CN117548869A - Welding stress measurement method and system based on image processing - Google Patents
Welding stress measurement method and system based on image processing Download PDFInfo
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- CN117548869A CN117548869A CN202311791395.7A CN202311791395A CN117548869A CN 117548869 A CN117548869 A CN 117548869A CN 202311791395 A CN202311791395 A CN 202311791395A CN 117548869 A CN117548869 A CN 117548869A
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- 238000003466 welding Methods 0.000 title claims abstract description 156
- 238000012545 processing Methods 0.000 title claims abstract description 40
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- 238000005259 measurement Methods 0.000 claims abstract description 21
- 238000010147 laser engraving Methods 0.000 claims abstract description 14
- 238000009434 installation Methods 0.000 claims description 17
- 238000003384 imaging method Methods 0.000 claims description 4
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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
- B23K26/00—Working by laser beam, e.g. welding, cutting or boring
- B23K26/70—Auxiliary operations or equipment
- B23K26/702—Auxiliary equipment
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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
- B23K26/00—Working by laser beam, e.g. welding, cutting or boring
- B23K26/36—Removing material
- B23K26/362—Laser etching
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- Length Measuring Devices By Optical Means (AREA)
Abstract
The welding stress measurement system based on image processing comprises a laser engraving unit, a camera shooting unit, an engraving and camera shooting position driving unit and a graph analysis unit; the carving and shooting position driving unit drives the laser carving unit to mark the welding workpiece with more than two marks; after welding, the camera shooting unit shoots the mark to obtain a mark picture; and the graph analysis unit analyzes the welding stress change of the workpiece according to the relative position change of the welded mark. In the welding stress measuring method based on image processing, more than two marks are marked on a welding workpiece; photographing the mark after welding; and analyzing the welding stress change of the workpiece according to the relative position change of the marks before and after welding. By means of the mark, stress change information can be obtained through photographing, strain gauges or other sensing mechanisms are not required to be arranged for stress obtaining, and the system and the method are high-efficiency and convenient stress measurement systems and methods without direct contact, and can better meet construction requirements of bridge construction of a steel structure.
Description
Technical Field
The application belongs to the technical field of welding, and particularly relates to a welding stress measurement method and system based on image processing.
Background
Welding is a method of joining workpieces by heat or pressure, or a combination of both, with or without filler material. The essence is that the metal atoms of two separated surfaces are close to the lattice distance (0.3-0.5 nm) to form a metal bond through a proper physical-chemical process, so that the two metals are connected into a whole. Welding has many advantages over other processes: high production efficiency, low production cost, high joint strength, flexible and changeable processing form, simple structure, good compactness and the like. Therefore, welding is widely used in the mechanical manufacturing industry: the iron and steel industry, the energy industry,
the shipbuilding industry, the automotive industry, the aerospace industry, and the electronics industry.
The welding process is a nonlinear process of locally heating and cooling the metal material. Because of local heating, a great temperature gradient is generated in the welding line and the heat affected zone, heated metal is blocked by surrounding cooling metal, free expansion and contraction cannot be performed, and stress is generated inside. Because of uneven heating and cooling in the welding process, the internal stress of the base metal is uneven, and the internal stress of certain parts exceeds the yield limit of the material to generate plastic strain. The accumulation of plastic strain throughout the welding process results in the generation of residual stresses and weld deformations.
On the one hand, the welding deformation can reduce the bearing capacity of the welding piece and influence the safety performance of the structure where the welding piece is positioned. The additional bending moment and stress concentration caused by welding deformation and residual stress under working load are main causes of early failure of the welded structure and also one of causes of the reduction of the fatigue strength of the welded structure. On the other hand, welding distortion may reduce structural dimensional accuracy. In the first-stage assembly and closure process of the parts, welding deformation is continuously accumulated, the size of closure sections is greatly different from the original design size, and sometimes the assembly is difficult. Deformation correction is both time consuming and costly. The straightening deformation by heating causes embrittlement of the structural material, resulting in low stress failure. Thus, accurately predicting and controlling structural deformations of the weld during welding is of great importance for improving the weld quality.
In the prior art, steel structure welding bridges are increasingly widely used, welding stress is inevitably generated in the process of building and repairing the steel structure bridges due to uneven local heating of welding, and the damage of the welding stress is self-evident. The welding stress can cause potential safety hazards in the bridge, so that the magnitude of the actually measured welding stress is very important. In the prior art, welding stress measurement, especially stress measurement during and after bridge metal welding, is an important link for bridge safety assurance.
The traditional stress measurement method has the defects of expensive equipment, complex operation, inadaptation to the condition of the construction site and incapability of meeting the requirement of the construction site. One of the traditional methods is to test by a method of sticking strain gauges, and the testing equipment is expensive and difficult to operate on site.
Welding stress is inevitably generated in the process of building and repairing the steel structure bridge, and the damage of the welding stress is self-evident. The traditional method is to test by a method of attaching a strain gauge, and has the problems of expensive test equipment and difficult field operation. The measurement method based on image processing adopted at present cannot meet the actual measurement requirement due to smaller internal stress.
In the prior art, in the patent application with the application number CN202210283531.0 of the application name of 'method and system for measuring the shape and the size of the necking shape of the round bar based on image processing', a round bar test piece is subjected to a monotone tensile test on a material testing machine, image data in the test process are acquired, and analysis is carried out according to the acquired image data. However, such a method is not based on a test piece but a real work piece, and cannot measure actual stress of a welded work piece in situ.
In the prior art, application number CN202211030653.5 is named as a stress measuring method and a stress measuring device, based on the coupling between an optical fiber and a molten part, the stress of a coupling part is obtained through optical index detection of the optical fiber, the layout setting and the coupling process of the optical fiber are complex, and the implementation is difficult under the condition of complex working conditions.
How to design a welding stress measuring method and a system which can be used for a long time in the welding process and in the post-welding maintenance period and are more efficient and convenient is a technical problem to be solved.
Disclosure of Invention
In the application, the applicant proposes to establish a method and a system for measuring the welding stress of a steel bridge based on image processing, and a complete bridge welding stress measuring method is formed by collecting partial pictures before and after welding and combining an elastic plate unit finite element analysis method by utilizing an image processing technology, so that the construction requirements of bridge construction of a steel structure are met.
The technical scheme for solving the technical problems is that the welding stress measuring method based on image processing is used for constructing a 3D model of a welding workpiece; a welding structure finite element analysis model is established on the basis of the 3D model; marking more than two marks for the welding workpiece, and inputting the positions and the sizes of the marks into a 3D model; photographing the mark before welding to obtain a picture, and establishing a relation between a 3D model and the picture; photographing the mark after welding to obtain a post-welding picture, obtaining deformation characteristics of the 3D model according to the mark change in the post-welding picture, and inputting the deformation characteristics into a finite element analysis model; the weld stress variation is calculated.
The welding stress measuring method based on image processing comprises the following optional characteristics: TA10, engraving the mark on the workpiece by laser; TA20, the mark is punched on the workpiece through proofing and punching.
Photographing the mark before and during welding.
The welding stress measuring method based on image processing comprises the following optional characteristics: TB10, the said label array is arranged, label is circular, the diameter is greater than 1mm, smaller than 20mm; the center distance of the marks is more than 5mm and less than 30mm; TB20, the said label array is arranged, label is square, the side length, greater than 1mm, smaller than 20mm; the center distance of the marks is more than 5mm and less than 30mm.
The array is distributed over the welding surfaces of two or more welding workpieces.
The technical scheme for solving the technical problems can also be a welding stress measurement system based on image processing, which comprises a laser engraving unit, a camera shooting unit, an engraving and camera shooting position driving unit and a graph analysis unit; constructing a 3D model of a welding workpiece before welding; a welding structure finite element analysis model is established on the basis of the 3D model; before welding, marking more than two marks on a welding workpiece by a laser engraving unit, shooting mark positions by a camera unit, inputting the mark positions and the sizes into a 3D model, and establishing a relation between the 3D model and a picture; after welding, the camera shooting unit shoots the marks to obtain a welded picture, the graphic analysis unit obtains deformation characteristics of the 3D model according to the mark change in the welded picture, and the deformation characteristics are input into the finite element analysis model; the weld stress variation is calculated.
Before welding, the object distance and the magnification of the camera unit are fixedly set, the size of the marks in the picture is measured, and the distance between the marks is calculated according to the imaging ratio; after welding, the dimensions of the variation in space are obtained, and the variation structure of the 3D model is calculated.
The engraving and shooting position driving unit comprises an X-axis moving module and a Y-axis moving module; the Y-axis moving module is arranged on the X-axis moving module; the laser engraving unit is arranged on the Y-axis moving module; the camera shooting unit is arranged on the Y-axis moving module.
The welding stress measurement system based on image processing also comprises a network unit and a server, wherein the server comprises a server network unit; the graphic analysis unit is positioned on the server; and the identification picture is sent to the server through a network unit.
The welding stress measurement system based on image processing further comprises an installation fixing device, and the carving and shooting position driving unit is positioned on the installation fixing device and comprises any of the following characteristics: TC10: the installation fixing device comprises a screw connecting hole, and is connected to the welding piece through a screw; TC20: the installation fixing device comprises a magnet, and the installation fixing device is adsorbed to the welding piece through the magnet.
One of the technical effects of the technical scheme is as follows: marking more than two marks on a welded workpiece, and photographing the marks after welding; and analyzing the welding stress change of the workpiece according to the relative position change of the marks before and after welding. By means of the mark, stress change information can be obtained through photographing, strain gauges or other sensing mechanisms are not required to be arranged for stress obtaining, and the method is an efficient and convenient stress measuring method without direct contact.
One of the technical effects of the technical scheme is as follows: the mark is engraved on the workpiece by laser, the laser engraving precision is enough, the energy density is high, and the mark on various welding metals is easy to realize.
One of the technical effects of the technical scheme is as follows: the mark is punched to the workpiece through the proofing punch hole, the mark implementation mode is simple and low in cost, and the fixability and the precision of the mark are easier to realize.
One of the technical effects of the technical scheme is as follows: and photographing the mark before and during welding, photographing the whole process before and after welding and during welding, and analyzing the welding stress with higher real-time performance.
One of the technical effects of the technical scheme is as follows: the marks are arranged in an array, are circular, and have diameters larger than 1mm and smaller than 20mm; the center distance of the marks is more than 5mm and less than 30mm; the marks arranged in an array can acquire stress information through the size change of a single mark, and can acquire stress information through the relative position relation among the marks. The mark is circular, marking is convenient, and the size can be adjusted according to the size of an actual workpiece. The mark is circular, and radial deformation is more easily reflected.
One of the technical effects of the technical scheme is as follows: the identification arrays are arranged, the identification is square, the side length is more than 1mm and less than 20mm; the center distance of the marks is more than 5mm and less than 30mm. The mark is square, and deformation in the X axis and the Y axis is more easily reflected.
One of the technical effects of the technical scheme is as follows: the array is distributed on the welding surfaces of two or more welding workpieces, and the welding stress change information between the two welding workpieces can be obtained by distributing the array.
One of the technical effects of the technical scheme is as follows: the carving and shooting position driving unit drives the laser carving unit to mark the welding workpiece with more than two marks; the laser engraving unit and the camera shooting unit share one engraving and camera shooting position driving unit, and can shoot while engraving the mark, so that the cost of moving parts is saved, the synchronism and consistency of the moving parts are improved, and the measurement error caused by adopting two moving parts is avoided.
One of the technical effects of the technical scheme is as follows: the carving and shooting position driving unit comprises an X-axis moving module and a Y-axis moving module, can perform two-dimensional movement in two directions, can perform two-dimensional array identification on a welding surface, and can acquire identification and pictures of a plurality of points.
One of the technical effects of the technical scheme is as follows: setting a network unit and a server, wherein the graphic analysis unit is positioned on the server; the identification picture is sent to the server through the network element. The setting of the server can improve the data collection and operation capability of the graphic analysis unit, can perform stress analysis more rapidly, can collect various stress data, enrich the content of an actual stress database, and therefore improve the accuracy of stress analysis.
One of the technical effects of the technical scheme is as follows: the camera shooting unit is arranged on the Y-axis moving module, the camera shooting unit and the laser engraving unit are driven to move, and the relative positions of the camera shooting unit and the laser engraving unit are fixed, so that consistency between the positions of the engraving marks and the positions of the marks in the pictures is higher, and the position accuracy of the marks in the pictures are higher.
One of the technical effects of the technical scheme is as follows: the carving and shooting position driving unit is located on the installation fixing device, the installation fixing device comprises a screw connection hole, and the installation fixing device is connected to the welding piece through screws. The method is very flexible, and the installation fixing device can be conveniently arranged in the production or maintenance process of the workpiece, so that space and position are provided for the installation of the carving and shooting position driving unit. The mode can be conveniently detached, is convenient to install when detection is needed, and can be flexibly detached when detection is not needed. And can be installed laterally generally without affecting the position of the workpiece or the welding operation.
One of the technical effects of the technical scheme is as follows: when the weldment is made for the material that has magnetic force adsorption characteristic, installation fixing device includes magnet, and installation fixing device adsorbs on the weldment through magnet, and such mode further lets the installation with dismantle installation fixing device becomes more convenient high-efficient.
One of the technical effects of the technical scheme is as follows: and the precision of the relative displacement variation is improved through a plurality of pictures in different positions or directions.
Drawings
FIG. 1 is one of the schematic block diagrams of an image processing based welding stress measurement system;
FIG. 2 is a second schematic block diagram of an image processing based welding stress measurement system;
FIG. 3 is a third schematic block diagram of an image processing based welding stress measurement system;
FIG. 4 is one of the perspective views of two welded workpieces respectively labeled with more than two identifiers;
FIG. 5 is a second perspective view of two workpieces being welded with two or more labels;
FIG. 6 is a schematic front elevational view of two welded workpieces respectively labeled with more than two identifiers;
FIG. 7 is one of the perspective views of the connection of two welding workpieces and a mounting fixture;
FIG. 8 is one of the perspective views of the mounting fixture attachment;
FIG. 9 is a second perspective view of the attachment of the mounting fixture;
FIG. 10 is a schematic illustration of an application scenario of an image processing based welding stress measurement system;
FIG. 11 is a schematic diagram of a finite element analysis model of a large bridge structure;
FIG. 12 is a deformation profile of a line before and after welding of the large bridge structural member of FIG. 11;
FIG. 13 is a schematic diagram of the magnitude of internal stress of a finite element analysis model.
Detailed Description
The present application is described in further detail below in conjunction with the various figures.
It should be noted that the following description is a description of the preferred embodiments of the present application, and is not meant to limit the present application. The description of the preferred embodiments of the present application is provided only as an illustration of the general principles of the present application. The embodiments described in this application are only some, but not all, of the embodiments of this application. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present disclosure.
In the description of the present application, it should be understood that the terms "center," "longitudinal," "transverse," "length," "width," "thickness," "up," "down," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," etc. indicate orientations or positional relationships based on the orientation or positional relationships shown in the drawings are merely for convenience in describing the present application and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present application. Furthermore, the terms "first," "second," and technical features numbered with numerals such as Arabic numerals 1, 2, 3, etc., and such numbers as "A" and "B" are used for descriptive purposes only and are not intended to represent a temporal or spatial sequential relationship for ease of illustration; and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, features defining "first", "second", and numbered with numerals 1, 2, 3, etc., may explicitly or implicitly include one or more such features. In the description of the present application, the meaning of "a number" is two or more, unless explicitly defined otherwise.
As shown in fig. 1 to 3, in an embodiment of the welding stress measuring system based on image processing, a laser engraving unit, a camera shooting unit, an engraving and camera shooting position driving unit, and a graphic analysis unit are included; constructing a 3D model of a welding workpiece before welding; a welding structure finite element analysis model is established on the basis of the 3D model; before welding, marking more than two marks on a welding workpiece by a laser engraving unit, shooting mark positions by a camera unit, inputting the mark positions and the sizes into a 3D model, and establishing a relation between the 3D model and a picture; after welding, the camera shooting unit shoots the marks to obtain a welded picture, the graphic analysis unit obtains deformation characteristics of the 3D model according to the mark change in the welded picture, and the deformation characteristics are input into the finite element analysis model; calculating the welding stress change; the carving and shooting position driving unit drives the laser carving unit to mark the welding workpiece with more than two marks; before or after welding, the camera shooting unit shoots the mark to obtain a mark picture; the graph analysis unit analyzes the welding stress change of the workpiece according to the relative position change of the marks before and after welding.
As shown in fig. 1 to 3, in an embodiment of the welding stress measuring system based on image processing, the carving and photographing position driving unit includes an X-axis moving module and a Y-axis moving module; the Y-axis moving module is arranged on the X-axis moving module; the laser engraving unit is arranged on the Y-axis moving module.
As shown in fig. 1 to 3, in an embodiment of the welding stress measurement system based on image processing, the welding stress measurement system further comprises a network unit and a server, wherein the server comprises a server network unit; the graphic analysis unit is positioned on the server; and the identification picture is sent to the server through a network unit.
As shown in fig. 1 to 3, in the embodiment of the welding stress measuring system based on image processing, the image capturing unit is disposed on the Y-axis moving module.
As shown in fig. 4 to 5, in the bridge of fig. 10, two welded workpieces 100 are respectively marked with two or more marks 200. As shown in fig. 4 to 5, the marks are arranged in an array, are circular, and have diameters larger than 1mm and smaller than 20mm; the center distance of the marks is more than 5mm and less than 30mm. A first mark 110 is provided on one side of the first welding workpiece 100; a second identifier 120 is provided on one side of the second weld workpiece 120. The first and second markers 110 and 120 are each provided in a circular shape.
In some embodiments of the welding stress measurement method and system based on image processing, which are not shown in the drawings, the identification arrays are arranged, and the identification arrays are square, have side lengths of more than 1mm and less than 20mm; the center distance of the marks is more than 5mm and less than 30mm.
As shown in fig. 7 to 9, in the embodiment of the welding stress measuring system based on the image processing, a mounting fixture 300 is further included, and the engraving and photographing position driving unit 500 is located on the mounting fixture 300. The mounting fixture includes screw connection holes 310 through which the mounting fixture is connected to the weldment 100.
In some embodiments of the image processing based welding stress measurement system not shown in the drawings, the mounting fixture 300 includes a magnet by which the mounting fixture is attracted to the weldment.
Some embodiments of the image processing-based welding stress measurement method not shown in the drawings include the steps of constructing a 3D model of a welded workpiece; a welding structure finite element analysis model is established on the basis of the 3D model; marking more than two marks for the welding workpiece, and inputting the positions and the sizes of the marks into a 3D model; photographing the mark before welding to obtain a picture, and establishing a relation between a 3D model and the picture; photographing the mark after welding to obtain a post-welding picture, obtaining deformation characteristics of the 3D model according to the mark change in the post-welding picture, and inputting the deformation characteristics into a finite element analysis model; the weld stress variation is calculated. Before welding, the object distance and the magnification of the camera unit are fixedly set, the size of the marks in the picture is measured, and the distance between the marks is calculated according to the imaging ratio; after welding, the dimensions of the variation in space are obtained, and the variation structure of the 3D model is calculated.
Marking more than two marks on a welding workpiece; photographing the mark after welding; and analyzing the welding stress change of the workpiece according to the relative position change of the marks before and after welding. In an embodiment of the method for measuring welding stress based on image processing, the marking is engraved to the workpiece by means of a laser. In embodiments of the image processing based welding stress measurement method not shown in other figures, the marks are punched into the workpiece by proofing punch holes. Photographing the mark before and during welding.
Fig. 11 is a structural member in the process of building a real large bridge, fig. 11 is a finite element analysis model based on a 3D model, and fig. 12 is deformation data before and after welding of a side line4 in fig. 11, wherein the deformation size has a change of about 0.2 mm in the Z direction.
The pixel size of a modern camera is about 70 micrometers, deformation of about 0.1 millimeter is resolved through lens imaging, the range and the direction of the pattern deformation of the surface of a weldment are limited in the welding process, the transformation of a two-dimensional picture is calculated and projected to a 3-dimensional structure to be limited, namely, the deformation size of a 3-dimensional model can be accurately obtained based on the pattern deformation of the surface of the weldment. The method greatly reduces the mapping difficulty on site, and the engineering practice proves that the method is efficient, quick and low in cost, and can be widely popularized and applied.
Fig. 13 is an internal stress variation calculated by a finite element analysis model to rapidly evaluate weld quality.
The invention forms a set of testing technology suitable for the internal stress of a steel bridge structure, which comprises the following specific steps: marking a surface to be measured with marks of standard sizes; acquiring pictures before and after welding, measuring and obtaining the relative displacement variation before and after welding by means of the mapping from a 2-dimensional image to a 3-dimensional model by means of the correlation of mark points of a reference scale, and improving the precision of the relative displacement variation by means of a plurality of pictures in different positions or directions; and finally obtaining internal stress data of the structure by combining boundary conditions through an elastic finite element analysis method.
While this application has been illustrated and described in terms of a preferred embodiment and several alternatives, the application is not limited by the specific description in this specification. Other additional alternative or equivalent components may also be used in the practice of the present application.
Claims (10)
1. A welding stress measuring method based on image processing is characterized in that,
constructing a 3D model of the welding workpiece; a welding structure finite element analysis model is established on the basis of the 3D model;
marking more than two marks for the welding workpiece, and inputting the positions and the sizes of the marks into a 3D model;
photographing the mark before welding to obtain a picture, and establishing a relation between a 3D model and the picture;
photographing the mark after welding to obtain a post-welding picture, obtaining deformation characteristics of the 3D model according to the mark change in the post-welding picture, and inputting the deformation characteristics into a finite element analysis model; the weld stress variation is calculated.
2. The method for measuring welding stress based on image processing according to claim 1, wherein,
comprising any of the following features:
TA10, engraving the mark on the workpiece by laser;
TA20, the mark is punched on the workpiece through proofing and punching.
3. The method for measuring welding stress based on image processing according to claim 1, wherein,
and photographing the mark before and during welding, wherein photographing is performed at different positions or in different directions.
4. The method for measuring welding stress based on image processing according to claim 3, wherein,
comprising any of the following features:
TB10, the said label array is arranged, label is circular, the diameter is greater than 1mm, smaller than 20mm; the center distance of the marks is more than 5mm and less than 30mm;
TB20, the said label array is arranged, label is square, the side length, greater than 1mm, smaller than 20mm; the center distance of the marks is more than 5mm and less than 30mm.
5. The method for measuring welding stress based on image processing according to claim 1, wherein,
the array is distributed over the welding surfaces of two or more welding workpieces.
6. A welding stress measurement system based on image processing is characterized in that,
the device comprises a laser engraving unit, a camera shooting unit, an engraving and camera shooting position driving unit and a graph analysis unit;
constructing a 3D model of a welding workpiece before welding; a welding structure finite element analysis model is established on the basis of the 3D model;
before welding, marking more than two marks on a welding workpiece by a laser engraving unit, shooting mark positions by a camera unit, inputting the mark positions and the sizes into a 3D model, and establishing a relation between the 3D model and a picture;
after welding, the camera shooting unit shoots the marks to obtain a welded picture, the graphic analysis unit obtains deformation characteristics of the 3D model according to the mark change in the welded picture, and the deformation characteristics are input into the finite element analysis model; the weld stress variation is calculated.
7. The image processing based weld stress measurement system of claim 6, wherein,
before welding, the object distance and the magnification of the camera unit are fixedly set, the size of the marks in the picture is measured, and the distance between the marks is calculated according to the imaging ratio;
after welding, the dimensions of the variation in space are obtained, and the variation structure of the 3D model is calculated.
8. The image processing based weld stress measurement system of claim 6, wherein,
the engraving and shooting position driving unit comprises an X-axis moving module and a Y-axis moving module;
the Y-axis moving module is arranged on the X-axis moving module; the laser engraving unit is arranged on the Y-axis moving module;
the camera shooting unit is arranged on the Y-axis moving module.
9. The image processing based weld stress measurement system of claim 6, wherein,
the system also comprises a network unit and a server, wherein the server comprises a server network unit;
the graphic analysis unit is positioned on the server;
and the identification picture is sent to the server through a network unit.
10. The image processing based weld stress measurement system of claim 6, wherein,
the engraving and shooting position driving unit is positioned on the mounting and fixing device and comprises any of the following characteristics:
TC10: the installation fixing device comprises a screw connecting hole, and is connected to the welding piece through a screw;
TC20: the installation fixing device comprises a magnet, and the installation fixing device is adsorbed to the welding piece through the magnet.
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| CN202311791395.7A CN117548869A (en) | 2023-12-25 | 2023-12-25 | Welding stress measurement method and system based on image processing |
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