An intelligent welding tracking method

Abstract

The application relates to the field of automatic welding technology and discloses an intelligent welding tracking method, which comprises the following steps: acquiring original structure size data model of a welding structure; using a welding seam tracking sensor which is separated from a welding gun to measure the positions of preset measuring points on the welding structure to obtain measuring position data; and calculating the track of an actual welding seam on the welding structure according to the measuring position data and the original structure size data model; the preset measuring points are determined according to the shape of the welding seam, and for straight-line welding seams, the preset measuring points are two points on the welding seam. The welding seam tracking sensor is separated from the welding gun, so that the sensor is completely separated from the splashing, strong arc light and high-temperature radiation environment of the welding area during the measuring process, the interference of the welding process on the measuring signal is fundamentally eliminated, and the stability and reliability of the welding seam tracking system in long-term continuous operation are remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of automated welding technology, and in particular to an intelligent welding tracking method. Background Technology

[0002] The most fundamental difference between automated and intelligent welding lies in the presence or absence of sensing capabilities during the welding process. Automated welding is essentially devoid of sensing capabilities; even with high-precision welding robots, it can only repeatedly operate according to pre-set welding parameters and trajectories, unable to adapt to various changes in actual working conditions. Intelligent welding, on the other hand, can monitor changes during the welding process in real time, possessing sensing capabilities. Among various sensing functions, the sensing of weld seam position is particularly important because the welded workpiece itself has assembly errors, and the actual weld seam position often deviates from the design theoretical value. Simultaneously, the thermal deformation generated during welding causes the weld seam position to change in real time during the welding process. Therefore, weld seam tracking technology has become one of the key technologies for realizing intelligent welding.

[0003] Currently, most research on weld seam tracking focuses on the weld seam tracking sensor itself mounted on the welding torch. The research emphasizes improving individual performance indicators such as detection accuracy, response speed, and anti-interference capability, while less attention is paid to the systematic research of weld seam tracking methods. Undeniably, improving the performance of weld seam tracking sensors is crucial for achieving weld seam tracking, and existing sensors can generally achieve real-time and accurate detection of weld seam position changes. However, in practical industrial applications, directly mounting the sensor on the welding torch still presents many insurmountable problems. For example, in the compact space of a welding structure, the sensor integrated with the welding torch is bulky, resulting in insufficient accessibility and difficulty in operating in narrow areas; the visual effect of the sensor is significantly reduced by the spatter and strong arc light generated during welding, affecting measurement accuracy; when tracking weld seams with large curvature, the lead distance between the sensor and the welding torch easily leads to tracking lag or deviation. Therefore, existing general-purpose weld seam tracking sensors are subject to many limitations in practical use and struggle to operate stably for extended periods in harsh welding environments.

[0004] As more and more engineering applications are discovered, current tracking systems based on general-purpose weld seam tracking sensors are not ideal for mass-produced welded structural components. On the one hand, the integration of the sensor with the welding torch means it is constantly exposed to harsh environments of high temperature, spatter, and arc radiation, resulting in rapid equipment wear and high maintenance costs. On the other hand, due to the lack of utilization of the original dimensional data model of the welded workpiece, existing methods usually require continuous scanning or dense sampling of the entire weld seam to determine the weld seam trajectory, resulting in large data acquisition volumes and low processing efficiency. Summary of the Invention

[0005] This invention provides an intelligent welding tracking method to solve the existing technical problems, thereby resolving the issues present in the background art.

[0006] To solve the above-mentioned technical problems, according to one aspect of the present invention, more specifically, an intelligent welding tracking method, comprising the following steps:

[0007] Step 1: Obtain the original structural dimension data model of the welded structural components;

[0008] Step 2: Using a weld seam tracking sensor that is separately installed from the welding torch, the position of a preset measurement point on the welded structure is measured to obtain measurement position data;

[0009] Step 3: Calculate the trajectory of the actual weld on the welded structural component based on the measured position data and the original structural dimension data model.

[0010] Furthermore, the preset measurement points are determined according to the shape of the weld: for a straight weld, the preset measurement points are two points on the weld; for a circular arc weld, the preset measurement points are three points on the weld.

[0011] Furthermore, the position measurement of the preset measurement points on the welded structural component is an offline measurement.

[0012] Furthermore, the position measurement of the preset measurement points on the welded structural components is performed online in real time.

[0013] Furthermore, the online real-time measurement includes: when the welding deformation law is known, calculating the position change of any point on the weld by measuring the position change of the preset measurement points in real time.

[0014] Furthermore, the weld seam tracking sensor is mounted on the measuring robot arm, and the welding torch is mounted on the welding robot arm. The measuring robot arm and the welding robot arm work together and exchange position information data in real time.

[0015] Furthermore, the measuring robot arm is used to perform pre-welding positioning and real-time tracking functions;

[0016] For a welded workpiece with multiple weld seams, the measuring robot performs pre-welding positioning of other weld seams while the welding robot is welding the current weld seam, and detects welding deformation at key points to correct the weld seam trajectory in real time.

[0017] Furthermore, the original structural dimension data model of the welded structural component is a known three-dimensional dimension data model of the welded structural component.

[0018] Furthermore, the trajectory of the actual weld is composed of a combination of straight line segments or circular arc segments.

[0019] The intelligent welding tracking method provided by this invention has the following advantages compared to existing technologies:

[0020] 1. By separating the weld seam tracking sensor from the welding torch, the sensor is completely isolated from the spatter, strong arc light and high temperature radiation environment of the welding area during the measurement process, which fundamentally eliminates the interference of the welding process on the measurement signal and significantly improves the stability and reliability of the weld seam tracking system in long-term continuous operation.

[0021] 2. This invention can reconstruct the actual weld trajectory by measuring the position of only a limited number of preset measurement points based on the original size data model of the known welded structural component. This greatly reduces the amount of data acquisition and calculation in the weld tracking process, improves the system response speed, and reduces hardware costs and implementation complexity.

[0022] 3. This invention can determine the actual position of the weld by measuring two preset points for straight welds and three preset points for circular welds, making the calculation model of the weld trajectory simple and efficient. It eliminates the need for continuous scanning or dense sampling of the entire weld, simplifying the data processing flow and reducing the computational burden on the system.

[0023] 4. This invention supports both offline and online real-time measurement methods, allowing for flexible selection of measurement modes based on the deformation characteristics and production cycle requirements of different welded workpieces. Offline measurement can shorten production auxiliary time for welded structures with high rigidity and small deformation, while online real-time measurement can ensure tracking accuracy for welded structures with large deformation, thus expanding the applicability of the method.

[0024] 5. This invention can calculate the deformation of any point on the weld by measuring the position changes of only a few key points in real time under the condition that the welding deformation law is known. This avoids the need to continuously track and measure the entire weld during the welding process, making the data processing of real-time weld tracking more efficient and faster, while ensuring tracking accuracy. Attached Figure Description

[0025] Figure 1 This is a schematic diagram illustrating the working principle of weld seam tracking in small-diameter inner circumferential welds according to the present invention.

[0026] Figure 2 This is a schematic diagram illustrating the working principle of weld seam tracking for the angle steel splicing rectangular straight weld seam of the present invention. Detailed Implementation

[0027] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention.

[0028] Specific Implementation Method 1: Weld Tracking for Small-Diameter Inner Circumferential Seam Welding

[0029] The following is combined with Figure 1 The first specific embodiment of the present invention is described below.

[0030] like Figure 1 As shown, the working principle of the weld seam tracking of the small-diameter inner ring weld of the present invention is as follows: the welding torch 2 is placed inside the inner ring 1 of the diameter for welding operations, while the weld seam tracking sensor 3 is installed outside the inner ring 1 of the small diameter, thereby realizing the separate setting of the weld seam tracking sensor 3 and the welding torch 2.

[0031] Before welding, the original structural dimension data model of the welded structural component (i.e., the small-diameter inner ring component 1) is first obtained. This original structural dimension data model is a known three-dimensional dimension data model of the welded structural component.

[0032] After welding begins, the weld seam tracking sensor 3, installed on the outer ring, measures the positions of preset measurement points on the welded structure to obtain position data. For the inner ring seam, a circular arc weld, the preset measurement points are three points on the weld; measuring these three points determines the actual position of the weld. Based on the measured position data of the three points and the known original structural dimension data model, the trajectory of the actual circular arc weld can be calculated.

[0033] Because the weld seam tracking sensor 3 is set separately from the welding torch 2, the weld seam tracking sensor 3 is not affected by spatter and strong arc light during the welding process, nor is it limited by the narrow welding space of the small-diameter inner ring, and can stably and reliably acquire measurement data.

[0034] Specific Implementation Method Two: Weld Tracking of Straight Welds in Angle Steel Slab Assembly

[0035] The following is combined with Figure 2 The second specific embodiment of the present invention will be described.

[0036] The working principle of the weld seam tracking of the angle steel splicing rectangular straight weld seam of the present invention is as follows: Figure 2 As shown. Among them, 100 is the angle steel slab workpiece that has been assembled and tack-fixed. The two ends of the angle steel slab workpiece 100 are fixed on the clamps of positioners 401 and 402, and positioners 401 and 402 can rotate 360° synchronously.

[0037] Before welding, the original structural dimension data model of the angle steel square workpiece is first obtained.

[0038] like Figure 2 As shown, the clamping position reference point L is 0°, and the measurement point corresponding to the position sensor 300 is H, which is 90° away from L. The position sensor 300 is set separately from the welding torch.

[0039] During welding, a position sensor 300 is used to measure the position of a preset measurement point H on the welded structural component, obtaining measurement position data. Specifically, the height signal of the position sensor 300, i.e., the height distance Z' of the position sensor relative to point H, corresponds to the horizontal deviation X of the angle steel slab; the horizontal signal of the position sensor 300, i.e., the horizontal distance X' of the position sensor relative to point H, corresponds to the vertical deviation Z of the angle steel slab. The position of the position sensor along the length Y of the angle steel slab is known. This allows for the separate setting of the position sensor 300 from the welding torch 201 and welding torch 202.

[0040] For a straight weld seam where angle steel is spliced ​​into a square, two points on the weld are preset as measurement points. Measuring these two points determines the actual position of the weld. Based on the measured position data of the two points and the known original structural dimension data model, and according to the mathematical model of the deformation law of the angle steel splicing, the deformation at any point along the Y direction can be calculated, thus obtaining the trajectory of the actual straight weld seam.

[0041] In this specific embodiment, the position measurement of preset measurement points on the welded structural component is performed online in real time. Specifically, given that the welding deformation law is known, the position change of any point on the weld can be calculated by measuring the position change of the preset measurement points in real time, thus achieving real-time weld tracking.

[0042] Specific Implementation Method 3: Intelligent Welding System with Dual Robotic Arms

[0043] A more general implementation of an intelligent welding system with weld seam tracking function is as follows.

[0044] The system consists of two (or more) robotic arms. One robotic arm is a welding robotic arm carrying a welding torch; the other robotic arm is a measuring robotic arm carrying a position sensor (i.e., a weld seam tracking sensor). The weld seam tracking sensor and the welding torch are separately mounted on different robotic arms.

[0045] Based on offline programming, the two robotic arms work collaboratively and exchange position information data in real time. The measuring robotic arm is responsible for both pre-welding positioning and real-time tracking.

[0046] The specific working process is as follows: First, the original structural dimension data model of the welded structural component is obtained. The measuring robot arm uses its onboard position sensors to measure the positions of preset measurement points on the welded structural component, obtaining the measurement position data. Based on the measurement position data and the original structural dimension data model, the trajectory of the actual weld seam on the welded structural component is calculated.

[0047] For complex welded workpieces consisting of multiple weld seams, the measuring robot can work in parallel with the welding robot after completing the positioning of the first weld seam: while the welding robot is welding the current weld seam, the measuring robot completes the positioning of other weld seams, and at the same time detects the welding deformation of key points and corrects the weld seam trajectory in real time.

[0048] In this specific embodiment, the position measurement of preset measurement points on the welded structural component can be performed online in real time. Given that the welding deformation pattern is known, the positional change of any point on the weld can be calculated by measuring the positional changes of the preset measurement points in real time.

[0049] The embodiments 1, 2, and 3 described above are merely preferred embodiments of the present invention, and other embodiments are also possible. The core idea of ​​the present invention is to separate the weld seam tracking sensor from the welding torch, and guide the welding torch to align with the weld seam by measuring the position signals of points related to the weld seam position on the workpiece. Those skilled in the art can make equivalent modifications or substitutions without departing from the spirit of the present invention, and these equivalent modifications or substitutions are all included within the scope set forth in the claims of this application.

[0050] For example, more complex welds can theoretically be viewed as a combination of straight lines and arcs. Accordingly, the number and location of preset measurement points can be adaptively selected according to the shape of the weld.

[0051] For example, for welded structures with high rigidity and small deformation, the position measurement of preset measurement points on the welded structure can be carried out offline. By measuring offline and combining it with the original data model, the actual weld trajectory can be reconstructed.

[0052] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. An intelligent welding tracking method, characterized in that, Includes the following steps: Step 1: Obtain the original structural dimension data model of the welded structural components; Step 2: Using a weld seam tracking sensor that is separately installed from the welding torch, the position of a preset measurement point on the welded structure is measured to obtain measurement position data; Step 3: Calculate the trajectory of the actual weld on the welded structural component based on the measured position data and the original structural dimension data model.

2. The intelligent welding tracking method according to claim 1, characterized in that: The preset measurement points are determined according to the shape of the weld: for a straight weld, the preset measurement points are two points on the weld; for a circular arc weld, the preset measurement points are three points on the weld.

3. The intelligent welding tracking method according to claim 1, characterized in that: The position measurement of the preset measurement points on the welded structural components is an offline measurement.

4. The intelligent welding tracking method according to claim 1, characterized in that: The position measurement of the preset measurement points on the welded structural components is performed online in real time.

5. The intelligent welding tracking method according to claim 4, characterized in that: The online real-time measurement includes: when the welding deformation law is known, calculating the position change of any point on the weld by measuring the position change of the preset measurement points in real time.

6. The intelligent welding tracking method according to claim 1, characterized in that: The weld seam tracking sensor is mounted on the measuring robot arm, and the welding torch is mounted on the welding robot arm. The measuring robot arm and the welding robot arm work together and exchange position information data in real time.

7. The intelligent welding tracking method according to claim 6, characterized in that: The measuring robot arm is used to perform pre-welding positioning and real-time tracking functions; For a welded workpiece with multiple weld seams, the measuring robot performs pre-welding positioning of other weld seams while the welding robot is welding the current weld seam, and detects welding deformation at key points to correct the weld seam trajectory in real time.

8. The intelligent welding tracking method according to claim 1, characterized in that: The original structural dimension data model of the welded structure is a known three-dimensional dimension data model of the welded structure.

9. The intelligent welding tracking method according to claim 1, characterized in that: The actual weld trajectory is composed of a combination of straight line segments or circular arc segments.

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