Real-time control method for transverse wire feeding position of wire GTAW based on visual sensing

Abstract

The present application relates to a kind of based on visual sensing's wire filling GTAW transverse wire filling position real-time control method.Utilize visual sensor real-time acquisition welding arc image in welding process;With the transverse distance calculation method of arc axis and wire axis, the transverse position of wire in arc is detected in real time;With wire transverse adjusting mechanism, wire transverse position is regulated in real time;With wire transverse automatic adjusting method, wire transverse position is controlled to keep wire axis always intersect with arc axis.The present application successfully realizes the accurate identification and regulation of wire filling transverse position in wire filling GTAW process, further improves welding efficiency and quality.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of visual sensing GTAW transverse wire feeding position real-time control, and is a visual sensing GTAW transverse wire feeding position real-time control method. BACKGROUND

[0002] GTAW (Gas Tungsten Arc Welding) is widely used in arc additive manufacturing, aerospace, marine equipment, nuclear power construction, precision instruments and other fields. In recent years, the development of arc additive technology has become increasingly rapid, and the automation and intelligence of GTAW have been increasingly required. In the process of GTAW, the transverse deviation of the welding wire and the arc has a significant impact on the welding efficiency and the weld quality. The intersection of the welding wire axis and the arc axis is conducive to maintaining the stability of the arc and forming a high-quality weld. However, there is currently no method to realize the real-time control of the transverse wire feeding position of GTAW. In view of this problem, the present application discloses a visual sensing GTAW transverse wire feeding position real-time control method. SUMMARY

[0003] The visual sensing GTAW transverse wire feeding position real-time control method is used for real-time feedback and adjustment of the transverse position of the welding wire during the welding process of GTAW, so as to ensure that the welding wire axis always intersects with the arc axis and improve the welding efficiency and quality. The characteristic is that the visual sensing GTAW transverse wire feeding position real-time control method is realized by using a visual sensing GTAW transverse wire feeding position real-time control system, and the system principle diagram is as shown in Figure 1 The visual sensing GTAW transverse wire feeding position real-time control system is composed of a visual sensor, an image information processor, a welding wire transverse position controller, a welding wire transverse adjustment mechanism, a visual sensor position adjustment mechanism, a clamping device, a high-precision wire feeder, a wire feeding pipe and a welding torch. The visual sensor is used to monitor the positions of the welding wire axis and the arc axis in real time, collect real-time images of the welding process by using the visual sensor, and transmit the image information to the image information processor. The image information processor is used to process the image information from the visual sensor, calculate the transverse distance between the welding wire axis and the arc axis by using a welding wire axis and arc axis transverse distance calculation method, and transmit the transverse distance data between the welding wire axis and the arc axis to the welding wire transverse position controller in real time through a communication bus. The welding wire transverse position controller is used to identify the transverse positions of the welding wire axis and the arc axis, and control the welding wire transverse position, so that the welding wire axis always intersects with the arc axis. The visual sensor position adjustment mechanism is used to automatically adjust the position of the visual sensor. The clamping device is used to fix the visual sensor and the wire feeding pipe on the welding torch. The high-precision wire feeder is used to accurately control the wire feeding speed. The wire feeding pipe is used to convey the welding wire.

[0004] The aforementioned real-time control method for the lateral filler wire position in GTAW (Gas-to-Warm) welding based on vision sensing is characterized by: using a vision sensor to acquire real-time images of the welding wire and arc during the welding process; the vision sensor is fixed to the welding torch via a clamping device, with the central axis of the vision sensor and the central axis of the wire feed tube coplanar and distributed on both sides of the welding torch; the clamping device consists of a vision sensor clamping arm and a wire feed tube clamping arm; the vision sensor is connected to a height adjustment slider via an angle adjustment shaft, and the slide rail of the height adjustment slider is connected to the welding torch via the vision sensor clamping arm; before welding begins, the vision sensor transmits image information to an image information processor, which detects whether the centerline of the captured image coincides with the centerline of the arc. If they do not coincide, the angle and height of the vision sensor are adaptively adjusted via the angle adjustment shaft and the height adjustment slider to make the centerline of the image coincide with the centerline of the arc, and to ensure that the image field of view includes both the welding wire axis and the arc axis to monitor the position of the welding wire axis and the arc axis in real time. Figure 2 As shown on the right.

[0005] The aforementioned real-time control method for the lateral position of GTAW filler wire based on vision sensing is characterized by: real-time detection of the lateral position of the filler wire in the arc using a method for calculating the lateral distance between the filler wire axis and the arc axis; the method for calculating the lateral distance between the filler wire axis and the arc axis is a method for processing and calculating the real-time image information captured by the vision sensor through an image information processor, thereby obtaining accurate data on the lateral distance between the filler wire axis and the arc axis; the method for calculating the lateral distance between the filler wire axis and the arc axis utilizes the image information processor to process and calculate the received real-time welding process image. The image is converted to grayscale, and the region of the arc and welding wire is defined. A Gaussian filter is used to filter this region. Finally, a welding wire axis detection algorithm is used to obtain the coordinates of each point on the welding wire axis. These coordinates are the coordinates of each point on the welding wire axis in a Cartesian coordinate system established with the image center as the origin. The welding wire axis detection algorithm first calculates the coordinates of each point on both sides of the welding wire from the end upwards. Then, for two points with the same ordinate, the ordinate is kept unchanged, and the x-coordinate is the midpoint of the two points to obtain the x-coordinate of that point on the axis. Thus, the coordinates (x, y) of each point on the welding wire axis are obtained. n ,y n ).

[0006] The aforementioned vision-sensing-based real-time control method for the lateral position of GTAW filler wire is characterized in that: the lateral adjustment mechanism of the welding wire consists of a high-precision adjustment slider and a driver, used to control the lateral position of the welding wire in real time; the bottom of the high-precision adjustment slider is fixed to the welding torch by a wire feeding tube clamp arm, and the moving part of the high-precision adjustment slider is fixedly connected to the wire feeding tube; the driver is connected to the lateral position controller of the welding wire through a communication bus to receive the displacement and speed parameters of the lateral movement of the welding wire, and drives the high-precision adjustment slider through a control line to control the lateral position of the welding wire in real time.

[0007] The aforementioned real-time control method for the lateral filler position of GTAW based on vision sensing, such as... Figure 3 As shown, the automatic lateral adjustment method for the welding wire is characterized by: identifying and correcting the lateral position deviation of the welding wire to ensure that the welding wire axis always intersects the arc axis; the lateral position controller for the welding wire receives the coordinates (x, y) of each point on the welding wire axis transmitted by the image information processor. n , y n The welding wire lateral position controller determines whether the abscissas of each point on the welding wire axis are the same; if... x1-x2 <α, x1-x3 <α, x1-x4 <α,..., x1-x n <α, where α is the maximum deviation of the horizontal coordinate of the welding wire axis; take the horizontal coordinate x=x1, (x1, y1) as the coordinate of the end of the welding wire axis, and when the end point of the welding wire axis coincides with the arc axis, the welding wire axis intersects the arc axis; when x>ξ, the welding wire lateral position controller sends a command to the driver, causing it to control the high-precision adjusting slider to move the wire feed tube towards the negative half of the x-axis to x=0; when At that time, the wire lateral position controller sends a command to the driver, which controls the high-precision adjusting slider to move the wire feeding tube towards the positive half of the x-axis to x=0; The experiment was conducted to determine the maximum lateral deviation of the welding wire while ensuring good welding quality.

[0008] Beneficial effects of the invention

[0009] The present application relates to a kind of based on visual sensing's wire filling GTAW transverse wire filling position real-time control method.Wire and arc real-time image in welding process is collected using visual sensor;Wire in arc in transverse position is detected in real time using the transverse distance calculation method of wire axis and arc axis;Wire transverse adjusting mechanism is used to control wire transverse position in real time;Wire transverse position is controlled using wire transverse automatic adjusting method to keep wire axis always intersect with arc axis.The present application successfully realizes accurate identification and control to wire filling transverse position in wire filling GTAW process, improves welding efficiency and welding quality. BRIEF DESCRIPTION OF DRAWINGS

[0010] Figure 1 It is based on visual sensing's wire filling GTAW transverse wire filling position real-time control system schematic diagram.

[0011] Figure 2 Left is the schematic diagram of wire axis and arc axis, right is the image captured by visual sensor.

[0012] Figure 3 It is based on visual sensing's wire filling GTAW transverse wire filling position real-time control method flow chart. DETAILED DESCRIPTION

[0013] In order to better express the technical scheme and beneficial effects of the whole application, the present application will be further described in detail below in combination with drawings and implementation cases.The implementation mode of the present application is not limited to this.

[0014] Step one: wire axis and arc axis transverse distance calculation

[0015] In wire filling GTAW process, when the end of wire is located in the center of arc, the best welding effect can be obtained, and through experiment and data analysis, it can be measured that the maximum transverse deviation of wire is How to keep the transverse deviation of wire and arc in the range is a difficult problem, and the present application discloses a method for calculating the distance between the end of wire and the center of arc.As shown in Figure 1 When arc striking succeeds and welding starts, visual sensor on clamping device starts to run, real-time image information in welding process is captured and transmitted to image information processor to calculate the distance between the end of wire and the center of arc, after receiving image information, image information processor processes the picture to obtain the coordinates (x n , y n ) of each point of wire axis, and transmits the data to wire transverse position controller through communication bus.

[0016] Step two: wire filling GTAW transverse wire filling position real-time control

[0017] In the GTAW process of filling wire, the transverse wire filling position has an important influence on welding efficiency and weld quality, so the transverse wire filling position needs to be controlled during welding to obtain the best transverse wire filling position. In view of this problem, the present application discloses a kind of wire transverse automatic adjusting method, control wire transverse position to keep wire axis always intersects with arc axis. The wire transverse position controller receives the coordinates (x n , y n ) of each point of wire axis transmitted by image information processor;If x1-x2 <α, x1-x3 <α, x1-x4 <α,..., x1-x n <α, α is the maximum deviation value of wire axis abscissa;Take abscissa x=x1, when wire axis end point coincides with arc axis, wire axis intersects with arc axis;When , wire transverse position controller sends instruction to driver, to control high-precision adjusting slider to move wire feeding pipe to x=0 on x axis negative half axis;When , wire transverse position controller sends instruction to driver, to control high-precision adjusting slider to move wire feeding pipe to x=0 on x axis positive half axis;When , keep stable unchanged, to achieve the purpose of real-time control of transverse wire filling position.

Claims

1. A method for real-time control of the transverse wire position in GTAW with filler wire based on visual sensing, which is used to adjust the transverse position of the wire in GTAW in real time during the welding process, to ensure that the wire axis always intersects with the arc axis, and to improve the welding efficiency and quality, characterized in that: The visual-sensing-based filler wire GTAW transverse filler wire position real-time control method is realized by a visual-sensing-based filler wire GTAW transverse filler wire position real-time control system; the visual-sensing-based filler wire GTAW transverse filler wire position real-time control system is composed of a visual sensor, an image information processor, a filler wire transverse position controller, a filler wire transverse adjusting mechanism, a visual sensor position adjusting mechanism, a clamping device, a high-precision wire feeder, a wire feeding pipe and a welding torch; the visual sensor is used for real-time monitoring of the positions of the filler wire axis and the arc axis, real-time acquisition of welding process images by the visual sensor and transmission of the image information to the image information processor; the image information processor is used for processing of the image information from the visual sensor, calculation of the transverse distance between the filler wire axis and the arc axis by a filler wire axis and arc axis transverse distance calculation method and real-time transmission of the filler wire axis and arc axis transverse distance data to the filler wire transverse position controller through a communication bus; the filler wire transverse position controller is used for identification of the transverse positions of the filler wire axis and the arc axis and adjustment and control of the filler wire transverse position, so that the filler wire axis always intersects with the arc axis; the visual sensor position adjusting mechanism is used for automatic adjustment of the position of the visual sensor; the clamping device is used for fixation of the visual sensor and the wire feeding pipe on the welding torch; the high-precision wire feeder is used for accurate adjustment and control of the wire feeding speed; the wire feeding pipe is used for conveying of the filler wire; before starting welding, the visual sensor transmits the image information to the image information processor, detects whether the center line of the captured image coincides with the arc center line, and if not, adjusts the angle and height of the visual sensor through the angle adjusting shaft and the height adjusting slider to make the image center line coincide with the arc center line and ensure that the captured image contains the filler wire axis and the arc axis to realize real-time monitoring of the positions of the filler wire axis and the arc axis; the filler wire axis and arc axis transverse distance calculation method is used for real-time detection of the transverse position of the filler wire in the arc; the filler wire axis and arc axis transverse distance calculation method is a calculation method for obtaining accurate filler wire axis and arc axis transverse distance data by processing and calculation of the real-time image information captured by the visual sensor through the image information processor; the filler wire axis and arc axis transverse distance calculation method is a method for gray-scale processing of the received real-time welding process images by the image information processor and definition of the arc and filler wire area images, filtering processing of the area images by a Gaussian filtering method and obtaining of the filler wire axis point coordinates by a filler wire axis detection algorithm; the filler wire axis point coordinates are the point coordinates of the filler wire axis in the rectangular coordinate system established with the image center point as the origin; the filler wire axis detection algorithm is a method for sequentially obtaining the point coordinates of the two sides of the filler wire from the end of the filler wire upwards, keeping the vertical coordinates of the two points unchanged and taking the median value of the horizontal coordinates of the two points to obtain the horizontal coordinate of the point on the axis, so as to obtain the coordinates of each point on the filler wire axis (x n , y n ); the method of automatic adjustment of the transverse position of the welding wire ensures that the axis of the welding wire and the axis of the arc intersect by identifying and correcting the transverse position deviation of the welding wire; the transverse position controller of the welding wire receives the coordinates (x n , y n ) of each point of the axis of the welding wire transmitted by the image information processor; the transverse position controller of the welding wire determines whether the transverse coordinates of each point of the axis of the welding wire are the same; if x1-x2 <α, |x1-x3|<α, |x1-x4|<α,..., x1-x n |<α, α is the maximum deviation value of the transverse coordinates of the axis of the welding wire; taking the transverse coordinate x=x1 and the coordinates (x1, y1) of the end of the axis of the welding wire as the terminal coordinates, the axis of the welding wire intersects with the axis of the arc when the terminal point of the axis of the welding wire coincides with the axis of the arc; when , the transverse position controller of the welding wire sends a command to the driver to control the high-precision adjustment slider to move the wire feeding tube to x=0 along the negative half of the x-axis; when , the transverse position controller of the welding wire sends a command to the driver to control the high-precision adjustment slider to move the wire feeding tube to x=0 along the positive half of the x-axis; is the maximum value of the transverse deviation of the welding wire that can be ensured under the condition of good welding quality.

2. The real-time control method for the lateral filler position of GTAW based on vision sensing according to claim 1, characterized in that: Real-time images of the welding wire and the arc during the welding process are collected by a visual sensor; the visual sensor is fixed on the welding torch through a clamping device, the central axis of the visual sensor and the central axis of the wire feeding pipe are coplanar and are respectively distributed on both sides of the welding torch; the clamping device is composed of a visual sensor clamping arm and a wire feeding pipe clamping arm; the visual sensor is connected with an angle adjusting shaft and a height adjusting slider, and the slide rail of the height adjusting slider is connected with the welding torch through the visual sensor clamping arm.

3. The real-time control method for the lateral filler position of GTAW based on vision sensing according to claim 1, characterized in that: The welding wire transverse adjusting mechanism is composed of a high-precision adjusting slider and a driver, which is used to control the transverse position of the welding wire in real time; the bottom of the high-precision adjusting slider is fixed on the welding torch by the wire feeding pipe clamping arm, and the moving part of the high-precision adjusting slider is fixedly connected with the wire feeding pipe; the driver is connected with the welding wire transverse position controller through a communication bus to receive the displacement and speed parameters of the transverse movement of the welding wire, and drives the high-precision adjusting slider through a control line to control the transverse position of the welding wire in real time.

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