A fillet weld arc deviation detection and tracking method based on decoupling coefficient compensation

Abstract

The application provides a fillet weld arc deviation detection and tracking method based on decoupling coefficient compensation, comprising the following steps: acquiring welding process parameters, left limit welding current, right limit welding current, transverse zero point current and expected average current under standard welding height of a welding torch; determining a decoupling coefficient based on the welding process parameters, the decoupling coefficient representing the proportion of the difference signal change amount caused by the asymmetry of the base material to the depth change amount; determining the transverse reference current after decoupling compensation based on the decoupling coefficient, the left limit welding current, the right limit welding current, the transverse zero point current and the expected average current under the standard welding height of the welding torch; and determining the transverse correction signal based on the transverse reference current after decoupling compensation. Through the implementation of the application, the transverse deviation and the depth deviation are truly decoupled in the fillet weld arc sensing, the problem of false triggering of the transverse correction action caused by the depth adjustment is avoided, and the control stability of the fillet weld arc tracking is improved.

Description

Technical Field

[0001] This invention belongs to the field of welding automation and robot intelligent control technology, specifically relating to a method for detecting and tracking arc deviation in fillet welds based on decoupling coefficient compensation. Background Technology

[0002] During automated fillet weld welding, due to workpiece clamping errors, welding thermal deformation, and weld trajectory deviation, the welding torch can easily deviate from the weld center or standard welding height, leading to welding defects such as incomplete fusion, weld beads, and burn-through. Arc sensing technology utilizes the characteristic that the welding current in gas shielded welding is inversely proportional to the distance from the welding wire tip to the base material. By detecting the changes in welding current on both sides during the torch's oscillation, it achieves real-time detection of lateral centering deviation and depth (elongation) deviation, and is currently a widely used weld tracking method in industrial welding robots.

[0003] Under the constant voltage characteristics of the welding power source, the current on both sides changes simultaneously when the welding torch height changes (depth deviation). However, due to significant differences in heat dissipation conditions, molten pool spreading behavior, and the influence of gravity on droplet transition between two perpendicular base materials (horizontal plate dissipates heat quickly and the molten pool spreads easily, while vertical plate dissipates heat slowly and the droplet is pulled downward by gravity), the decrease or increase in current on both sides is not completely equal when the depth changes. Therefore, depth deviation not only changes the average current but also causes a change in the difference between the welding currents on the left and right sides. This difference change can be misinterpreted as lateral deviation, causing the controller to generate incorrect lateral correction actions. In other words, there is cross-interference between lateral deviation and depth deviation.

[0004] In addition, the unique vertical plate geometry of fillet welds makes the differences in heat dissipation and molten pool behavior between the left and right base materials more significant than in V-groove or butt welds. In fillet welds, the base material is arranged horizontally on one side and vertically on the other. The spreading behavior of the weld pool on the vertical plate is more affected by gravity, resulting in a more pronounced disturbance of the depth deviation on the difference signal. The traditional method of using the average signal for depth detection and the difference signal for lateral detection can basically meet the requirements in V-groove butt welds, but it further aggravates the problems of mutual interference between lateral correction and height adjustment, and oscillations in the control process in vertical plate fillet welds.

[0005] In related technologies, the main focus is on detecting lateral deviation through current difference and height deviation through average value, but a systematic method to quantify and compensate for the influence of depth variation on the difference signal has not yet been proposed. There is a lack of clear solutions to this problem. Some literature discusses the influence of molten pool metal on the bevel under different welding positions and uses compensation factors for weighted processing to improve deviation identification capabilities. Other studies use the biharmonic amplitude characteristic ratio method to detect left-right deviation and the scanning space weighted integral difference method to detect height deviation. However, these methods mainly focus on feature extraction and enhancement of the deviation signal, and do not solve the problem of cross-interference between lateral and depth deviations, resulting in poor control stability of arc tracking in fillet welds. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to provide a method for detecting and tracking arc deviation in fillet welds based on decoupling coefficient compensation, so as to solve the problem of cross-interference between lateral deviation and depth deviation, and improve the control stability of arc tracking in fillet welds.

[0007] To achieve the above objectives, the present invention provides the following technical solution: According to a first aspect, the present invention provides a method for detecting and tracking arc deviation in fillet welds based on decoupling coefficient compensation, comprising: acquiring welding process parameters, the left-side limit welding current, the right-side limit welding current, the transverse zero-point current, and the expected average current at a standard welding height; determining a decoupling coefficient based on the welding process parameters, wherein the decoupling coefficient characterizes the proportion of the difference signal change caused by the asymmetry of the base material to the depth change; determining a decoupling-compensated transverse reference current based on the decoupling coefficient, the left-side limit welding current, the right-side limit welding current, the transverse zero-point current, and the expected average current at a standard welding height; and determining a transverse correction signal based on the decoupling-compensated transverse reference current, wherein the transverse correction signal is used for transverse tracking control of the weld.

[0008] According to a second aspect, the present invention provides a fillet weld arc deviation detection and tracking system based on decoupling coefficient compensation, comprising: a welding power source for providing constant voltage output; an oscillation mechanism for driving the welding torch to oscillate periodically perpendicular to the weld direction at a set amplitude; a current acquisition module for synchronously acquiring the welding current at the left oscillation limit and the right oscillation limit during the oscillation cycle; a controller configured to execute the fillet weld arc deviation detection and tracking method based on decoupling coefficient compensation described in the first aspect above, and obtain a lateral correction signal and / or a height correction signal; and an execution mechanism including a lateral drive unit and a height drive unit, which adjusts the lateral position and welding height of the welding torch relative to the root of the fillet weld in real time according to the lateral correction signal and / or the height correction signal output by the controller.

[0009] According to a third aspect, embodiments of the present invention provide a computer storage medium storing computer instructions that, when executed by a processor, implement the steps of a fillet weld arc deviation detection and tracking method based on decoupling coefficient compensation as described in the first aspect or any embodiment of the first aspect.

[0010] This embodiment provides a method for detecting and tracking arc deviation in fillet welds based on decoupling coefficient compensation. By introducing a decoupling coefficient to compensate for the lateral deviation signal, this asymmetric effect is compensated. The interference of the difference signal caused by depth change is deducted from the original lateral difference, realizing true decoupling of lateral deviation and depth deviation in fillet weld arc sensing. This avoids the problem of erroneous lateral correction action due to depth adjustment, significantly improves the control stability of fillet weld arc tracking, and reduces oscillation and overshoot during the correction process.

[0011] Other advantages, objectives, and features of the invention will be set forth in the following description and will be apparent to those skilled in the art in some respects, or may be learned by practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0012] To make the objectives, technical solutions, and beneficial effects of this invention clearer, the following figures are provided for illustration: Figure 1 This is a flowchart illustrating a specific example of a fillet weld arc deviation detection and tracking method based on decoupling coefficient compensation in this invention. Figure 2 This is a flowchart illustrating a specific example of the process for generating welding process parameters and decoupling coefficients in this invention. Figure 3 This is a flowchart illustrating a specific example of the process for generating the mapping table between welding process parameters and decoupling coefficients in this invention. Figure 4 This is a schematic diagram of a module structure of a fillet weld arc deviation detection and tracking system based on decoupling coefficient compensation in this invention. Figure 5 This is a specific example diagram of a fillet weld arc deviation detection and tracking system based on decoupling coefficient compensation according to the present invention; Figure 6 This is a schematic block diagram of a specific example of an electronic device in an embodiment of the present invention. Detailed Implementation

[0013] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0014] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can also refer to the internal connection of two components; and they can refer to a wireless connection or a wired connection. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0015] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0016] This invention provides a method for detecting and tracking arc deviation in fillet welds based on decoupling coefficient compensation, such as... Figure 1 As shown, it includes: S101, obtain welding process parameters, left limit welding current, right limit welding current, transverse zero point current and expected average current at standard welding height. S102, based on welding process parameters, determine the decoupling coefficient, which characterizes the proportion of the difference signal change caused by the asymmetry of the base material to the depth change; S103, based on the decoupling coefficient, the left limit welding current of the welding torch, the right limit welding current, the transverse zero point current, and the expected average current under the standard welding height, the transverse reference current after decoupling compensation is determined. S104 determines the lateral correction signal based on the decoupled and compensated lateral reference current. The lateral correction signal is used for weld lateral tracking control.

[0017] For example, this embodiment is applied to a fillet weld formed by two mutually perpendicular base materials in gas shielded welding. The welding torch moves along the weld direction and makes periodic oscillations perpendicular to the weld direction. The periodic oscillation is a left-right cyclic oscillation. Therefore, the left-side limit welding current and the right-side limit welding current of the welding torch are the welding currents detected when the welding torch is at the left-side oscillation limit during the oscillation cycle. and welding current at the right swing limit The left and right side currents can represent the average current obtained from multiple oscillations. Welding process parameters, including base metal thickness, welding current, and welding speed, can be preset. Lateral zero-point current. Characterizes the current under ideal conditions where the welding torch is aimed at the root of the fillet weld and the depth is the standard value. Expected average current at standard welding height The average current generated by the welding torch when it is placed at the standard welding height is also called the welding topographic current.

[0018] The range of values ​​for the decoupling coefficient is: This is used to characterize the proportion of the difference signal change caused by the asymmetry of the base material to the total depth change when the depth changes; the decoupling coefficient can be determined by looking up a pre-established mapping table of welding process parameters and decoupling coefficients using welding process parameters as index items, that is, the decoupling coefficient... A mapping table can be pre-calibrated and established based on different welding process parameters, and the corresponding parameters can be automatically selected under different working conditions. It has good process adaptability.

[0019] Next, based on the decoupling coefficient The left-side limit welding current of the welding torch Right-side limiting welding current Horizontal zero-point current and the expected average current at standard welding height Determine the transverse reference current after decoupling compensation, including: based on the decoupling coefficient. The left-side limit welding current of the welding torch Right-side limiting welding current and the expected average current at standard welding height Determine the cross-interference compensation value; based on the left-side limit welding current of the welding torch. Right-side limiting welding current Horizontal zero-point current In addition to the cross-interference compensation value, the transverse reference current after decoupling compensation is determined.

[0020] Specifically, firstly, based on the left-side limiting welding current of the welding torch. Right-side limiting welding current Calculate the average value as the actual average current on both the left and right sides: ; The actual average current on the left and right sides Expected average current at standard welding height Difference to determine the average current change: ; The compensation direction is determined based on the left and right limiting welding currents of the welding torch and a predetermined sign function, where the sign function adopts... The function, specifically in the form of: ; when The value is +1 when... The value is -1, and the sign function ensures that the direction of the compensation term aligns with the direction of the original lateral deviation: when the original lateral deviation is positive, a positive value is subtracted from the compensation term; when the original lateral deviation is negative, a negative value is subtracted from the compensation term, which is equivalent to adding a positive value. This design ensures that the interference signal caused by depth offset is correctly superimposed on the current lateral deviation direction, rather than causing reverse misleading.

[0021] Finally, based on the decoupling coefficient, average current change, and compensation direction, the cross-interference compensation value is determined. , specifically: ; After obtaining the cross-interference compensation value Then, set the welding current to the left side of the welding torch to the maximum welding current. Right-side limiting welding current The difference is calculated to obtain the original lateral deviation signal. Then, the original lateral deviation signal With transverse zero-point current and cross-interference compensation value By subtracting the values, we obtain the decoupled and compensated transverse reference current. : .

[0022] Finally, based on the decoupled and compensated lateral reference current, the lateral correction signal is determined. Specifically, firstly, the direction of the welding torch's lateral centering deviation is determined according to the decoupled and compensated lateral reference current: if... The welding torch was determined to be biased towards the left side of the base material; if The welding torch was determined to be biased towards the right side of the base material; if The welding torch was found to be well centered laterally.

[0023] When the lateral reference current is greater than or less than 0, the real-time detected lateral position feedback current is compared with it to calculate the current deviation. When the deviation exceeds the threshold, a lateral correction signal is generated according to the proportional control rule. This lateral correction signal is used to drive the control quantity of the actuator. The amplitude of the correction signal is proportional to the magnitude of the current deviation, thereby driving the mechanism to move and realize lateral position correction.

[0024] This invention provides a method for detecting and tracking arc deviation in fillet welds based on decoupling coefficient compensation. This method introduces a decoupling coefficient... The lateral deviation signal is compensated to compensate for this asymmetric effect. The interference of the difference signal caused by the depth change is deducted from the original lateral difference, realizing the true decoupling of lateral deviation and depth deviation in fillet weld arc sensing. This avoids the problem of erroneous lateral correction action due to depth adjustment, significantly improves the control stability of fillet weld arc tracking, and reduces oscillation and overshoot during the correction process.

[0025] As an optional implementation, the pre-stored mapping table of welding process parameters and decoupling coefficients is determined through the following process, such as... Figure 2 As shown, it includes: S1, under specified welding process parameters, record the first left and right current difference and the average welding current of the first target side when the welding torch is welding at the standard depth position, the second left and right current difference and the average welding current of the second target side when the welding torch is welding at the target depth position, the first target side and the second target side are the same side, including the left side of the limit welding or the right side of the limit welding. S2, based on the first left and right current difference and the second left and right current difference, determine the change in the left and right current difference; S3, based on the average welding current of the first target side and the average welding current of the second target side, determine the amount of average current change caused by the depth change; S4. Based on the change in the difference between the left and right currents and the change in the average current, determine the preliminary decoupling coefficient for the corresponding depth change. S5, determine whether the stopping condition is met; if not, execute S6; if met, execute S7. S6, adjust the target depth position relative to the standard depth position upwards / downwards, and repeat steps S1-S5; S7, obtain the preliminary decoupling coefficients corresponding to the depth positions of multiple targets; S8 calculates the average of multiple preliminary decoupling coefficients, which is used as the decoupling coefficient corresponding to the specified welding process parameters.

[0026] For example, firstly, the welding torch is moved to a preset standard depth position, and welding is performed at this standard depth position. After the welding arc stabilizes and the current acquisition data is stable without fluctuations, the first left-right current difference value during the welding process is collected and recorded, and the average welding current value of the first target side is also collected and recorded. Subsequently, the welding torch is moved to a preset target depth position, keeping all welding process parameters unchanged, and steady-state welding is performed again. Similarly, the second left-right current difference value and the average welding current value of the second target side are collected and recorded. In this calibration, the target side is fixed to the same side throughout the entire process, specifically the left side of the limit welding or the right side of the limit welding. The target side is not switched throughout the process to ensure the consistency of the data acquisition benchmark.

[0027] Based on the first and second left-right current differences obtained from the data acquisition, a difference calculation is performed to determine the change in the left-right current difference. This change is used to characterize the overall change in the lateral current deviation of the welding torch after it shifts from the standard depth position to the target depth position, reflecting the degree of disturbance of the depth displacement to the lateral current balance.

[0028] Based on the average welding current values ​​of the first target side and the second target side, the average current change caused by depth variation is obtained. This change is used to characterize the inherent variation of the welding current on a single target side with the welding depth offset, and can eliminate the interference of unilateral current amplitude variation caused by depth displacement.

[0029] By correlating the change in current difference between the left and right sides with the change in average current, and matching the current coupling relationship corresponding to the depth offset, the preliminary decoupling coefficient corresponding to the current target depth position relative to the standard depth position is calculated. : ; The initial decoupling coefficient It is used to characterize the coupling relationship between welding depth and lateral current deviation under the current depth offset, and can be used to counteract the coupling interference of depth fluctuation on lateral current detection.

[0030] Then, using the standard depth position as a reference, the target depth position is adjusted upwards or downwards by a preset step size to obtain a new target depth position. Keeping the welding process parameters and the target side unchanged, steps S1 to S4 are repeated to complete a new round of data acquisition and preliminary decoupling coefficient calculation, obtaining multiple preliminary decoupling coefficients corresponding to different depth offset conditions. The above adjustment and calculation process is iterated until a preset stopping condition is met. This stopping condition can be set to completing a preset number of depth gradient calibrations or the depth offset covering the entire allowable welding depth fluctuation range of the process.

[0031] After completing all gradient depth calibrations, the arithmetic mean of the preliminary decoupling coefficients corresponding to multiple sets of different target depth positions is calculated. The final average coefficient value is then determined as the final decoupling coefficient corresponding to the current specified welding process parameters. .

[0032] After the decoupling coefficient is calibrated, it can be incorporated into the welding lateral deviation correction control system. During real-time welding, the original lateral current signal is decoupled and compensated based on the decoupling coefficient to eliminate coupling interference caused by welding depth fluctuations and obtain the decoupled lateral reference current.

[0033] Based on the above process, the following is a specific example of a pre-stored mapping table of welding process parameters and decoupling coefficients: Based on the above, the following is a specific example for reference: Taking the welding process of a certain type of welding robot on the lap fillet weld as an example, the base material is Q235 low carbon steel with a plate thickness of 6mm, the welding wire diameter is 1.2mm, the shielding gas is 80%Ar+20%CO2, the welding current is about 240A, the arc voltage is 28V, the welding speed is 45cm / min, the oscillation frequency is 2.5Hz, and the oscillation amplitude is 4mm.

[0034] The first step is to generate a decoupling coefficient mapping table, such as Figure 3 As shown, it includes: Step 1: Adjust the welding torch to the standard centering position (the torch axis is aligned with the root of the fillet weld) and the standard welding height (extend approximately 15mm). Then, initiate arc welding and stably collect the left and right current for at least 5 oscillation cycles, and calculate... (Due to the geometric asymmetry of fillet welds, this difference is usually not zero) and the expected average current at standard weld height. .

[0035] Step 2: Keeping the welding torch horizontally centered, raise the welding torch vertically by 1mm (i.e., depth deviation). (The circuit was re-welded and the current was recorded.) and For example, measured , (As the welding torch is raised, the average current decreases.)

[0036] Step 3: According to the formula Calculated .

[0037] Fourth step, repeat steps two and three, respectively. , , Three verification measurements were performed, and the average value was taken as the final decoupling coefficient. The final calibration in this example .

[0038] Next, switch to the next set of process parameters and repeat the process until all parameter combinations are tested. Then, summarize all process parameters to obtain the decoupling coefficient mapping table.

[0039] Based on this, when performing actual fillet welds under the same welding process parameters, the average current at the standard height is set. lateral zero-point current During a certain oscillation period, the following was measured. , .but: Original lateral interpolation ; Average current ; Depth offset ; Lateral deviation direction ; Substitute into the compensation formula: As can be seen, the difference between the original lateral deviation and the zero-point current is 6.5A, which is corrected to 6.31A after cross-interference compensation. Without compensation, the controller would output a slightly larger lateral correction amount; after compensation, the correction amount is slightly reduced, avoiding excessive response of false lateral deviation signals caused by depth offset.

[0040] This invention provides a method for detecting and tracking arc deviation in fillet welds based on decoupling coefficient compensation. It calibrates the coupling relationship between welding depth offset and transverse current difference. By collecting the current difference between the left and right sides at standard depth and different offset depths, and the average current on the target side, it calculates the change in current difference and the change in average current step by step, and then solves the preliminary decoupling coefficient. This method can accurately characterize the depth-transverse current coupling law caused by factors such as base material asymmetry, and can effectively eliminate the interference of welding depth fluctuation on the transverse current detection signal.

[0041] As an optional implementation, a method for detecting and tracking arc deviation in fillet welds based on decoupling coefficient compensation further includes: acquiring the depth zero-point current; determining a depth reference current based on the left-side limit welding current, the right-side limit welding current, the depth zero-point current, and the expected average current at the standard welding height; and determining a height correction signal based on the depth reference current, wherein the height correction signal is used for weld height tracking control.

[0042] For example, depth zero-point current This characterizes the current parameters collected during welding when the welding torch is operating at a standard welding depth. The depth reference current is determined by the following formula: ( ) in, The expected average current at standard welding height. For the depth zero-point current, under ideal conditions, it satisfies The depth reference current is calculated independently of the lateral compensation and is used to output the height correction signal.

[0043] The process of determining the height correction signal based on the depth reference current is the same as the process of determining the lateral correction signal based on the decoupled and compensated lateral reference current in the above embodiment, and will not be repeated here.

[0044] This invention provides a method for detecting and tracking arc deviation in fillet welds based on decoupling coefficient compensation. By relying on a precise depth reference current to generate a height correction signal, it can accurately identify weld height deviation and improve the accuracy and stability of weld height tracking control.

[0045] As an optional implementation, obtaining the left-side limit welding current and the right-side limit welding current of the welding torch includes: continuously sampling multiple current values ​​while the welding torch is stationary at the left-side swing limit position, discarding the maximum and minimum values, and taking the average value as the left-side limit welding current; and continuously sampling multiple current values ​​while the welding torch is stationary at the right-side swing limit position, discarding the maximum and minimum values, and taking the average value as the right-side limit welding current.

[0046] For example, the welding torch is controlled to swing according to a preset swing trajectory. When the torch reaches the left swing limit position, it is briefly held at that position. During this pause, the real-time welding current is sampled multiple times to obtain several sets of raw current sample values. The maximum and minimum values ​​in this batch of raw sample values ​​are removed to eliminate the influence of instantaneous pulse interference and sampling anomalies. The average value of the remaining valid current data is calculated, and this average value is the left limit welding current. Subsequently, the welding torch is controlled to continue swinging to the right swing limit position and remain stationary. The sampling, data filtering, and averaging methods are exactly the same as those used for the left limit position to obtain the right limit welding current.

[0047] This invention provides a method for detecting and tracking arc deviation in fillet welds based on decoupling coefficient compensation. The method samples the weld gun at its extreme position during the static phase and combines extreme value removal with average data processing to effectively filter out various on-site interferences and obtain accurate and stable left and right extreme welding currents, thereby improving the accuracy of subsequent calculations.

[0048] This embodiment provides a fillet weld arc deviation detection and tracking system based on decoupling coefficient compensation, such as... Figure 4 As shown, it includes: Welding power supply 201 is used to provide constant voltage output; The oscillating mechanism 202 is used to drive the welding torch to oscillate periodically perpendicular to the weld direction at a set amplitude. The current acquisition module 203 is used to synchronously acquire the welding current at the left swing limit and the right swing limit during the swing cycle; Controller 204 is configured to execute a fillet weld arc deviation detection and tracking method based on decoupling coefficient compensation in the above embodiments to obtain a lateral correction signal and / or a height correction signal. The actuator 205 includes a lateral drive unit and a height drive unit, which adjust the lateral position and / or welding height of the welding torch relative to the root of the fillet weld in real time according to the lateral correction signal and / or height correction signal output by the controller.

[0049] For example, such as Figure 5 As shown, the entire system comprises three parts: a welding machine, a robot body, and a controller. The welding machine consists of a welding power supply 201 and a current acquisition module 203. The robot body includes a robotic arm, a position encoder, and a welding torch. The robotic arm of the robot body functions as both a swing mechanism and an execution mechanism: on the one hand, it drives the welding torch to swing periodically according to set parameters to achieve process shaping; on the other hand, it adjusts the overall path according to the correction signal from the controller to achieve weld seam tracking, thus functioning as both a swing mechanism 202 and an execution mechanism 205. The controller 204 includes a motion control module and a current data processing module, which executes a fillet weld arc deviation detection and tracking method based on decoupling coefficient compensation in the above embodiment to obtain a lateral correction signal and / or a height correction signal.

[0050] The welding power source 201 provides a stable constant voltage output for the welding process, ensuring a constant welding arc voltage and avoiding interference from voltage fluctuations on the welding current. The oscillation mechanism 202 is assembled and connected to the welding torch, driving the torch to oscillate periodically along a direction perpendicular to the weld seam according to a preset oscillation amplitude and preset oscillation period. This allows the welding torch to regularly reach the left and right oscillation limit positions and pause briefly at both limit positions, providing stable mechanical operating conditions for collecting steady-state current at the limit positions.

[0051] The current acquisition module 203 is electrically connected to the signal terminal of the welding power supply 201, and can synchronously acquire the real-time welding current during the complete oscillation cycle of the welding torch. In particular, it performs multi-point continuous current sampling during the steady-state period when the welding torch is at the left and right oscillation limit positions, and obtains the left and right limit welding currents by averaging the sampled maximum and minimum values ​​respectively.

[0052] The controller 204 is communicatively connected to the current acquisition module 203, the swing mechanism 202, and the actuator 205. The controller has built-in and executes the aforementioned method for detecting and tracking arc deviation in fillet welds based on decoupling coefficient compensation. For details, please refer to the corresponding content of the method, which will not be elaborated here.

[0053] The actuator 205 is fixedly connected to the welding torch and includes a lateral drive unit and a height drive unit. The lateral drive unit and the height drive unit respectively receive the lateral correction signal and the height correction signal output by the controller, and adjust the lateral centering position and welding height of the welding torch relative to the root of the fillet weld in real time according to the positive sign and amplitude of the correction signal. This realizes real-time closed-loop correction and dynamic tracking of the lateral deviation and height deviation of the fillet weld, ensuring that the welding torch is always in the optimal welding position during the welding process.

[0054] Based on the above system, the weld seam tracking deviation detection method cyclically executes the following process during the control cycle of the welding system controller: Step 1: The controller issues a swing command, and the welding torch is driven by the swing mechanism to swing to the left; Step 2: After the welding torch reaches its left limit position, delay for 15ms to allow the current to stabilize. The current acquisition module continuously samples 20 current values ​​at a sampling rate of 1kHz, discards the maximum and minimum values, and then takes the average to obtain the result. ; Step 3: Swing the welding torch to the right, and collect and process the samples in the same manner. ; Step 4: The controller calculates the corrected transverse reference current according to the formula. and depth reference current; Step 5: Depth and Depth are respectively fed into the lateral PID controller and the height PID controller; Step 6: The two PID controllers output the horizontal servo motor drive signal and the height servo motor drive signal respectively, driving the actuator to adjust the welding torch position in real time; Step 7: Enter the next oscillation cycle and repeat steps 1-6.

[0055] This embodiment provides a fillet weld arc deviation detection and tracking system based on decoupling coefficient compensation, which can achieve precise decoupling of welding depth and transverse current coupling interference, and complete real-time detection and automatic tracking correction of transverse and height deviations of fillet welds.

[0056] This application also provides an electronic device, such as... Figure 6 As shown, processor 501 and memory 502 are connected via a bus or other means.

[0057] Processor 501 can be a central processing unit (CPU). Processor 501 can also be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or combinations of the above types of chips.

[0058] The memory 502, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer-executable programs, and modules, such as the program instructions / modules corresponding to a fillet weld arc deviation detection and tracking method based on decoupling coefficient compensation in this embodiment of the invention. The processor executes various functional applications and data processing by running the non-transitory software programs, instructions, and modules stored in the memory.

[0059] Memory 502 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created by the processor, etc. Furthermore, the memory may include high-speed random access memory and non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, memory 502 may optionally include memory remotely located relative to the processor, which can be connected to the processor via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0060] The one or more modules are stored in the memory 502, and when executed by the processor 501, they perform actions such as... Figure 1 The embodiment shown is a method for detecting and tracking arc deviation in fillet welds based on decoupling coefficient compensation.

[0061] For specific details regarding the aforementioned electronic devices, please refer to the relevant documentation. Figure 1 The relevant descriptions and effects in the illustrated embodiments are for understanding purposes only and will not be repeated here.

[0062] This embodiment also provides a computer storage medium storing computer-executable instructions that can execute one of the above-described methods for detecting and tracking arc deviation in fillet welds based on decoupling coefficient compensation. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk drive (HDD), or solid-state drive (SSD), etc.; the storage medium may also include combinations of the above types of memory.

[0063] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made to it in form and detail without departing from the scope defined by the claims of the present invention.

Claims

1. A method for detecting and tracking arc deviation in fillet welds based on decoupling coefficient compensation, characterized in that, include: Obtain welding process parameters, the left limit welding current, the right limit welding current, the transverse zero point current, and the expected average current at the standard welding height. Based on welding process parameters, the decoupling coefficient is determined. The decoupling coefficient characterizes the proportion of the difference signal change caused by the asymmetry of the base material to the depth change. Based on the decoupling coefficient, the left limit welding current, the right limit welding current, the transverse zero point current, and the expected average current at the standard welding height, the transverse reference current after decoupling compensation is determined. Based on the decoupled and compensated lateral reference current, the lateral correction signal is determined, and the lateral correction signal is used for weld lateral tracking control.

2. The method for detecting and tracking arc deviation in fillet welds based on decoupling coefficient compensation according to claim 1, characterized in that, Based on the decoupling coefficient, the left-side and right-side limiting welding currents of the welding torch, the lateral zero-point current, and the expected average current at the standard welding height, the lateral reference current after decoupling compensation is determined, including: Based on the decoupling coefficient, the left and right limit welding currents of the welding torch, and the expected average current at the standard welding height, the cross-interference compensation value is determined. Based on the left-side limit welding current, right-side limit welding current, transverse zero-point current, and cross-interference compensation value of the welding torch, the transverse reference current after decoupling compensation is determined.

3. The method for detecting and tracking arc deviation in fillet welds based on decoupling coefficient compensation according to claim 1, characterized in that, Based on welding process parameters, the decoupling coefficient is determined, including: Based on the welding process parameters, the corresponding decoupling coefficients are obtained by querying the pre-stored mapping table of welding process parameters and decoupling coefficients.

4. The method for detecting and tracking arc deviation in fillet welds based on decoupling coefficient compensation according to claim 3, characterized in that, The pre-stored mapping table of welding process parameters and decoupling coefficients is determined through the following process: S1, under specified welding process parameters, record the first left and right current difference and the average welding current of the first target side when the welding torch is welding at the standard depth position, the second left and right current difference and the average welding current of the second target side when the welding torch is welding at the target depth position, the first target side and the second target side are the same side, including the left side of the limit welding or the right side of the limit welding. S2, based on the first left and right current difference and the second left and right current difference, determine the change in the left and right current difference; S3, based on the average welding current of the first target side and the average welding current of the second target side, determine the amount of average current change caused by the depth change; S4. Based on the change in the difference between the left and right currents and the change in the average current, determine the preliminary decoupling coefficient for the corresponding depth change. S5, determine whether the stopping condition is met; if not, execute S6; if met, execute S7. S6, adjust the target depth position relative to the standard depth position upwards / downwards, and repeat steps S1-S5; S7, obtain the preliminary decoupling coefficients corresponding to the depth positions of multiple targets; S8 calculates the average of multiple preliminary decoupling coefficients, which is used as the decoupling coefficient corresponding to the specified welding process parameters.

5. The method for detecting and tracking arc deviation in fillet welds based on decoupling coefficient compensation according to claim 1, characterized in that, Also includes: Obtain the depth zero-point current; Determine the depth reference current based on the left and right limit welding currents of the welding torch, the depth zero point current, and the expected average current at the standard welding height. Based on the depth reference current, the height correction signal is determined, and the height correction signal is used for weld height tracking control.

6. The method for detecting and tracking arc deviation in fillet welds based on decoupling coefficient compensation according to claim 2, characterized in that, Based on the decoupling coefficient, the left-side and right-side limiting welding currents of the welding torch, and the expected average current at the standard welding height, the cross-interference compensation value is determined, including: Based on the left and right limit welding currents of the welding torch, the average value is calculated as the actual average current on both sides. The difference between the actual average current on the left and right sides and the expected average current at the standard welding height is used to determine the change in average current. The compensation direction is determined based on the left and right limit welding currents of the welding torch and a predetermined sign function. The cross-interference compensation value is determined based on the decoupling coefficient, the average current change, and the compensation direction.

7. A method for detecting and tracking arc deviation in fillet welds based on decoupling coefficient compensation according to claim 2 or 6, characterized in that, Based on the left-side and right-side limiting welding currents of the welding torch, the lateral zero-point current, and the cross-interference compensation value, the decoupled compensation lateral reference current is determined, including: The original lateral deviation signal is obtained by subtracting the left and right limit welding currents of the welding torch. The original lateral deviation signal is subtracted from the lateral zero-point current and the cross-interference compensation value to obtain the decoupled compensation lateral reference current.

8. A method for detecting and tracking arc deviation in fillet welds based on decoupling coefficient compensation according to any one of claims 1-6, characterized in that, Obtain the left-side and right-side limiting welding currents of the welding torch, including: During the period when the welding torch is at the left swing limit position, multiple current values ​​are continuously sampled. The maximum and minimum values ​​are removed and the average value is taken as the left limit welding current. During the period when the welding torch is at the right swing limit position, multiple current values ​​are continuously sampled. The maximum and minimum values ​​are removed, and the average value is taken as the right limit welding current.

9. A fillet weld arc deviation detection and tracking system based on decoupling coefficient compensation, characterized in that, include: Welding power supply, used to provide constant voltage output; The oscillating mechanism is used to drive the welding torch to oscillate periodically perpendicular to the weld direction at a set amplitude. The current acquisition module is used to simultaneously acquire the welding current at the left and right swing limits during the swing cycle. The controller is configured to execute the fillet weld arc deviation detection and tracking method based on decoupling coefficient compensation as described in any one of claims 1-8, and obtain a lateral correction signal and / or a height correction signal; The actuator, including a lateral drive unit and a height drive unit, adjusts the lateral position and / or welding height of the welding torch relative to the root of the fillet weld in real time according to the lateral correction signal and / or height correction signal output by the controller.

10. A computer storage medium storing computer instructions thereon, characterized in that, When executed by the processor, this instruction implements the steps of the fillet weld arc deviation detection and tracking method based on decoupling coefficient compensation as described in any one of claims 1-8.

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