An electric arc filament additive manufacturing method and apparatus

Abstract

The application relates to the technical field of aviation manufacturing, and discloses an electric arc fuse additive manufacturing method and device. A rotating clamp and a horizontal overturning clamp are arranged in the field of view of a binocular camera, a binocular camera is used to collect workpiece images to construct a first three-dimensional model, and comparison is made with a theoretical digital model to identify all regions to be processed. Then, the workpiece is fixed on the horizontal overturning clamp, a first region to be processed is determined according to the current rotating angle, and a second region to be processed is obtained by collecting second image information in real time through the binocular camera. A processing path is generated based on the position of the second region to be processed, and an industrial manipulator control device is used for additive manufacturing or welding. Finally, through visual guidance and dynamic path planning, automatic identification and accurate positioning of the region to be processed are realized, the overturning angle is dynamically adjusted, multiple overturning and scanning are carried out, and full coverage processing of all processing regions is completed, so that the problems of low efficiency and unstable quality of traditional electric arc additive manufacturing are solved.

Description

Technical Field

[0001] This invention relates to the field of aerospace manufacturing technology and discloses an electric arc wire additive manufacturing method and apparatus. Background Technology

[0002] Aircraft model development adopts an integrated design and manufacturing parallel mode with short production cycles. The parallel process requires repeated modifications and iterations, which may lead to problems such as manufacturing deviations in parts and cracks during use. Under traditional machining manufacturing methods, these parts are difficult to repair, easily resulting in scrap and remanufacturing, causing material waste, delays, and increased costs.

[0003] Traditional electric arc additive manufacturing is carried out by manual welding or simple programming, which is inefficient, produces inconsistent quality, and cannot handle complex curved surface additive manufacturing and repair problems. Summary of the Invention

[0004] The purpose of this invention is to provide an electric arc wire additive manufacturing method and apparatus that can achieve automatic identification and precise positioning of workpieces through visual guidance and dynamic path planning, and complete full-coverage processing of all processing areas through multiple flips and scans.

[0005] To achieve the above-mentioned technical effects, the technical solution adopted by the present invention is as follows:

[0006] An additive manufacturing method using an electric arc fuse includes:

[0007] The rotary fixture and horizontal flipping fixture used to fix the workpiece to be processed are placed in the field of view of the binocular camera;

[0008] Select a plane on the workpiece to be processed as a reference plane, clamp the workpiece to be processed on a rotary fixture and make the reference plane perpendicular to the rotation center axis of the rotary fixture, use a binocular camera to acquire the first image information of the workpiece to be processed on the rotary fixture, and construct the first three-dimensional model of the workpiece to be processed on the rotary fixture.

[0009] By comparing and analyzing the first three-dimensional model with the theoretical digital model of the workpiece to be processed, the position information of all areas to be processed on the workpiece is obtained.

[0010] The reference surface of the workpiece to be processed is fixed on the working plane of the horizontal flipping fixture. Based on the current rotation angle of the working plane of the horizontal flipping fixture, the position information of the first processing area of ​​the workpiece to be processed under the current rotation angle of the working plane is determined using the first three-dimensional model and all processing areas of the workpiece to be processed.

[0011] The second image information of the horizontal flipping fixture at the current rotation angle is acquired by using a binocular camera, and the position information of the second processing area of ​​the workpiece under the field of view of the binocular camera is obtained by analysis.

[0012] Based on the location information of the second processing area, a path is generated for additive manufacturing or welding of the second processing area of ​​the workpiece to be processed, and an industrial robot is used to control the additive manufacturing device to process the workpiece.

[0013] Based on the relative positional relationship between the first processing area and the second processing area, determine the flipping angle of the horizontal flipping fixture when processing the first processing area outside the second processing area under the current clamping posture;

[0014] The horizontal flipping fixture's flipping frame is flipped according to the flipping angle, and images are acquired using a binocular camera to obtain the area to be processed after the flipping angle, until all areas to be processed under the current clamping posture are completed through additive manufacturing or welding.

[0015] Furthermore, methods for constructing corresponding 3D models using image information acquired by binocular cameras include:

[0016] Using one of the binocular cameras as the main camera, with the center of the main camera lens as the origin, the main optical axis of the main camera as the Z-axis, and the straight lines passing through the origin and parallel to the coordinate axes of the main camera's imaging plate as the X-axis and Y-axis, a camera coordinate system for the binocular camera is constructed.

[0017] Based on the positions of the same location on the two camera imaging plates on the workpiece to be processed, and the camera parameters of the binocular camera, the coordinates of all nodes of the workpiece to be processed in the field of view in the camera coordinate system are analyzed and obtained.

[0018] A world coordinate system O3-X3Y3Z3 is defined using a horizontal flipping fixture. The origin of the world coordinate system is located on the axis of the rotation center of the flipping frame, and the X3 axis of the world coordinate system coincides with the axis of the rotation center, while the Z3 axis is perpendicular to the ground. Using the origin of the world coordinate system as the origin, a workpiece coordinate system O-XYZ is defined on the flipping frame. The X-axis of the workpiece coordinate system coincides with the X3 axis, while the Z-axis is perpendicular to the working plane of the flipping frame.

[0019] By utilizing the principle of translation and rotation transformation of spatial coordinate systems, the coordinates of all nodes of the workpiece to be processed within the field of view of the binocular camera in the camera coordinate system are transformed into coordinates in the world coordinate system.

[0020] Based on the coordinates of the workpiece to be processed in the world coordinate system, a three-dimensional model of the workpiece to be processed is constructed; wherein the image information includes first image information and second image information, and the corresponding three-dimensional model is a first three-dimensional model, or a second three-dimensional model of the workpiece to be processed on the horizontal flip fixture within the field of view of the binocular camera.

[0021] To achieve the above-mentioned technical effects, the present invention also provides an arc fuse additive manufacturing apparatus for implementing the aforementioned arc fuse additive manufacturing method, comprising a rotary fixture, a horizontal flipping fixture, a binocular camera, and:

[0022] The 3D model building module is used to build a first 3D model of the workpiece to be processed on the rotating fixture based on the first image information of the workpiece to be processed on the rotating fixture acquired by the binocular camera, and to build a second 3D model of the workpiece to be processed on the horizontally flipping fixture within the field of view of the binocular camera based on the second image information.

[0023] The comparative analysis module is used to compare and analyze the first three-dimensional model with the theoretical digital model of the workpiece to be processed, and obtain the position information of all areas to be processed of the workpiece.

[0024] The first analysis module is used to determine the position information of the first processing area of ​​the workpiece under the current rotation angle of the working plane of the horizontal flipping fixture, using the first three-dimensional model and all processing areas of the workpiece to be processed.

[0025] The second analysis module is used to acquire second image information of the horizontal flipping fixture at the current rotation angle using a binocular camera, and analyze and obtain the position information of the second processing area of ​​the workpiece under the field of view of the binocular camera.

[0026] The third analysis module is used to determine the flipping angle of the horizontal flipping fixture when processing the first processing area outside the second processing area under the current clamping posture, based on the relative positional relationship between the first processing area and the second processing area.

[0027] The processing control module is used to generate a path for additive manufacturing or welding of the corresponding areas of the workpiece to be processed based on the position information of the second area to be processed and the area to be processed after the flip angle. The industrial robot is used to control the additive manufacturing device to process the workpiece until the additive manufacturing or welding of all areas to be processed under the current clamping posture is completed.

[0028] Furthermore, the horizontal flipping fixture includes a flipping frame and a fixture support arm. The flipping frame is used to provide a forming or repair working plane for the workpiece to be processed and to clamp and fix the workpiece to be processed on the flipping frame. There are two fixture support arms, which are respectively arranged at both ends of the flipping frame, and a horizontal rotating shaft is provided between the two fixture support arms so that the flipping frame can rotate.

[0029] Furthermore, the three-dimensional model construction module includes:

[0030] The camera coordinate system construction unit is used to construct the camera coordinate system of the stereo camera with one of the cameras as the main camera, the center of the main camera lens as the origin, the main optical axis of the main camera as the Z-axis, and the straight lines passing through the origin and parallel to the coordinate axes of the main camera imaging plate as the X-axis and Y-axis, respectively.

[0031] The node coordinate analysis unit is used to analyze and obtain the coordinates of all nodes of the workpiece in the field of view in the camera coordinate system based on the positions of the same position on the two camera imaging plates and the camera parameters of the binocular camera.

[0032] A world coordinate system construction unit is used to define a world coordinate system O3-X3Y3Z3 using a horizontal flipping fixture. The origin of the world coordinate system is located on the axis of the rotation center axis of the flipping frame, and the X3 axis of the world coordinate system coincides with the axis of the rotation center axis, while the Z3 axis is perpendicular to the ground. Using the origin of the world coordinate system as the origin, a workpiece coordinate system O-XYZ is defined on the flipping frame. The X-axis of the workpiece coordinate system coincides with the X3 axis, and the Z-axis is perpendicular to the working plane of the flipping frame.

[0033] The coordinate system transformation unit is used to convert the coordinates of all nodes of the workpiece to be processed in the camera coordinate system into coordinates in the world coordinate system by using the principle of translation and rotation transformation of the spatial coordinate system.

[0034] The three-dimensional model reconstruction unit is used to construct a three-dimensional model of the workpiece to be processed based on the coordinates of the workpiece to be processed in the world coordinate system; wherein the image information includes first image information and second image information, and the corresponding three-dimensional model is a first three-dimensional model, or a second three-dimensional model of the workpiece to be processed on the horizontal flip fixture within the field of view of the binocular camera.

[0035] Furthermore, the rotary fixture includes a rotary base, on which a fixture base plate is provided that conforms to a reference surface.

[0036] Furthermore, a lifting clamping fence is installed on the outer periphery of the clamping base plate. A flexible protective sleeve is detachably installed on the opening edge of the clamping fence. A flexible interface is installed at the end of the flexible protective sleeve away from the clamping fence, which allows the industrial robot to extend into it. The flexible interface is used to detachably fix the industrial robot to the outer shell.

[0037] Furthermore, the rotating base plate of the rotating fixture is also provided with a gas source interface for supplying gas to the closed cavity formed by the flexible protective sleeve, the fixture fence, and the fixture base plate.

[0038] Compared with the prior art, the beneficial effects of this invention are:

[0039] 1. This invention achieves automatic identification and precise positioning of the processing area through visual guidance and dynamic path planning. It completes full-coverage processing of all processing areas by dynamically adjusting the flipping angle and performing multiple flips and scans, thus solving the problems of low efficiency and unstable quality in traditional electric arc additive manufacturing.

[0040] 2. This invention can quickly adapt to iterative changes in aircraft design and manufacturing, reduce parts scrap and costs, and effectively handle defects such as machining deviations, wear and cracks through additive repair function, providing a high-quality and high-efficiency automated solution for aerospace manufacturing. Attached Figure Description

[0041] Figure 1 This is a flowchart of the arc-fuse additive manufacturing method in the embodiment;

[0042] Figure 2 This is a structural block diagram of the arc-fuse additive manufacturing apparatus in the embodiment;

[0043] Figure 3 This is a schematic diagram of the arc-fuse additive manufacturing apparatus in the embodiment;

[0044] Figure 4 This is a schematic diagram of the horizontal flipping fixture in the embodiment;

[0045] Figure 5 This is a schematic diagram of the rotating clamp in the embodiment;

[0046] Figure 6 This is a schematic diagram of the structure when the binocular camera scans the workpiece to be processed on the rotating fixture in the embodiment.

[0047] The components include: 1. Workpiece to be processed; 2. Rotary fixture; 201. Rotary base; 202. Fixture base plate; 203. Fixture enclosure; 204. Flexible protective sleeve; 205. Flexible interface; 206. Air source interface; 3. Horizontal flip fixture; 301. Flip frame; 302. Fixture support arm; 4. Binocular camera; 5. 3D model construction module; 501. Camera coordinate system construction unit; 502. Node coordinate analysis unit; 503. World coordinate system construction unit; 504. Coordinate system transformation unit; 505. 3D model reconstruction unit; 6. Comparison analysis module; 7. First analysis module; 8. Second analysis module; 9. Third analysis module; 10. Processing control module; 11. Industrial robot. Detailed Implementation

[0048] The present invention will now be described in further detail with reference to the embodiments and accompanying drawings. However, this should not be construed as limiting the scope of the above-described subject matter of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0049] Example 1

[0050] See Figures 1 to 6 An additive manufacturing method using an electric arc fuse includes:

[0051] The rotating fixture 2 and the horizontal flipping fixture 3 used to fix the workpiece 1 to be processed are placed in the field of view of the binocular camera 4;

[0052] Select a plane on the workpiece 1 to be processed as a reference plane, clamp the workpiece 1 to be processed on the rotary fixture 2 and make the reference plane perpendicular to the rotation center axis of the rotary fixture 2, use a binocular camera 4 to acquire the first image information of the workpiece 1 to be processed on the rotary fixture 2, and construct the first three-dimensional model of the workpiece 1 to be processed on the rotary fixture 2.

[0053] By comparing and analyzing the first three-dimensional model with the theoretical digital model of the workpiece 1 to be processed, the position information of all areas to be processed in the workpiece 1 is obtained.

[0054] The reference surface of the workpiece 1 to be processed is fixed on the working plane of the horizontal flipping fixture 3. Based on the current rotation angle of the working plane of the horizontal flipping fixture 3, the position information of the first processing area of ​​the workpiece 1 to be processed under the current rotation angle of the working plane is determined using the first three-dimensional model and all processing areas of the workpiece 1 to be processed.

[0055] The second image information of the horizontal flipping fixture 3 at the current rotation angle is acquired by using the binocular camera 4, and the position information of the second processing area of ​​the workpiece 1 under the field of view of the binocular camera 4 is obtained by analysis.

[0056] Based on the location information of the second processing area, a path is generated for additive manufacturing or welding of the second processing area of ​​the workpiece 1 to be processed, and the industrial robot 11 is used to control the additive manufacturing device to process the workpiece 1 to be processed.

[0057] Based on the relative positional relationship between the first processing area and the second processing area, determine the flipping angle of the horizontal flipping fixture 3 when processing the first processing area outside the second processing area under the current clamping posture;

[0058] The horizontal flipping fixture 3 flips the flipping frame 301 according to the flipping angle, and uses a binocular camera 4 to acquire images to obtain the area to be processed after the flipping angle, until all areas to be processed under the current clamping posture are completed for additive manufacturing or welding.

[0059] In this embodiment, by placing the rotating fixture 2 and the horizontal flipping fixture 3 within the field of view of the binocular camera 4, the binocular camera 4 acquires images of the workpiece to construct a first 3D model, which is then compared with a theoretical digital model to identify all areas to be processed. The workpiece is then fixed on the horizontal flipping fixture 3, and the first area to be processed is determined based on the current rotation angle. The binocular camera 4 then acquires second image information in real time to obtain the second area to be processed. A processing path is generated based on the position of the second area to be processed, and additive manufacturing or welding is performed by the industrial robot 11 control device. Finally, the flipping angle is dynamically adjusted according to the inclusion relationship and relative positional relationship between the first and second areas to be processed, and full coverage processing of all areas is completed through multiple flips and scans. This embodiment achieves automatic workpiece identification and precise positioning through visual guidance and dynamic path planning, solving the problems of low efficiency and unstable quality in traditional arc additive manufacturing. It can quickly adapt to iterative changes in aircraft design and manufacturing, reducing part scrap and costs. Simultaneously, the additive repair function effectively handles defects such as machining deviations, wear, and cracks, providing a high-quality, high-efficiency automated solution for aerospace manufacturing.

[0060] Based on the same inventive concept, this embodiment also provides an arc fuse additive manufacturing apparatus for implementing the aforementioned arc fuse additive manufacturing method, including a rotary fixture 2, a horizontal flipping fixture 3, a binocular camera 4, and:

[0061] The 3D model construction module 5 is used to construct a first 3D model of the workpiece 1 to be processed on the rotating fixture 2 based on the first image information of the workpiece 1 to be processed on the rotating fixture 2 acquired by the binocular camera 4, and to construct a second 3D model of the workpiece 1 to be processed on the horizontally flipping fixture 3 within the field of view of the binocular camera 4 based on the second image information.

[0062] The comparison and analysis module 6 is used to compare and analyze the first three-dimensional model with the theoretical digital model of the workpiece 1 to obtain the position information of all areas to be processed in the workpiece 1.

[0063] The first analysis module 7 is used to determine the position information of the first processing area of ​​the workpiece 1 under the current rotation angle of the working plane of the horizontal flipping fixture 3, using the first three-dimensional model and all processing areas of the workpiece 1.

[0064] The second analysis module 8 is used to acquire second image information of the horizontal flipping fixture 3 at the current rotation angle using the binocular camera 4, and analyze and obtain the position information of the second processing area of ​​the workpiece 1 under the field of view of the binocular camera 4.

[0065] The third analysis module 9 is used to determine the flipping angle of the horizontal flipping fixture 3 when processing the first processing area outside the second processing area under the current clamping posture, based on the relative positional relationship between the first processing area and the second processing area.

[0066] The processing control module 10 is used to generate a path for additive manufacturing or welding of the corresponding areas to be processed in the workpiece 1 based on the position information of the second area to be processed and the area to be processed after the flip angle. The industrial robot 11 controls the additive manufacturing device to process the workpiece 1 until the additive manufacturing or welding of all areas to be processed in the current clamping posture is completed.

[0067] In this embodiment, the horizontal flipping fixture 3 includes a flipping frame 301 and fixture arms 302. The flipping frame 301 provides a forming or repair working surface for the workpiece 1 to be processed and clamps and fixes the workpiece 1 to be processed on the flipping frame 301. There are two fixture arms 302, respectively disposed at both ends of the flipping frame 301, and a horizontal pivot is provided between the two fixture arms 302 for the flipping frame 301 to rotate. Under the control of the actuation mechanism, the flipping frame 301 can rotate flexibly around the horizontal pivot, thereby changing the angle of the working surface to meet the requirements of the workpiece posture during processing of different processing areas.

[0068] The 3D model construction module 5 in this embodiment includes:

[0069] The camera coordinate system construction unit 501 is used to construct the camera coordinate system of the binocular camera 4 with one of the cameras in the binocular camera 4 as the main camera, the center of the main camera lens as the origin, the main optical axis of the main camera as the Z axis, and the straight lines passing through the origin and parallel to the coordinate axes of the main camera imaging plate as the X axis and Y axis, respectively.

[0070] The node coordinate analysis unit 502 is used to analyze and obtain the coordinates of all nodes of the workpiece 1 in the field of view in the camera coordinate system based on the positions of the same position on the two camera imaging plates and the camera parameters of the binocular camera 4.

[0071] The world coordinate system construction unit 503 is used to define a world coordinate system O3-X3Y3Z3 with the horizontal flipping fixture 3. The origin of the world coordinate system is located on the axis of the rotation center axis of the flipping frame 301, and the X3 axis of the world coordinate system coincides with the axis of the rotation center axis, while the Z3 axis is perpendicular to the ground. With the origin of the world coordinate system as the origin, a workpiece coordinate system O-XYZ is defined on the flipping frame 301. The X-axis of the workpiece coordinate system coincides with the X3 axis, while the Z-axis is perpendicular to the working plane of the flipping frame 301.

[0072] The coordinate system transformation unit 504 is used to transform the coordinates of all nodes of the workpiece 1 in the field of view of the binocular camera 4 in the camera coordinate system into coordinates in the world coordinate system by using the principle of translation and rotation transformation of the spatial coordinate system.

[0073] The three-dimensional model reconstruction unit 505 is used to construct a three-dimensional model of the workpiece 1 to be processed based on the coordinates of the workpiece 1 to be processed in the world coordinate system; wherein the image information includes first image information and second image information, and the corresponding three-dimensional model is a first three-dimensional model, or a second three-dimensional model of the workpiece 1 to be processed on the horizontal flip fixture 3 within the field of view of the binocular camera 4.

[0074] In this embodiment, the rotating fixture 2 includes a rotating base 201, on which a fixture base plate 202 is provided that is in contact with a reference surface.

[0075] A lifting clamp fence 203 is also installed on the outer periphery of the clamp base plate 202. A flexible protective sleeve 204 is detachably installed on the opening edge of the clamp fence 203. A flexible interface 205 is installed at the end of the flexible protective sleeve 204 away from the clamp fence 203, into which the industrial robot 11 can extend. The flexible interface 205 is used to detachably fix the industrial robot 11 to the outer shell.

[0076] The rotating fixture 2 has two usage scenarios: one is to work with the binocular camera 4 to perform rotational scanning, in which the fixture fence 203 is in a retracted state to provide a scanning field of view; the other is to work with the industrial robot 11 to perform parts repair and processing during the rotation process.

[0077] In some other embodiments, when the rotary fixture 2 is used in conjunction with the industrial robot 11 for parts repair and processing, the rotary base plate of the rotary fixture 2 is also provided with a gas source interface 206 for supplying gas to the closed cavity formed by the flexible protective sleeve 204, the fixture fence 203, and the fixture base plate 202. The gas source interface 206 is connected to an external gas source through a gas pipe, and the pressure and flow rate of the supplied gas can be adjusted according to actual needs. The supplied gas can be an inert gas, such as nitrogen or argon, which provides a protective atmosphere for the workpiece 1 to be processed during the processing, preventing adverse reactions such as oxidation of the workpiece under high temperature. Under the action of the gas, the closed cavity can better fix the workpiece 1 to be processed, reduce the shaking and displacement of the workpiece during the processing, and improve the processing accuracy and stability. At the same time, the flexible interface 205 of the flexible protective sleeve 204 is detachably fixed to the outer shell of the industrial robot 11, which facilitates various operations of the industrial robot 11 on the workpiece on the rotary fixture 2, such as gripping, carrying, and adjusting the position, thereby improving the automation level and production efficiency of the entire manufacturing process.

[0078] Example 2

[0079] See Figures 1 to 6 An additive manufacturing method using an electric arc fuse includes:

[0080] Step 1: Place the rotating fixture 2 and the horizontal flipping fixture 3, which are used to fix the workpiece 1 to be processed, in the field of view of the binocular camera 4.

[0081] Step 2: Define a world coordinate system O3-X3Y3Z3 using the horizontal flipping fixture 3. The origin of the world coordinate system is located on the axis of the rotation center axis of the flipping frame 301, and the X3 axis of the world coordinate system coincides with the axis of the rotation center axis, while the Z3 axis is perpendicular to the ground.

[0082] With the origin of the world coordinate system as the origin, a workpiece coordinate system O-XYZ is defined on the flipping frame 301. The X-axis of the workpiece coordinate system coincides with the X3-axis, and the Z-axis is perpendicular to the working plane of the flipping frame 301.

[0083] Establish a coordinate system O1-X1Y1Z1 on the rotary fixture 2. The origin O1 is located at the rotation center of the working plane of the rotary fixture 2. When the rotary fixture 2 is in the zero position, the X1 axis is parallel to the X3 axis of O3-X3Y3Z3, the Y1 axis is parallel to the Y3 axis of O3-X3Y3Z3, and the Z1 axis is parallel to the Z3 axis of O3-X3Y3Z3. The Z axis is perpendicular to the working plane of the rotary fixture 2.

[0084] Step 3: Select a plane on the workpiece 1 to be processed as a reference plane, clamp the workpiece 1 to be processed on the rotary fixture 2 and make the reference plane perpendicular to the rotation center axis of the rotary fixture 2, use the binocular camera 4 to acquire the first image information of the workpiece 1 to be processed on the rotary fixture 2, and construct the first three-dimensional model of the workpiece 1 to be processed on the rotary fixture 2.

[0085] In this embodiment, the rotating fixture 2 is first rotated to the zero position, and then the workpiece 1 to be processed is placed on the rotating fixture 2. The rotating fixture 2 drives the workpiece 1 to be processed to rotate. The binocular camera 4 acquires the first image information of the workpiece 1 to be processed on the rotating fixture 2. By stitching the point cloud of the images during the dynamic scanning process of the binocular camera 4, point cloud data with coordinate values ​​of the workpiece 1 to be processed in the coordinate system O1-X1Y1Z1 is obtained, realizing the initial scanning modeling of the workpiece and obtaining the first three-dimensional model of the workpiece 1 to be processed on the rotating fixture 2.

[0086] Step 4: Compare and analyze the first 3D model with the theoretical digital model of the workpiece 1 to obtain the position information of all areas to be processed in the workpiece 1.

[0087] In this embodiment, by comparing the collected first three-dimensional model data with the theoretical digital model of the workpiece 1 to be processed, the differences between the two are identified. The positions corresponding to these differences are the position information of all areas to be processed in the workpiece 1, providing accurate positioning guidance for subsequent processing operations.

[0088] Step 5: Fix the reference surface of the workpiece 1 to be processed on the working plane of the horizontal flipping fixture 3. Based on the current rotation angle of the working plane of the horizontal flipping fixture 3, and using the first three-dimensional model and all the areas to be processed of the workpiece 1, determine the position information of the first area to be processed of the workpiece 1 under the current rotation angle of the working plane; the specific operation is as follows:

[0089] 5.1 Using one of the cameras in the binocular camera 4 as the main camera, with the center of the main camera lens as the origin O, the main optical axis of the main camera as the Z-axis, and the straight lines passing through the origin and parallel to the coordinate axes of the main camera imaging plate as the X-axis and Y-axis respectively, the camera coordinate system O-XYZ of the binocular camera 4 is constructed.

[0090] 5.2 Based on the positions of the same location on the imaging plates of the two cameras on the workpiece 1 to be processed, and the camera parameters of the binocular camera 4, the coordinates of all nodes of the workpiece 1 within the field of view in the camera coordinate system are analyzed and obtained; specifically:

[0091] The distance between the centers of the two lenses of the binocular camera 4 is the baseline distance B. The distance from the imaging plate to the center of the camera lens is the focal length f of the camera. P is any point on the object within the camera's field of view. The corresponding pixel points of point P on the imaging plates of the two lenses are point p1 and point p2, respectively. Coordinate systems b1-x1y1 and b2-x2y2 are established on the imaging plates of the two lenses, respectively. The coordinates of the pixel points of point P on the two imaging plates are p1(x1, y1) and p2(x2, y2), respectively. The coordinates of point P in the camera coordinate system a1-x1y1z1 and a2-x2y2z2 are P(X1, Y1, Z1) and P(X1, Y1-B, Z1), respectively. According to the principle of pinhole imaging, ...

[0092]

[0093] By combining the above equations, we can obtain the coordinates of any point P in the camera's field of view in the camera coordinate system a1-x1y1z1 as [x1Z1 / f, y1Z1 / f, fB / (y1-y2)].

[0094] 5.3 Point cloud data in the camera coordinate system needs to be converted into point cloud data in the workpiece coordinate system through geometric coordinate transformation in order to achieve registration and alignment between the digital model and the actual workpiece. The registration and alignment process between the digital model and the actual workpiece is as follows: coordinate system a1-x1y1z1 is the camera coordinate system, and O-XYZ is the workpiece coordinate system. After a translation transformation, coordinate system a1-x1y1z1 is made so that the origin a1 of the camera coordinate system coincides with the far point O of the workpiece coordinate system, forming coordinate system O-x1y1z1 whose coordinate axes are parallel to the axes of a1-x1y1z1. The translation vector of this process is T=[X0, Y0, Z0]. The translated coordinate system O-x1y1z1 is rotated around the origin O until its coordinate axes coincide with the workpiece coordinate system O-XYZ, thus realizing the transformation of the point cloud from the camera coordinate system to the workpiece coordinate system. During the rotation transformation, the points are rotated around the X, Y, and Z axes by angles ψ1, ψ2, and ψ3, respectively. Let the rotation matrix be R. Then, the coordinates of the point cloud data in the workpiece coordinate system are...

[0095] [X, Y, Z]=[x1Z1 / f, y1Z1 / f, fB / (y1-y2)]R+[X0, Y0, Z0]

[0096] Where R = R(ψ1)R(ψ2)R(ψ3)

[0097] .

[0098] 5.4 Based on the coordinates of the workpiece 1 to be processed in the workpiece coordinate system, construct the first three-dimensional model of the workpiece 1 to be processed; specifically, the transformation relationship can be expressed by the formula:

[0099]

[0100] According to the above algorithm, the fixed coordinate system O-X3Y3Z3 established at the camera end can be aligned with the workpiece coordinate system O-XYZ, thereby establishing the workpiece coordinate system O-XYZ on the binocular camera 4. At this point, the registration and alignment between the physical workpiece and the camera scan point cloud is completed. The point cloud information of the workpiece to be repaired or welded can be obtained according to the point cloud data scanned by the camera, and the shape of the workpiece can be reconstructed according to the scan points.

[0101] Step 6: Use the binocular camera 4 to acquire the second image information of the horizontal flip fixture 3 at the current rotation angle, and analyze to obtain the position information of the second processing area of ​​the workpiece 1 under the field of view of the binocular camera 4;

[0102] In this embodiment, the actual scanned point cloud data in the workpiece coordinate system is compared with all the point cloud data scanned on the rotating fixture 2 to determine the visible and reachable processing parts at the current workstation.

[0103] It should be noted that the above coordinate system transformation is a technical means that can be known to those skilled in the art, and the specific details of the process will not be elaborated here.

[0104] Step 7: Based on the location information of the second processing area, generate a path for additive manufacturing or welding of the second processing area of ​​the workpiece 1 to be processed, and use the industrial robot 11 to control the additive manufacturing device to process the workpiece 1 to be processed.

[0105] In this embodiment, the theoretical digital model of the product to be processed is first imported into the industrial control computer host. The theoretical digital model and the second processing area are analyzed and processed by the processing software (to determine the additive manufacturing process such as adding support, plugging holes, and increasing process allowance in the second processing area). The theoretical digital model is processed into a three-dimensional model that matches the corresponding process of additive manufacturing, combination manufacturing, additive repair, or arc welding. Then, the arc additive process parameters (current, voltage, wire feed speed, welding speed, etc.) are configured through the display. Next, the additive manufacturing path is planned through the software according to the additive manufacturing process, and simulation processing and process optimization are performed on the display. Then, additive manufacturing, combination manufacturing, additive repair, or arc welding is performed in the flipping fixture according to the process parameters and processing path verified by simulation. Finally, the metal part of the second processing area is formed.

[0106] Step 8: Based on the relative positional relationship between the first processing area and the second processing area, determine the flipping angle of the horizontal flipping fixture 3 when processing the first processing area outside the second processing area under the current clamping posture;

[0107] By further comparing whether each processing position in the second processing area covers all processing positions in the first processing area, if so, it is determined that the processing is completed at the current flip angle of the flip fixture; otherwise, proceed to step nine.

[0108] Step 9: Flip the flipping frame 301 of the horizontal flipping fixture 3 according to the flipping angle, use a binocular camera 4 to acquire images, obtain the area to be processed after the flipping angle, and repeat the relevant process flow of Steps 7 to 8 until all areas to be processed under the current clamping posture are completed in additive manufacturing or welding.

[0109] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for additive manufacturing of electric arc fuse wire, characterized in that, include: The rotary fixture and horizontal flipping fixture used to fix the workpiece to be processed are placed in the field of view of the binocular camera; Select a plane on the workpiece to be processed as a reference plane, clamp the workpiece to be processed on a rotary fixture and make the reference plane perpendicular to the rotation center axis of the rotary fixture, use a binocular camera to acquire the first image information of the workpiece to be processed on the rotary fixture, and construct the first three-dimensional model of the workpiece to be processed on the rotary fixture. By comparing and analyzing the first three-dimensional model with the theoretical digital model of the workpiece to be processed, the position information of all areas to be processed on the workpiece is obtained. The reference surface of the workpiece to be processed is fixed on the working plane of the horizontal flipping fixture. Based on the current rotation angle of the working plane of the horizontal flipping fixture, the position information of the first processing area of ​​the workpiece to be processed under the current rotation angle of the working plane is determined using the first three-dimensional model and all processing areas of the workpiece to be processed. The second image information of the horizontal flipping fixture at the current rotation angle is acquired by using a binocular camera, and the position information of the second processing area of ​​the workpiece under the field of view of the binocular camera is obtained by analysis. Based on the location information of the second processing area, a path is generated for additive manufacturing or welding of the second processing area of ​​the workpiece to be processed, and an industrial robot is used to control the additive manufacturing device to process the workpiece. Based on the relative positional relationship between the first processing area and the second processing area, determine the flipping angle of the horizontal flipping fixture when processing the first processing area outside the second processing area under the current clamping posture; The horizontal flipping fixture's flipping frame is flipped according to the flipping angle, and images are acquired using a binocular camera to obtain the area to be processed after the flipping angle, until all areas to be processed under the current clamping posture are completed through additive manufacturing or welding.

2. The method for additive manufacturing of electric arc-fused wire according to claim 1, characterized in that, Methods for constructing corresponding 3D models using image information acquired by binocular cameras include: Using one of the binocular cameras as the main camera, with the center of the main camera lens as the origin, the main optical axis of the main camera as the Z-axis, and the straight lines passing through the origin and parallel to the coordinate axes of the main camera's imaging plate as the X-axis and Y-axis, a camera coordinate system for the binocular camera is constructed. Based on the positions of the same location on the two camera imaging plates on the workpiece to be processed, and the camera parameters of the binocular camera, the coordinates of all nodes of the workpiece to be processed in the field of view in the camera coordinate system are analyzed and obtained. A world coordinate system O3-X3Y3Z3 is defined using a horizontal flipping fixture. The origin of the world coordinate system is located on the axis of the rotation center of the flipping frame, and the X3 axis of the world coordinate system coincides with the axis of the rotation center, while the Z3 axis is perpendicular to the ground. Using the origin of the world coordinate system as the origin, a workpiece coordinate system O-XYZ is defined on the flipping frame. The X-axis of the workpiece coordinate system coincides with the X3 axis, while the Z-axis is perpendicular to the working plane of the flipping frame. By utilizing the principle of translation and rotation transformation of spatial coordinate systems, the coordinates of all nodes of the workpiece to be processed within the field of view of the binocular camera in the camera coordinate system are transformed into coordinates in the world coordinate system. Based on the coordinates of the workpiece to be processed in the world coordinate system, a three-dimensional model of the workpiece to be processed is constructed; wherein the image information includes first image information and second image information, and the corresponding three-dimensional model is a first three-dimensional model, or a second three-dimensional model of the workpiece to be processed on the horizontal flip fixture within the field of view of the binocular camera.

3. An electric arc wire additive manufacturing apparatus for implementing the electric arc wire additive manufacturing method according to claim 1 or 2, characterized in that, Including rotary clamps, horizontal flip clamps, binocular cameras, and: The 3D model building module is used to build a first 3D model of the workpiece to be processed on the rotating fixture based on the first image information of the workpiece to be processed on the rotating fixture acquired by the binocular camera, and to build a second 3D model of the workpiece to be processed on the horizontally flipping fixture within the field of view of the binocular camera based on the second image information. The comparative analysis module is used to compare and analyze the first three-dimensional model with the theoretical digital model of the workpiece to be processed, and obtain the position information of all areas to be processed of the workpiece. The first analysis module is used to determine the position information of the first processing area of ​​the workpiece under the current rotation angle of the working plane of the horizontal flipping fixture, using the first three-dimensional model and all processing areas of the workpiece to be processed. The second analysis module is used to acquire second image information of the horizontal flipping fixture at the current rotation angle using a binocular camera, and analyze and obtain the position information of the second processing area of ​​the workpiece under the field of view of the binocular camera. The third analysis module is used to determine the flipping angle of the horizontal flipping fixture when processing the first processing area outside the second processing area under the current clamping posture, based on the relative positional relationship between the first processing area and the second processing area. The processing control module is used to generate a path for additive manufacturing or welding of the corresponding areas of the workpiece to be processed based on the position information of the second area to be processed and the area to be processed after the flip angle. The industrial robot is used to control the additive manufacturing device to process the workpiece until the additive manufacturing or welding of all areas to be processed under the current clamping posture is completed.

4. The arc-fuse additive manufacturing apparatus according to claim 3, characterized in that, The horizontal flipping fixture includes a flipping frame and a fixture support arm. The flipping frame is used to provide a forming or repair working surface for the workpiece to be processed and to clamp and fix the workpiece to be processed on the flipping frame. There are two fixture support arms, which are respectively set at both ends of the flipping frame. A horizontal rotating shaft is provided between the two fixture support arms so that the flipping frame can rotate.

5. The arc-fuse additive manufacturing apparatus according to claim 4, characterized in that, The 3D model construction module includes: The camera coordinate system construction unit is used to construct the camera coordinate system of the stereo camera with one of the cameras as the main camera, the center of the main camera lens as the origin, the main optical axis of the main camera as the Z-axis, and the straight lines passing through the origin and parallel to the coordinate axes of the main camera imaging plate as the X-axis and Y-axis, respectively. The node coordinate analysis unit is used to analyze and obtain the coordinates of all nodes of the workpiece in the field of view in the camera coordinate system based on the positions of the same position on the two camera imaging plates and the camera parameters of the binocular camera. A world coordinate system construction unit is used to define a world coordinate system O3-X3Y3Z3 using a horizontal flipping fixture. The origin of the world coordinate system is located on the axis of the rotation center axis of the flipping frame, and the X3 axis of the world coordinate system coincides with the axis of the rotation center axis, while the Z3 axis is perpendicular to the ground. Using the origin of the world coordinate system as the origin, a workpiece coordinate system O-XYZ is defined on the flipping frame. The X-axis of the workpiece coordinate system coincides with the X3 axis, and the Z-axis is perpendicular to the working plane of the flipping frame. The coordinate system transformation unit is used to convert the coordinates of all nodes of the workpiece to be processed in the camera coordinate system into coordinates in the world coordinate system by using the principle of translation and rotation transformation of the spatial coordinate system. The three-dimensional model reconstruction unit is used to construct a three-dimensional model of the workpiece to be processed based on the coordinates of the workpiece to be processed in the world coordinate system; wherein the image information includes first image information and second image information, and the corresponding three-dimensional model is a first three-dimensional model, or a second three-dimensional model of the workpiece to be processed on the horizontal flip fixture within the field of view of the binocular camera.

6. The arc-fuse additive manufacturing apparatus according to claim 3, characterized in that, The rotary fixture includes a rotary base, on which a fixture base plate is provided that conforms to a reference surface.

7. The arc-fuse additive manufacturing apparatus according to claim 6, characterized in that, The outer periphery of the clamp base plate is also equipped with a lifting clamp fence. The opening edge of the clamp fence is detachably equipped with a flexible protective sleeve. At the end of the flexible protective sleeve away from the clamp fence, a flexible interface is installed for the industrial robot to extend into. The flexible interface is used to detachably fix the industrial robot to the outer shell.

8. The arc-fuse additive manufacturing apparatus according to claim 7, characterized in that, The rotating base plate of the rotating fixture is also provided with a gas source interface for supplying gas to the closed cavity formed by the flexible protective sleeve, the fixture fence, and the fixture base plate.

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