Ejector Pin Positioning Method, Electronic Device, and Storage Medium in Laser Processing

Abstract

The present application provides a thimble positioning method, an electronic device and a storage medium during laser processing, belonging to the technical field of laser beam processing. The method includes: when it is detected that a to-be-processed plate is placed in a machine tool, acquiring a captured image of the to-be-processed plate and a processing drawing, where the captured image includes visual information of the to-be-processed plate, and the processing drawing includes processing pattern information of the to-be-processed plate; based on the visual information of the to-be-processed plate and the processing pattern information of the to-be-processed plate, determining the rotational offset amount and the preset thimble points of the to-be-processed plate; based on the rotational offset amount and the preset thimble points, determining the thimble installation points of the to-be-processed plate relative to the machine tool; controlling the movable laser head of the machine tool to move according to the thimble installation points to guide the positioning and installation of the thimble. The present application can effectively improve the efficiency and accuracy of thimble point determination.

Description

Technical Field

[0001] The present application relates to the technical field of laser beam processing, and particularly relates to a thimble positioning method, an electronic device, and a storage medium during laser processing. Background Art

[0002] In the process of modern industrial manufacturing, the laser processing of metal substrates is a complex and precise task. To meet the requirements of high-precision processes, a relatively large gas pressure is usually applied during the processing to ensure the processing quality. However, in this high-pressure environment, the jianshan (i.e., the component on the machine tool used to support or fix the metal substrate) under the metal substrate will come into contact with the surface of the metal substrate, resulting in scratches or even product scrapping. To solve this problem, thimbles are usually placed at specific positions on the metal substrate before processing to prevent the jianshan from directly contacting and scratching the material surface.

[0003] However, the existing placement of thimbles relies on the visual judgment and manual placement of workers. Moreover, since the metal substrate may have a slight angular deflection when placed on the processing platform of the machine tool by the worker and cannot completely coincide with the machine tool coordinate system, even if the worker places the thimbles at the predetermined thimble positions, the actual positions may deviate, thus increasing the risk of product scrapping.

[0004] Therefore, in the process of laser processing, there is currently a technical problem of low precision in the positioning and installation of thimbles. Summary of the Invention

[0005] The purpose of the present application is to provide a thimble positioning method, an electronic device, and a storage medium during laser processing to solve the above problems.

[0006] To achieve the above purpose, in the first aspect, the present application proposes a thimble positioning method during laser processing, and the method includes:

[0007] When it is detected that a to-be-processed plate is placed into the machine tool, obtain a captured image of the to-be-processed plate and a processing drawing, where the captured image includes the visual information of the to-be-processed plate, and the processing drawing includes the processing pattern information of the to-be-processed plate;

[0008] Based on the visual information of the to-be-processed plate and the processing pattern information of the to-be-processed plate, determine the rotational offset amount and the preset thimble positions of the to-be-processed plate;

[0009] Based on the rotational offset amount and the preset thimble positions, determine the thimble installation positions of the to-be-processed plate relative to the machine tool;

[0010] Control the movable laser head of the machine tool to move according to the thimble installation positions to guide the positioning and installation of the thimbles.

[0011] In some embodiments, determining the rotational offset and the preset position of the thimble of the to-be-processed sheet based on the visual information of the to-be-processed sheet and the processing pattern information of the to-be-processed sheet includes:

[0012] Based on the visual information of the to-be-processed sheet, obtaining first position information of the actual marking point of the to-be-processed sheet relative to the actual coordinate system;

[0013] Based on the processing pattern information of the to-be-processed sheet, obtaining second position information of the theoretical marking point of the to-be-processed sheet relative to the machine tool coordinate system;

[0014] Based on the first position information and the second position information, calculating a position offset matrix for transforming the theoretical marking point to the actual marking point;

[0015] Based on the position offset matrix, determining the rotational offset of the to-be-processed sheet in the machine tool coordinate system.

[0016] In some embodiments, before obtaining the first position information of the actual marking point of the to-be-processed sheet relative to the actual coordinate system, it further includes:

[0017] Calibrating the camera of the machine tool to determine the center distance between the movable laser head and the camera, and the ratio between each pixel point in the captured image and the actual physical unit;

[0018] Based on the center distance and the ratio, mapping the pixel coordinates of each pixel point in the captured image to the actual coordinate system.

[0019] In some embodiments, after obtaining the first position information of the actual marking point of the to-be-processed sheet relative to the actual coordinate system based on the visual information of the to-be-processed sheet, it further includes:

[0020] Controlling the movable laser head of the machine tool to move according to the first position information to collect real-time image information of the actual marking point;

[0021] Based on the real-time image information, framing a boundary region including the actual marking point;

[0022] Saving the boundary region as a positioning template.

[0023] In some embodiments, before saving the boundary region as a positioning template, it further includes:

[0024] Selecting a number of data points from the boundary region as test points;

[0025] Performing feature comparison between the test points and the actual marking point;

[0026] When the comparison result does not meet the preset comparison standard, adjust the boundary region.

[0027] In some embodiments, the determining the rotational offset and the preset thimble points of the to-be-machined sheet based on the visual information of the to-be-machined sheet and the machining drawing information of the to-be-machined sheet includes:

[0028] Determine a non-drawing region based on the machining drawing information of the to-be-machined sheet;

[0029] Determine a preset thimble region based on the distribution characteristics of the non-drawing region;

[0030] Obtain the dimension information and / or weight information of the to-be-machined sheet, and determine the preset number of thimbles based on the dimension information and / or weight information;

[0031] Determine the preset thimble points based on the preset thimble region and the preset number of thimbles.

[0032] In some embodiments, the captured image further includes the distribution information of the sword mountains of the machine tool, and the determining the preset thimble points based on the preset thimble region and the preset number of thimbles includes:

[0033] Extract the contour coordinates of the sword mountains based on the distribution information of the sword mountains;

[0034] Perform a difference set operation on the contour coordinates of the sword mountains and the preset thimble region to determine a thimble planning region;

[0035] Determine the preset thimble points based on the thimble planning region and the preset number of thimbles.

[0036] In some embodiments, the determining the thimble installation points of the to-be-machined sheet relative to the machine tool based on the rotational offset and the preset thimble points includes:

[0037] Calculate the rotational compensation amount and the displacement compensation amount of the preset thimble points based on the rotational offset;

[0038] Determine the thimble installation points corresponding to the preset thimble points in the machine tool coordinate system based on the rotational compensation amount and the displacement compensation amount.

[0039] In a second aspect, the present application proposes an electronic device, including:

[0040] One or more processors;

[0041] A memory for storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors are caused to execute the thimble positioning method in the laser processing process as described above.

[0042] In a third aspect, the present application proposes a storage medium storing executable instructions, which when executed by a processor cause the processor to execute the thimble positioning method in the laser processing process as described above.

[0043] Compared with the prior art, the beneficial effects of the present application include:

[0044] In the first aspect, by obtaining a captured image of the workpiece to be processed and a processing drawing when it is detected that the workpiece to be processed is placed in the machine tool, the problem of thimble positioning deviation caused by incomplete information or deviation in the placement position of the workpiece can be effectively reduced.

[0045] In the second aspect, based on the visual information and processing pattern information of the workpiece to be processed obtained, the rotational offset amount of the workpiece to be processed and the preset thimble points are determined. Compared with the traditional method that relies on manual marking of thimble points and visually judges by humans to place the thimble, the present application can accurately calculate the rotational offset amount of the workpiece relative to the machine tool coordinate system and automatically determine the preset thimble points according to the processing drawing. This improvement eliminates the uncertainty brought by human factors and does not require manual marking of thimble points, which can effectively improve the efficiency and accuracy of determining thimble points.

[0046] In the third aspect, the thimble installation points of the workpiece to be processed relative to the machine tool are determined based on the calculated rotational offset amount and preset thimble points. This means that even if there is an angular deflection during the placement of the workpiece, the present application can calculate and compensate to accurately install the thimble at the thimble installation points. This real-time adjustment and compensation mechanism can ensure that the thimble is always in the accurate installation position, avoiding direct contact between the sword and the surface of the workpiece to be processed, thereby preventing the generation of scratches. In the fourth aspect, by controlling the movable laser head of the machine tool to move according to the thimble installation points to guide the positioning and installation of the thimble, the accuracy and reliability of thimble positioning can be ensured, and the risk of product scrapping is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application and should not be regarded as limiting the scope of the present application.

[0048] Figure 1 It is a schematic flowchart of the thimble positioning method in the laser processing process in one embodiment;

[0049] Figure 2Schematic diagram of the machining pattern information of the machining drawing in the laser machining process in an embodiment;

[0050] Figure 3 Partial flowchart of the thimble positioning method in the laser machining process in an embodiment;

[0051] Figure 4 Refined flowchart of the thimble positioning method in the laser machining process in an embodiment;

[0052] Figure 5 Flowchart of the thimble positioning method in the laser machining process in another embodiment;

[0053] Figure 6 Flowchart of the thimble positioning method in the laser machining process in yet another embodiment;

[0054] Figure 7 Schematic diagram of the structure of the electronic device involved in the thimble positioning method in the laser machining process in the embodiment of the present application. Detailed implementation manners

[0055] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0056] All terms used in the present application (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification, and should not be interpreted in an idealized or overly rigid manner.

[0057] For example, terms such as "first" and "second" used in the present application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish the first element from another element. For example, without departing from the scope of the present application, the first position information may be referred to as the second position information, and similarly, the second position information may be referred to as the first position information. Both the first position information and the second position information are position information, but they are not the same position information.

[0058] For another example, terms such as "include" and "comprise" used in the present application indicate the presence of features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0059] As described above, the existing thimble placement relies on the visual judgment and manual placement of workers. Moreover, when the metal substrate is placed on the processing platform of the machine tool by the worker, there may be a slight angular deflection, making it impossible to perfectly match the machine tool coordinate system. This means that even if the worker places the thimble at the predetermined thimble points, the actual position may deviate, thus increasing the risk of product scrapping. Therefore, during the laser processing, there is currently a technical problem of low precision in thimble positioning and installation. For this reason, this application proposes a thimble positioning method, an electronic device, and a storage medium during the laser processing, which can effectively improve the efficiency and accuracy of thimble point determination.

[0060] As Figure 1 shown, a thimble positioning method during the laser processing proposed in an embodiment of this application includes the following steps:

[0061] Step S10, when it is detected that the to-be-processed sheet is placed into the machine tool, obtain a captured image of the to-be-processed sheet and a processing drawing, where the captured image includes visual information of the to-be-processed sheet, and the processing drawing includes processing pattern information of the to-be-processed sheet.

[0062] In this embodiment, the to-be-processed sheet refers to a metal or non-metal material sheet that needs to undergo various laser processing operations (such as laser cutting, laser marking, laser engraving, etc.) during industrial manufacturing. The machine tool is a mechanical device used for laser processing of the to-be-processed sheet. The machine tool realizes the laser processing operation of the to-be-processed sheet through the relative movement between the movable laser head and the to-be-processed sheet, so as to achieve the dimensions and shapes required by the processing drawing. The captured image is an image obtained by photographing the to-be-processed sheet placed in the machine tool using an image acquisition device (such as a camera). The visual information included therein refers to the physical characteristic information about the surface of the to-be-processed sheet, such as shape, texture, color, etc. The processing drawing is a technical document used to guide machining and manufacturing. It may detail one or more of the information such as the dimensions, shape, material requirements, surface treatment, tolerance range, and processing technology of the to-be-processed part or product. The processing pattern information refers to the pattern information related to the processing of the to-be-processed sheet included in the processing drawing, and may include one or more of the processing pattern, processing path, theoretical marking points, and thimble points.

[0063] As a feasible implementation manner of detecting that the to-be-processed sheet is placed into the machine tool, the control system of the machine tool is connected to an operation interface, and based on the operation interface, a trigger instruction for the to-be-processed sheet being placed in the machine tool is received. The trigger instruction can be an instruction triggered by a worker to confirm the placement state of the to-be-processed sheet through a button or a slider on the operation interface.

[0064] As another feasible implementation for detecting the placement of the workpiece plate to be processed into the machine tool, the placement state of the workpiece plate to be processed is detected by at least one sensor. For example, an optoelectronic sensor is used to detect whether the workpiece plate to be processed is placed into the machine tool by emitting and receiving light. When the workpiece plate to be processed is placed into the machine tool, the change in the blocked light or reflected light will be captured by the optoelectronic sensor. Another example is to detect the change in the pressure exerted on the machine tool by the workpiece plate to be processed through a pressure sensor. When the pressure increases to a stable value, it is determined that the workpiece plate to be processed has been placed into the machine tool.

[0065] Step S20: Based on the visual information of the workpiece plate to be processed and the processing drawing information of the workpiece plate to be processed, determine the rotational offset and the preset thimble position of the workpiece plate to be processed.

[0066] In this embodiment, the rotational offset refers to the offset information between the actual placement position and the standard position of the workpiece plate to be processed when it is placed on the machine tool in the machine tool coordinate system. The rotational offset includes one or more of the rotational angle and translation distance in the machine tool coordinate system. The preset thimble position refers to the position where the thimble is pre-set on the processing drawing according to the processing drawing information. Among them, the preset thimble position can be marked by the operator on the processing drawing in advance, or can be automatically preset by the control system of the machine tool on the processing drawing according to the processing drawing information. Figure 2 The pentagram mark pointed by the arrow in the figure is the preset thimble position.

[0067] In some embodiments, such as Figure 3 shown, step S20 includes:

[0068] Step A10: Based on the visual information of the workpiece plate to be processed, obtain the first position information of the actual marked points of the workpiece plate to be processed relative to the actual coordinate system.

[0069] In this embodiment, the marked points (Mark points) are reference points for positioning and alignment, including actual marked points and theoretical marked points. Among them, the actual marked points are physical reference points pre-marked on the entity of the workpiece plate to be processed, which can be specific patterns, holes or other obvious features on the workpiece plate to be processed. The actual coordinate system is a coordinate system established based on the captured image, which reflects the coordinate positions of each pixel point in the captured image.

[0070] Use image recognition algorithms (such as template matching, feature extraction, etc.) to identify the actual marked points from the visual information of the workpiece plate to be processed, save the position information of each actual marked point in the actual coordinate system, and form a set containing multiple point coordinates.

[0071] In some embodiments, the camera of the machine tool can be calibrated to determine the center distance between the movable laser head and the camera (i.e., the physical distance between the movable laser head and the optical center of the camera), and the ratio between each pixel point in the captured image and the actual physical unit. Furthermore, based on the center distance and the ratio, the pixel coordinates of each pixel point in the captured image are mapped to the actual coordinate system, so as to determine the position information of the actual marking points shown in the captured image in the actual coordinate system.

[0072] As a feasible embodiment of camera calibration, the cross calibration method can be adopted to calibrate the camera. Specifically, a pre-drawn theoretical cross icon is obtained, and the length and shape of the theoretical cross icon are known, which is convenient for subsequent calibration calculations. According to the theoretical cross icon, the movable laser head of the machine tool is controlled to cut out an actual cross pattern on the plate to be processed as a reference for calibration. The camera of the machine tool is controlled to move to the upper position of the actual cross pattern and ensure that the actual cross pattern is within the field of view of the camera. The image area containing the actual cross pattern is selected as a sample image. The cross feature points (such as the intersection point) in the sample image are extracted through an image processing algorithm (such as edge detection) for subsequent calibration calculations. According to the cross feature points, the camera of the machine tool is controlled to move to four different positions (such as up, down, left, and right) of the actual cross in sequence, and images are collected respectively. At each position, the pixel coordinates of the cross feature points are extracted through image processing. According to the actual physical size of the actual cross and the pixel size in the sample image, the ratio of pixels to the actual physical unit (K value) is calculated. And through geometric relationships, the center distance between the movable laser head and the optical center of the camera is calculated.

[0073] It should be noted that in addition to cross calibration, methods such as checkerboard calibration and circular calibration plates can also be used to calibrate the camera, and the specific calibration method of the camera is not limited in this embodiment.

[0074] Furthermore, the pixel coordinates (X pixel, Y pixel) of the actual marking point (Mark point) in the captured image are identified through an image processing algorithm (such as template matching or feature extraction). The pixel coordinates are multiplied by the K value to be converted into physical coordinates (X physical, Y physical) relative to the actual coordinate system:

[0075] X physical = X pixel × K, Y physical = Y pixel × K.

[0076] For example, if the K value is 0.02 mm / pixel and the pixel coordinates of a certain actual marking point are (500, 300), then the physical coordinates (X physical, Y physical) are: X physical = 500 × 0.02 = 10, Y physical = 300 × 0.02 = 6 (the unit is mm).

[0077] The above physical coordinates do not take into account the offset between the movable laser head and the camera. If there is a center distance offset (ΔX, ΔY) between the movable laser head and the camera, the actual marking point can be represented according to the actual coordinates (Xactual, Yactual) with respect to the first position information in the actual coordinate system, where Xactual = Xphysical + ΔX and Yactual = Yphysical + ΔY. That is, Xactual = Xpixel × K + ΔX and Yactual = Ypixel × K + ΔY.

[0078] Step A20: Based on the machining drawing information of the to-be-machined plate, obtain the second position information of the theoretical marking point of the to-be-machined plate with respect to the machine tool coordinate system.

[0079] In this embodiment, the theoretical marking point is a theoretical reference point pre-marked on the machining drawing, which can be a specific pattern, such as Figure 2 the small hexagonal pattern marked with 1, 2, and 3. The machine tool coordinate system is the working space coordinate system of the machine tool itself, and all physical movements and operations of the machine tool are performed in this coordinate system.

[0080] In some embodiments, the machining drawing and the machine tool coordinate system can be aligned first. The alignment operation includes origin alignment, scale alignment, and direction alignment. After detecting that the machining drawing and the machine tool coordinate system are aligned, use an image recognition algorithm (such as template matching, feature extraction, etc.) to determine the theoretical marking point on the aligned machining drawing according to the machining drawing information, and determine the second position information of the theoretical marking point in the machine tool coordinate system.

[0081] Step A30: Based on the first position information and the second position information, calculate the position offset matrix for transforming the theoretical marking point to the actual marking point.

[0082] In some embodiments, the actual marking point (obtained in step A10) and the theoretical marking point (obtained in step A20) are put in one-to-one correspondence in sequence to ensure the consistency of quantity and position logic. Further, the position offset matrix from the theoretical marking point to the actual marking point is fitted by the least squares method. The position offset matrix includes rotation, translation, and scaling parameters, and the formula is as follows:

[0083]

[0084] where a, b, d, and e represent rotation and scaling, and c and f represent translation.

[0085] Step A40: Based on the position offset matrix, determine the rotational offset of the to-be-machined plate in the machine tool coordinate system.

[0086] In this embodiment, the rotational offset includes the rotation angle and translation distance of the workpiece to be machined relative to the machine tool coordinate system. By extracting the rotation parameters and translation parameters in the position offset matrix, the rotational offset of the workpiece to be machined can be obtained.

[0087] In some embodiments, as Figure 4 shown, after step A10, the following steps are further included:

[0088] Step A11, controlling the movable laser head of the machine tool to move according to the first position information, so as to collect the real-time image information of the actual marking point.

[0089] In this embodiment, the movable laser head is a moving component in the machine tool for performing laser processing (such as cutting, marking), and can drive the camera to move synchronously. According to the first position information of the actual marking point in the actual coordinate system obtained in step A10, such as the coordinates (X actual, Y actual), control the movable laser head of the machine tool to drive the camera to move to the position corresponding to the actual marking point. This step may involve converting the first position information from the actual coordinate system to the machine tool coordinate system, so as to control the movable laser head to move to the position corresponding to the actual marking point in the machine tool coordinate system. The specific coordinate conversion process is not described in detail in this embodiment, and reference can be made to steps S30 and S40 for the determination and guidance of the thimble installation position.

[0090] Step A12, based on the real-time image information, frame the boundary region including the actual marking point.

[0091] In this embodiment, the boundary region refers to a rectangular or polygonal region in the real-time image information that encloses the actual marking point and is used to define the positioning template matching range. The real-time image information containing the actual marking point is collected by the camera, and then the actual marking point in the real-time image information is identified by using image recognition algorithms (such as edge detection, boundary extraction, etc.), and the boundary region including the actual marking point is framed. As a feasible implementation manner of framing the boundary region, the actual marking point can be automatically located and the minimum circumscribed boundary region can be generated through connected component analysis.

[0092] Step A13, saving the boundary region as a positioning template.

[0093] In this embodiment, the positioning template can be used to more quickly obtain the actual marking points of each workpiece to be machined during the subsequent batch machining process of the workpieces to be machined.

[0094] In some embodiments, in order to verify and adjust the accuracy of the boundary region and ensure its consistency with the actual marking points, before step A13, several data points can be selected from within the boundary region as test points; the test points are compared with the actual marking points in terms of features; when the comparison result does not meet the preset comparison standard, the boundary region is adjusted. Finally, the adjusted boundary region that meets the preset comparison standard is saved as a positioning template.

[0095] Specifically, several pixel points (such as 10 to 20 points) can be randomly selected within the boundary region as test points. Key features are extracted from the test points and the actual marking points, and the key features can include at least one of geometric features (such as shape, edge curvature, area, etc.), texture features (such as gray-scale distribution, local binary pattern (LBP), etc.), and depth features (high-dimensional feature vectors extracted by a convolutional neural network (CNN)). Based on image processing or machine learning algorithms (such as template matching, feature point detection, deep learning models, etc.), the key features of the test points and the actual marking points are compared. A comparison result is generated according to the similarity of the comparison between the test points and the actual marking points, and the comparison result is compared with the preset comparison standard to determine whether the boundary region needs to be adjusted. For example, if more than 90% or less than 80% of the test points meet the comparison standard, it is determined that the boundary region needs to be adjusted; otherwise, it is determined that the boundary region is valid. When the comparison result does not meet the preset comparison standard, the specific parts that need to be adjusted (such as position offset, size change, etc.) are determined by analyzing the deviation in the comparison result. The boundary region is adjusted by means of moving, scaling, rotating, etc. until the comparison result meets the preset comparison standard. It can be understood that if one adjustment fails to reach the standard, the above steps can be repeated multiple times to gradually optimize the boundary region. The finally adjusted boundary region is saved as a positioning template to be used for positioning and alignment in subsequent processing to ensure the accuracy and efficiency of each processing.

[0096] Step S30: Based on the rotation offset and the preset position of the ejector pin, determine the installation position of the ejector pin of the to-be-processed plate relative to the machine tool.

[0097] In this embodiment, the installation position of the ejector pin refers to the set of three-dimensional space coordinates after coordinate transformation compensation, which is used to determine the physical installation position of the ejector pin. After performing a rotation offset transformation on the preset position of the ejector pin on the processing drawing based on the rotation offset, the installation position of the ejector pin is obtained to eliminate the placement error of the to-be-processed plate.

[0098] In some embodiments, based on the rotation offset, the rotation compensation amount and the displacement compensation amount of the preset position of the thimble can be calculated; based on the rotation compensation amount and the displacement compensation amount, the thimble installation position corresponding to the preset position of the thimble in the machine tool coordinate system can be determined. The thimble installation position can be represented by coordinates (X installation, Y installation).

[0099] Specifically, the rotation offset includes the rotation angle θ caused by the placement deviation of the plate and the translation deviation ( , ). The set of preset positions of the thimble defined in the processing drawing is {(X1, Y1), (X2, Y2),..., (Xn, Yn)}. The rotation compensation amount is the angle θ that needs to be rotated in the reverse direction to offset the angular deflection of the plate to be processed. The displacement compensation amount is the offset and that needs to be translated in the reverse direction to offset the translation deviation of the plate to be processed. Through the inverse transformation of rotation and translation, the preset position of the thimble is converted from the plate coordinate system to the machine tool coordinate system, then X installation = X theory × cosθ + Y theory × sinθ , Y installation = X theory × sinθ + Y theory × cosθ .

[0100] Exemplarily, assume that the preset position of the thimble of an aluminum substrate is (100, 50), the detected translation offset of the aluminum substrate is ΔX = 2, ΔY = 1, and the rotation offset θ = 5°. Based on the above formula, X installation = 101.98 mm can be calculated. Y installation = 42.09 mm. Therefore, the actual installation position of the thimble is (101.98, 42.09) mm.

[0101] Step S40, control the movable laser head of the machine tool to move according to the thimble installation position to guide the positioning and installation of the thimble.

[0102] Convert the thimble installation position into a control instruction executable by the machine tool (which can be G-code, the standard programming language of a numerical control machine tool, used to control parameters such as motion axes, rotational speed, and feed), and control the movable laser head of the machine tool to move successively according to the thimble installation position to guide the worker to place the thimble. In some embodiments, a cross or circular light spot can be projected at the thimble installation position through a low-power laser to indicate the thimble placement position.

[0103] In some embodiments, after the thimble is placed, the actual installation position of the thimble can also be verified by secondary shooting with a camera to check whether there is a deviation from the thimble installation position. When the deviation exceeds the allowable range, an alarm prompt can be triggered to re-place or automatically compensate the subsequent positions.

[0104] In the thimble positioning method during the laser processing proposed in the embodiments of the present application, on the one hand, by acquiring the captured image of the to-be-processed plate and the processing drawing when it is detected that the to-be-processed plate is placed in the machine tool, the problem of thimble positioning deviation caused by incomplete information or deviation in the placement position of the plate can be effectively reduced. On the other hand, based on the visual information and processing pattern information of the to-be-processed plate obtained, the rotational offset amount of the to-be-processed plate and the preset thimble points are determined. Compared with the traditional method that relies on manual marking of thimble points and visually judges by manual to place the thimble, the present application can accurately calculate the rotational offset amount of the plate relative to the machine tool coordinate system and automatically determine the preset thimble points according to the processing drawing. This improvement eliminates the uncertainty brought by human factors and does not require manual marking of thimble points, which can effectively improve the efficiency and accuracy of determining thimble points. On the third hand, the thimble installation points of the to-be-processed plate relative to the machine tool are determined through the calculated rotational offset amount and preset thimble points. This means that even if there is an angular deflection during the placement of the plate, the present application can calculate and compensate to accurately install the thimble at the thimble installation points. This real-time adjustment and compensation mechanism can ensure that the thimble is always in the accurate installation position, avoid the thimble directly contacting the surface of the to-be-processed plate, and thus prevent the generation of scratches. On the fourth hand, by controlling the movable laser head of the machine tool to move according to the thimble installation points to guide the positioning and installation of the thimble, the accuracy and reliability of thimble positioning can be ensured, and the risk of product scrapping is reduced.

[0105] In one embodiment, as Figure 5 shown, step S20 further includes:

[0106] Step B10, determining the non-pattern area based on the processing pattern information of the to-be-processed plate.

[0107] In this embodiment, the processing pattern information includes the geometric paths and areas of operations such as cutting, drilling, engraving, etc. defined in the processing drawing. The non-pattern area is the area in the processing drawing that is not covered by any processing operations, such as Figure 2 the idle area outside the processing pattern shown.

[0108] In some embodiments, the processing pattern area can be identified from the processing drawing based on the processing pattern information. The difference set operation is performed between the overall area of the processing drawing and the processing pattern area, and the remaining part is the non-pattern area.

[0109] In some embodiments, the processing drawing can also be segmented by the GrabCut algorithm of OpenCV. This algorithm can divide the processing drawing into a processing pattern area and a non-pattern area based on the Gaussian mixture model.

[0110] Step B20: Determine the preset area for the ejector pins based on the distribution characteristics of the non-pattern areas.

[0111] In this embodiment, the distribution characteristics refer to the spatial distribution attributes of the non-pattern areas, such as area, position, shape, etc.

[0112] It can be understood that the non-pattern areas are irregular-shaped areas. To facilitate the screening of the preset area for the ejector pins, the non-pattern areas can be divided into sub-areas according to the continuity of shape transformation, and the distribution characteristics of each sub-area are analyzed respectively to further screen out the preset area for the ejector pins. Analyze whether each sub-area can completely accommodate the minimum area required by the ejector pin, and use the sub-area that can accommodate the minimum area as the preset area for the ejector pins. This minimum area can be the area determined according to the contour shape of the contact area between the ejector pin and the plate to be processed.

[0113] In one implementation, a filtering condition for the preset area for the ejector pins is set in advance, that is, the occupied area of each preset ejector pin position ≥ π × (ejector pin radius + safety margin) 2 , where the safety margin is the minimum distance to prevent the edge of the ejector pin from being too close to the processing path. By analyzing the contour areas of each sub-area, filter out the local areas that cannot accommodate the occupied area of the preset ejector pin position, and the remaining areas are the preset areas for the ejector pins.

[0114] In another implementation, evaluate the shape regularity of each sub-area. Specifically, the circularity of the area can be calculated by the formula (4π × area) / (perimeter 2 ). This formula quantifies the degree of approximation to a circle by comparing the relationship between the area and perimeter of the area. The closer the circularity value is to 1, the closer the area is to a circle and the better the stability. And it can be set that the sub-areas with circularity values < a preset threshold (such as 0.75) are used as unstable areas. Such areas usually show long and narrow or irregular shapes, which may cause uneven distribution of the ejector pin support force and are not suitable for placing ejector pins. Finally, filter out the unstable areas, and the remaining areas are the preset areas for the ejector pins.

[0115] In yet another implementation, calculate the circularity of each sub-area, mark the sub-areas with circularity values greater than the preset threshold as unstable areas, filter the unstable areas to obtain stable areas. Calculate the contour areas of each stable area, and filter out the local areas in each contour area that cannot accommodate the occupied area of the preset ejector pin position to obtain the preset area for the ejector pins.

[0116] Step B30: Obtain the size information and / or weight information of the plate to be processed, and determine the preset number of ejector pins based on the size information and / or weight information.

[0117] In this embodiment, the dimension information includes the length L, width W, and thickness T (unit: millimeter) of the to-be-processed plate. The weight information includes the mass of the to-be-processed plate (unit: kilogram).

[0118] By presetting the minimum bearing capacity, maximum bearing capacity, minimum bearing area, and maximum bearing area of a single thimble, the first guaranteed quantity m1 and the first maximum quantity n1 of the thimbles can be calculated based on the weight information of the to-be-processed plate. The preset quantity of the thimbles can be any suitable value or value range between m1 and n1.

[0119] Further, according to the dimension information of the to-be-processed plate and the preset distribution rule (such as at least 1 thimble every 0.5 and / or at most 5 thimbles every 0.5 ), the second guaranteed quantity m2 and the second maximum quantity n2 of the thimbles can be calculated. The preset quantity of the thimbles can also be any suitable value or value range between m2 and n2.

[0120] Among them, the first guaranteed quantity m1 and the second guaranteed quantity m2 respectively represent the minimum number of thimbles required for the to-be-processed plate calculated from different dimensions, and the first maximum quantity n1 and the second maximum quantity n2 are respectively the maximum number of thimbles required for the to-be-processed plate calculated from different dimensions. The preset quantity of the thimbles can also be any suitable value or value range within the intersection interval formed by the two intervals [m1, n1] and [m2, n2]. For example, the maximum value can be taken from the first guaranteed quantity and the second guaranteed quantity as the preset quantity of the thimbles, so as to place sufficient thimbles on the to-be-processed plate.

[0121] Step B40: Determine the preset thimble points based on the preset thimble area and the preset quantity of the thimbles.

[0122] In this embodiment, based on the preset thimble area and the preset quantity of the thimbles, the preset thimble points are determined according to the preset point distribution rule.

[0123] In one embodiment, the point distribution rule includes uniform distribution, and the preset thimble points are evenly distributed in the preset thimble area according to a grid or a ring.

[0124] In another embodiment, the point distribution rule includes centroid-priority distribution. With the centroid / center of mass of the to-be-processed plate as the center, the preset thimble points are evenly distributed in a ring. It should be noted that if the centroid / center of mass of the to-be-processed plate belongs to the preset thimble area, the preset thimble area to which the centroid / center of mass belongs is the thimble must-set area.

[0125] In some embodiments, the upper limit of the number of preset thimbles can also be calculated based on the distribution characteristics of the preset thimble area and the occupied area of the preset thimble points. The upper limit of the number represents the maximum number of thimbles that can be placed on the to-be-processed sheet.

[0126] It can be understood that each processing pattern will be cut off by the movable laser head in the processing order, thus affecting the overall weight of the to-be-processed sheet and the distribution of the center of gravity. Therefore, when the preset number of thimbles is greater than the upper limit of the number, it means that the number of thimbles that can be placed on the to-be-processed sheet cannot meet the preset number of thimbles. At this time, based on the distribution characteristics of the preset thimble area (or thimble planning area) and the processing pattern information of the to-be-processed sheet, the processing order of each processing pattern and the preset thimble points can be determined, so that after placing the corresponding thimbles based on the preset thimble points, the to-be-processed sheet is processed according to this processing order.

[0127] Specifically, based on the distribution characteristics of the preset thimble area and the preset number of thimbles, the preset thimble points are determined. According to the distribution positions of the preset thimble points, the support center of gravity of the preset thimble points is determined. Based on the support center of gravity and the processing pattern information of the to-be-processed sheet, the processing order of each processing pattern is determined. Processing the processing patterns according to this processing order can make the center of gravity transformation trajectory of the to-be-processed sheet always close to the support center of gravity. In this embodiment, when the number of thimbles that can be placed in the preset thimble area is insufficient to meet the preset number of thimbles, by reasonably arranging the thimble layout, it is possible to prevent the to-be-processed sheet from having an unstable center of gravity and tilting during the processing.

[0128] In the thimble positioning method during the laser processing process proposed in the embodiments of the present application, on the one hand, by accurately extracting the processing pattern information and calculating the non-pattern area, it is ensured that the thimbles will not be placed in the area to be processed, avoiding interference with the processing process. On the other hand, based on the distribution characteristics of the non-pattern area (such as area, position, shape, etc.), and by filtering conditions (such as occupied area, circularity), the part most suitable as the preset thimble area is selected, ensuring the rationality and stability of the thimble layout. On the third hand, by combining the dimension information and the weight information, and comprehensively considering the maximum bearing capacity and distribution rules of a single thimble, it is ensured that the number of thimbles not only meets the support requirements but also does not waste resources excessively. On the fourth hand, according to the support center of gravity corresponding to the layout position of the preset thimble points, the processing order of the processing patterns is dynamically adjusted, so that the thimbles can always provide the best support at different processing stages, improving the resource utilization rate and the processing efficiency.

[0129] In one embodiment, the captured image further includes the sword mountain distribution information of the machine tool, such as Figure 6 As shown, step B40 further includes:

[0130] Step B41: Extract the contour coordinates of the sword-shaped supports based on the distribution information of the sword-shaped supports.

[0131] In this embodiment, the sword-shaped supports are regularly distributed on the machine tool. By capturing the distribution information of the sword-shaped supports in the image and using image processing techniques (such as edge detection and contour recognition), the contour coordinates of the sword-shaped supports can be accurately extracted.

[0132] Step B42: Perform a difference set operation between the contour coordinates of the sword-shaped supports and the preset area of the ejector pins to determine the ejector pin planning area.

[0133] By excluding the intersection of the area occupied by the contour coordinates of the sword-shaped supports and the preset area of the ejector pins from the preset area of the ejector pins, the final ejector pin planning area can be obtained. This step ensures that the ejector pins are not arranged at the positions of the sword-shaped supports, avoiding potential interference problems and improving the safety and efficiency of processing.

[0134] Step B43: Determine the preset positions of the ejector pins based on the ejector pin planning area and the preset number of ejector pins.

[0135] In this embodiment, based on the ejector pin planning area and the preset number of ejector pins, and according to the preset position allocation rules, the preset positions of the ejector pins are determined.

[0136] In one implementation, the position allocation rules include uniform distribution, and the preset positions of the ejector pins are evenly distributed in the ejector pin planning area according to a grid or a ring.

[0137] In another implementation, the position allocation rules include centroid-priority distribution. With the centroid / center of mass of the workpiece to be processed as the center, the preset positions of the ejector pins are evenly distributed in a ring. It should be noted that if the centroid / center of mass of the workpiece to be processed belongs to the ejector pin planning area, the ejector pin planning area to which the centroid / center of mass belongs is the mandatory ejector pin area.

[0138] In some implementations, the upper limit of the preset number of ejector pins can also be calculated based on the distribution characteristics of the ejector pin planning area and the occupied area of the preset ejector pin positions. The upper limit represents the maximum number of ejector pins that can be placed on the workpiece to be processed.

[0139] When the preset number of ejector pins is greater than the upper limit, it means that the number of ejector pins that can be placed on the workpiece to be processed cannot meet the preset number of ejector pins. As one implementation, at this time, based on the distribution characteristics of the ejector pin planning area and the processing drawing information of the workpiece to be processed, the processing sequence of each processing drawing and the preset positions of the ejector pins are determined, so that after placing the corresponding ejector pins according to the preset positions of the ejector pins, the workpiece to be processed is processed according to this processing sequence.

[0140] Specifically, based on the distribution characteristics of the thimble planning area and the preset number of thimbles, the preset thimble points are determined. According to the distribution positions of the preset thimble points, the support center of gravity of the preset thimble points is determined. Based on the support center of gravity and the processing pattern information of the to-be-processed plate, the processing sequence of each processing pattern is determined. Processing the processing patterns in this processing sequence can make the gravity transformation trajectory of the to-be-processed plate always close to the support center of gravity. In this embodiment, when the number of thimbles that can be placed in the thimble planning area is insufficient to meet the preset number of thimbles, by reasonably arranging the processing sequence of the processing patterns, it can prevent the to-be-processed plate from being unstable in gravity and warping during the processing process.

[0141] As another embodiment, since the upper limit of the number of thimbles that can be accommodated in the thimble planning area in this embodiment is affected by the sword mountain contour on the to-be-processed plate. And the sword mountain contour on the to-be-processed plate is related to the placement position of the to-be-processed plate on the machine tool. Therefore, when the preset number of thimbles is greater than the upper limit of the number, a prompt message for re-adjusting the placement position of the to-be-processed plate is sent to prompt the worker to adjust the placement position of the to-be-processed plate. After the worker adjusts, step S10 is re-executed.

[0142] Furthermore, based on the contour coordinates of the sword mountain, the preset number of thimbles, and the thimble preset area, a placement suggestion for re-positioning the to-be-processed plate can be given, so that the sword mountain can avoid the thimble preset area as much as possible to meet the distribution of the preset number of thimbles.

[0143] Specifically, based on the contour coordinates of the sword mountain, the relative position relationship between the sword mountain and the thimble preset area under different plate placement positions is simulated. And from the various simulated relative position relationships, the target relative position relationship with the largest thimble planning area and the largest upper limit of the number of thimbles that can be satisfied is selected. Based on the target relative position relationship, a placement suggestion for the to-be-processed plate is generated.

[0144] In the thimble positioning method during the laser processing process proposed in the embodiments of the present application, on the one hand, by accurately extracting the sword mountain contour coordinates and performing a difference set operation, it is ensured that the thimbles are not arranged at the sword mountain position, avoiding potential interference problems and improving the safety and efficiency of processing. On the other hand, when the preset number of thimbles is greater than the upper limit of the number, by dynamically adjusting the processing sequence of each processing pattern, it can ensure the stable support of the plate and improve the processing accuracy. On the third hand, when the preset number of thimbles exceeds the upper limit of the number that the thimble planning area can accommodate, the worker is guided to adjust the placement position of the to-be-processed plate to increase the area of the thimble planning area, thereby increasing the upper limit of the number that the thimble planning area can accommodate.

[0145] In one embodiment, a computer-readable storage medium is provided, on which executable instructions are stored. When the instructions are executed by a processor, the processor executes the steps in the above method embodiments.

[0146] In one embodiment, an electronic device is further provided, including one or more processors; a memory, where one or more programs are stored in the memory. When the one or more programs are executed by the one or more processors, the one or more processors are caused to execute the steps in the foregoing method embodiments.

[0147] In one embodiment, as Figure 7 shown, it shows a schematic structural diagram of an electronic device for implementing the embodiments of the present application. The electronic device 700 includes a central processing unit (CPU) 701, which can perform various appropriate actions and processes according to the program stored in the read-only memory (ROM) 702 or the program loaded from the storage section 708 into the random access memory (RAM) 703. In the RAM 703, various programs and data required for the operation of the electronic device 700 are also stored. The CPU 701, ROM 702, and RAM 703 are connected to each other via a bus 704. The input / output (I / O) interface 705 is also connected to the bus 704.

[0148] The following components are connected to the I / O interface 705: an input section 706 including a keyboard, a mouse, etc.; an output section 707 including a cathode ray tube (CRT), a liquid crystal display (LCD), etc. and a speaker, etc.; a storage section 708 including a hard disk, etc.; and a communication section 709 including a network interface card such as a LAN card, a modem, etc. The communication section 709 performs communication processing via a network such as the Internet. A drive 710 is also connected to the I / O interface 705 as required. A removable medium 711, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive 710 as required, so that a computer program read from it can be installed into the storage section 708 as required.

[0149] Specifically, according to the embodiments of the present application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, the embodiments of the present application include a computer program product including a computer-readable medium carrying instructions. In such an embodiment, the instructions can be downloaded and installed from the network through the communication section 709, and / or installed from the removable medium 711. When the instructions are executed by the central processing unit (CPU) 701, the various method steps described in the present application are executed.

[0150] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the various embodiments of the present application.

[0151] In addition, those skilled in the art can understand that although some of the embodiments herein include certain features included in other embodiments rather than other features, the combination of the features of different embodiments means that it is within the scope of the present application and forms different embodiments. For example, in the above claims, any one of the claimed embodiments can be used in any combination. The information disclosed in this background art section is only intended to deepen the understanding of the overall background art of the present application, and should not be regarded as an admission or any form of implication that this information constitutes the prior art already known to those skilled in the art.

Claims

1. A method for positioning an ejector pin during laser processing, characterized in that: The method comprises: When it is detected that a plate to be processed is placed in a machine tool, a photographed image and a processing drawing of the plate to be processed are obtained, wherein the photographed image includes visual information of the plate to be processed, and the processing drawing includes processing pattern information of the plate to be processed; Based on the visual information of the plate to be processed and the processing pattern information of the plate to be processed, determining the rotation offset of the plate to be processed and the preset position of the ejector pin; Based on the rotation offset and the preset position of the ejector, determining the installation position of the ejector of the plate to be processed relative to the machine tool; The movable laser head of the machine tool is controlled to move according to the ejector installation point to guide the positioning installation of the ejector.

2. The method for positioning the ejector pin during laser processing according to claim 1, characterized in that: The step of determining the rotation offset of the plate to be processed and the preset position of the ejector pin based on the visual information of the plate to be processed and the processing pattern information of the plate to be processed includes: Based on the visual information of the plate to be processed, first position information of an actual marking point of the plate to be processed compared to an actual coordinate system is acquired; Based on the processing pattern information of the plate to be processed, obtaining second position information of a theoretical marking point of the plate to be processed compared to a machine tool coordinate system; Based on the first position information and the second position information, calculating a position offset matrix from the theoretical marking point to the actual marking point; Based on the position offset matrix, the rotation offset of the plate to be processed in the machine tool coordinate system is determined.

3. The method for positioning the ejector pin during laser processing according to claim 2, characterized in that: Before obtaining the first position information of the actual marking point of the plate to be processed compared to the actual coordinate system, the method further includes: Calibrate the camera of the machine tool to determine the center distance between the movable laser head and the camera, and the ratio of each pixel point in the captured image to the actual physical unit; Based on the center distance and the ratio, the pixel coordinates of each pixel point in the captured image are mapped to an actual coordinate system.

4. The method for positioning the ejector pin during laser processing according to claim 2, characterized in that: After obtaining the first position information of the actual marking point of the plate to be processed compared with the actual coordinate system based on the visual information of the plate to be processed, the method further includes: Controlling a movable laser head of the machine tool to move according to the first position information to collect real-time image information of the actual marking point; Based on the real-time image information, frame a boundary area including the actual marking point; The boundary area is saved as a positioning template.

5. The method for positioning the ejector pin during laser processing according to claim 4, characterized in that: Before saving the boundary area as a positioning template, the method further includes: Selecting a number of data points from the boundary area as test points; Perform feature comparison between the test point and the actual marking point; When the comparison result does not meet the preset comparison standard, the boundary area is adjusted.

6. The method for positioning the ejector pin during laser processing according to claim 1, characterized in that: The step of determining the rotation offset of the plate to be processed and the preset position of the ejector pin based on the visual information of the plate to be processed and the processing pattern information of the plate to be processed includes: Determining a non-pattern area based on the processing pattern information of the plate to be processed; Determining a preset ejector area based on the distribution characteristics of the non-pattern area; Acquiring the size information and / or weight information of the plate to be processed, and determining the preset number of ejector pins based on the size information and / or weight information; Based on the preset ejector pin area and the preset ejector pin quantity, the preset ejector pin positions are determined.

7. The method for positioning the ejector pin during laser processing according to claim 6, characterized in that: The captured image also includes the shank distribution information of the machine tool, and the preset ejector point is determined based on the preset ejector area and the preset ejector number, including: Extracting the contour coordinates of the sword ridge based on the sword ridge distribution information; Performing a difference operation based on the contour coordinates of the sword and the preset ejector area to determine the ejector planning area; Based on the ejector planning area and the ejector preset number, the ejector preset point positions are determined.

8. The method for positioning an ejector pin during laser processing according to any one of claims 1 to 7, characterized in that: The step of determining the installation position of the ejector pin of the plate to be processed relative to the machine tool based on the rotation offset and the preset position of the ejector pin comprises: Based on the rotation offset, a rotation compensation amount and a displacement compensation amount of the preset ejector point are calculated; Based on the rotation compensation amount and the displacement compensation amount, the ejector installation point position corresponding to the ejector preset point position in the machine tool coordinate system is determined.

9. An electronic device, characterized in that: include: one or more processors; a memory for storing one or more programs, When the one or more programs are executed by the one or more processors, the one or more processors execute the ejector positioning method in the laser processing process as described in any one of claims 1 to 8.

10. A storage medium, characterized in that: The storage medium stores executable instructions, and when the instructions are executed by the processor, the processor executes the ejector positioning method in the laser processing process according to any one of claims 1 to 8.

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