CN1909020A - Argon-arc welding operation analog training device - Google Patents

Abstract

The invention relates to a welding operation simulation training device, in particular to argon arc welding welding operation simulation training device, which includes a simulation welding torch, a simulation welding wire, and a simulation test piece, and is characterized in that it also includes a main control computer, a simulation welding torch and a welding wire position detection device, and a helmet with a display, the main control computer is also connected with the display on the helmet so that a corresponding picture is displayed on the display according to the welding process, an arc ignition switch is installed on the simulated welding torch, and the present invention is aimed at argon arc welding There are several problems in the actual welding training stage, change the previous training method, adopt a new type of simulated welding torch, wear a special welding helmet to simulate the welding process, and achieve the purpose of quickly cultivating the welder's operating feel and reducing material and energy consumption. The simulated welding torch can simulate the process of argon arc welding, welding wire filling and arc burning. The real scene of the welding process is displayed to the welder through the helmet display.

Description

Argon arc welding operation simulation training device

technical field

The invention relates to a welding operation simulation training device, in particular to argon arc welding welding operation simulation training device.

Background technique

Welding is a very popular material processing method. It is widely used in various enterprise production occasions. Typical examples are automobile manufacturing, pressure vessel manufacturing, shipbuilding, etc. Although there are many automatic welding methods that are relatively mature and more and more applied. However, due to the convenience and flexibility of use, manual welding methods such as argon arc welding still have an irreplaceable role, such as welding of various pressure vessel pipes and various maintenance welding occasions.

In the manual welding operation process, there are many factors that affect the welding quality, such as the selection of process parameters such as: current, voltage, electrode (welding wire) selection, etc.; argon arc welding also has gas flow, tungsten electrode diameter, etc. In addition, the operation process Some parameters also have a great influence on welding quality, such as: welding speed, stability of arc length, swing range of electrode, etc. The stability of the welding process directly affects the welding quality. This is a completely human factor, which depends entirely on the skills and experience of the welding operator. In the control of welding quality, the current, voltage, preheating temperature, and drying degree of the electrode These process parameters can be controlled through process documents and measurement technology, but parameters related to human operation, such as welding speed and welding posture, cannot be recorded and controlled. In order to train good welding skills, it takes hard work and considerable economic cost, so as to master the real feeling of the manual welding process. Training welders is a process that requires a lot of time and consumes a lot of electric energy and welding materials. In the actual training stage of manual welding in the past, the training was carried out by the master leading the apprentice. The training effect was affected by human factors such as the teacher's operation level and expression ability, and the shortage of teachers has already appeared in the current welding training field. At the same time, the welding operation also has high requirements on the site, equipment and environment. The training process needs to consume a lot of welding rods, test plates, and considerable power resources. Not only that, but as we all know, the welding environment is relatively harsh. A large amount of smoke and dust and strong arc light are very likely to have adverse effects on the health of welders. For new welding personnel, the harsh working environment is likely to have a negative impact on their psychology, which is not conducive to follow-up training plans.

Chinese invention patent application CN 1469097A (application number 03110000.7) and invention patent application CN 1439149A (application number 01811824.0) disclose the simulated training system of shoulder-launched air defense missile and dentistry respectively.

Contents of the invention

The object of the present invention is to provide a simulation training device for argon arc welding operation with high simulation degree, low requirements on site and environment, less material and energy consumption, and easy for welding operation training for welders.

In order to achieve the above object, the technical scheme adopted in the present invention is:

A kind of argon arc welding welding operation simulation training device, including simulated welding torch, simulated welding wire, and simulated test piece, and its special feature is that it also includes a main control computer, simulated welding torch and welding wire position detection device, and a helmet with a display, Wherein the simulated welding torch and the welding wire position detection device are connected with the main control computer to provide the spatial position information of the simulated welding torch and the simulated welding wire, and the main control computer is also connected with the display on the helmet to display corresponding pictures on the display according to the welding process; An arc ignition switch is installed on the simulated welding torch, and the arc ignition switch is connected with the main control computer so as to provide it with an arc ignition start signal.

Wherein said display is a liquid crystal display.

The simulated welding torch and welding wire position detection device includes at least two CCD cameras arranged in parallel, and the CCD cameras are connected to the main control computer through an image acquisition card.

Further, at least two light emitting diodes are installed on the simulated welding torch, and at least one light emitting diode is installed on the simulated welding wire.

The invention aims at several problems existing in the actual training stage of argon arc welding, changes the previous training method, adopts a new type of simulated welding torch, and wears a welding special helmet to simulate the welding process, so as to quickly cultivate the welder's operating feel and reduce materials and energy For the purpose of consumption, a new type of simulated welding torch can be used to simulate the process of argon arc welding, welding wire filling and arc burning. The real scene of the welding process is displayed to the welder through the helmet display. In the process of welding operation training, this system has the following characteristics:

(1) The weight and volume of the simulated welding torch are consistent with those commonly used in argon arc welding, providing welders with the same feel as the actual welding torch;

(2) The helmet-mounted display is transformed from a welder's special helmet, and the wearing feeling is consistent with the real welding process;

(3) The arc striking action of argon tungsten arc welding adopts the high-frequency arc striking method similar to that on the real welding torch, and uses high-frequency voltage to penetrate the air to strike the arc, which is controlled by the arc striking switch on the simulated welding torch;

(4) The welding scene changes with the change of the preset welding specification parameters. When the welding current, voltage, tungsten electrode size, gas flow and other parameters change, the scene observed by the welder also changes accordingly, which can be simulated as realistically as possible Real welding process.

The present invention designs a simulation training device for argon tungsten arc welding on the basis of the existing argon tungsten arc welding welding principle and realization process. The operation training of argon tungsten arc welding can be realized on this device. Smoke, dust and strong light in the real welding process, but you can also feel the real welding process in the virtual scene. To this end, a new type of argon tungsten arc welding simulation torch is designed, which realizes the simulation process of argon tungsten arc welding out of the real welding environment. Through simulated operation training, you can not only feel the welding process, master the welding feel, improve welding skills, but also greatly reduce training costs and improve training efficiency. At the same time, the training process is completely safe for welders. It is foreseeable that this is a kind of breaking the routine Safe and efficient training methods.

Description of drawings

Accompanying drawing 1 is the overall principle block diagram of the present invention;

Accompanying drawing 2 is the equipment connection schematic diagram of the present invention;

Accompanying drawing 3 is the structural representation of simulation torch among the present invention;

Accompanying drawing 4 is the pinhole imaging model schematic diagram of CCD camera imaging system among the present invention;

Accompanying drawing 5 is the binocular imaging model schematic diagram of CCD camera imaging system among the present invention;

Accompanying drawing 6 is the image detection program flowchart of CCD imaging system among the present invention;

Accompanying drawing 7 is the schematic diagram of the helmet with display;

Accompanying drawing 8 is the control flowchart of the main program of the present invention.

Detailed ways

The present invention will be described in further detail below in conjunction with accompanying drawing:

The present invention adopts virtual reality technology as the core of the platform. In essence, virtual reality is an advanced computer user interface. , To maximize the convenience of the user's operation, thereby reducing the burden on the user and improving the work efficiency of the entire system. Usually the user wears a headset (a head-mounted display used to display stereoscopic images) and holds a sensory glove, as if in a hallucinatory world, roaming in the virtual environment and allowing the manipulation of "objects" in it.

The welding operation simulation training device of the present invention is aimed at the cultivation of the operation feel in the argon arc welding process. The tools used in welder training, such as simulated welding torches and helmets, should be as consistent as possible with those used in real welding, so that it can ensure that the welder is in the same position during welding. The operating habits and operating feel developed during the simulation training are the same as those in real welding. Moreover, it is necessary to reconstruct a realistic three-dimensional scene for them according to the welder's operation process. In this three-dimensional scene, the welding situation reflected is in one-to-one correspondence with the welder's operation process. For example: during argon arc welding, the welder needs to fill the welding wire into the arc from the side. If it is not fed in time, the welding wire will not be able to melt, resulting in defects in the formation of the weld. In the virtual three-dimensional scene, the appearance of the arc and the formation of the weld should conform to such laws. According to the observation of the stability of the arc, the welder can find out the problems in the operation in time and adjust the position of the welding wire in time, so as to develop good operating habits and technique.

In order to obtain the positions of the simulated welding torch and the simulated welding wire, the present invention mainly adopts the method of image detection. The images in the training process are taken simultaneously by two CCD cameras. The feature points of the position are synthesized according to the three-dimensional coordinates of the two images, and then the computer uses the OpenGL interface to simulate the three-dimensional welding scene in real time according to the synthesized three-dimensional coordinates. In order to make the program processing simple and fast, two light-emitting diodes (bright spots) are set on the simulated welding torch, and one light-emitting diode (bright spot) is set on the simulated welding wire. The purpose is to find the simulated welding torch and simulated The position of the welding wire.

Fig. 1 is the overall principle block diagram of the present invention, is made up of two big modules of hardware and software, and the main function of hardware part is to simulate welding process, cultivate operation feel; Interactive, the welder's operation process will be truly reflected in the three-dimensional scene, and the scene provides the same scenes as the real welding process, such as arc light, welding wire melting, molten pool formation, etc. These scenes are controlled by the main control computer according to the welder's pre-set process Parameters and collected welder operation actions are generated in real time.

Fig. 2 is the equipment connection schematic diagram of the present invention, can see from the figure, the hardware part is mainly made up of following several parts: argon tungsten arc welding simulation torch, simulation test piece, helmet with display, main control computer, CCD Video cameras, etc., can also include analog consoles and some auxiliary equipment. The camera adopts the MTV 1881 EX black and white CCD camera of Taiwan Mintong, and the image acquisition card adopts the M10 card of Beijing Weishi Company.

Fig. 8 is a control flow chart of the main program of the present invention, and the present invention adopts this mode to display images and save data.

The function and implementation technology of each component will be introduced in detail below.

1. Structural design of argon tungsten arc welding simulation torch

As shown in Figure 3, the design of the argon tungsten arc welding torch takes into account the difference between argon tungsten arc welding and manual arc welding, and the structure is simpler, which is a simulated welding torch and welding wire. In the feeding process, the welding wire is manually filled from the side, so the structure of the welding torch does not need the same power system as manual arc welding when simulating argon arc welding. The main purpose of designing the simulated welding torch is to enable the CCD imaging system to detect the position of the simulated welding torch and the simulated welding wire. This is achieved by modifying the existing argon arc welding torch and welding wire. The simulated test piece can be a simulated piece or a real test piece. pieces.

The key to detecting the spatial position of the simulated welding torch is to detect the distance between the tungsten electrode and the simulated specimen and the inclination angle of the simulated welding torch. The detection method is to set two light-emitting diodes on the simulated welding torch, one of which is at the position of A light-emitting diode is set on the welding wire, and two CCD cameras placed in parallel realize the three-dimensional coordinate detection of the spatial position of the simulated welding torch and the simulated welding wire.

2. Realization process of argon tungsten arc welding simulation

The welding process of argon tungsten arc welding is composed of three parts: arc ignition, welding (arc movement) and arc closing. The arc ignition method of argon arc welding generally adopts high-frequency arc ignition, that is, through the welding torch between the tungsten electrode and the specimen. Apply a high-frequency voltage to break down the air, ionize the air, and ignite the arc. The welding process of argon arc welding is generally that the welder holds the welding torch in one hand to keep the arc burning stably, holds the welding wire in the other hand, observes the arc burning situation through goggles, puts the welding wire in the arc, and melts the welding wire by the high temperature of the arc, dripping into the molten pool Form the weld seam.

(1) Simulation of arc striking process

Different from manual arc welding, argon tungsten arc welding generally does not use short-circuit contact arc ignition, so the arc ignition simulation of argon arc welding is simpler than manual arc welding. The image of the arc in the scene appears. When the arc ignition switch is closed, the main control computer detects the state of the arc ignition switch, combined with the image detection results, and when the simulated welding torch is raised within a suitable range, the arc will start normally in the virtual scene. If the arc ignition switch is not turned on or the simulated torch lifting height is not within the normal range, the arc cannot be ignited.

(2) Simulation of welding process

The simulation of the welding process is carried out on the basis of the continuous detection of the posture of the simulated welding torch by the image detection program. As the welding progresses, the change of the spatial position of the simulated welding torch will be reflected in the virtual scene. Different from manual arc welding, the simulation of argon tungsten arc welding not only needs to detect the position of the simulated welding torch, but also needs to detect the position of the simulated welding wire. In this way, a total of three points need to be detected by the CCD camera. Only when the welding wire is in the arc, can it be melted by the high temperature of the arc, and when the welding wire is not in the arc, the welding wire will not be melted, and the shape of the weld will be affected, and the main control computer will simulate accordingly.

3. The principle of image method to detect the spatial position of bright spots

At present, the perspective imaging model of the CCD imaging system mostly adopts the pinhole imaging model, and the pinhole model reflects the positional relationship between the imaging point of the spatial point on the camera array and the optical center of the camera.

As shown in Figure 4, the pinhole imaging model shows that the imaging point of a spatial point M on the CCD camera array is the intersection point m of the line connecting the spatial point M and the optical center point O of the camera on the CCD array, and the spatial point on the camera The imaging on is only one point. It can be seen from the imaging model that as long as it is a point on the line of OM, the imaging point on the CCD array is m, and it can only be determined that point M is located on the extension line of Om. Therefore, the coordinate position of the spatial point M cannot be inferred from the image captured by a single camera. It can be seen that in order to determine the spatial position of a point, at least two cameras are required for detection.

Fig. 5 is a schematic diagram of the binocular imaging model of the CCD camera imaging system in the present invention. In the figure, m1 and m2 are the imaging positions of the spatial point M on the two CCD cameras respectively. As can be seen from Figure 5, the position of the spatial point M is determined by its imaging point on the front of the two CCD cameras and the optical parameters of the CCD camera. Intersect the lines connecting the center points to get. This imaging mode is similar to the binocular vision of human beings. By observing with two eyes and reflecting the image to the brain, one can feel the spatial position of the object.

Fig. 6 is the image detection program flowchart of CCD imaging system among the present invention, can finish the detection of the spatial position of bright point (being the light-emitting diode on the simulation welding torch and simulation welding wire) accordingly, also just reflected simulation welding torch and simulation welding wire simultaneously spatial location.

4. The structure of the helmet with the display

The main functions of the helmet with a display are: (1) to truly reflect the helmet protection equipment worn by the welder during welding, and the wearing feeling (such as shape, weight, etc.) should be as close as possible to the actual welding; (2) to be able to display the three-dimensional scene generated by the computer, Through the display, the welder can observe the real process of his own welding operation, and can obtain the information given by the system on the display to indicate the next operation. Figure 7 is a schematic diagram of a helmet with a display.

In the present invention, a real welding protective face shield has been selected as the base body of the helmet display, so that the feeling of the face shield worn when wearing the helmet and welding is relatively close, and the liquid crystal display is selected for use in the display, although the liquid crystal display and the driving circuit rear mask are added. The weight and the position of the center of gravity have changed, but it is possible to add a support frame inside or add a suspension device to the platform to reduce the wearer's discomfort.

The display of the scene is realized by adding an LCD screen on the mask. The LCD display image is delicate, small in size and light in weight. The biggest advantage is that there is no radiation and no flicker, which is very good for protecting the welder's eyes. The size of the LCD screen is 6 inches, and the display resolution is 640×480. The display effect can meet the requirements of the simulation platform. The LCD screen is installed at the position of the goggles in front of the welder's mask. By adjusting the distance between the LCD screen and the mask, the position of the welder's eyes from the LCD screen can be changed when observing. Only by maintaining an appropriate viewing distance can the fatigue of the welder's eyes be reduced.

Using the simulated welding torch of the present invention for argon arc welding operation training can quickly cultivate the welder's operating feel, and because the simulated welding torch can simulate the same arc striking and welding process as the actual welding, the welder can use the simulated welding torch. Exercise welding wire feeding and moving welding torch and other actions. After using the simulated welding torch, it will greatly save the materials and electric energy consumed by welding, and greatly reduce the training cost, and the use of the simulated welding torch is not limited by the site, no special welding machine, no supporting equipment such as gas cylinders, and it is convenient for multiple people at the same time Operation training. The trainer will be freed from the heavy work, and only needs to give guiding opinions to the welder, and the welder will experience the feel and operation skills of the welding process over and over again. During the simulation training process, there is no smoke, no strong light, no high temperature , will not cause physical harm to the welder, nor will it cause psychological boredom.

In order to support the training of actual welding operations, there can also be a supporting multimedia welding theory training system in the software system of the simulation platform, so that welders can combine theory with practice, verify and compare each other, and improve the efficiency of training.

Attachment: References on the implementation of virtual reality using OpenGL

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[3] Li Qing, Shanyao, Chen Yijun. Research on Real-time Battlefield Command System Based on Virtual Reality Technology. Computer Simulation [J]. 2005.22(9): 12-14.

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Claims (4)

1, a kind of argon-arc welding operation analog training device comprises simulated welding gun, simulation welding wire and imitation specimen, it is characterized in that:

Also comprise main control computer, simulated welding gun and welding wire position detecting device and have the helmet of display, wherein thereby simulated welding gun and welding wire position detecting device are connected the spatial positional information that simulated welding gun and simulation welding wire are provided to it with main control computer, thereby main control computer also is connected according to welding process with display on the helmet demonstrates corresponding picture on display;

The striking switch is installed, thereby this striking switch is connected to it with main control computer the striking commencing signal is provided on described simulated welding gun.

2, argon-arc welding operation analog training device as claimed in claim 1 is characterized in that: wherein said display is a LCD.

3, argon-arc welding operation analog training device as claimed in claim 1, it is characterized in that: wherein simulated welding gun and welding wire position detecting device comprise at least 2 ccd video cameras that be arranged in parallel, and ccd video camera is connected to main control computer by image pick-up card.

4, argon-arc welding operation analog training device as claimed in claim 3 is characterized in that: at least 2 light emitting diodes are installed on described simulated welding gun, on described simulation welding wire at least 1 light emitting diode are installed.

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