Online control method for relative position between wire and electron beam in electron beam fuse deposition

Abstract

The present invention provides an online control method for the relative position of a wire and an electron beam during electron beam fuse deposition. The method comprises: obtaining the real-time relative position of the wire and the electron beam; determining the deviation between the real-time relative position of the wire and the electron beam and the target relative position based on a pre-calibrated target relative position of the wire and the electron beam; determining a control parameter for the wire based on the deviation; and adjusting the real-time relative position of the wire and the electron beam online based on the control parameter. By monitoring and adjusting the relative position of the wire and the electron beam in real time during electron beam fuse deposition, this method ensures that the relative position of the wire and the electron beam does not deviate from the ideal value, thereby effectively improving the stability and continuity of the manufacturing process.

Description

Technical Field

[0001] The present invention relates to the technical field of online control of additive manufacturing, and in particular to an online control method for the relative position of a wire and an electron beam in electron beam fuse deposition. Background Art

[0002] Electron beam fuse deposition (EBFD) is a highly efficient, high-quality, and large-scale metal part manufacturing method with promising applications in aerospace, automotive, and medical fields. The stability and continuity of the manufacturing process are crucial for ensuring EBFD quality. Proper melting of the wire and accurate transition to the molten pool are particularly important.

[0003] During the actual fuse deposition process, deformation caused by the large stress inside the wire, thermal deformation caused by the high temperature gradient when the wire melts, and other random factors may cause the end of the wire to instantly deviate from the electron beam range, which not only affects the stability of the droplet transfer, but also may affect the normal melting of the wire, and even cause phenomena such as wire sticking and wire failure to melt, thereby causing deposition interruption.

[0004] Therefore, it is necessary to adopt an online control method to monitor and adjust the relative position of the wire and the electron beam in real time during the electron beam fuse deposition process to ensure that the relative position of the wire and the electron beam does not deviate from the ideal value, thereby improving the stability and continuity of the manufacturing process. Summary of the Invention

[0005] The present invention provides an online control method for the relative position of a wire and an electron beam in electron beam fuse deposition, which is used to overcome the defect that the existing electron beam fuse deposition method cannot ensure the stability and continuity of the manufacturing process. The online control method is used to monitor and adjust the relative position of the wire and the electron beam in real time during the electron beam fuse deposition process, ensuring that the relative position of the wire and the electron beam does not deviate from the ideal value, thereby improving the stability and continuity of the manufacturing process.

[0006] On the one hand, the present invention provides an online control method for the relative position of a wire and an electron beam in electron beam fuse deposition, comprising: obtaining the real-time relative position of the wire and the electron beam; determining the deviation between the real-time relative position of the wire and the electron beam and the target relative position based on a pre-calibrated target relative position of the wire and the electron beam; determining the control parameters of the wire based on the deviation; and adjusting the real-time relative position of the wire and the electron beam online based on the control parameters of the wire.

[0007] Furthermore, the target relative position of the wire and the electron beam is pre-calibrated, specifically including: acquiring an initial image of the relative position of the wire and the electron beam; extracting the melting mark area and the wire area in the initial image using an image recognition algorithm; calculating the centroid coordinates of the melting mark area and the wire axis equation corresponding to the wire axis in the wire area; determining the target relative position of the wire and the electron beam based on the centroid coordinates and the wire axis equation; wherein the centroid coordinates in the target relative position are a point on the wire axis equation, the actual physical size corresponding to a single pixel in the initial image is lower than a preset threshold, and the acquisition interval of the initial image is lower than the time required for the real-time relative position of the wire and the electron beam to change by a preset threshold.

[0008] Furthermore, the extraction of the melting mark area and the wire area in the initial image using an image recognition algorithm includes: performing threshold segmentation processing on the enhanced initial image to obtain the melting mark area; compensating for the low grayscale value area inside the melting mark area that is blocked by the wire to obtain the compensated melting mark area; and performing difference processing between the compensated melting mark area and the melting mark area to obtain the wire area.

[0009] Furthermore, determining the deviation between the real-time relative position of the wire and the electron beam and the target relative position includes: determining that any point on the real-time wire axis equation does not belong to the discrimination area, then making a perpendicular line to the wire axis equation through the centroid coordinates in the target relative position; determining the intersection of the perpendicular line and the real-time wire axis equation; wherein the discrimination area is a circular area with the centroid coordinates in the target relative position as the center and the electron beam radius as the radius, and the deviation is the distance between the centroid coordinates and the intersection.

[0010] Furthermore, determining the deviation between the real-time relative position of the wire and the electron beam and the target relative position includes: determining that there is at least one point on the real-time wire axis equation that belongs to a discrimination area, and then identifying the point with the largest grayscale gradient value in the direction of the real-time wire axis; wherein the discrimination area is a circular area with the centroid coordinates in the target relative position as the center and the electron beam radius as the radius, the deviation is the distance from the point with the largest grayscale gradient value to the wire axis in the target relative position, and the grayscale gradient value is calculated as follows:

[0011]

[0012] Where i is the pixel number on the real-time wire axis, x and y are the horizontal and vertical coordinates of the pixel on the real-time wire axis, S is the real-time wire axis, and I is the grayscale value of the pixel.

[0013] Furthermore, determining the control parameter of the wire according to the deviation includes: determining a deviation interval in which the deviation is located; and determining the control parameter of the wire according to the deviation and the deviation interval.

[0014] Furthermore, determining the deviation interval in which the deviation is located specifically includes: determining that any point on the real-time wire axis equation does not belong to the discrimination area, then the deviation belongs to the first deviation interval; determining that at least one point on the real-time wire axis equation belongs to the discrimination area, and the value of the deviation is greater than a set threshold, then the deviation belongs to the second deviation interval; determining that at least one point on the real-time wire axis equation belongs to the discrimination area, and the value of the deviation is less than or equal to the set threshold, then the deviation belongs to the third deviation interval.

[0015] Furthermore, determining the control parameters of the wire according to the deviation amount and the deviation interval includes: determining that the deviation amount is in the first deviation interval or the second deviation interval; determining the moving direction, moving speed and moving distance of the wire according to the numerical value and sign of the deviation amount; or, determining that the deviation amount is in the third deviation interval, not adjusting the real-time relative position of the wire and the electron beam.

[0016] In a second aspect, the present invention also provides an online control device for the relative position of the wire and the electron beam in electron beam fuse deposition, comprising: a real-time relative position acquisition module for acquiring the real-time relative position of the wire and the electron beam; a position deviation determination module for determining the deviation between the real-time relative position of the wire and the electron beam and the target relative position based on a pre-calibrated target relative position of the wire and the electron beam; a control parameter determination module for determining the control parameters of the wire based on the deviation; and an online control adjustment module for adjusting the real-time relative position of the wire and the electron beam online based on the control parameters of the wire.

[0017] In a third aspect, the present invention also provides an electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, an online control method for the relative position of the wire and the electron beam in electron beam fuse deposition as described in any one of the above is implemented.

[0018] The present invention provides an online control method for the relative position of a wire and an electron beam during electron beam fuse deposition. The method obtains the real-time relative position of the wire and the electron beam, determines the deviation between the real-time relative position of the wire and the electron beam and the target relative position based on a pre-calibrated target relative position of the wire and the electron beam, and determines a control parameter for the wire based on the deviation. The real-time relative position of the wire and the electron beam is then adjusted online based on the control parameter. This method ensures that the relative position of the wire and the electron beam does not deviate from the ideal value during electron beam fuse deposition, thereby effectively improving the stability and continuity of the manufacturing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 A schematic diagram of an electron beam fuse deposition additive manufacturing device provided by the present invention;

[0021] Figure 2 A schematic flow chart of an online control method for the relative position of a wire and an electron beam in electron beam fuse deposition provided by the present invention is shown;

[0022] Figure 3 A schematic diagram of pre-calibration of the online control method for the relative position of the wire and the electron beam in the electron beam fuse deposition process provided by the present invention;

[0023] Figure 4 A schematic diagram of wire position deviation in the method for online control of the relative position of the wire and the electron beam in the electron beam fuse deposition process provided by the present invention;

[0024] Figure 5 This is a schematic diagram of the overall process of the online control method for the relative position of the wire and the electron beam in electron beam fuse deposition provided by the present invention;

[0025] Figure 6 A schematic structural diagram of an online control device for the relative position of a wire and an electron beam in electron beam fuse deposition provided by the present invention;

[0026] Figure 7 This is a schematic structural diagram of the electronic device provided by the present invention.

[0027] Reference numerals:

[0028] 1: Electron beam fused deposition additive manufacturing equipment; 2: Industrial camera; 3: Industrial computer; 4: Wire feeding mechanism; 5: Wire; 6: Electron beam; 7: Substrate; 8: Melt mark area; 9: Centroid; 10: Wire axis; 11: Target relative position; 12: Identification area; 13: Real-time wire axis; 14: Real-time relative position; 15: Intersection of the perpendicular line of the wire axis drawn through the centroid of the target relative position and the real-time wire axis; 16: The point with the maximum grayscale gradient value along the real-time wire axis. DETAILED DESCRIPTION

[0029] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0030] It should be noted that before the fuse deposition process begins, the hardware of the electron beam fuse deposition additive manufacturing equipment used in the fuse deposition process needs to be installed and connected. The electron beam fuse deposition additive manufacturing equipment here is also the online control system that is applicable throughout the subsequent fuse deposition process.

[0031] Specifically, Figure 1 The schematic diagram of the electron beam fused deposition additive manufacturing device provided by the present invention is shown. Figure 1 As shown, the electron beam fused deposition additive manufacturing device 1 includes hardware devices such as an industrial camera 2, an industrial computer 3, a wire feeding mechanism 4 and a substrate 7 required to complete online control, and establishes connections between various hardware devices to achieve online control.

[0032] Adjust the installation position of the industrial camera 2 in the electron beam fuse deposition additive manufacturing equipment 1 so that an image of the relative position of the wire 5 and the electron beam 6 can be obtained from a top-down perspective. Then, fix the position and field of view of the industrial camera 2 to ensure that the relative position relationship between the industrial camera 2 and the electron gun of the electron beam fuse deposition additive manufacturing equipment 1 remains unchanged during the forming process, and the field of view of the industrial camera 2 remains unchanged, thereby completing the hardware construction required for the online control method of the relative position of the wire and the electron beam.

[0033] During the fuse deposition process, the industrial camera 2 transmits the collected image of the relative position of the wire 5 and the electron beam 6 to the industrial computer 3, so that the industrial computer 3 generates a relative position control signal and controls the wire feeding mechanism 4 according to the relative position control signal to adjust the position of the wire 5 online in real time, thereby realizing online control of the real-time relative position of the wire 5 and the electron beam 6.

[0034] After completing the installation and connection of the hardware devices in the electron beam fuse deposition additive manufacturing device 1 , the online control method for the relative position of the wire and the electron beam in electron beam fuse deposition provided by the present invention is started.

[0035] Specifically, Figure 2 The figure shows a flow chart of the method for online controlling the relative position of the wire and the electron beam in electron beam fuse deposition provided by the present invention. Figure 1 As shown, the method includes:

[0036] S210, obtaining the real-time relative position of the wire and the electron beam.

[0037] It is understandable that in order to perform online control of the relative position of the wire and the electron beam in electron beam fuse deposition, it is first necessary to clarify the current state of the relative position of the wire and the electron beam, and whether the current state of the relative position of the wire and the electron beam needs to be adjusted.

[0038] By obtaining the real-time relative position of the wire and the electron beam, the current relative position status of the wire and the electron beam can be understood. Specifically, first, an industrial camera installed in the electron beam fuse deposition additive manufacturing equipment can be used to obtain an image corresponding to the real-time relative position of the wire and the electron beam. Then, an image recognition algorithm can be used to extract the real-time melt mark area and the real-time wire area in the above image. Based on the real-time melt mark area and the real-time wire area, the centroid coordinates of the real-time melt mark area and the real-time wire axis equation corresponding to the wire axis in the real-time wire area are calculated.

[0039] The wire axis position corresponding to the calculated real-time wire axis equation and the centroid position of the real-time melting mark area constitute the real-time relative position of the wire and the electron beam.

[0040] S220 , determining a deviation between the real-time relative position of the wire and the electron beam and the target relative position based on a pre-calibrated target relative position of the wire and the electron beam.

[0041] It can be understood that, based on the real-time relative position of the wire and the electron beam obtained in the above step S210, further, combined with the pre-calibrated target relative position of the wire and the electron beam, the deviation between the real-time relative position of the wire and the electron beam and the target relative position is calculated, so as to determine how to control and adjust the real-time relative position of the wire and the electron beam.

[0042] Among them, for the pre-calibrated target relative position of the wire and the electron beam, under the scenario of the target relative position, the end of the wire is preferably within the range of the electron beam, which can better achieve normal melting of the wire.

[0043] It should be noted that, in the pre-calibrated target relative position of the wire and the electron beam, the centroid of the melting mark area formed by the electron beam acting on the substrate is exactly a point on the wire axis equation corresponding to the wire.

[0044] It should also be noted that the step of pre-calibrating the target relative position of the wire and the electron beam is performed after installing and connecting the relevant hardware equipment of the electron beam fuse deposition additive manufacturing equipment, and before executing the online control method for the relative position of the wire and the electron beam in electron beam fuse deposition provided by the embodiment of the present invention.

[0045] Determine the deviation between the real-time relative position of the wire and the electron beam and the target relative position. In a specific embodiment, the deviation is calculated based on the distance between the position of the electron beam center in the target relative position and the position of a specific point on the wire axis in the real-time relative position.

[0046] The specific point may be a point with the largest grayscale gradient value in the direction of the wire axis in the real-time relative position, or an intersection of a perpendicular line to the wire axis in the target relative position through the centroid position in the target relative position and the real-time wire axis, which is not specifically limited here.

[0047] S230: Determine the control parameters of the wire according to the deviation.

[0048] Based on the deviation between the real-time relative position of the wire and the electron beam and the target relative position determined in the above step S220 , a control parameter of the wire is further determined according to the deviation.

[0049] It can be understood that the real-time relative position of the wire and the electron beam is monitored in real time based on the pre-calibrated target relative position of the wire and the electron beam. The deviation between the real-time relative position and the target relative position can be large or small. If it is large, the real-time relative position of the wire and the electron beam is adjusted. If it is small, there is no need to adjust the real-time relative position of the wire and the electron beam, and the current real-time relative position of the wire and the electron beam can be maintained.

[0050] The control parameters of the wire are determined based on the deviation. Specifically, the control parameters of the wire are determined based on the size and sign of the deviation. The control parameters of the wire include but are not limited to the moving distance, moving direction and moving speed of the wire. The sign of the deviation is used to determine the moving direction of the wire.

[0051] In a specific embodiment, a plurality of deviation ranges corresponding to the deviation amounts are pre-stored, and according to the determined deviation amount, the deviation range corresponding to the deviation amount is matched, and the control parameters of the wire are determined according to the deviation amount and the matched deviation range.

[0052] S240 , adjusting the real-time relative position of the wire and the electron beam online according to the control parameters of the wire.

[0053] Based on the control parameters of the wire determined according to the deviation amount in the above step S230, the wire feeding mechanism is controlled to control and adjust the real-time position of the wire according to the control parameters of the wire, so as to adjust the real-time relative position of the wire and the electron beam to the ideal value, thereby realizing online adjustment of the real-time relative position of the wire and the electron beam.

[0054] In this embodiment, the real-time relative position of the wire and electron beam is acquired, and the deviation between the real-time relative position of the wire and electron beam and the target relative position is determined based on a pre-calibrated target relative position of the wire and electron beam. Based on the deviation, the control parameters of the wire are determined, and the real-time relative position of the wire and electron beam is adjusted online based on the control parameters of the wire. This method ensures that the relative position of the wire and electron beam does not deviate from the ideal value by monitoring and adjusting the relative position of the wire and electron beam in real time during the electron beam fuse deposition process, thereby effectively improving the stability and continuity of the manufacturing process.

[0055] On the basis of the above embodiment, the target relative position of the wire and the electron beam is further pre-calibrated, specifically including: obtaining an initial image of the relative position of the wire and the electron beam; extracting the melting mark area and the wire area in the initial image using an image recognition algorithm; calculating the centroid coordinates of the melting mark area and the wire axis equation corresponding to the wire axis in the wire area; determining the target relative position of the wire and the electron beam based on the centroid coordinates and the wire axis equation; wherein the centroid coordinates in the target relative position are a point on the wire axis equation.

[0056] It is understandable that after installing and connecting the relevant hardware equipment of the electron beam fuse deposition additive manufacturing equipment, before executing the online control method of the relative position of the wire and the electron beam in the electron beam fuse deposition provided by the embodiment of the present invention, it is necessary to pre-calibrate the target relative position of the wire and the electron beam.

[0057] Specifically, the electron beam is first controlled to act solely on the substrate at the energy parameters intended for the fuse deposition process, forming a melt mark. The area corresponding to the melt mark is the melt mark region. An industrial camera then captures an initial image of the relative position of the wire and electron beam. This initial image is transmitted to an industrial computer, which uses an image recognition algorithm to extract the melt mark region and wire region from this initial image. The computer then calculates the centroid coordinates of the melt mark region and the wire axis equation corresponding to the wire axis in the wire region. Finally, based on the centroid coordinates and the wire axis equation, the target relative position of the wire and electron beam is determined.

[0058] It's important to note that within the initial image captured by the industrial camera of the relative position of the wire and electron beam, the wire should be unbent, meaning its axis should be a straight line. The centroid coordinates of the melt mark region are the projection of the electron beam axis onto the substrate plane.

[0059] The electron beam position forming the melt mark area on the substrate should be the position of the main electron beam that participates in the fuse and forms the electron beam during the forming process. The sub-electron beams for other purposes that appear during the forming process are not within the pre-calibrated range.

[0060] It should also be noted that in order to ensure the accuracy of monitoring and control, the actual physical size corresponding to a single pixel in the initial image should be lower than the preset threshold, and the acquisition interval of the initial image should be lower than the time required for the real-time relative position of the wire and the electron beam to change by a preset threshold. The preset threshold can be set according to actual conditions. In a specific embodiment, the preset threshold here is consistent with the subsequent set threshold.

[0061] An image recognition algorithm is used to extract the melting mark area and wire area in the initial image. Specifically, first, the initial image captured by the industrial camera is enhanced, and then the enhanced initial image is threshold segmented. The area with a grayscale value greater than a preset grayscale threshold is taken as the melting mark area, and the low grayscale value area inside the melting mark area that is blocked by the wire is compensated to obtain the compensated melting mark area. Then, the compensated melting mark area is subtracted from the melting mark area to obtain the wire area.

[0062] The preset grayscale threshold is determined according to parameters related to each electron beam and successive exposure parameters.

[0063] Calculate the centroid coordinates of the melt mark area and the wire axis equation corresponding to the wire axis in the wire area. Specifically, the melt mark area is obtained by the action of an electron beam on a substrate plate. Generally, the electron beam can be considered to be a cylinder in space. Therefore, the obtained melt mark area is circular, and the centroid of the melt mark area is the center of the circular area.

[0064] Calculate the wire axis equation corresponding to the wire axis in the wire area. Specifically, based on the wire area, solve the circumscribed rectangle of the wire area, determine the midpoints of the two short sides of the circumscribed rectangle, and the straight line formed by connecting these two midpoints is the wire axis. The wire axis equation can be determined based on the coordinates corresponding to these two midpoints.

[0065] After calculating the centroid coordinates of the melt mark region and the wire axis equation corresponding to the wire axis in the wire region, the target relative position of the wire and the electron beam is determined based on the centroid coordinates and the wire axis equation. Specifically, the wire feed mechanism of the electron beam fuse deposition apparatus is used to adjust the wire position until the centroid of the melt mark region coincides with a point on the wire axis equation corresponding to the wire axis. At this point, the centroid position and the wire axis position constitute the target relative position.

[0066] It should be noted that in the process of pre-calibrating the target relative position of the wire and the electron beam, the relevant parameters obtained include the centroid coordinates of the melting mark area in the image coordinate system, the wire axis equation at the target relative position, and the positive and negative signs of the deviation of the wire axis from the target relative position in the image coordinate system in a clockwise or counterclockwise direction. The deviation sign is used to determine the moving direction of the wire feeding mechanism, that is, the moving direction of the wire, during online control adjustment.

[0067] Figure 3 A schematic diagram illustrating pre-calibration of an online control method for the relative position of a wire and an electron beam in an electron beam fuse deposition process provided by the present invention is shown.

[0068] like Figure 3 As shown, before the fuse deposition process begins, it is first confirmed that the wire 5 within the image range obtained by the industrial camera 2 is not bent, that is, the wire axis 10 is a straight line. Then, the electron beam 6 acts on the substrate 7 separately with the various electron beam-related parameters to be used in the deposition process to form a melting mark area 8; the outline of the melting mark area 8 and the outline of the wire 5 in the image are extracted by the image processing algorithm, and the coordinates of the centroid 9 in the melting mark area 8 and the wire axis equation are calculated; the position of the wire 5 is adjusted by the wire feeding mechanism 4 until the coordinates of the centroid of the melting mark area 8 are exactly a point on the wire axis equation. At this time, the coordinates of the centroid 9 and the axis position of the wire axis equation constitute the target relative position 11.

[0069] In this embodiment, an initial image of the relative position of the wire 5 and the electron beam 6 is obtained, and an image recognition algorithm is used to extract the melting mark area 8 and the wire area in the initial image, and the coordinates of the centroid 9 in the melting mark area 8 and the wire axis equation corresponding to the wire axis in the wire area are calculated. Therefore, according to the coordinates of the centroid 9 and the wire axis equation, the target relative position 11 of the wire 5 and the electron beam 6 is determined to determine the deviation between the target relative position 11 and the real-time relative position, and according to the deviation, the control parameters of the wire 5 are determined, and the real-time relative position of the wire 5 and the electron beam 6 is adjusted online to ensure that the relative position of the wire 5 and the electron beam 6 does not deviate from the ideal value, thereby effectively improving the stability and continuity of the manufacturing process.

[0070] On the basis of the above embodiment, further, the deviation between the real-time relative position of the wire and the electron beam and the target relative position is determined, including: determining that any point on the real-time wire axis equation does not belong to the judgment area, then drawing a perpendicular line to the wire axis equation through the centroid coordinates in the target relative position; determining the intersection of the perpendicular line and the real-time wire axis equation; wherein the judgment area is a circular area with the centroid coordinates in the target relative position as the center and the electron beam radius as the radius, and the deviation is the distance between the centroid coordinates and the intersection.

[0071] It can be understood that, in determining the deviation between the real-time relative position of the wire and the electron beam and the target relative position, specifically, this embodiment adopts a segmented definition for the deviation.

[0072] In the image, a circular area formed by the centroid coordinates of the target relative position and the electron beam spot radius in the substrate plane is used as the judgment area. The first segmentation condition is whether there is a point on the real-time wire axis equation that falls within the judgment area.

[0073] In a specific embodiment, when any point on the real-time wire axis equation does not belong to the discrimination area, a perpendicular line to the wire axis equation in the target relative position is drawn through the centroid coordinates in the target relative position. At this time, there will be an intersection between the perpendicular line and the real-time wire axis equation. The distance between the intersection and the centroid coordinates is the deviation between the real-time relative position of the wire and the electron beam and the target relative position.

[0074] In another specific embodiment, when there is at least one point on the real-time wire axis equation that belongs to the discrimination area, the pixel point with the largest grayscale gradient value in the real-time wire axis direction is identified, and the distance between the pixel point and the wire axis in the target relative position is the deviation between the real-time relative position of the wire and the electron beam and the target relative position.

[0075] Figure 4 A schematic diagram of wire position deviation in an online control method for the relative position of a wire and an electron beam in an electron beam fuse deposition process provided by the present invention is shown.

[0076] like Figure 4 As shown in the left figure, when any point on the real-time wire axis equation does not belong to the discrimination area 12, a perpendicular line is drawn through the centroid 9 to the wire axis equation corresponding to the wire axis 10 in the target relative position 11. The perpendicular line intersects the real-time wire axis 13 at an intersection 15. At this time, the centroid 9 and the real-time wire axis 13 form a real-time relative position 14, and the deviation is the length d of the perpendicular line between the centroid 9 and the intersection 15.

[0077] like Figure 4As shown in the right figure, when there is a point on the real-time wire axis equation that falls within the above-mentioned judgment area 12, the point 16 with the largest grayscale gradient along the real-time wire axis 13 is identified. At this time, the deviation amount is the distance d between the point 15 with the largest grayscale gradient and the wire axis 10 in the target relative position.

[0078] The calculation formula for the grayscale gradient value of pixel i in the wire axis direction is as follows:

[0079]

[0080] Where i is the pixel number on the real-time wire axis, x and y are the horizontal and vertical coordinates of the pixel on the real-time wire axis, S is the real-time wire axis, and I is the grayscale value of the pixel.

[0081] In this embodiment, by determining whether there is at least one point on the real-time wire axis that belongs to the discrimination area, the deviation between the real-time relative position of the wire and the electron beam and the target relative position is defined differently according to different determination results, so as to determine the control parameters of the wire according to the deviation, and adjust the real-time relative position of the wire and the electron beam online to ensure that the relative position of the wire and the electron beam does not deviate from the ideal value, thereby effectively improving the stability and continuity of the manufacturing process.

[0082] Based on the above embodiment, further determining the control parameters of the wire according to the deviation includes: determining a deviation interval in which the deviation is located; and determining the control parameters of the wire according to the deviation and the deviation interval.

[0083] It can be understood that the control parameters of the wire are determined based on the deviation between the real-time relative position of the wire and the electron beam and the target relative position. Specifically, the corresponding deviation interval can be determined based on the deviation, and thus the control parameters of the wire are determined based on the deviation and the deviation interval to which it belongs.

[0084] The deviation interval in which the deviation is located can be determined based on the discrimination area and the set threshold. Specifically, if any point on the real-time wire axis equation does not belong to the discrimination area, it can be determined that the deviation belongs to the first deviation interval, i.e., the large deviation interval; if at least one point on the real-time wire axis equation belongs to the discrimination area and the deviation value is greater than the set threshold, then the deviation belongs to the second deviation interval, i.e., the small deviation interval; if at least one point on the real-time wire axis equation belongs to the discrimination area and the deviation value is less than or equal to the set threshold, then the deviation belongs to the third deviation interval, i.e., the expected interval.

[0085] Among them, the deviation amount of the wire decreases in the first deviation interval, the second deviation interval and the third deviation interval. The threshold is set based on parameters such as part forming accuracy, wire diameter, electron beam spot size and molten pool size, and is determined comprehensively through experiments in combination with the hardware and algorithm performance of the online control system.

[0086] The control parameters of the wire are determined based on the deviation amount and the deviation interval to which it belongs. Specifically, in a specific embodiment, it is determined that the deviation amount is in the first deviation interval or the second deviation interval; the moving direction, moving speed and moving distance of the wire are determined based on the numerical value and sign of the deviation amount.

[0087] It can be understood that when the deviation is in the large deviation range or the small deviation range, the position of the wire needs to be adjusted. Furthermore, according to the numerical value and sign of the deviation, the moving direction, moving speed and moving distance of the wire are obtained, and the moving direction, moving speed and moving distance of the wire are used as relative position control signals to control the wire feeding mechanism to adjust the position of the wire online, thereby realizing online adjustment of the real-time relative position of the wire and the electron beam, so that the deviation between the real-time relative position of the wire and the electron beam and the target relative position is in the expected range.

[0088] It should be noted that, although the position of the wire needs to be adjusted online when the deviation is in the first deviation range or the second deviation range, the adjustment degrees corresponding to the two deviation ranges are different.

[0089] Specifically, when the deviation is in the first deviation interval, i.e., the large deviation interval, the online control algorithm calculates parameters such as the wire's moving direction, moving speed, and moving distance based on the deviation interval, numerical value, and sign, and the industrial computer outputs the corresponding control signal to the wire feeding mechanism, which adjusts the real-time wire axis position so that its real-time relative position deviation with the electron beam is in the second deviation interval or the third deviation interval.

[0090] When the deviation is in the second deviation interval, that is, the small deviation interval, the online control algorithm also calculates the parameters such as the wire's moving direction, moving speed and moving distance based on the deviation interval, numerical value and sign, and the industrial computer outputs the corresponding control signal to the wire feeding mechanism, which adjusts the real-time wire axis position so that its real-time relative position deviation with the electron beam is less than the set threshold value, so that it is in the third deviation interval.

[0091] In another specific embodiment, if it is determined that the deviation is in the third deviation range, the real-time relative position of the wire and the electron beam is not adjusted.

[0092] It is understandable that when the deviation is in the third deviation interval, i.e., the expected interval, the deviation does not exceed the set threshold, and the real-time relative position of the wire and the electron beam does not need to be adjusted, that is, the current relative position of the wire and the electron beam can be maintained.

[0093] In this embodiment, by determining the deviation range in which the deviation between the real-time relative position of the wire and the electron beam and the target relative position is located, the control parameters of the wire are determined according to the deviation and the deviation range to which it belongs, and then the real-time relative position of the wire and the electron beam is adjusted online according to the control parameters of the wire to ensure that the relative position of the wire and the electron beam does not deviate from the ideal value, thereby effectively improving the stability and continuity of the manufacturing process.

[0094] in addition, Figure 5 The figure shows the overall process of the online control method for the relative position of the wire and the electron beam in the electron beam fuse deposition provided by the present invention.

[0095] like Figure 5 As shown, in step S510, the installation and connection of relevant hardware in the electron beam fused deposition additive manufacturing equipment are performed to complete the hardware construction required for the online control method of the relative position of the wire and the electron beam.

[0096] In step S520, the parameters of the online control system are set. The actual physical size corresponding to a single pixel in the image obtained by the industrial camera should be one order of magnitude or more lower than the set threshold. After the installation position of the industrial camera is determined, the image should be orthodontically corrected. The image acquisition interval should be one order of magnitude or more lower than the time required for the real-time relative position change of the wire and the electron beam to change by a set threshold. The electron beam spot size is experimentally determined and the discrimination area size is determined based on the electron beam energy parameters and substrate position parameters used in the deposition process. The part accuracy, wire diameter, electron beam spot size, molten pool size and other parameters of the deposition process are experimentally determined, and the above-mentioned set threshold is determined in combination with the hardware and algorithm performance of the online control system.

[0097] In step S530 , the target relative position of the wire and the electron beam is pre-calibrated. This step has been described in detail above and will not be elaborated here.

[0098] In step S540 , during the electron beam fuse deposition process, the deviation between the real-time relative position of the wire and the electron beam and the target relative position is controlled online to ensure the stability of the relative position of the wire and the electron beam.

[0099] Figure 6 The figure shows the structure of the online control device for the relative position of the wire and the electron beam in the electron beam fuse deposition provided by the present invention. Figure 6As shown, the device includes: a real-time relative position acquisition module 610, which is used to obtain the real-time relative position of the wire and the electron beam; a position deviation determination module 620, which is used to determine the deviation between the real-time relative position of the wire and the electron beam and the target relative position based on a pre-calibrated target relative position of the wire and the electron beam; a control parameter determination module 630, which is used to determine the control parameters of the wire according to the deviation; and an online control adjustment module 640, which is used to adjust the real-time relative position of the wire and the electron beam online according to the control parameters of the wire.

[0100] In this embodiment, the real-time relative position of the wire and the electron beam is acquired by the real-time relative position acquisition module 610. The position deviation determination module 620 determines the deviation between the real-time relative position of the wire and the electron beam and the target relative position based on the pre-calibrated target relative position of the wire and the electron beam. The control parameter determination module 630 determines the control parameters of the wire based on the deviation, and the online control adjustment module 640 adjusts the real-time relative position of the wire and the electron beam online based on the control parameters of the wire. By real-time monitoring and adjustment of the relative position of the wire and the electron beam during the electron beam fuse deposition process, this device can ensure that the relative position of the wire and the electron beam does not deviate from the ideal value, thereby effectively improving the stability and continuity of the manufacturing process.

[0101] The online control device for the relative position of the wire and the electron beam in electron beam fuse deposition provided in this embodiment can correspond to the online control method for the relative position of the wire and the electron beam in electron beam fuse deposition described above, and will not be repeated here.

[0102] Figure 7 An example of a physical structure diagram of an electronic device is shown below. Figure 7 As shown, the electronic device may include: a processor 710, a communication interface 720, a memory 730 and a communication bus 740, wherein the processor 710, the communication interface 720 and the memory 730 communicate with each other via the communication bus 740. The processor 710 may call the logic instructions in the memory 730 to execute an online control method for the relative position of the wire and the electron beam in electron beam fuse deposition, the method comprising: obtaining the real-time relative position of the wire and the electron beam; determining the deviation between the real-time relative position of the wire and the electron beam and the target relative position based on a pre-calibrated target relative position of the wire and the electron beam; determining the control parameters of the wire based on the deviation; and adjusting the real-time relative position of the wire and the electron beam online based on the control parameters of the wire.

[0103] In addition, the logic instructions in the above-mentioned memory 730 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when sold or used as an independent product. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0104] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in one location or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of the present embodiment. Persons of ordinary skill in the art will be able to understand and implement the present invention without inventive effort.

[0105] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, or of course, by hardware. Based on this understanding, the essence of the above technical solution or the part that contributes to the existing technology can be embodied in the form of a software product. The computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or certain parts of the embodiments.

[0106] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. An online control method for the relative position of a wire and an electron beam in electron beam fuse deposition, characterized in that: include: Pre-calibrating the target relative position of the wire and the electron beam includes: Acquire an initial image of the relative position of the wire and the electron beam; Extracting the melting mark area and the wire material area in the initial image using an image recognition algorithm; Calculating the centroid coordinates of the melting mark region and the wire axis equation corresponding to the wire axis in the wire region; determining a target relative position between the wire and the electron beam based on the centroid coordinates and the wire axis equation; The centroid coordinates in the target relative position are a point on the wire axis equation, the actual physical size corresponding to a single pixel in the initial image is lower than a preset threshold, and the acquisition interval of the initial image is lower than the time required for the real-time relative position of the wire and the electron beam to change by a preset threshold; Obtain the real-time relative position of the wire and the electron beam; Determining a deviation between the real-time relative position of the wire and the electron beam and the target relative position according to a pre-calibrated target relative position of the wire and the electron beam; determining a control parameter of the wire material according to the deviation; The real-time relative position of the wire and the electron beam is adjusted online according to the control parameters of the wire.

2. The method for online control of the relative position between the wire and the electron beam in electron beam fuse deposition according to claim 1, characterized in that: The extracting of the melting mark area and the wire material area in the initial image by using an image recognition algorithm includes: Performing threshold segmentation processing on the enhanced initial image to obtain the melting mark area; Compensating for the low grayscale value area within the melting mark area that is blocked by the wire material to obtain a compensated melting mark area; Performing difference processing on the compensated melting mark area and the melting mark area to obtain the wire area.

3. The method for online control of the relative position of the wire and the electron beam in electron beam fuse deposition according to claim 1, characterized in that: Determining the deviation between the real-time relative position of the wire and the electron beam and the target relative position includes: Determining that any point on the real-time wire axis equation does not belong to the discrimination area, a perpendicular line to the wire axis equation is drawn through the centroid coordinates in the target relative position; Determining the intersection of the vertical line and the real-time wire axis equation; The discrimination area is a circular area with the centroid coordinates in the relative position of the target as the center and the electron beam radius as the radius, and the deviation is the distance between the centroid coordinates and the intersection point.

4. The method for online control of the relative position of the wire and the electron beam in electron beam fuse deposition according to claim 1, characterized in that: Determining the deviation between the real-time relative position of the wire and the electron beam and the target relative position includes: Determine that there is at least one point on the real-time wire axis equation that belongs to the discrimination region, and then identify the point with the maximum grayscale gradient value in the real-time wire axis direction; The discrimination area is a circular area with the centroid coordinates in the target relative position as the center and the electron beam radius as the radius. The deviation is the distance from the point with the maximum grayscale gradient value to the wire axis in the target relative position. The grayscale gradient value is calculated as follows: Where i is the pixel number on the real-time wire axis, x and y are the horizontal and vertical coordinates of the pixel on the real-time wire axis, S is the real-time wire axis, and I is the grayscale value of the pixel.

5. The method for online control of the relative position of the wire and the electron beam in electron beam fuse deposition according to claim 3 or 4, characterized in that: Determining the control parameters of the wire material according to the deviation includes: determining a deviation interval in which the deviation amount lies; A control parameter of the wire is determined according to the deviation amount and the deviation interval.

6. The method for online control of the relative position of the wire and the electron beam in electron beam fuse deposition according to claim 5, characterized in that: Determining the deviation interval in which the deviation is located specifically includes: Determining that any point on the real-time wire axis equation does not belong to the discrimination area, then the deviation amount belongs to the first deviation interval; Determining that at least one point on the real-time wire axis equation belongs to the discrimination area, and the value of the deviation is greater than a set threshold, then the deviation belongs to the second deviation interval; It is determined that at least one point on the real-time wire axis equation belongs to the discrimination area, and the value of the deviation is less than or equal to the set threshold, then the deviation belongs to the third deviation interval.

7. The method for online control of the relative position of the wire and the electron beam in electron beam fuse deposition according to claim 6, characterized in that: Determining the control parameters of the wire material according to the deviation amount and the deviation interval includes: determining whether the deviation is within the first deviation interval or the second deviation interval; Determining the moving direction, moving speed, and moving distance of the wire according to the numerical value and sign of the deviation; or, If it is determined that the deviation is within the third deviation range, no adjustment is performed on the real-time relative position between the wire and the electron beam.

8. An online control device for the relative position of a wire and an electron beam in electron beam fuse deposition, applying the online control method for the relative position of a wire and an electron beam in electron beam fuse deposition according to any one of claims 1 to 7, characterized in that: include: A real-time relative position acquisition module is used to obtain the real-time relative position of the wire and the electron beam; a position deviation determination module, configured to determine a deviation between the real-time relative position of the wire and the electron beam and the target relative position based on a pre-calibrated target relative position of the wire and the electron beam; A control parameter determination module, configured to determine a control parameter of the wire according to the deviation; The online control adjustment module is used to adjust the real-time relative position of the wire and the electron beam online according to the control parameters of the wire.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the steps of the method for online controlling the relative position of the wire and the electron beam in electron beam fuse deposition according to any one of claims 1 to 7 are implemented.

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