Filling wire GTAW transverse filling wire position real-time control method based on visual sensing

Abstract

The invention relates to a real-time control method for a transverse wire filling position of a wire filling GTAW based on visual sensing. A visual sensor is used for collecting images of welding arcs in the welding process in real time; detecting the transverse position of the welding wire in the electric arc in real time by using a method for calculating the transverse distance between the welding wire axis and the electric arc axis; the welding wire transverse adjusting mechanism is used for adjusting the transverse position of the welding wire in real time; and controlling the transverse position of the welding wire by utilizing a welding wire transverse automatic adjusting method to keep the axis of the welding wire intersected with the arc axis all the time. According to the method, the transverse position of the filling wire is accurately recognized and regulated successfully in the GTAW process of the filling wire, and the welding efficiency and quality are further improved.

Description

Technical Field

[0001] The invention relates to the field of visual sensing GTAW transverse wire filling position real-time control, and is a visual sensing-based GTAW transverse wire filling position real-time control method. Background Art

[0002] Wire-filled GTAW (gas shielded 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 been increasingly rapid, and higher and higher requirements have been put forward for the automation and intelligence of wire-filled GTAW. In the wire-filled GTAW process, the lateral deviation between the welding wire and the arc has an extremely significant impact on the welding efficiency and the quality of the weld. The intersection of the welding wire axis and the arc axis is conducive to maintaining the stability of the arc and forming high-quality welds. However, there is currently no method that can realize the real-time control of the lateral filling wire position of wire-filled GTAW. In response to this problem, the present invention discloses a real-time control method for the lateral filling wire position of wire-filled GTAW based on visual sensing. Summary of the invention

[0003] The real-time control method of the GTAW transverse wire position of the filler wire based on visual sensing is used for real-time feedback adjustment of the lateral position of the welding wire during the GTAW welding process, so as to ensure that the welding wire axis always intersects with the arc axis, and improve the welding efficiency and quality. The method is characterized in that: the real-time control method of the GTAW transverse wire position of the filler wire based on visual sensing is realized by using the real-time control system of the GTAW transverse wire position of the filler wire based on visual sensing. The system schematic diagram is shown in FIG. Figure 1 As shown; the real-time control system for the GTAW transverse wire position of the wire filling based on visual sensing 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 tube, and a welding gun; the visual sensor is used to monitor the position of the welding wire axis and the arc axis in real time, collect real-time images of the welding process 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 using the transverse distance calculation method between the welding wire axis and the arc axis, 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 the communication bus; the welding wire transverse position controller is used to identify the transverse position of the welding wire axis and the arc axis, and regulate the transverse position of the welding wire 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 tube on the welding gun; the high-precision wire feeder is used to accurately regulate the wire feeding speed; the wire feeding tube is used to transport the welding wire.

[0004] The real-time control method of the GTAW horizontal filling wire position based on visual sensing is characterized in that: a visual sensor is used to collect real-time images of the welding wire and the arc during welding; the visual sensor is fixed to the welding gun through a clamping device, and the central axis of the visual sensor is coplanar with the central axis of the wire feeding tube and is respectively distributed on both sides of the welding gun; the clamping device is composed of a visual sensor clamping arm and a wire feeding tube clamping arm; the visual sensor is connected to the height adjustment slider through an angle adjustment shaft, and the slide rail of the height adjustment slider is connected to the welding gun through the visual sensor clamping arm; before starting welding, the visual sensor transmits image information to the image information processor to detect whether the center line of the captured image coincides with the center line of the arc. If not, the angle and height of the visual sensor are adaptively adjusted through the angle adjustment shaft and the height adjustment slider to make the image center line coincide with the arc center line, and ensure that the welding wire axis and the arc axis are included in the image field to monitor the position of the welding wire axis and the arc axis in real time, such as Figure 2 Shown right.

[0005] The real-time control method of the GTAW lateral wire position of the filler wire based on visual sensing is characterized in that: the lateral position of the welding wire in the arc is detected in real time by using a method for calculating the lateral distance between the welding wire axis and the arc axis; the method for calculating the lateral distance between the welding wire axis and the arc axis is a method for calculating the accurate lateral distance data between the welding wire axis and the arc axis by processing and calculating the real-time image information captured by the visual sensor through an image information processor; the method for calculating the lateral distance between the welding wire axis and the arc axis is a method for calculating the real-time welding process image received by the image information processor. The image is grayed out, and the arc and welding wire area image is defined. The area image is filtered using the Gaussian filtering method, and finally the welding wire axis detection algorithm is used to obtain the coordinates of each point on the welding wire axis; the coordinates of each point on the welding wire axis are the coordinates of each point on the welding wire axis in a rectangular coordinate system established with the center point of the image as the origin; the welding wire axis detection algorithm first obtains the coordinates of each point on the edge of the welding wire on both sides from the end of the welding wire upward in sequence, and then keeps the ordinates of the two points with the same ordinate unchanged, takes the median of the two points for the abscissa, and obtains the abscissa of the point on the axis, and the coordinates (x n ,y n ).

[0006] The method for real-time control of the GTAW lateral wire position based on visual sensing is characterized in that: the lateral adjustment mechanism of the welding wire consists of a high-precision adjustment slider and a driver, which is 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 gun 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 real-time control method of the lateral filling wire position of the filling wire GTAW based on visual sensing is as follows: Figure 3 As shown, it is characterized in that: the automatic lateral adjustment method of the welding wire ensures that the welding wire axis and the arc axis always intersect by identifying and correcting the lateral position deviation of the welding wire; the lateral position controller of the welding wire receives the coordinates (x n ,y n ); the welding wire transverse position controller determines whether the horizontal coordinates of each point on the welding wire axis are the same; if |x 1 -x 2 |<α,|x 1 -x 3 |<α,|x 1 -x 4 |<α,...,|x 1 -x n |<α, α is the maximum deviation of the horizontal coordinate of the welding wire axis; take the horizontal coordinate x=x 1 According to claim 3, (x 1 ,y 1 ) is the coordinate of the end point of the welding wire axis, and the welding wire axis intersects with the arc axis when the end point of the welding wire axis coincides with the arc axis; when x>ξ, the welding wire lateral position controller sends a command to the driver to control the high-precision adjustment slider to move the wire feeding tube to the negative half axis of the x-axis to x=0; when x<-ξ, the welding wire lateral position controller sends a command to the driver to control the high-precision adjustment slider to move the wire feeding tube to the positive half axis of the x-axis to x=0; ξ is the maximum value of the lateral deviation of the welding wire measured in the experiment while ensuring good welding quality.

[0008] Advantageous Effects of the Invention

[0009] The present invention relates to a real-time control method for the transverse position of a GTAW wire-filler based on visual sensing. A visual sensor is used to collect real-time images of the welding wire and the arc during welding; a method for calculating the transverse distance between the welding wire axis and the arc axis is used to detect the transverse position of the welding wire in the arc in real time; a welding wire transverse adjustment mechanism is used to adjust the transverse position of the welding wire in real time; and a welding wire transverse automatic adjustment method is used to control the transverse position of the welding wire to keep the welding wire axis always intersecting with the arc axis. The present invention successfully realizes the precise identification and regulation of the transverse position of the filler wire during the GTAW process, thereby improving welding efficiency and welding quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is the schematic diagram of the real-time control system for the lateral filling wire position of GTAW with filling wire based on visual sensing.

[0011] Figure 2 On the left is a schematic diagram of the welding wire axis and the arc axis, and on the right is the image captured by the visual sensor.

[0012] Figure 3 This is a flow chart of the real-time control method of the lateral filling wire position in GTAW with filling wire based on visual sensing. DETAILED DESCRIPTION

[0013] In order to better express the technical solution and beneficial effects of the entire invention, the present invention is further described in detail below with reference to the accompanying drawings and implementation examples. The implementation methods of the present invention are not limited thereto.

[0014] Step 1: Calculation of the horizontal distance between the welding wire axis and the arc axis

[0015] In the wire-filled GTAW process, the best welding effect can be obtained when the end of the welding wire is located at the center of the arc. Through experiments and data analysis, it can be measured that the maximum lateral deviation of the welding wire is ξ while ensuring good welding quality. How to keep the lateral deviation between the welding wire and the arc within the range ξ is a difficult problem. To address this problem, the present invention discloses a method for calculating the distance between the end of the welding wire and the center of the arc. Figure 1 As shown in the figure, when the arc is successfully struck and welding begins, the visual sensor on the clamping device starts to operate, capturing the image information of the welding process in real time and transmitting it to the image information processor to calculate the distance between the end of the welding wire and the center of the arc. After receiving the image information, the image information processor processes the image to obtain the coordinates of each point on the welding wire axis (x n ,y n ), and transmit the data to the wire lateral position controller via the communication bus.

[0016] Step 2: Real-time control of GTAW horizontal wire filling position

[0017] In the wire-filled GTAW process, the transverse wire position has an important influence on the welding efficiency and the weld quality. Therefore, it is necessary to control the transverse wire position during welding to obtain the optimal transverse wire position. To address this problem, the present invention discloses a method for automatically adjusting the transverse position of the welding wire to control the transverse position of the welding wire so as to keep the welding wire axis always intersecting with the arc axis. The welding wire transverse position controller receives the coordinates (x n ,y n ); if |x 1 -x 2 |<α,|x 1 -x 3 |<α,|x 1 -x 4 |<α,...,|x 1 -x n |<α, α is the maximum deviation of the horizontal coordinate of the welding wire axis; take the horizontal coordinate x=x 1 , when the end point of the welding wire axis coincides with the arc axis, the welding wire axis intersects with the arc axis; when x>ξ, the welding wire lateral position controller sends a command to the driver to control the high-precision adjustment slider to move the wire feeding tube to the negative half axis of the x-axis to x=0; when x<-ξ, the welding wire lateral position controller sends a command to the driver to control the high-precision adjustment slider to move the wire feeding tube to the positive half axis of the x-axis to x=0; when -ξ≤x≤ξ, it remains stable, so as to achieve the purpose of real-time control of the lateral filling wire position.

Claims

1. A real-time control method for the lateral position of the wire in GTAW with filler wire based on visual sensing is used for real-time feedback adjustment of the lateral position of the wire in the GTAW welding process to ensure that the wire axis always intersects with the arc axis, thereby improving welding efficiency and quality. The method is characterized by: The method for real-time control of the GTAW transverse wire position of the filler wire based on visual sensing is realized by using the real-time control system of the GTAW transverse wire position of the filler wire based on visual sensing; the real-time control system of the GTAW transverse wire position of the filler wire based on visual sensing 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 tube, and a welding gun; the visual sensor is used to monitor the position of the welding wire axis and the arc axis in real time, and the visual sensor is used to collect the welding process image in real time, and the image information is transmitted to the image information processor; the image information processor is used to process the image information. The lateral distance between the welding wire axis and the arc axis is calculated based on the image information of the visual sensor using the lateral distance calculation method between the welding wire axis and the arc axis, and the lateral distance data between the welding wire axis and the arc axis is transmitted in real time to the welding wire lateral position controller through the communication bus; the welding wire lateral position controller is used to identify the lateral position of the welding wire axis and the arc axis, and to adjust the lateral position of the welding wire 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 tube on the welding gun; the high-precision wire feeder is used to accurately adjust the wire feeding speed; the wire feeding tube is used to transport the welding wire.

2. The real-time control method of the lateral wire position of the GTAW wire filling machine based on visual sensing according to claim 1 is characterized by: A visual sensor is used to collect real-time images of the welding wire and the arc during the welding process; the visual sensor is fixed to the welding gun through a clamping device, and the central axis of the visual sensor is coplanar with the central axis of the wire feeding tube and is respectively distributed on both sides of the welding gun; the clamping device is composed of a visual sensor clamping arm and a wire feeding tube clamping arm; the visual sensor is connected to a height adjustment slider through an angle adjustment shaft, and the slide rail of the height adjustment slider is connected to the welding gun through the visual sensor clamping arm; before starting welding, the visual sensor transmits image information to an image information processor to detect whether the center line of the captured image coincides with the center line of the arc. If not, the angle and height of the visual sensor are adaptively adjusted through the angle adjustment shaft and the height adjustment slider to make the image center line coincide with the arc center line, and ensure that the captured image contains the welding wire axis and the arc axis to monitor the positions of the welding wire axis and the arc axis in real time.

3. The real-time control method of the lateral wire position of the GTAW wire filling machine based on visual sensing according to claim 1 is characterized by: The lateral position of the welding wire in the arc is detected in real time by using a method for calculating the lateral distance between the welding wire axis and the arc axis. The method for calculating the lateral distance between the welding wire axis and the arc axis is a method for calculating the accurate lateral distance data between the welding wire axis and the arc axis by processing and calculating the real-time image information captured by the visual sensor through an image information processor. The method for calculating the lateral distance between the welding wire axis and the arc axis is to grayscale the received real-time welding process image using an image information processor, define the arc and welding wire area image, filter the area image using a Gaussian filter method, and finally use a welding wire axis detection algorithm to obtain the coordinates of each point on the welding wire axis. The coordinates of each point on the welding wire axis are the coordinates of each point on the welding wire axis in a rectangular coordinate system established with the center point of the image as the origin. The welding wire axis detection algorithm is to first obtain the coordinates of each point on the edge of the welding wire from the end of the welding wire upward in sequence, and then keep the ordinates of the two points with the same ordinate unchanged, take the median of the two points for the abscissa, and obtain the abscissa of the point on the axis, so as to obtain the coordinates of each point on the welding wire axis (x n ,y n ).

4. The real-time control method of the lateral wire position of the GTAW wire filling machine based on visual sensing according to claim 1 is characterized by: The welding wire lateral adjustment mechanism is composed of a high-precision adjustment slider and a driver, which is 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 gun 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 welding wire lateral position controller 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.

5. The method for real-time control of the lateral wire position of GTAW wire filling based on visual sensing according to claim 1 is characterized in that: The method for automatically adjusting the lateral position of the welding wire ensures that the welding wire axis and the arc axis always intersect by identifying and correcting the lateral position deviation of the welding wire; the welding wire lateral position controller receives the coordinates (x n ,y n ); the welding wire transverse position controller determines whether the horizontal coordinates 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, α is the maximum deviation value of the horizontal coordinate of the welding wire axis; take the horizontal coordinate x=x1, according to Claim 3, it can be known that (x1, y1) is the end coordinate of the welding wire axis, and the welding wire axis intersects with the arc axis when the end point of the welding wire axis coincides with the arc axis; when x>ξ, the welding wire lateral position controller sends an instruction to the driver to control the high-precision adjustment slider to move the wire feeding tube to the negative half axis of the x-axis to x=0; when x<-ξ, the welding wire lateral position controller sends an instruction to the driver to control the high-precision adjustment slider to move the wire feeding tube to the positive half axis of the x-axis to x=0; ξ is the maximum value of the lateral deviation of the welding wire measured in the experiment while ensuring good welding quality.

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