A three-dimensional quantitative analysis method for failure fracture of fiber-reinforced composite materials

Abstract

The present invention discloses a three-dimensional quantitative analysis method for failure fractures of fiber-reinforced composite materials. The method comprises the following steps: selecting sub-volumes from XCT data of the fiber-reinforced composite material; analyzing the fibers using a cylindrical equivalent method, and calculating the normalized cross-correlation field data and orientation field data of the fibers at the fracture in the sub-volumes; calculating the spatial position traces of the fiber filaments in the XCT data, and displaying the three-dimensional spatial distribution of the fibers at the fracture by selecting a cylinder with an equivalent diameter. The spatial distribution, pull-out length, and fiber orientation data of the fibers at the fracture of the fiber-reinforced composite material are simultaneously obtained, and the fracture characteristics of individual fibers in the fiber-reinforced composite material are quantitatively analyzed; and sub-volumes of fiber bundle fractures at different spatial positions in the complete fiber-reinforced composite material are selected to perform three-dimensional quantitative analysis of the fiber-reinforced composite material fracture. The present invention achieves quantitative analysis of failure fractures of fiber-reinforced composite materials.

Description

Technical Field

[0001] The present invention relates to the field of structural failure mechanism analysis, and in particular to a three-dimensional quantitative analysis method for failure fractures of fiber-reinforced composite materials. Background Art

[0002] Fiber-reinforced composites, primarily composed of reinforcing fibers and a matrix, have the advantages of low density, high specific strength, and strong designability, making them the material of choice in aerospace, medical, shipbuilding, automotive, and other engineering fields. As a multiphase composite material, the mechanical properties and damage behavior of fiber-reinforced composites depend not only on the material properties of each component, but also on the microstructural characteristics of the material. Therefore, rapidly quantifying and analyzing the failure characteristics of composite materials at the microscale and proposing corresponding improvement measures can greatly improve the reliability of composite structures, thereby ensuring the lifespan and safety of fiber-reinforced composites during use.

[0003] Fracture analysis of composite materials is an important means of revealing their failure characteristics. However, fracture morphology has significant spatial characteristics, and achieving quantitative fracture analysis in three dimensions is an urgent need in engineering applications. Scanning electron microscopy and optical microscopy are commonly used to characterize and analyze the fracture morphology of fiber-reinforced composites, but these two analytical methods still have many shortcomings. For example, when using scanning electron microscopy for observation and analysis, the material being observed must be placed in a vacuum environment, and only the surface morphology of the material fracture can be observed. Furthermore, no height information is available during the observation process, resulting in only a two-dimensional planar image of the fracture. Although optical microscopy does not require vacuum observation, it also suffers from the lack of effective height information, and the resolution of optical microscopy observations is far lower than that of scanning electron microscopy. Therefore, observation methods based on scanning electron microscopy and optical microscopy cannot meet the requirements for three-dimensional quantitative analysis of fiber-reinforced composite fractures. Although XCT analysis of fiber-reinforced composite fractures can obtain three-dimensional fracture data, there is no effective quantitative analysis method for the microscopic characteristics of the fracture.

[0004] Therefore, it is necessary to provide a method for three-dimensional quantitative analysis of the fracture of fiber-reinforced composite materials, realize three-dimensional quantitative analysis of the fracture morphology, reveal the failure mechanism of fiber-reinforced composite materials, and provide support for the reliable engineering application of fiber-reinforced composite materials. Summary of the Invention

[0005] In order to solve the problem of three-dimensional quantitative analysis of failure fractures of fiber reinforced composite materials, the present invention proposes a three-dimensional quantitative analysis method for failure fractures of fiber reinforced composite materials, which realizes the quantitative analysis of failure fractures of fiber reinforced composite materials.

[0006] In order to achieve the above technical objectives, the technical solution adopted by the present invention is:

[0007] A three-dimensional quantitative analysis method for failure fracture of a fiber-reinforced composite material, the three-dimensional quantitative analysis method comprising the following steps:

[0008] Step 1: Scan the fiber-reinforced composite material through XCT to obtain the corresponding original XCT data G (X, Y, Z);

[0009] Step 2: Binarize and denoise the XCT data G(X, Y, Z) in step 1 to obtain XCT data G1(X, Y, Z) with noise and pore information removed.

[0010] Step 3: Select the sub-volume of the XCT data G1 (X, Y, Z) of the fiber reinforced composite material; specifically, select the fiber bundle fracture sub-volume g1 (X, Y, Z) with the lower left corner of the fiber reinforced composite material fracture as the starting point, and then select a complete fracture fiber bundle one by one along the thickness direction of the fiber reinforced composite material as the analysis object, and cut to obtain the XCT data g1 (X, Y, Z) of the fiber bundle fracture sub-volume. n (X, Y, Z), n=1, 2,...,N;

[0011] Step 4: XCT data of the fiber bundle fracture subvolume obtained based on the cutting n (X, Y, Z), the cylindrical equivalent method is used to analyze the fiber, and the following calculation parameters are set: equivalent cylinder length, angle sampling, equivalent cylinder radius and contrast, and the normalized cross-correlation field data and direction field data of the fiber at the break in the subvolume are calculated;

[0012] Step 5: Based on XCT data g n The normalized cross-correlation field data and direction field data of (X, Y, Z) are used to calculate the XCT data g n The spatial position trace line of the fiber single filament in (X, Y, Z) is used to display the three-dimensional spatial distribution of the fiber at the fracture by selecting a cylinder with an equivalent diameter. At the same time, the spatial distribution, pull-out length and fiber direction data of the fiber at the fracture of the fiber-reinforced composite material are obtained, and the fracture characteristics of the local single fiber of the fiber-reinforced composite material are quantitatively analyzed;

[0013] Step 6: Repeat steps 3 to 5, select the fiber bundle fracture sub-volumes at different spatial positions of the complete fiber-reinforced composite material, and obtain the spatial distribution, pull-out length, and direction of the fiber pull-out at the corresponding fracture; compare and analyze the fracture data at different spatial positions, and perform a three-dimensional quantitative analysis of the fiber-reinforced composite material fracture.

[0014] The step 2 further comprises:

[0015] Based on the grayscale value difference of each part of the XCT image, the threshold segmentation algorithm is used to select the appropriate threshold T to obtain the binary XCT data g(X, Y, Z), where f(x, y, z) is the grayscale value at the coordinate (x, y, z) in the XCT data:

[0016]

[0017] Through image multiplication operation, the XCT data G1 (X, Y, Z) with noise removed and pore information is obtained:

[0018] G1(x,y,z)=G(x,y,z)×g(x,y,z).

[0019] The step three further comprises:

[0020] During the selection process, first select upward, then select rightward until the characteristics of the selected fiber bundle fracture meet the analysis requirements, and record the center point position p of the sub-volume in three-dimensional space. n (X, Y, Z).

[0021] The step 4 further comprises:

[0022] The equivalent cylinder length is set according to the actual fiber radius; the sampling angle is set according to the calculation accuracy and calculation amount, and the value of the sampling angle is inversely proportional to the calculation accuracy and calculation amount; the equivalent cylinder length is set according to the straight line structure, and the larger the value of the equivalent cylinder length, the more sensitive it is to the straight line structure; the brightness contrast between the target and the environment is selected as the contrast.

[0023] The step five further comprises:

[0024] During the calculation, relevant parameters are set first: minimum seed correlation, minimum continuation quality, direction coefficient, and minimum distance between center lines; the larger the value of the minimum seed correlation, the higher the correlation and the higher the reliability; the smaller the value of the direction coefficient, the higher the straightness of the fiber trace line; the minimum continuation quality is used to control the continuation quality of the fiber trace line; the minimum distance between center lines is used to control the minimum spacing between trace lines to prevent repeated marking of the same fiber.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] First, the three-dimensional quantitative analysis method of the failure fracture of fiber-reinforced composite materials of the present invention pre-processes the fiber-reinforced composite materials and proposes a method for selecting sub-volumes of fiber-reinforced composite materials. By quantitatively analyzing multiple trimmed sub-volumes, the method moves from local position analysis of the fracture to quantitative analysis of the complete fracture, thereby improving the efficiency of quantitative analysis of the failure fracture of fiber-reinforced composite materials.

[0027] Second, the three-dimensional quantitative analysis method of the failed fracture of the fiber-reinforced composite material of the present invention calculates the normalized cross-correlation field and direction field of the fracture of the fiber-reinforced composite material through XCT data, extracts the three-dimensional spatial distribution of the fibers at the fracture, obtains the spatial coordinate position, fiber pull-out length, and fiber direction of the fibers at the fracture, realizes the quantitative analysis of the fracture of the fiber-reinforced composite material, and solves the problem of high cost of manual calibration analysis.

[0028] Third, the three-dimensional quantitative analysis method of the failure fracture of the fiber-reinforced composite material of the present invention has a clear process logic relationship, can be programmed to realize the quantitative analysis of the failure fracture of the fiber-reinforced composite material, realizes the processing of big data at one time, has a simple and convenient operation process, and the three-dimensional quantitative analysis results of the fracture are more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a flow chart of the three-dimensional quantitative analysis method for failure fracture of fiber-reinforced composite materials of the present invention;

[0030] Figure 2 The original image and the pre-treated image of the plain woven fiber reinforced ceramic matrix composite material of the present invention;

[0031] Figure 3 A three-dimensional fracture diagram of the plain woven fiber reinforced ceramic matrix composite material after pretreatment in the present invention;

[0032] Figure 4 is a cut-out subvolume cross-section diagram in the present invention;

[0033] Figure 5 is a three-dimensional image of the cropped subvolume in the present invention;

[0034] Figure 6 The normalized cross-correlation field map of the XY slice of the cropped subvolume in the present invention;

[0035] Figure 7 It is the XY section directional field map of the sub-volume cut in the present invention;

[0036] Figure 8 This is the fiber spatial distribution diagram at the fracture of the sub-volume cut in the present invention;

[0037] Figure 9 A diagram showing the quantitative analysis results of the clipped subvolume in the present invention in a three-dimensional diagram;

[0038] Figure 10 This is a diagram showing the quantitative analysis results of the fiber pull-out length at different positions along the thickness direction in the present invention. DETAILED DESCRIPTION

[0039] The embodiments of the present invention are described in further detail below with reference to the accompanying drawings.

[0040] The present invention discloses a three-dimensional quantitative analysis method for failure fracture of fiber reinforced composite materials, the three-dimensional quantitative analysis method comprising the following steps:

[0041] Step 1: Scan the fiber-reinforced composite material through XCT to obtain the corresponding original XCT data G (X, Y, Z);

[0042] Step 2: Binarize and denoise the XCT data G(X, Y, Z) in step 1 to obtain XCT data G1(X, Y, Z) with noise and pore information removed.

[0043] Step 3: Select the sub-volume of the XCT data G1 (X, Y, Z) of the fiber reinforced composite material; specifically, select the fiber bundle fracture sub-volume g1 (X, Y, Z) with the lower left corner of the fiber reinforced composite material fracture as the starting point, and then select a complete fracture fiber bundle one by one along the thickness direction of the fiber reinforced composite material as the analysis object, and cut to obtain the XCT data g1 (X, Y, Z) of the fiber bundle fracture sub-volume. n (X, Y, Z), n=1, 2,...,N;

[0044] Step 4: XCT data of the fiber bundle fracture subvolume obtained based on the cutting n (X, Y, Z), the cylindrical equivalent method is used to analyze the fiber, and the following calculation parameters are set: equivalent cylinder length, angle sampling, equivalent cylinder radius and contrast, and the normalized cross-correlation field data and direction field data of the fiber at the break in the subvolume are calculated;

[0045] Step 5: Based on XCT data g n The normalized cross-correlation field data and direction field data of (X, Y, Z) are used to calculate the XCT data g n The spatial position trace line of the fiber single filament in (X, Y, Z) is used to display the three-dimensional spatial distribution of the fiber at the fracture by selecting a cylinder with an equivalent diameter. At the same time, the spatial distribution, pull-out length and fiber direction data of the fiber at the fracture of the fiber-reinforced composite material are obtained, and the fracture characteristics of the local single fiber of the fiber-reinforced composite material are quantitatively analyzed;

[0046] Step 6: Repeat steps 3 to 5, select the fiber bundle fracture sub-volumes at different spatial positions of the complete fiber-reinforced composite material, and obtain the spatial distribution, pull-out length, and direction of the fiber pull-out at the corresponding fracture; compare and analyze the fracture data at different spatial positions, and perform a three-dimensional quantitative analysis of the fiber-reinforced composite material fracture.

[0047] See also Figure 1 , the three-dimensional quantitative analysis method specifically includes the following steps:

[0048] Step 1: First, scan the fiber-reinforced composite material through XCT to obtain the corresponding XCT data G (X, Y, Z). The specific embodiment of the present invention is a plain woven fiber-reinforced ceramic matrix composite material. The corresponding XCT data size is 4448px × 3242px × 2057px, the type is 16bit, and the scanning resolution is 2μm; Figure 2 (A) in the figure shows the original data diagram of the plain woven fiber reinforced ceramic matrix composite material selected in this example, including: (a) XY section diagram, (b) XZ section diagram, and (c) YZ section diagram.

[0049] Step 2: Preprocess the XCT data G(X, Y, Z) obtained in step 1. In this example, the image grayscale threshold segmentation algorithm (Formula 1) is used to Figure 2 The XCT data shown in (A) is segmented with a segmentation threshold T of 10347 to obtain a binary image. The noise and pores in the G(X, Y, Z) image are removed by image multiplication (Formula 2) to obtain an XCT dataset G1(X, Y, Z) containing only fiber-reinforced composite material entities. Figure 2 (B) shows the cross-section of the pre-processed XCT data, which excludes the background noise and pores (the background is converted to pure black); the fracture morphology of the plain woven fiber reinforced ceramic matrix composite in three-dimensional space is shown in Figure 3 shown.

[0050]

[0051] G1(x,y,z)=G(x,y,z)×g(x,y,z) (2)

[0052] Step 3: Select the sub-volume of XCT data G1 (X, Y, Z) of the fiber reinforced composite material. In this example, the fracture fiber bundle sub-volume g1 (X, Y, Z) is selected starting from the lower left corner of the plain woven fiber reinforced composite material. Then, along the thickness direction of the fiber reinforced composite material, a complete fracture fiber bundle g is selected one by one from the outer surface to the inner surface. n (X, Y, Z) (n = 2, 3, 4, 5, 6) as the analysis object. The selection principle is: during the selection process, if the characteristics of the selected fiber bundle fracture cannot meet the analysis requirements (fiber adhesion is tight, no obvious fiber pullout), then select to the right. If none of them meet the requirements, repeat this operation (select upward first, then select to the right), and record the center point position p of the selected sub-volume in three-dimensional space. n (X, Y, Z) (n=1, 2, 3, 4, 5, 6). like Figure 3 The following are the fracture surfaces of 6 individual fiber bundles selected in this example. n(X, Y, Z) for subsequent quantitative analysis to improve analysis efficiency. Figure 4 Shown Figure 3 Schematic diagram of the cross-section of the fiber bundle fracture subvolume g1 (X, Y, Z) in different directions, as shown in Figure 5 Shown is a three-dimensional topography image of the subvolume g1 (X, Y, Z).

[0053] Step 4: Based on the XCT data g1 (X, Y, Z) of the cropped subvolume, the cylindrical equivalent fiber method is used to calculate the normalized cross-correlation field and direction field of the fibers at the break in the subvolume g1 (X, Y, Z). Before the calculation, the calculation parameters of the normalized cross-correlation field and the direction field are first set, including: equivalent cylinder length, angle sampling, equivalent cylinder radius, and contrast. (Equivalent cylinder radius: set according to the actual fiber radius; sampling angle: the smaller the value, the higher the calculation accuracy and the larger the calculation amount; equivalent cylinder length: the larger the value, the more sensitive to the straight structure; contrast: select the light and dark contrast between the target and the environment) The parameters used in the subvolume g1 (X, Y, Z) in this example are: equivalent cylinder length is 20μm, sampling angle parameter is 5, equivalent cylinder radius is 6μm, and contrast is selected as bright on dark (bright and dark refers to the grayscale value of the fiber and the surrounding background that needs to be equivalent. As shown in the figure, Figure 4 Three different sections are shown, with the equivalent target being bright and the background being dark). Based on this calculation, the normalized cross-correlation field of the fiber is obtained as follows: Figure 6 As shown and the direction field as Figure 7 shown.

[0054] Step 5: Based on the relevant field data and directional field data of g1 (X, Y, Z) obtained in step 4, the spatial position trace line of the fiber monofilament in g1 (X, Y, Z) is calculated, which contains statistical information such as the direction and length of the fiber. Based on the above statistical information, the pull-out length of the fiber at the fracture of the fiber-reinforced composite material is obtained to achieve quantitative analysis of the failure fracture of a local single fiber-reinforced composite material. During the calculation, the relevant parameters are first set: minimum seed correlation, minimum continuation quality, directional coefficient, minimum distance between center lines and other parameters. (Minimum seed correlation: the larger the value, the higher the correlation and the higher the reliability; directional coefficient: the smaller the value, the higher the straightness of the fiber trace line; minimum continuation quality: controls the continuation quality of the fiber trace line; minimum distance between center lines: controls the minimum spacing between trace lines to prevent repeated marking of the same fiber.) In this example, the parameters of subvolume 1 are set as follows: the minimum seed correlation value is 128, the minimum continuation quality value is 45, the directional curvature value is 0.3, and the minimum center line distance is 8μm. The calculated spatial distribution of fibers at the fracture is displayed by selecting a cylinder of appropriate diameter. Figure 8 is the spatial distribution of fibers at the fracture of subvolume 1 and the image scale. Figure 5Combined display results such as Figure 9 shown and in Figure 9 The lengths of some fibers are marked in the figure.

[0055] Step 6: Repeat steps 3 to 5 to select the fiber bundle fracture sub-volume g at different spatial positions of the complete fiber reinforced composite material. n (X, Y, Z), complete the quantitative analysis of the fiber bundle fracture at different positions; in this example, only the pull-out length distribution of the fracture fiber along the thickness direction (Z direction) is analyzed, according to the center point p in the three-dimensional space of the six fiber bundle fracture sub-volumes recorded in step 3 n (X, Y, Z), the voxel difference Δz between the center point and the inner surface in the Z direction of the fracture subvolume was calculated, and the distance between the fracture subvolume and the inner surface was calculated based on the actual length of each voxel. The fiber pull-out length at different positions of the fracture was counted, and the distribution of the fiber pull-out length at the fracture from the inner surface to the outer surface was analyzed. The results are as follows Figure 10 As shown in the figure, along the thickness direction of the fiber reinforced composite material, the farther away from the inner surface of the fracture, the longer the fiber pullout at the fracture.

[0056] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code. The scheme in the embodiment of the present application can be implemented in various computer languages, for example, object-oriented programming language Java and literal translation scripting language JavaScript, etc.

[0057] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0058] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0059] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions for executing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0060] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present application.

[0061] Obviously, those skilled in the art may make various changes and modifications to this application without departing from the spirit and scope of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalents, this application is intended to include these modifications and variations.

Claims

1. A three-dimensional quantitative analysis method for failure fracture of fiber reinforced composite materials, characterized in that: The three-dimensional quantitative analysis method comprises the following steps: Step 1: Scan the fiber-reinforced composite material through XCT to obtain the corresponding original XCT data G (X, Y, Z); Step 2: Binarize and denoise the XCT data G(X, Y, Z) in step 1 to obtain XCT data G1(X, Y, Z) with noise and pore information removed. Step 3: Select the sub-volume of the XCT data G1(X, Y, Z) of the fiber reinforced composite material; specifically, select the fiber bundle fracture sub-volume g1(X, Y, Z) with the lower left corner of the fiber reinforced composite material fracture as the starting point, and then select a complete fracture fiber bundle one by one along the thickness direction of the fiber reinforced composite material as the analysis object, and cut to obtain the XCT data g1(X, Y, Z) of the fiber bundle fracture sub-volume n (X, Y, Z), n = 1, 2, ..., N; Step 4: XCT data of the fiber bundle fracture subvolume obtained based on the cutting n (X, Y, Z), the cylindrical equivalent method is used to analyze the fiber, and the following calculation parameters are set: equivalent cylinder length, angle sampling, equivalent cylinder radius and contrast, and the normalized cross-correlation field data and direction field data of the fiber at the break in the subvolume are calculated; Step 5: Based on XCT data g n The normalized cross-correlation field data and direction field data of (X, Y, Z) are used to calculate the XCT data g n The spatial position trace line of the fiber single filament in (X, Y, Z) is used to display the three-dimensional spatial distribution of the fiber at the fracture by selecting a cylinder with an equivalent diameter. At the same time, the spatial distribution, pull-out length and fiber direction data of the fiber at the fracture of the fiber-reinforced composite material are obtained, and the fracture characteristics of the local single fiber of the fiber-reinforced composite material are quantitatively analyzed; Step 6: Repeat steps 3 to 5, select the fiber bundle fracture sub-volumes at different spatial positions of the complete fiber-reinforced composite material, and obtain the spatial distribution, pull-out length, and direction of the fiber pull-out at the corresponding fracture; compare and analyze the fracture data at different spatial positions, and perform a three-dimensional quantitative analysis of the fiber-reinforced composite material fracture.

2. The three-dimensional quantitative analysis method for failure fracture of fiber reinforced composite materials according to claim 1, characterized in that: The step 2 further comprises: Based on the grayscale value difference of each part of the XCT image, the threshold segmentation algorithm is used to select the appropriate threshold T to obtain the binary XCT data g(X,Y,Z), where f(x,y,z) is the grayscale value at the coordinate (x,y,z) in the XCT data: Through image multiplication operation, the XCT data G1 (X, Y, Z) with noise and pore information removed is obtained: G1(x,y,z)=G(x,y,z)×g(x,y,z).

3. The three-dimensional quantitative analysis method for failure fracture of fiber reinforced composite materials according to claim 1, characterized in that: The step three further comprises: During the selection process, first select upward, then select rightward until the characteristics of the selected fiber bundle fracture meet the analysis requirements, and record the center point position p of the sub-volume in three-dimensional space. n (X,Y,Z).

4. The three-dimensional quantitative analysis method for failure fracture of fiber reinforced composite materials according to claim 1, characterized in that: The step 4 further comprises: The equivalent cylinder length is set according to the actual fiber radius; the sampling angle is set according to the calculation accuracy and calculation amount, and the value of the sampling angle is inversely proportional to the calculation accuracy and calculation amount; the equivalent cylinder length is set according to the straight line structure, and the larger the value of the equivalent cylinder length, the more sensitive it is to the straight line structure; the brightness contrast between the target and the environment is selected as the contrast.

5. The three-dimensional quantitative analysis method for failure fracture of fiber reinforced composite materials according to claim 1, characterized in that: The step five further comprises: During the calculation, relevant parameters are set first: minimum seed correlation, minimum continuation quality, direction coefficient, and minimum distance between center lines; the larger the value of the minimum seed correlation, the higher the correlation and the higher the reliability; the smaller the value of the direction coefficient, the higher the straightness of the fiber trace line; the minimum continuation quality is used to control the continuation quality of the fiber trace line; the minimum distance between center lines is used to control the minimum spacing between trace lines to prevent repeated marking of the same fiber.

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