A seam processing method suitable for curved surface laser etching

Abstract

The application provides a joint processing method suitable for curved surface laser etching, and relates to the technical field of laser processing. The method comprises the following steps: according to the starting point, the ending point and the curved surface normal vector of each division line of a curved surface part model, the motion trajectory of each division line suitable for the curved surface part can be determined, the motion trajectory of the residual metal of the curved surface part is determined in the motion trajectory of each division line, the machine tool five-axis motion suitable for the motion trajectory of the residual metal of the curved surface part is carried out, laser etching is carried out according to the processing trajectory of the scanning galvanometer, and the residual metal of the curved surface part is removed to complete the joint processing of the curved surface part. The determined motion trajectory of the residual metal is fitted to the curved surface of the curved surface part, laser etching is carried out through the motion trajectory fitted to the curved surface, the residual metal of the curved surface part can be removed by fitting to the curved surface, and the method can be better suitable for the joint processing of the curved surface laser etching of the super-amplitude curved surface.

Description

Technical Field

[0001] This invention relates to the field of laser processing technology, and in particular to a seam processing method suitable for laser etching of curved surfaces. Background Technology

[0002] In the fields of aviation, aerospace, and marine engineering, there is a need to manufacture critical components such as conformal antennas and radomes. These critical components are large-format curved parts, and the machining of these large-format curved parts involves the processing of microstructures with large dimensions and complex curvature variations. Microstructure machining utilizes laser etching to subtractively process the metal layer on the surface of the curved part, etching away a portion of the metal layer while retaining another portion. The retained metal layer forms the microstructure required for the curved part. Because the etched pattern size of the large-format curved part exceeds the processing area of ​​the galvanometer, the entire large-format curved part cannot be machined in a single etching operation. Therefore, a pattern segmentation etching method is used to process the curved part. The large-format pattern corresponding to the large-format curved part is divided into multiple machinable smaller patterns, and each segment is processed individually to achieve the overall machining of the large-format curved part.

[0003] In the overall machining of large-format curved parts, the large-format graphic is often broken down into multiple graphics, which are then machined separately. This process requires first moving the optical (laser etching) system to a designated position using machine tool movement before machining each graphic. However, the movement of the laser etching system is affected by the machine tool's precision, resulting in positional deviations. This leads to discrepancies in the actual machined graphics, causing "seams" and "over-seams" between the divided graphics. Over-seammed sections are usable, but the seams are considered incomplete, leaving metal residue in the laser-etched area. This residue can create electrical connections between the remaining metal layers, damaging the part's microstructure. Therefore, it is necessary to process the seams in the curved surface laser etching.

[0004] Currently, the processing of seams in laser etching is typically achieved through a splicing device consisting of an image recognition system, a transmission mechanism, and a laser etching machine. This device identifies and marks the etched product surfaces, calculates the angular offset between the current etched surface and the next and previous etched surfaces, and then etches the next surface. By obtaining the splicing position between the current and next processing surfaces, the next processing surface is placed within the range of the current processing surface, thus achieving the seam processing of laser etching. However, existing laser etching seam processing technologies only achieve the splicing of laser-etched parts with large planar surfaces. They are not applicable to the splicing of laser-etched curved parts with large planar surfaces; in other words, they are not suitable for the splicing of laser-etched curved parts with large planar surfaces. Summary of the Invention

[0005] The purpose of this invention is to provide a seam processing method suitable for curved surface laser etching, solving the problem that the existing technology is not suitable for seam processing of ultra-large curved surface laser etching.

[0006] To address the aforementioned technical problems, the embodiments of the present invention provide the following technical solutions:

[0007] The first aspect of this invention provides a method for machining seams in laser etching of curved surfaces, the method comprising:

[0008] Obtain the surface part model that has been laser etched. The surface part model is a model that has been graphic segmented before laser etching is completed. The surface part model includes multiple segmentation lines.

[0009] Extract multiple segmentation lines and determine the motion trajectory of each segmentation line based on its starting point, ending point, and surface normal vector.

[0010] Under the vision system of the machine tool, the five-axis motion of the machine tool is performed according to the motion trajectory of each dividing line, and the motion trajectory of the residual metal is determined in the motion trajectory of each dividing line. The processing trajectory of the scanning galvanometer is generated based on the width of the residual metal.

[0011] In the state of the laser etching system of the machine tool, the five-axis motion of the machine tool is performed according to the motion trajectory of the metal residue, and at the same time, laser etching is performed according to the processing trajectory of the scanning galvanometer to remove the residual metal and complete the seam processing of the curved part.

[0012] In some modified embodiments of the first aspect of the present invention, multiple segmentation lines are extracted, and the motion trajectory of each segmentation line is determined based on its starting point, ending point, and surface normal vector, including:

[0013] Extract multiple dividing lines, each including a first endpoint and a second endpoint;

[0014] The first endpoint of each dividing line is taken as the starting point of the movement, and the second endpoint of each dividing line is taken as the ending point of the movement;

[0015] Using the direction of the surface normal vector perpendicular to the surface where each dividing line is located as the direction of motion, the motion trajectory from the starting point to the ending point of each dividing line according to the direction of motion is determined as the motion trajectory of each dividing line.

[0016] In some modified embodiments of the first aspect of the invention, the method further includes, before extracting the multiple dividing lines:

[0017] The starting and ending coordinates of multiple dividing lines are identified separately.

[0018] Among multiple dividing lines, filter out those that have the same starting coordinates and the same ending coordinates;

[0019] Remove duplicates from the selected dividing lines.

[0020] In some modified embodiments of the first aspect of the present invention, in the state of the machine tool's vision system, the machine tool performs five-axis motion according to the motion trajectory of each dividing line, and determines the motion trajectory containing residual metal in the motion trajectory of each dividing line, and generates the processing trajectory of the scanning galvanometer based on the width of the residual metal, including:

[0021] Under the vision system of the machine tool, the five-axis motion of the machine tool is performed according to the motion trajectory of each segmentation line, and the gray value of the motion trajectory of each segmentation line is determined in the motion trajectory of each segmentation line.

[0022] The gray values ​​of the motion trajectories of each segmentation line are compared with the preset gray values ​​to identify motion trajectories that differ from the preset gray values, and these motion trajectories are identified as those containing residual metal.

[0023] The machining trajectory of the scanning galvanometer is generated based on the width of the residual metal.

[0024] In some modified embodiments of the first aspect of the invention, generating the processing trajectory of the scanning galvanometer based on the width of the residual metal includes:

[0025] Determine the ratio of the pixel blocks in the image of the curved part model acquired by the vision system to the actual size of the curved part;

[0026] Acquire images of motion trajectories containing residual metal, and identify pixel blocks of residual metal within the images;

[0027] Based on the pixel blocks and ratios of the residual metal in the image, the width of the residual metal is calculated, and the processing trajectory of the scanning galvanometer is generated using the width of the residual metal.

[0028] In some modified embodiments of the first aspect of the present invention, after comparing the grayscale value of the motion trajectory of each dividing line with a preset grayscale value to determine the motion trajectory that differs from the preset grayscale value, and determining the motion trajectory that differs from the preset grayscale value as the motion trajectory containing residual metal, the method further includes:

[0029] Determine the preset start and preset end points of the trajectory where residual metal exists;

[0030] Mark the preset start point and preset end point to obtain the marked preset start point and marked preset end point.

[0031] In some modified embodiments of the first aspect of the present invention, in the state of the laser etching system of the machine tool, the five-axis motion of the machine tool is performed according to the motion trajectory of the metal residue, and laser etching is performed simultaneously according to the processing trajectory of the scanning galvanometer, so as to remove the residual metal and complete the seam processing of the curved part, including:

[0032] In the state of the laser etching system of the machine tool, control the scanning galvanometer to move to the preset starting point of the mark;

[0033] The center point of the laser galvanometer etching area is controlled to be on the surface of the curved part, and the machine tool performs five-axis motion along the motion trajectory of the metal residue.

[0034] Simultaneously, the laser galvanometer is controlled to perform laser etching by scanning the processing trajectory of the galvanometer, so as to remove the residual metal in the movement trajectory where there is residual metal.

[0035] When the scanning galvanometer is detected to have moved to the preset endpoint marked, the scanning galvanometer is controlled to stop moving and the laser galvanometer is controlled to stop laser etching.

[0036] The scanning galvanometer is controlled to move to the preset starting point marked by the next motion trajectory containing residual metal, until all residual metal in the motion trajectory containing residual metal is removed, so as to complete the seam processing of the curved part.

[0037] In some modified embodiments of the first aspect of the present invention, after controlling the scanning galvanometer to stop moving and controlling the laser galvanometer to stop laser etching when the scanning galvanometer is detected to have moved to the preset endpoint of the mark, the method further includes:

[0038] Determine if there is a movement trajectory of residual metal;

[0039] If so, control the scanning galvanometer to move to the preset starting point marked by the next motion trajectory where residual metal exists;

[0040] If not, the movement of the scanning galvanometer is not controlled, and the seam processing of the curved parts is completed.

[0041] In some modified embodiments of the first aspect of the present invention, the direction of the surface normal vector is perpendicular to the surface direction of the surface part, and the direction of the surface normal vector points from the inside of the surface part to the outside.

[0042] In some modified embodiments of the first aspect of the invention, before obtaining a model of the laser-etched curved surface part, the method further includes:

[0043] Based on the galvanometer processing area and focal depth, the model of the curved surface part to be etched is graphically segmented, and the center point and surface normal vector of each segmented region are calculated.

[0044] Determine the processing trajectory of the scanning galvanometer in each segmented region;

[0045] The center point and the surface normal vector are used as the target point positions for the five-axis motion of the machine tool. The machining trajectory is used as the machining pattern for each segmented area for scanning and machining to complete the laser etching of the curved part. Compared with the prior art, the seam machining method for laser etching of curved surfaces provided by this invention extracts multiple segmentation lines of the curved part model that has been graphicly segmented before laser etching. Based on the start point, end point and surface normal vector of each segmentation line, the motion trajectory of each segmentation line is determined. Under the vision system of the machine tool, the five-axis motion of the machine tool is performed according to the motion trajectory of each segmentation line. The motion trajectory of residual metal is determined in the motion trajectory of each segmentation line. The machining trajectory of the scanning galvanometer is generated based on the width of the residual metal. Under the laser etching system of the machine tool, the five-axis motion of the machine tool is performed according to the motion trajectory of the metal residue, and laser etching is performed simultaneously according to the machining trajectory of the scanning galvanometer to remove the residual metal and complete the seam machining of the curved part. Compared to existing technologies that achieve seam processing for laser etching of large-format parts on a plane by obtaining the splicing position of the current processing area and the next processing area, so that the next processing area is within the range of the current processing area, this invention determines the motion trajectory of each segmentation line by using the start point, end point, and surface normal vector of each segmentation line. This trajectory is in contact with the surface of the curved part. Among the motion trajectories of each segmentation line in contact with the surface of the curved part, the motion trajectory where residual metal exists is also in contact with the surface of the curved part. Laser etching is performed by using the motion trajectory in contact with the surface, which can remove residual metal from the curved part in contact with the surface. This invention is well applicable to the seam processing of laser etching of large-format curved surfaces. Attached Figure Description

[0046] The above and other objects, features, and advantages of exemplary embodiments of the present invention will become readily apparent upon reading the following detailed description with reference to the accompanying drawings. In the drawings, several embodiments of the invention are illustrated by way of example and not limitation, with the same or corresponding reference numerals denoteing the same or corresponding parts, wherein:

[0047] Figure 1 The flowchart of a seam fabrication method suitable for laser etching of curved surfaces is illustrated schematically. Figure 1 ;

[0048] Figure 2 The flowchart of a seam fabrication method suitable for laser etching of curved surfaces is illustrated schematically. Figure 2 . Detailed Implementation

[0049] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0050] It should be noted that, unless otherwise stated, the technical or scientific terms used in this invention should have the ordinary meaning as understood by one of ordinary skill in the art.

[0051] In existing technologies, the seam fabrication for laser etching is typically achieved by determining the splicing position between the current and next processing areas, ensuring that the next processing area falls within the range of the current processing area. However, this invention addresses the fact that existing laser etching seam fabrication methods only address the splicing of large-area laser-etched parts on planar surfaces, and are not suitable for the splicing of large-area curved laser-etched parts. Therefore, a method applicable to the splicing of large-area curved laser-etched parts is needed to replace the existing method which is only suitable for large-area laser-etched parts on planar surfaces. This invention obtains a curved surface part model that has undergone laser etching, extracts multiple segmentation lines from the curved surface part model that has been graphically segmented before laser etching, and determines the motion trajectory of each segmentation line based on its start point, end point, and surface normal vector. Under the vision system of the machine tool, the machine tool performs five-axis motion according to the motion trajectory of each segmentation line, and identifies the motion trajectory of residual metal within the motion trajectory of each segmentation line. The width of the residual metal is used to generate the processing trajectory of the scanning galvanometer. Under the laser etching system of the machine tool, the machine tool performs five-axis motion according to the motion trajectory of the metal residue, and simultaneously performs laser etching according to the processing trajectory of the scanning galvanometer to remove the residual metal and complete the seam processing of the curved surface part. This invention determines the motion trajectory of the seam of a curved part based on the start and end points of each segmentation line and the surface normal vector of the curved part model. Within this motion trajectory, a motion trajectory suitable for the presence of residual metal on the curved part is identified. The machine tool performs five-axis motion according to this motion trajectory, while simultaneously performing laser etching according to the processing trajectory of the scanning galvanometer to remove the residual metal and complete the seam processing of the curved part. The determined motion trajectory for the presence of residual metal is conformed to the curved surface of the part. Laser etching is performed through this motion, conforming to the curved surface of the part, to remove the residual metal. This method effectively removes residual metal from curved parts and is well-suited for seam processing of ultra-wide curved surfaces using laser etching.

[0052] The main idea of ​​this invention is to determine the motion trajectory of each segment line applicable to the curved part based on the starting point, ending point and surface normal vector of each segment line of the curved part model. Among the motion trajectories of each segment line, the motion trajectory of the curved part with residual metal can be determined. The machine tool can perform five-axis motion according to the motion trajectory of the metal residue applicable to the curved part, and at the same time, laser etching can be performed according to the processing trajectory of the scanning galvanometer to remove the residual metal of the curved part and complete the seam processing of the curved part.

[0053] The methods described in the embodiments of the present invention will be explained in detail below.

[0054] Figure 1 The flowchart of a seam processing method for laser etching of curved surfaces, as illustrated in an embodiment of the present invention, is shown schematically. Figure 1 See Figure 1 As shown, the method may include:

[0055] S101. Obtain the model of the curved surface part that has been laser-etched.

[0056] Among them, the curved part model is a model that has been graphic segmented before laser etching is completed, and the curved part model includes multiple segmentation lines.

[0057] This invention is realized by a processing device consisting of a vision system, a five-axis linkage machine tool, and a laser etching system.

[0058] The curved part model is an oversized curved part model. In the overall machining of oversized curved parts, the oversized graphic is divided into multiple graphics, which are then machined separately. For separate machining, the optical (laser etching) system needs to be moved to a designated position using machine tool motion before each graphic is machined. The movement of the laser etching system is affected by the machine tool's accuracy, resulting in deviations in the position of the movement. This causes deviations in the actual machined graphics within the laser etching area, leading to "seams" and "over-seams" between the divided graphics. Over-seammed graphics can be used normally, but the "seam" graphics are considered incompletely etched, leaving metal residue in the laser-etched area. This can cause circuit connections between the remaining metal layers, damaging the part's microstructure. Therefore, the seams in the curved laser etching need to be machined. Before machining the seams in the curved laser etching, a model of the laser-etched curved part needs to be obtained. The laser-etched curved part model has multiple seams, i.e., metal residue.

[0059] Since the surface of the un-etched curved part model exceeds the processing area of ​​the galvanometer, the entire curved part cannot be processed in one etching. Therefore, the curved graphic will be divided into multiple graphics based on the processing area and depth of focus of the galvanometer. The curved part model will contain multiple dividing lines. Then, laser etching will be performed on each of the divided graphics. The curved part model includes multiple dividing lines.

[0060] S102. Extract multiple dividing lines and determine the motion trajectory of each dividing line based on its starting point, ending point, and surface normal vector.

[0061] Extract multiple dividing lines from the surface part model that has undergone graphic segmentation. Since each dividing line has two endpoints, one endpoint can be used as the starting point and the other endpoint as the ending point. Based on the starting point, ending point and surface normal vector of each dividing line, determine the motion trajectory of each dividing line.

[0062] S103. Under the vision system of the machine tool, perform five-axis motion of the machine tool according to the motion trajectory of each dividing line, and determine the motion trajectory of the residual metal in the motion trajectory of each dividing line, and generate the processing trajectory of the scanning galvanometer based on the width of the residual metal.

[0063] In the state of the machine tool's vision system, or in other words, using the five-axis conversion parameters of the vision system of a five-axis five-linkage machine tool, the machine tool performs five-axis motion according to the motion trajectory of each dividing line. At the same time, the vision system observes the motion trajectory of each dividing line to see if there is any residual metal. It determines the motion trajectory where there is residual metal (i.e., seam) and generates the processing trajectory of the scanning galvanometer based on the width of the residual metal (i.e., seam).

[0064] S104. Under the laser etching system of the machine tool, the machine tool performs five-axis motion according to the motion trajectory of the metal residue, and simultaneously performs laser etching according to the processing trajectory of the scanning galvanometer to remove the residual metal and complete the seam processing of the curved part.

[0065] In the state of the laser etching system of the machine tool, or in other words, using the five-axis conversion parameters of the laser etching system of a five-axis five-linkage machine tool, the machine tool performs five-axis motion according to the motion trajectory of the metal residue, and at the same time performs laser etching according to the processing trajectory of the scanning galvanometer, so as to remove the residual metal and complete the seam processing of the curved part.

[0066] Laser etching is performed according to the processing trajectory of the scanning galvanometer. The scanning galvanometer moves linearly along the width of the residual metal. During the movement, the laser etching system of the five-axis five-linkage machine tool removes the residual metal by laser etching, completing the seam processing of curved parts.

[0067] Based on the above Figure 1 As can be seen from the implementation method, when processing the seams suitable for curved surface laser etching, the embodiments of the present invention extract multiple dividing lines of the curved surface part model that has been graphicly segmented before laser etching is completed, and determine the motion trajectory of each dividing line according to the starting point, ending point and surface normal vector of each dividing line. Under the vision system of the machine tool, the machine tool performs five-axis motion according to the motion trajectory of each dividing line, and determines the motion trajectory of residual metal in the motion trajectory of each dividing line. The processing trajectory of the scanning galvanometer is generated based on the width of the residual metal. Under the laser etching system of the machine tool, the machine tool performs five-axis motion according to the motion trajectory of the metal residue, and simultaneously performs laser etching according to the processing trajectory of the scanning galvanometer to remove the residual metal and complete the seam processing of the curved surface part. In this way, the motion trajectory of each segmentation line, determined by the starting point, ending point, and surface normal vector of each segmentation line, is in contact with the surface of the curved part. Among the motion trajectories of each segmentation line in contact with the surface of the curved part, the motion trajectory where residual metal exists is also in contact with the surface of the curved part. Laser etching is performed by using the motion trajectory in contact with the surface, which can remove residual metal from the curved part in contact with the surface. This method is well applicable to the seam processing of laser etching on ultra-wide curved surfaces.

[0068] As a refinement and extension of the above embodiments, it can be achieved through... Figure 2 The specific operation for seam processing applicable to laser etching of curved surfaces is illustrated. Figure 2 This is a flowchart of a seam processing method for curved surface laser etching according to an embodiment of the present invention. Figure 2 See Figure 2 As shown, an embodiment of the present invention provides a seam processing method suitable for curved surface laser etching, which may include:

[0069] S201. Based on the galvanometer processing area and focal depth, the model of the curved surface part to be etched is graphically segmented, and the center point and surface normal vector of each segmented region are calculated.

[0070] Specifically, the model of the etched curved surface part is divided into multiple segmented regions based on the processing area and focal depth of the galvanometer; multiple triangular facets belonging to each segmented region are found, and the outer edges of the triangular facets are determined, which are the boundaries of the segmented regions; the coordinates of the center point of the segmented region are calculated based on the boundaries, and the triangular facet containing the center point is searched based on the center point coordinates, and the normal vector of the triangular facet is used as the surface normal vector of the segmented region.

[0071] S202. Determine the processing trajectory of the scanning galvanometer in each segmented region.

[0072] Specifically, the machine tool's AC axis rotates around the X and Z axes respectively. The corresponding rotation matrix is ​​obtained based on the rotation amount. The coordinate system of the rotating galvanometer is calculated using the rotation matrix. The coordinates of each point of the graphic to be processed are obtained in the rotating galvanometer coordinate system. The surface graphic after coordinate transformation is obtained using the coordinates of each point on the graphic to be processed. The center point of the segmented area and the surface normal vector are taken as the origin, and the vector direction is the Z direction of the projection coordinate system. The XY direction of the scanning galvanometer coordinate system of the current processing area is taken as the XY direction of the projection coordinate system. The surface graphic is projected into a planar graphic according to this projection direction. The resulting planar graphic is the scanning trajectory of the laser galvanometer.

[0073] S203. Using the center point and the surface normal vector as the target point position of the machine tool's five-axis motion, and using the machining trajectory as the machining graphic of each segmented area for scanning and machining, the laser etching machining of the curved surface part is completed.

[0074] The laser beam emitted by the laser to be used is transmitted through the optical path system. It is reflected by the X and Y axis laser plane mirrors in the laser galvanometer and converged by the scanning focusing lens. The laser beam is then moved to the center point of the part using a five-axis five-linkage machine tool to perform scanning trajectory processing with the surface normal vector, thus completing the laser etching processing of the curved part.

[0075] S204. Obtain the model of the curved surface part that has been laser-etched.

[0076] Among them, the curved part model is a model that has been graphic segmented before laser etching is completed, and the curved part model includes multiple segmentation lines.

[0077] Step S204 is the same as step S101, so it will not be described again here.

[0078] S205, Extract multiple dividing lines.

[0079] Each dividing line includes a first endpoint and a second endpoint.

[0080] After dividing the model of the curved part to be etched into a graphic based on the processing area and depth of focus of the galvanometer, the model of the curved part includes multiple dividing lines, which can be directly extracted. Each dividing line has two endpoints, and any one endpoint can be called the first endpoint and the other endpoint is the second endpoint.

[0081] Before extracting multiple dividing lines, the method also includes:

[0082] Step A1: Identify the starting point coordinates and ending point coordinates for each of the multiple dividing lines.

[0083] Step A2: Among multiple dividing lines, filter out multiple dividing lines that have the same starting point coordinates and the same ending point coordinates.

[0084] Identify dividing lines with the same start and end points, and group them into groups. Grouping dividing lines with the same start and end points into groups facilitates the deduplication of subsequent dividing lines.

[0085] Step A3: Remove duplicates from the selected dividing lines.

[0086] The selected dividing lines are deduplicated, and only one dividing line with the same starting point and ending point is retained to ensure that the movement trajectories of subsequent dividing lines will not be repeated.

[0087] S206. Take the first endpoint of each dividing line as the starting point of the movement and the second endpoint of each dividing line as the ending point of the movement.

[0088] The starting point of the movement is taken as any one of the endpoints of each dividing line, i.e., the first endpoint, and the ending point of the movement is taken as the other endpoint of each dividing line, i.e., the second endpoint.

[0089] S207. Using the direction of the surface normal vector perpendicular to the surface where each dividing line is located as the direction of motion, the motion trajectory from the starting point to the end point of each dividing line according to the direction of motion is determined as the motion trajectory of each dividing line.

[0090] The motion trajectory of each dividing line is determined according to the coordinate system of the curved part model. During the motion, the direction of the surface normal vector is perpendicular to the surface direction of the curved part, and the direction of the surface normal vector points from the inside of the curved part to the outside.

[0091] S208. Under the vision system of the machine tool, perform five-axis motion of the machine tool according to the motion trajectory of each dividing line, and determine the gray value of the motion trajectory of each dividing line in the motion trajectory of each dividing line.

[0092] Since the gray values ​​of the motion trajectories of the dividing lines with residual metal are different from those of the motion trajectories of the dividing lines without residual metal, there is a gray value difference in visual perception. It is necessary to determine the motion trajectory with residual metal by using the gray value difference. Therefore, it is necessary to determine the gray value of the motion trajectory of each dividing line.

[0093] S209. Compare the gray values ​​of the motion trajectories of each dividing line with the preset gray values ​​to determine the motion trajectories that are different from the preset gray values, and determine the motion trajectories that are different from the preset gray values ​​as motion trajectories containing residual metal.

[0094] The grayscale value of the motion trajectory of the dividing line without residual metal can be determined as the preset grayscale value. The grayscale value of the motion trajectory of each dividing line is compared with the preset grayscale value, i.e., the grayscale value of the motion trajectory of the dividing line without residual metal, to determine the motion trajectory that is different from the preset grayscale value, and the motion trajectory that is different from the preset grayscale value is determined as the motion trajectory with residual metal.

[0095] After comparing the grayscale values ​​of the motion trajectories of each segmentation line with preset grayscale values ​​to identify motion trajectories that differ from the preset grayscale values, and determining these motion trajectories as containing residual metal, the method further includes:

[0096] Step B1: Determine the preset start point and preset end point of the trajectory where residual metal exists;

[0097] Step B2: Mark the preset start point and preset end point to obtain the marked preset start point and marked preset end point.

[0098] The scanning galvanometer is controlled to move by marking a preset starting point, and to stop moving by marking a preset ending point.

[0099] S210, Generate the machining trajectory of the scanning galvanometer based on the width of the residual metal.

[0100] The machining trajectory of the scanning galvanometer is generated based on the width of the residual metal, including:

[0101] Step C1: Determine the ratio of the pixel blocks in the image of the curved part model acquired by the vision system to the actual size of the curved part.

[0102] The vision system establishes a proportional relationship between the pixel blocks of the curved part model image and the actual size of the curved part, after being calibrated with a standard ruler.

[0103] Step C2: Acquire an image of the motion trajectory containing residual metal, and identify the pixel blocks of residual metal in the image.

[0104] Step C3: Calculate the width of the residual metal based on the pixel blocks and ratios of the residual metal in the image, and generate the processing trajectory of the scanning galvanometer based on the width of the residual metal.

[0105] The width of the residual metal is calculated, and the processing trajectory of the scanning galvanometer is generated based on the width of the residual metal, which can determine the trajectory of the laser galvanometer for laser etching.

[0106] S211. Under the condition of the laser etching system of the machine tool, the five-axis motion of the machine tool is performed according to the motion trajectory of the metal residue, and laser etching is performed simultaneously according to the processing trajectory of the scanning galvanometer to remove the residual metal and complete the seam processing of the curved part.

[0107] In the laser etching system of the machine tool, the machine tool performs five-axis motion according to the motion trajectory of the metal residue, and simultaneously performs laser etching according to the machining trajectory of the scanning galvanometer to remove the residual metal and complete the seam machining of the curved surface parts, including:

[0108] Step D1: With the laser etching system of the machine tool in operation, control the scanning galvanometer to move to the preset starting point of the mark.

[0109] Step D2: Control the center point of the laser galvanometer etching area on the surface of the curved part, and perform five-axis machine tool motion along the motion trajectory of the metal residue.

[0110] Step D3: Simultaneously control the laser galvanometer to perform laser etching by scanning the processing trajectory of the galvanometer, so as to remove the residual metal in the movement trajectory where there is residual metal.

[0111] Step D4: When the scanning galvanometer is detected to have moved to the preset endpoint marked, control the scanning galvanometer to stop moving and control the laser galvanometer to stop laser etching.

[0112] Step D5: Control the scanning galvanometer to move to the preset starting point marked by the next motion trajectory with residual metal, and repeat steps D1 to D4 until all residual metal in the motion trajectory with residual metal is removed to complete the seam processing of the curved part.

[0113] When the scanning galvanometer is detected to have moved to the marked preset endpoint, the scanning galvanometer is controlled to stop moving and the laser galvanometer is controlled to stop laser etching. The process also includes: determining whether there is a movement trajectory of residual metal; if so, the scanning galvanometer is controlled to move to the preset starting point marked by the next movement trajectory of residual metal; if not, the scanning galvanometer is not controlled to move, and the seam processing of the curved part is completed.

[0114] This invention provides a solution to the inevitable seam phenomenon caused by the limited precision of machine tools. It can repair the seams that occur during graphic segmentation and etching, and achieve complete processing of electrical performance parts such as radomes and conformal antennas, avoiding the phenomenon of functional failure of processed parts due to insufficient machining precision of machine tools.

[0115] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for machining seams in laser etching of curved surfaces, characterized in that, The method includes: Obtain a curved surface part model that has been laser etched. The curved surface part model is a model that has been graphic segmented before laser etching is completed. The curved surface part model includes multiple segmentation lines. Extract the multiple segmentation lines, and determine the motion trajectory of each segmentation line based on its starting point, ending point, and surface normal vector; Under the vision system of the machine tool, the five-axis motion of the machine tool is performed according to the motion trajectory of each dividing line, and the motion trajectory with residual metal is determined in the motion trajectory of each dividing line, and the processing trajectory of the scanning galvanometer is generated based on the width of the residual metal. In the state of the laser etching system of the machine tool, the five-axis motion of the machine tool is performed according to the motion trajectory of the residual metal, and laser etching is performed simultaneously according to the processing trajectory of the scanning galvanometer to remove the residual metal and complete the seam processing of the curved part. The step of extracting the multiple segmentation lines and determining the motion trajectory of each segmentation line based on its start point, end point, and surface normal vector includes: Extract the plurality of dividing lines, each dividing line including a first endpoint and a second endpoint; The first endpoint of each dividing line is taken as the starting point of the movement, and the second endpoint of each dividing line is taken as the ending point of the movement. Using the direction of the surface normal vector perpendicular to the surface where each dividing line is located as the direction of motion, the motion trajectory along the starting point to the ending point of each dividing line according to the direction of motion is determined as the motion trajectory of each dividing line. In the state of the machine tool's vision system, the machine tool performs five-axis motion according to the motion trajectory of each dividing line, and determines the motion trajectory containing residual metal in the motion trajectory of each dividing line. The processing trajectory of the scanning galvanometer is generated based on the width of the residual metal, including: Under the vision system of the machine tool, the five-axis motion of the machine tool is performed according to the motion trajectory of each segmentation line, and the gray value of the motion trajectory of each segmentation line is determined in the motion trajectory of each segmentation line. The gray values ​​of the motion trajectories of each dividing line are compared with preset gray values ​​to determine motion trajectories that are different from the preset gray values, and the motion trajectories that are different from the preset gray values ​​are determined to be motion trajectories containing residual metal. The machining trajectory of the scanning galvanometer is generated based on the width of the residual metal.

2. The method according to claim 1, characterized in that, Before extracting the plurality of dividing lines, the method further includes: The starting point coordinates and ending point coordinates of the multiple dividing lines are identified respectively; Among multiple dividing lines, filter out those that have the same starting coordinates and the same ending coordinates; Remove duplicates from the selected dividing lines.

3. The method according to claim 1, characterized in that, The process of generating the scanning galvanometer trajectory based on the width of the residual metal includes: Determine the ratio of the pixel blocks in the image of the curved part model acquired by the vision system to the actual size of the curved part; Acquire images of the motion trajectory containing residual metal, and identify the pixel blocks of residual metal in the images; Based on the pixel blocks of residual metal in the image and the ratio, the width of the residual metal is calculated, and the processing trajectory of the scanning galvanometer is generated using the width of the residual metal.

4. The method according to claim 1, characterized in that, After comparing the grayscale values ​​of the motion trajectories of each segmentation line with preset grayscale values ​​to determine motion trajectories that differ from the preset grayscale values, and identifying these motion trajectories as containing residual metal, the method further includes: Determine the preset start and preset end points of the trajectory where residual metal exists; The preset starting point and the preset ending point are marked to obtain the marked preset starting point and the marked preset ending point.

5. The method according to claim 4, characterized in that, In the state of the laser etching system of the machine tool, the machine tool performs five-axis motion according to the motion trajectory of the residual metal, and simultaneously performs laser etching according to the processing trajectory of the scanning galvanometer to remove the residual metal and complete the seam processing of the curved surface part, including: In the state of the laser etching system of the machine tool, control the scanning galvanometer to move to the preset starting point of the mark; The center point of the laser galvanometer etching area is controlled to be on the surface of the curved part, and the machine tool performs five-axis motion along the motion trajectory of the residual metal. Simultaneously, the laser galvanometer is controlled to perform laser etching along the processing trajectory of the scanning galvanometer to remove residual metal from the movement trajectory where residual metal currently exists. When the scanning galvanometer is detected to have moved to the preset endpoint of the mark, the scanning galvanometer is controlled to stop moving and the laser galvanometer is controlled to stop laser etching. The scanning galvanometer is controlled to move to the preset starting point marked by the next motion trajectory containing residual metal, until all residual metal in the motion trajectory containing residual metal is removed, so as to complete the seam processing of the curved part.

6. The method according to claim 5, characterized in that, After controlling the scanning galvanometer to stop moving and the laser galvanometer to stop laser etching when the scanning galvanometer is detected to have moved to the preset endpoint of the mark, the method further includes: Determine if there is a movement trajectory of residual metal; If so, control the scanning galvanometer to move to the preset starting point marked by the next motion trajectory where residual metal exists; If not, the movement of the scanning galvanometer is not controlled, and the seam processing of the curved parts is completed.

7. The method according to claim 1, characterized in that, The direction of the surface normal vector is perpendicular to the surface direction of the surface part, and the direction of the surface normal vector points from the inside of the surface part to the outside.

8. The method according to claim 1, characterized in that, Before obtaining a model of the laser-etched curved surface part, the method further includes: Based on the galvanometer processing area and focal depth, the model of the curved surface part to be etched is graphically segmented, and the center point and surface normal vector of each segmented region are calculated. Determine the processing trajectory of the scanning galvanometer in each segmented region; The center point and the surface normal vector are used as the target point positions for the five-axis motion of the machine tool, and the machining trajectory is used as the machining pattern for each segmented area for scanning and machining to complete the laser etching of the curved part.

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