system has shifted upward within the current welding cycle; if the absolute value of the average current difference component corresponding to the current welding cycle is greater than the preset second threshold and the average current difference component is positive, it is determined that the oscillating welding coordinate system has shifted downward within the current welding cycle.

[0097] Optionally, the controller of the six-axis industrial robot determines the current current difference and the current average current value within the current welding cycle based on the current arc tracking current signal. The controller also determines the reference current difference and the reference average current value based on the reference current signal. The controller subtracts the reference current difference from the current current difference as the current difference component corresponding to the current welding cycle. Furthermore, the controller subtracts the reference average current value from the current average current value as the average current difference component corresponding to the current welding cycle. The controller uses the current difference component and the average current difference component as current offset information to determine the offset of the welding coordinate system.

[0098] In this embodiment, the current current difference and the current average current value within the current welding cycle are determined based on the current arc tracking current signal, and the reference current difference and the reference average current value are determined based on the reference current signal. The result of subtracting the reference current difference from the current current difference is taken as the current difference component corresponding to the current welding cycle, and the result of subtracting the reference average current value from the current average current value is taken as the average current difference component corresponding to the current welding cycle. The current difference component and the average current difference component are used as current offset information. In this way, more effective current offset information can be extracted, which is beneficial for the subsequent correction of the oscillating welding coordinate system and achieves more accurate weld tracking.

[0099] After incorporating the end dwell time, the current waveform during the oscillating welding cycle changes from a two-peak current waveform to a three-peak current waveform. Traditional weld deviation extraction methods are not applicable to this three-peak current waveform. The measured three-peak current waveform exhibits an "end peak – center valley" structure within each oscillating welding cycle, and the maximum and minimum values ​​are stably separated by half a cycle in time. Based on this prior structure, the next embodiment provides a method for accurately extracting the current difference along the longitudinal axis (y-axis) of the oscillating welding coordinate system during the welding cycle. Please refer to the detailed description of the next embodiment.

[0100] In an exemplary embodiment, determining the current current difference within the current welding cycle based on the current arc tracking current signal includes: searching for local maxima of the arc tracking current within a preset range around the start point of the current welding cycle, and searching for local minima of the arc tracking current within a preset range around the midpoint of the current welding cycle; and using the result of subtracting the local minima of the arc tracking current from the local maxima as the current current difference.

[0101] The starting point of the current welding cycle can be marked as: k represents the cycle order of the current welding cycle. It represents the starting point of the k-th welding cycle.

[0102] The preset range around the starting point of the current welding cycle can be 5%T ahead of the starting point of the current welding cycle. w The range.

[0103] Among them, the local maximum value of the arc tracking current can be the local maximum value obtained by searching the current arc tracking current signal at the "end peak" in the current welding cycle.

[0104] The midpoint of the current welding cycle can be marked as follows:

[0105] The preset range around the midpoint of the current welding cycle can be 5%T in front of the midpoint of the current welding cycle. w The range.

[0106] Among them, the local minimum value of the arc tracking current can be the local minimum value obtained by searching the current arc tracking current signal at the "central valley" in the current welding cycle.

[0107] Optionally, two time markers, spaced half a cycle apart, are set in each welding cycle. Phase calibration is used to align these markers locally to the actual extreme point of that welding cycle, ensuring that the comparison focuses on the "end peak" and "center valley" of the same cycle, representing half-cycles of each other. When the current welding cycle is the k-th welding cycle, the controller of the six-axis industrial robot takes the cycle start point marker of the k-th welding cycle as... Then another mark is placed Then, within their respective small time windows (e.g., taking 5% T before the marker), w Search for local extrema within the range ( ) to obtain the aligned extremum moment. and And read the corresponding current Therefore, the current current difference value for the current welding cycle is defined as the result of subtracting the local minimum value of the arc tracking current from the local maximum value of the arc tracking current, i.e.

[0108] In this embodiment, by searching for local maxima of the arc tracking current within a preset range around the starting point of the current welding cycle, and searching for local minima of the arc tracking current within a preset range around the midpoint of the current welding cycle, the result of subtracting the local minima of the arc tracking current from the local maxima is used as the current current difference. In this way, based on the peak-valley current difference marked by half a cycle, a more accurate current difference can be determined for the single-cycle three-peak current pattern generated by the addition of end dwell time, which is beneficial for accurately judging the left and right deviation of the tumbling welding coordinate system in the subsequent process.

[0109] In an exemplary embodiment, generating a new control command based on current offset information includes: inputting the current difference component into a left-right offset determination model to obtain the vertical axis offset for the oscillating welding coordinate system; and inputting the average current difference component into an up-down offset determination model to obtain the vertical axis offset for the oscillating welding coordinate system. The left-right offset determination model is pre-fitted based on a left-right offset current difference dataset, which includes multiple sets of current difference values ​​corresponding to left or right offset of the oscillating welding coordinate system. The up-down offset determination model is pre-fitted based on an up-down offset current difference dataset, which includes multiple sets of current difference values ​​corresponding to up or down offset of the oscillating welding coordinate system. A control quantity is determined based on the vertical axis offset and the vertical axis offset. The control quantity is used to compensate for welding torch offset. A new control command is generated based on the control quantity.

[0110] The left and right offset determination model can refer to the offset calculation model for judging left and right offsets. It is obtained by fitting the left and right offset current difference dataset using the least squares method. That is, the left and right offset current difference dataset is collected, outlier data points are removed, and the relationship between the offset and the current difference component is fitted into a first-order linear model, which can be expressed as follows: Where, ε y For the fitting error, δ (k) The difference component is the current difference. This is the y-axis offset.

[0111] The left and right offset current difference dataset includes multiple sets of current difference values ​​with specific offsets, such as multiple sets of current difference values ​​corresponding to left or right offsets in the oscillating welding coordinate system.

[0112] The upper and lower offset determination model is pre-fitted based on the upper and lower offset current difference dataset. This model is obtained by fitting the dataset using the least squares method, which involves collecting the upper and lower offset current difference dataset, removing outlier data points, and fitting the relationship between the offset and the average current difference component into a first-order linear model, which can be expressed as follows: Where, ε z For the fitting error, ρ (k) The difference component of the average current value This is the z-axis offset.

[0113] The upper and lower offset current difference dataset includes multiple sets of current difference values ​​with specific offsets, such as multiple sets of current difference values ​​corresponding to the upper or lower offset of the oscillating welding coordinate system.

[0114] The vertical axis offset can refer to the magnitude of the offset of the y-axis in the swivel welding coordinate system.

[0115] The vertical axis offset can refer to the magnitude of the offset of the z-axis in the oscillating welding coordinate system.

[0116] Among them, the control quantity can be the range of adjustment required for the welding torch.

[0117] Optionally, after arc tracking begins, the controller of the six-axis industrial robot calculates the current difference component δ in each cycle. (k) The difference component ρ between the average current value and the average current value (k) After acquiring the current difference component and the average current difference component of the current welding cycle, the controller of the six-axis industrial robot inputs the current difference component into the left-right offset determination model to obtain the vertical axis offset relative to the welding coordinate system. It also inputs the average current difference component into the up-down offset determination model to obtain the vertical axis offset relative to the welding coordinate system. Then, based on the vertical axis offset and the vertical axis offset, the offset to be compensated is input into the PID controller to output the control quantity for compensating the welding torch offset. The controller determines the control quantity and sends a compensation command (i.e., a new control command) to the welding torch to reduce or eliminate the offset and achieve the tracking effect.

[0118] In this embodiment, the vertical axis offset of the oscillating welding coordinate system is obtained by inputting the current difference component into the left-right offset determination model, and the vertical axis offset of the oscillating welding coordinate system is obtained by inputting the average current difference component into the up-down offset determination model. The left-right offset determination model is pre-fitted based on the left-right offset current difference dataset, which includes multiple sets of current difference values ​​corresponding to left or right offset of the oscillating welding coordinate system. The up-down offset determination model is pre-fitted based on the up-down offset current difference dataset, which includes multiple sets of current difference values ​​corresponding to up or down offset of the oscillating welding coordinate system. A control quantity is determined based on the vertical axis offset and the vertical axis offset. The control quantity is used to compensate for the welding torch offset. A new control command is generated based on the control quantity. In this way, the offset of the oscillating welding coordinate system can be accurately determined, thereby enabling precise adjustment of the welding torch position and improving the welding effect.

[0119] In an exemplary embodiment, acquiring the current arc tracking current signal within the current welding cycle includes: acquiring the initial arc tracking current signal within the current welding cycle; filtering the initial arc tracking current signal to obtain a filtered signal; and performing an inverse transformation on the filtered signal to obtain the current arc tracking current signal.

[0120] The initial arc tracking current signal can be the original arc tracking current signal acquired without preprocessing.

[0121] The filtered signal can refer to the signal obtained after performing a fast Fourier transform on the initial arc tracking current signal.

[0122] The current arc tracking current signal is the frequency signal extracted from the filtered signal after performing a discrete Fourier transform, which is the same as the expression for the sway welding.

[0123] Optionally, the controller acquires the initial arc tracking current signal within the current welding cycle, performs a fast Fourier transform on the initial arc tracking current signal to obtain a frequency signal with the same frequency as the sway welding expression, i.e., a filtered current signal, and then performs an inverse transform on the filtered current signal to obtain a current signal suitable for arc tracking, i.e., the current arc tracking current signal, the waveform of which is as follows: Figure 3 As shown. In practical applications, the expression for the discrete Fourier transform used is:

[0124]

[0125] Where X[k] is the output discrete spectrum sequence, k is the index of the frequency domain component (frequency point), and x[n] is the input signal sequence.

[0126] In this embodiment, the initial arc tracking current signal within the current welding cycle is acquired; the initial arc tracking current signal is filtered to obtain a filtered signal; the filtered signal is then inversely transformed to obtain the current arc tracking current signal. In this way, the adaptive capability of the frequency selection reconstruction of the discrete Fourier transform can be utilized to adaptively extract characteristic frequencies for different set welding methods and welding currents, and reconstruct the acquired current signal into the signal required for arc tracking.

[0127] For the convenience of those skilled in the art, Figure 4This document provides an exemplary flowchart of a welding arc tracking method based on end-dwelling. In practical operation, the method first requires teaching the start and end points of the workpiece to be welded, ensuring there are no weld breaks between these points to prevent the welding process from failing to identify the weld. Attention must be paid to the orientation of the start and end points to prevent torch collisions. Then, after the welding torch moves to the taught start point, arc tracking begins. The welding torch performs Z-shaped oscillation welding according to control commands, pausing for 0.1 seconds at both ends. Simultaneously, the current signal generated during welding is acquired, preprocessed, and then filtered using FFT (which maps the discrete-time domain signal to the frequency domain via Fast Fourier Transform (FFT), filtering out unwanted frequency components in the frequency domain). After inverse IFFT (Inverse IFFT) to return to the time domain, the desired signal is reconstructed (approximately achieving ideal frequency band selection and suppression with lower computational cost). When the welding reaches the set start tracking cycle, the arc tracking reference current is calculated, and the subsequent tracking process uses this reference current as the tracking reference. Then, when the welding coordinate system shifts, the collected current will deviate from the reference current value. The shifted current value is processed by the adjusted current compensation model (i.e., the shift calculation model) to output a compensation value. The compensation value is input into the PID controller to output the control quantity to compensate for the welding torch shift. The welding torch receives the control command to change the welding coordinate system, so that the welding coordinate system returns to the weld centerline, that is, the welding current continuously tracks the reference current to achieve weld tracking.

[0128] This application presents a method for arc tracking in oscillating welding based on end-dwelling. Under conditions where the welding torch performs Z-shaped oscillating welding with predetermined dwell times at the left and right ends, it can acquire welding current in real time. For single-cycle three-peak current patterns, it performs cycle extraction, extreme value alignment, and deviation determination, and sends the compensation amount to the controller to return the oscillating welding coordinate system to the weld centerline. In Z-shaped oscillating welding with end-dwelling times, two time markers spaced half a cycle apart are placed in each oscillating welding cycle. Within the local time window of each marker, the peak current at the end and the valley current at the center of that cycle are aligned. The current difference is calculated and compared with the reference difference to determine left and right deviations, achieving cycle-level offset direction determination. FFT filtering can be used to process the current signal in real time. In DFT processing, only the frequency component (and symmetrical component) with the same oscillating welding frequency is retained, and then an inverse transform is performed to obtain the current sequence used for criterion calculation. Under different plate thicknesses and set currents, the reference current difference and reference average current may change slightly. Adaptive extraction of the reference current difference and reference average current after arc initiation ensures arc tracking effectiveness under different welding environments and reduces unnecessary current testing procedures.

[0129] Compared with the prior art, the advantages of the technical solution of this application are as follows:

[0130] 1) Introducing end-dwelling at the process level allows for the development of a combined criterion on the signal side for the resulting three-peak current waveform: "FFT frequency selection and reconstruction at the same frequency as the sway welding" and "peak-valley current difference marked by half a cycle." This means that only the current component consistent with the sway welding frequency is retained, and then aligned to the true extreme value of the current cycle at two points half a cycle apart. The y-axis direction is determined by comparing the current current difference with the reference current difference, and the z-axis direction is determined by comparing the current average current value with the reference average current value. This process is inherently robust to the phase-time distortion and three-peak shape caused by end-dwelling, avoiding the failure or misjudgment of traditional methods in sway scenarios. Furthermore, the calculation can be completed within one sway cycle, satisfying real-time closed-loop requirements. The FFT filtering frequency selection and reconstruction also has good adaptive capabilities, adaptively extracting characteristic frequencies for different sway welding methods and welding currents, reconstructing the acquired current signal into the signal required for arc tracking.

[0131] 2) It does not rely on external optical sensors and arc sensors. It can complete deviation detection and linear least squares calibration mapping using only welding current. It has fewer parameters, is simple to implement, and is easy to deploy quickly on existing robots / welding machines.

[0132] 3) The end-point dwell significantly improves the sidewall line energy and fusion stability, achieving both "improved forming quality" and "improved tracking stability", making it more applicable to engineering.

[0133] In another embodiment, such as Figure 5 As shown, a method for tracking the welding arc based on end-dwelling is provided. This method is applied to the controller of a six-axis industrial robot and is illustrated with the following steps:

[0134] Step S502: Send a control command to the welding torch; the control command is used to instruct the welding torch to perform sway welding on the weld seam of the workpiece to be welded in a preset sway welding manner, and to stay for a preset time when it moves to both ends of the swaying direction of the welding torch.

[0135] Step S504: Obtain the arc tracking current signal within the reference welding cycle as the reference current signal.

[0136] Step S506: Obtain the current arc tracking current signal within the current welding cycle; the current welding cycle is any welding cycle after the reference welding cycle.

[0137] Step S508: Based on the current arc tracking current signal, determine the current current difference and the current average current value within the current welding cycle, and based on the reference current signal, determine the reference current difference and the reference average current value.

[0138] Step S510: Subtract the reference current difference from the current current difference as the current difference component corresponding to the current welding cycle, and subtract the reference average current value from the current average current value as the average current difference component corresponding to the current welding cycle.

[0139] Step S512: Use the current difference component and the average current difference component as current offset information.

[0140] Step S514: When the current offset information indicates that the oscillating welding coordinate system has shifted, the current difference component is input into the left-right offset determination model to obtain the vertical axis offset of the oscillating welding coordinate system. The average current difference component is input into the up-down offset determination model to obtain the vertical axis offset of the oscillating welding coordinate system. The left-right offset determination model is pre-fitted based on the left-right offset current difference dataset. The left-right offset current difference dataset includes multiple sets of current difference values ​​corresponding to left or right offset of the oscillating welding coordinate system. The up-down offset determination model is pre-fitted based on the up-down offset current difference dataset. The up-down offset current difference dataset includes multiple sets of current difference values ​​corresponding to up or down offset of the oscillating welding coordinate system. The oscillating welding coordinate system has the welding torch as the origin, the weld direction of the workpiece to be welded as the horizontal axis, the oscillation direction of the welding torch as the vertical axis, and the opposite direction of the welding torch as the vertical axis.

[0141] Step S516: Determine the control quantity based on the vertical axis offset and the vertical axis offset; the control quantity is used to compensate for the welding torch offset.

[0142] Step S518: Based on the control quantity, generate a new control command and send the new control command to the welding torch; the new control command is used to instruct the welding torch to adjust the position of the oscillating welding coordinate system so that the welding current continuously tracks the reference current signal, thereby achieving weld tracking.

[0143] It should be noted that the specific limitations of the above steps can be found in the above description of the specific limitations of a tumbling arc tracking method based on end-dwelling.

[0144] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0145] Based on the same inventive concept, this application also provides an end-stop-based oscillating arc tracking device for implementing the above-described end-stop-based oscillating arc tracking method. The solution provided by this device is similar to the solution described in the above method; therefore, the specific limitations of one or more end-stop-based oscillating arc tracking device embodiments provided below can be found in the above-described limitations of the end-stop-based oscillating arc tracking method, and will not be repeated here.

[0146] In one exemplary embodiment, such as Figure 6 As shown, a poling arc tracking device based on end-dwelling is provided, comprising: a sending module 602, a first acquisition module 604, a second acquisition module 606, a determining module 608, and a generating module 610, wherein:

[0147] The sending module 602 is used to send control commands to the welding torch; the control commands are used to instruct the welding torch to perform oscillating welding on the weld seam of the workpiece to be welded according to a preset oscillating welding method, and to stay for a preset duration when it moves to both ends of the oscillation direction of the welding torch;

[0148] The first acquisition module 604 is used to acquire the arc tracking current signal within the reference welding cycle as a reference current signal.

[0149] The second acquisition module 606 is used to acquire the current arc tracking current signal within the current welding cycle; the current welding cycle is any welding cycle after the reference welding cycle.

[0150] The determining module 608 is used to determine current offset information based on the current arc tracking current signal and the reference current signal;

[0151] The generation module 610 is used to generate a new control command based on the current offset information when the current offset information indicates that the oscillating welding coordinate system has shifted, and send the new control command to the welding torch. The oscillating welding coordinate system has the welding torch as the origin, the weld direction of the workpiece to be welded as the horizontal axis, the oscillation direction of the welding torch as the vertical axis, and the opposite direction of the welding torch as the vertical axis. The new control command is used to instruct the welding torch to adjust the position of the oscillating welding coordinate system so that the welding current continuously tracks the reference current signal, thereby achieving weld tracking.

[0152] In one embodiment, the determining module 608 is specifically configured to determine the current current difference and the current average current value within the current welding cycle based on the current arc tracking current signal, and to determine the reference current difference and the reference average current value based on the reference current signal; to use the result of subtracting the reference current difference from the current current difference as the current difference component corresponding to the current welding cycle, and to use the result of subtracting the reference average current value from the current average current value as the average current difference component corresponding to the current welding cycle; and to use the current difference component and the average current difference component as current offset information.

[0153] In one embodiment, the determining module 608 is specifically used to search for a local maximum value of the arc tracking current within a preset range around the starting point of the current welding cycle, and to search for a local minimum value of the arc tracking current within a preset range around the midpoint of the current welding cycle; the result obtained by subtracting the local minimum value of the arc tracking current from the local maximum value is used as the current current difference value.

[0154] In one embodiment, the generation module 610 is specifically used to input the current difference component to the left-right offset determination model to obtain the vertical axis offset for the oscillating welding coordinate system, and to input the average current difference component to the up-down offset determination model to obtain the vertical axis offset for the oscillating welding coordinate system; the left-right offset determination model is pre-fitted based on the left-right offset current difference dataset; the left-right offset current difference dataset includes multiple sets of current difference values ​​corresponding to the left or right offset of the oscillating welding coordinate system; the up-down offset determination model is pre-fitted based on the up-down offset current difference dataset; the up-down offset current difference dataset includes multiple sets of current difference values ​​corresponding to the up or down offset of the oscillating welding coordinate system; a control quantity is determined based on the vertical axis offset and the vertical axis offset; the control quantity is used to compensate for the welding torch offset; and a new control command is generated based on the control quantity.

[0155] In one embodiment, the second acquisition module 606 is specifically used to acquire the initial arc tracking current signal in the current welding cycle; filter the initial arc tracking current signal to obtain a filtered signal; and perform an inverse transformation on the filtered signal to obtain the current arc tracking current signal.

[0156] Each module in the aforementioned end-dwelling-based arc tracking device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device, or stored in the computer device's memory as software, so that the processor can call and execute the corresponding operations of each module.

[0157] In one exemplary embodiment, a six-axis industrial robot for welding is provided, including a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps of the above-described end-dwell-based oscillating welding arc tracking method. The six-axis industrial robot should have an oscillating component and a welding torch.

[0158] In one exemplary embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 7 As shown, the computer device includes a processor, memory, input / output (I / O) interfaces, and a communication interface. The processor, memory, and I / O interfaces are connected via a system bus, and the communication interface is also connected to the system bus via the I / O interfaces. The processor provides computational and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides the environment for the operating system and computer programs in the non-volatile storage media to run. The database stores end-dwell-based arc tracking data for welding. The I / O interfaces allow the processor to exchange information with external devices. The communication interface allows communication with external terminals via a network connection. When executed by the processor, the computer program implements an end-dwell-based arc tracking method for welding.

[0159] Those skilled in the art will understand that Figure 7 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0160] In one embodiment, a computer device is provided, including a memory and a processor. The memory stores a computer program, which, when executed by the processor, causes the processor to perform the steps of the aforementioned end-dwell-based oscillating arc tracking method. The steps of the end-dwell-based oscillating arc tracking method described here can be steps from one of the end-dwell-based oscillating arc tracking methods in the various embodiments described above.

[0161] In one embodiment, a computer-readable storage medium is provided storing a computer program that, when executed by a processor, causes the processor to perform the steps of the aforementioned end-dwell-based oscillating arc tracking method. The steps of the end-dwell-based oscillating arc tracking method may be steps from one of the end-dwell-based oscillating arc tracking methods described in the various embodiments above.

[0162] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, causes the processor to perform the steps of the aforementioned end-dwell-based oscillating arc tracking method. The steps of the end-dwell-based oscillating arc tracking method described above can be steps from one of the end-dwell-based oscillating arc tracking methods in the various embodiments described above.

[0163] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0164] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0165] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A method for tracking the oscillating welding arc based on end-dwelling, characterized in that, The method includes: Send a control command to the welding torch; the control command is used to instruct the welding torch to perform oscillating welding on the weld seam of the workpiece to be welded according to a preset oscillating welding method, and to stay for a preset duration when it moves to both ends of the oscillation direction of the welding torch; The arc tracking current signal within the reference welding cycle is acquired and used as the reference current signal; Obtain the current arc tracking current signal within the current welding cycle; the current welding cycle is any welding cycle after the reference welding cycle; Based on the current arc tracking current signal and the reference current signal, determine the current offset information; When the current offset information indicates that the oscillating welding coordinate system has shifted, a new control command is generated based on the current offset information and sent to the welding torch. The oscillating welding coordinate system has the welding torch as the origin, the weld direction of the workpiece to be welded as the horizontal axis, the oscillation direction of the welding torch as the vertical axis, and the opposite direction of the welding torch as the vertical axis. The new control command is used to instruct the welding torch to adjust the position of the oscillating welding coordinate system so that the welding current continuously tracks the reference current signal, thereby achieving weld tracking.

2. The method according to claim 1, characterized in that, The step of determining the current offset information based on the current arc tracking current signal and the reference current signal includes: Based on the current arc tracking current signal, determine the current current difference and the current average current value within the current welding cycle, and based on the reference current signal, determine the reference current difference and the reference average current value. The result of subtracting the reference current difference from the current current difference is taken as the current difference component corresponding to the current welding cycle, and the result of subtracting the reference average current value from the current average current value is taken as the average current difference component corresponding to the current welding cycle. The current difference component and the average current difference component are used as the current offset information.

3. The method according to claim 2, characterized in that, Determining the current current difference within the current welding cycle based on the current arc tracking current signal includes: Within a preset range around the start point of the current welding cycle, search for local maxima of the arc tracking current, and within a preset range around the midpoint of the current welding cycle, search for local minima of the arc tracking current. The result of subtracting the local minimum value of the arc tracking current from the local maximum value of the arc tracking current is taken as the current difference value.

4. The method according to claim 2, characterized in that, The step of generating new control commands based on the current offset information includes: The current difference component is input into the left-right offset determination model to obtain the vertical axis offset of the oscillating welding coordinate system. The average current difference component is input into the up-down offset determination model to obtain the vertical axis offset of the oscillating welding coordinate system. The left-right offset determination model is pre-fitted based on the left-right offset current difference dataset, which includes multiple sets of current difference values ​​corresponding to left or right offset of the oscillating welding coordinate system. The up-down offset determination model is pre-fitted based on the up-down offset current difference dataset, which includes multiple sets of current difference values ​​corresponding to up or down offset of the oscillating welding coordinate system. The control quantity is determined based on the vertical axis offset and the vertical axis offset; the control quantity is used to compensate for the welding torch offset. The new control command is generated based on the control quantity.

5. The method according to claim 1, characterized in that, The step of acquiring the current arc tracking current signal within the current welding cycle includes: Acquire the initial arc tracking current signal within the current welding cycle; The initial arc tracking current signal is filtered to obtain the filtered signal; The filtered signal is inversely transformed to obtain the current arc tracking current signal.

6. A tumbling arc tracking device based on end-dwelling, characterized in that, The device includes: The sending module is used to send control commands to the welding torch; the control commands are used to instruct the welding torch to perform oscillating welding on the weld seam of the workpiece to be welded according to a preset oscillating welding method, and to stay for a preset duration when it moves to both ends of the oscillation direction of the welding torch; The first acquisition module is used to acquire the arc tracking current signal within the reference welding cycle as a reference current signal; The second acquisition module is used to acquire the current arc tracking current signal within the current welding cycle; the current welding cycle is any welding cycle after the reference welding cycle. The determination module is used to determine current offset information based on the current arc tracking current signal and the reference current signal; The generation module is used to generate new control commands based on the current offset information when the current offset information indicates that the oscillating welding coordinate system has shifted, and send the new control commands to the welding torch. The oscillating welding coordinate system has the welding torch as the origin, the weld direction of the workpiece to be welded as the horizontal axis, the oscillation direction of the welding torch as the vertical axis, and the opposite direction of the welding torch as the vertical axis. The new control commands are used to instruct the welding torch to adjust the position of the oscillating welding coordinate system so that the welding current continuously tracks the reference current signal, thereby achieving weld tracking.

7. A six-axis industrial robot for welding, comprising a memory and a processor, the memory storing a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 5.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 5.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 5.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 5.

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