CN113210805A - MIG welding deviation rectifying method based on industrial thermal imager and visible light camera double vision - Google Patents
MIG welding deviation rectifying method based on industrial thermal imager and visible light camera double vision Download PDFInfo
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- CN113210805A CN113210805A CN202110510198.8A CN202110510198A CN113210805A CN 113210805 A CN113210805 A CN 113210805A CN 202110510198 A CN202110510198 A CN 202110510198A CN 113210805 A CN113210805 A CN 113210805A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/12—Automatic feeding or moving of electrodes or work for spot or seam welding or cutting
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/16—Arc welding or cutting making use of shielding gas
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/24—Features related to electrodes
- B23K9/28—Supporting devices for electrodes
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/32—Accessories
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Abstract
The invention discloses a MIG welding deviation rectifying method based on double vision of an industrial thermal imager and a visible light camera, which comprises the following steps of S1: and transmitting a first image generated by the industrial thermal imager and a second image generated by the visible light camera to a DSP image processing unit of the industrial control box for preprocessing so as to obtain a first preprocessed image and a second preprocessed image. The invention discloses a MIG welding deviation rectifying method based on double vision of an industrial thermal imager and a visible light camera, which uses the industrial thermal imager to shoot a molten pool and can effectively filter the interference of welding arc light, smoke, splashing and the like on the image of the molten pool; the visible light cameras are used for only shooting the welding seams with no dominant infrared imaging to obtain clear and stable welding seam images, each camera only shoots the parts where the camera is good at, and the situation that a molten pool and the welding seams cannot be shot clearly at the same time is avoided.
Description
Technical Field
The invention belongs to the technical field of MIG welding deviation correction (melt inert-gas welding), and particularly relates to a MIG welding deviation correction method based on double vision of an industrial thermal imager and a visible light camera.
Background
An industrial visible light camera and an optical filter are introduced into the MIG welding to form an optical system to obtain a stable and clear welding pool image, and automatic error correction is carried out on a welding gun and a welding line through analysis of the welding pool image. The main principle is as follows:
in the process of pipeline backing welding, the practical environment is not ideal, and various factors such as interference, deformation, workpiece defects and the like exist, so that a molten pool formed by a welding gun in the welding process is not completely aligned with a welding seam. In order to accurately detect the positions of a molten pool and a welding seam in real time in the welding process and enable various parameters to adapt to the changes of a welding object and the environment, a welding deviation rectifying system is required. A visible light camera is adopted to shoot a molten pool and a welding seam in the welding process, the obtained image is transmitted to an industrial control box, an industrial personal computer in the control box performs analysis and operation to obtain the current deviation correction amount in the welding process, and then a welding gun is subjected to deviation correction through a motion control card to realize acquisition of deviation correction control closed-loop feedback.
There are three major disadvantages to this approach:
1. the change of arc intensity is very big during welding, even increase the filter and also difficult to the interference such as arc, smog and splash that constantly changes clean.
2. The visible light camera needs to photograph both the weld pool and the weld seam, but the brightness difference between the two is large in the actual welding process, and only one of the two can be photographed clearly.
3. The industrial control box as the control platform comprises units such as an industrial personal computer, a motion control card, an image acquisition card and the like, and has high price and larger volume.
Therefore, the above problems are further improved.
Disclosure of Invention
The invention mainly aims to provide a MIG welding deviation rectifying method based on double vision of an industrial thermal imager and a visible light camera, wherein the industrial thermal imager is used for shooting a molten pool, so that the interference of welding arc light, smoke, splashing and the like on the molten pool image can be effectively filtered; the method has the advantages that the visible light cameras are used for only shooting the welding seams with the infrared imaging not dominant, clear and stable welding seam images are obtained, each camera only shoots the part where the camera is good at, the situation that a molten pool and the welding seams cannot be shot clearly at the same time is avoided, and in addition, the embedded DSP image processing unit is adopted, so that the size is smaller and the cost is lower compared with an industrial control box.
In order to achieve the above purpose, the invention provides a MIG welding deviation rectifying method based on double vision of an industrial thermal imager and a visible light camera, which is used for automatically correcting errors of a MIG welding gun and a welding line, and comprises the following steps:
step S1: transmitting a first image generated by an industrial thermal imager and a second image generated by a visible light camera to a DSP image processing unit of an industrial control box for preprocessing to obtain a first preprocessed image and a second preprocessed image, and performing image fusion on the first preprocessed image and the second preprocessed image to obtain image fusion data;
step S2: respectively carrying out boundary algorithm on a first preprocessing image and a second preprocessing image in the image fusion data to obtain a molten pool center coordinate and a welding seam center coordinate, and transmitting a welding offset obtained by calculating the molten pool center coordinate and the welding seam center coordinate to a motion control unit of the industrial control box;
step S3: the motion control unit generates a control signal according to the welding offset and transmits the control signal to a motor driver of a transverse swing motion structure of the welding gun so as to control the welding gun to automatically correct the deviation.
As a further preferable technical solution of the above technical solution, step S0 is further included before step S1, and step S0 is specifically implemented as the following steps:
step S0.1: the industrial thermal imager and the visible light camera are both mounted on the bracket and are simultaneously aligned with the welding area;
step S0.2: a near-infrared filter is additionally arranged in front of a lens of the visible light camera to enable light transmitting a near-infrared band to be perceived by the visible light camera, and the zoom multiple and the shooting angle are adjusted (consistency of shooting pictures is guaranteed), so that the visible light camera shoots a first image comprising a welding seam image;
step S0.3: an infrared filter is additionally arranged in front of a lens of the industrial thermal imager to filter visible light wave bands with high intensity in a welding light arc, the sensing range of the industrial thermal imager is adjusted to a molten pool temperature range (a single and stable molten pool image can be generated in the industrial thermal imager and is slightly interfered by arc light, smoke, splashing and the like), and the zooming times and the shooting angles are adjusted (the consistency of a shot image is ensured), so that the industrial thermal imager shoots a second image comprising the molten pool image.
As a further preferable embodiment of the above technical means, step S1 is specifically implemented as the following steps:
step S1.1: the first image is subjected to preprocessing comprising filtering processing, sharpening enhancement and gray scale transformation to form a first preprocessed image;
step S1.2: the second image is subjected to preprocessing comprising filtering processing, sharpening enhancement and gray scale transformation to form a second preprocessed image;
step S1.3: and carrying out image fusion on the first preprocessed image and the second preprocessed image through an image registration algorithm to obtain image fusion data.
As a more preferable embodiment of the above-mentioned technical means, the step S3 is followed by further comprising:
step S4: and in the welding process, feeding back the welding offset obtained in real time to control the automatic deviation rectification of the welding gun until the deviation of the central coordinate of the molten pool and the central coordinate of the welding seam is within a preset deviation threshold range.
As a further preferable technical scheme of the above technical scheme, in step S0.1, the industrial thermal imager and the visible light camera are both mounted on the bracket through the slide rail, so that the industrial thermal imager and the visible light camera are matched with welding areas of different sizes, and are automatically tracked and locked through the slide rail (the sizes of the welded pipes are different, and the consistency of the shot pictures cannot be guaranteed by adjusting the zoom times and shooting angles of the cameras sometimes, so that the industrial thermal imager and the visible light camera are controlled to move to the optimal shooting position by feeding back the welding areas through the industrial control box).
Drawings
FIG. 1 is a schematic structural diagram of a MIG welding deviation rectifying method based on double vision of an industrial thermal imager and a visible light camera.
FIG. 2 is a flow chart of the MIG welding deviation rectifying method based on double vision of the industrial thermal imager and the visible light camera.
The reference numerals include: 1. an industrial control cabinet; 2. an industrial thermal imager; 3. a visible light camera; 4. a welding gun; 5. a molten pool; 6. welding seams; 7. a pipeline.
Detailed Description
The following description is presented to disclose the invention so as to enable any person skilled in the art to practice the invention. The preferred embodiments in the following description are given by way of example only, and other obvious variations will occur to those skilled in the art. The basic principles of the invention, as defined in the following description, may be applied to other embodiments, variations, modifications, equivalents, and other technical solutions without departing from the spirit and scope of the invention.
In the preferred embodiment of the present invention, those skilled in the art should note that the welding gun, motor driver, etc. to which the present invention relates may be regarded as prior art.
PREFERRED EMBODIMENTS
The invention discloses an MIG welding deviation rectifying method based on double vision of an industrial thermal imager and a visible light camera, which is used for automatically correcting errors of an MIG welding gun and a welding line and comprises the following steps:
step S1: transmitting a first image generated by an industrial thermal imager and a second image generated by a visible light camera to a DSP image processing unit of an industrial control box for preprocessing to obtain a first preprocessed image and a second preprocessed image, and performing image fusion on the first preprocessed image and the second preprocessed image to obtain image fusion data (the industrial thermal imager can remove interference of arc light, smoke, splash and the like due to the imaging principle of the industrial thermal imager, and can obtain a clearer and more stable molten pool image, and the visible light image mainly performs parameter optimization on a welding seam with unobvious thermal gradient to obtain a clear welding seam image);
step S2: respectively carrying out boundary algorithm on a first preprocessing image and a second preprocessing image in the image fusion data to obtain a molten pool center coordinate and a welding seam center coordinate, and transmitting a welding offset obtained by calculating the molten pool center coordinate and the welding seam center coordinate to a motion control unit of the industrial control box;
step S3: the motion control unit generates a control signal according to the welding offset and transmits the control signal to a motor driver of a transverse swing motion structure of the welding gun so as to control the welding gun to automatically correct the deviation.
Specifically, step S0 is further included before step S1, and step S0 is specifically implemented as the following steps:
step S0.1: the industrial thermal imager and the visible light camera are both mounted on the bracket and are simultaneously aligned with the welding area;
step S0.2: a near-infrared filter is additionally arranged in front of a lens of the visible light camera to enable light transmitting a near-infrared band to be perceived by the visible light camera, and the zoom multiple and the shooting angle are adjusted (consistency of shooting pictures is guaranteed), so that the visible light camera shoots a first image comprising a welding seam image;
step S0.3: an infrared filter is additionally arranged in front of a lens of the industrial thermal imager to filter visible light wave bands with high intensity in a welding light arc, the sensing range of the industrial thermal imager is adjusted to a molten pool temperature range (a single and stable molten pool image can be generated in the industrial thermal imager and is slightly interfered by arc light, smoke, splashing and the like), and the zooming times and the shooting angles are adjusted (the consistency of a shot image is ensured), so that the industrial thermal imager shoots a second image comprising the molten pool image.
More specifically, step S1 is specifically implemented as the following steps:
step S1.1: the first image is subjected to preprocessing comprising filtering processing, sharpening enhancement and gray scale transformation to form a first preprocessed image;
step S1.2: the second image is subjected to preprocessing comprising filtering processing, sharpening enhancement and gray scale transformation to form a second preprocessed image;
step S1.3: and carrying out image fusion on the first preprocessed image and the second preprocessed image through an image registration algorithm to obtain image fusion data.
Visible light + infrared light image fusion principle:
the visible light camera has high imaging quality and stable imaging, and is widely applied to the industrial field related to vision processing. In the embodiment, the visible light camera shoots the weld, and the visible light camera is not aligned with the molten pool area, so that only a single weld image can be seen during imaging. The industrial thermal imager performs imaging through infrared rays generated by thermal radiation of a measured target, the thermal radiation generated by a molten pool is large and stable in the welding process, the sensing range of the industrial thermal imager is adjusted to be about the temperature of the molten pool, a single and stable molten pool image can be generated in the industrial thermal imager, and arc light and other interference sources are removed.
Further, step S3 is followed by:
step S4: and in the welding process, feeding back the welding offset obtained in real time to control the automatic deviation rectification of the welding gun until the deviation of the central coordinate of the molten pool and the central coordinate of the welding seam is within a preset deviation threshold range.
Furthermore, in the step S0.1, the industrial thermal imager and the visible light camera are both mounted on the bracket through the slide rail, so that the industrial thermal imager and the visible light camera are matched with welding areas of different sizes, and are automatically tracked and locked through the slide rail (the sizes of the welding pipes are different, and the consistency of the shot images cannot be guaranteed by adjusting the zoom times and shooting angles of the cameras sometimes, so that the industrial thermal imager and the visible light camera are controlled to move to the optimal shooting position by feeding back the welding areas through the industrial control box).
It should be noted that the present invention may also use two visible light cameras to respectively photograph the weld pool and the weld seam, and configure the optical filter and the exposure parameters according to the characteristics of the weld pool and the weld seam. The images of the molten pool and the welding seam can be shot clearly at the same time, but the interference of arc light, smoke and splashing is larger, the requirement on an image processing algorithm is higher, and the deviation rectification precision is influenced.
It should be noted that the technical features of the welding gun, the motor driver, etc. related to the present patent application should be regarded as the prior art, and the specific structure, the operation principle, the control mode and the spatial arrangement mode of the technical features may be selected conventionally in the field, and should not be regarded as the invention point of the present patent, and the present patent is not further specifically described in detail.
It will be apparent to those skilled in the art that modifications and equivalents may be made in the embodiments and/or portions thereof without departing from the spirit and scope of the present invention.
Claims (5)
1. An MIG welding deviation rectifying method based on double vision of an industrial thermal imager and a visible light camera is used for automatically correcting errors of an MIG welding gun and a welding line, and is characterized by comprising the following steps of:
step S1: transmitting a first image generated by an industrial thermal imager and a second image generated by a visible light camera to a DSP image processing unit of an industrial control box for preprocessing to obtain a first preprocessed image and a second preprocessed image, and performing image fusion on the first preprocessed image and the second preprocessed image to obtain image fusion data;
step S2: respectively carrying out boundary algorithm on a first preprocessing image and a second preprocessing image in the image fusion data to obtain a molten pool center coordinate and a welding seam center coordinate, and transmitting a welding offset obtained by calculating the molten pool center coordinate and the welding seam center coordinate to a motion control unit of the industrial control box;
step S3: the motion control unit generates a control signal according to the welding offset and transmits the control signal to a motor driver of a transverse swing motion structure of the welding gun so as to control the welding gun to automatically correct the deviation.
2. The MIG welding deviation rectification method based on the double vision of the industrial thermal imager and the visible light camera as claimed in claim 1, wherein step S1 is preceded by step S0, and step S0 is implemented as the following steps:
step S0.1: the industrial thermal imager and the visible light camera are both mounted on the bracket and are simultaneously aligned with the welding area;
step S0.2: a near-infrared filter is additionally arranged in front of a lens of a visible light camera so as to enable light transmitting a near-infrared band to be perceived by the visible light camera, and the zooming multiple and the shooting angle are adjusted so that the visible light camera shoots a first image comprising a welding seam image;
step S0.3: an infrared filter is additionally arranged in front of a lens of the industrial thermal imager to filter visible light wave bands with high intensity in a welding light arc, the sensing range of the industrial thermal imager is adjusted to the temperature range of a molten pool, and the zoom times and the shooting angle are adjusted, so that the industrial thermal imager shoots a second image comprising the image of the molten pool.
3. The MIG welding deviation rectification method based on the double vision of the industrial thermal imager and the visible light camera as claimed in claim 2, wherein the step S1 is implemented as the following steps:
step S1.1: the first image is subjected to preprocessing comprising filtering processing, sharpening enhancement and gray scale transformation to form a first preprocessed image;
step S1.2: the second image is subjected to preprocessing comprising filtering processing, sharpening enhancement and gray scale transformation to form a second preprocessed image;
step S1.3: and carrying out image fusion on the first preprocessed image and the second preprocessed image through an image registration algorithm to obtain image fusion data.
4. The MIG welding deviation rectification method based on the double vision of the industrial thermal imager and the visible light camera as claimed in claim 3, further comprising after the step S3:
step S4: and in the welding process, feeding back the welding offset obtained in real time to control the automatic deviation rectification of the welding gun until the deviation of the central coordinate of the molten pool and the central coordinate of the welding seam is within a preset deviation threshold range.
5. The MIG welding deviation rectifying method based on the double vision of the industrial thermal imager and the visible light camera as recited in claim 4, wherein in the step S0.1, the industrial thermal imager and the visible light camera are both mounted on the bracket through slide rails, so that the industrial thermal imager and the visible light camera are matched with welding areas with different sizes, and automatic tracking and locking are performed through the slide rails.
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Application publication date: 20210806 |