Three-dimensional printing path planning method based on carbon fiber reinforced matrix, three-dimensional printing method and electronic equipment

Abstract

The invention relates to the field of three-dimensional printing of carbon fibers, in particular to a three-dimensional printing path planning method based on a carbon fiber reinforced matrix, a three-dimensional printing method and electronic device.The planning method comprises the steps that finite element analysis is conducted on a three-dimensional model of the matrix, and a stress vector set is obtained; generating multiple layers of contour lines corresponding to the outer surface of the three-dimensional model; m stress vectors borne by each equidistant point on the isoline are determined; m angle values corresponding to each equidistant point on each layer of isoline are obtained; according to the M angle values corresponding to each equidistant point in the N equidistant points on each layer of isoline, determining J deviation angle values corresponding to each layer of isoline; and generating a carbon fiber printing path corresponding to each carbon fiber winding layer in the J carbon fiber winding layers according to the J deviation angle values corresponding to each layer of isoline in the multiple layers of isolines. Therefore, the three-dimensional carbon fiber printing path adopted when the carbon fiber reinforced matrix is used can be effectively determined.

Description

Technical Field

[0001] The present disclosure relates to the field of three-dimensional printing of carbon fiber, and particularly to a three-dimensional printing path planning method, a three-dimensional printing method, and an electronic device based on a carbon fiber reinforced matrix. Background Art

[0002] Carbon fiber has gradually become an important part of advanced composite materials. With the continuous progress of domestic carbon fiber raw material production technology, carbon fiber tows of models such as T300 and T700 have been mass-produced. Due to its excellent strength-to-weight ratio, corrosion resistance, and high-temperature stability, it has been widely used in mid- to high-end manufacturing fields such as aerospace, automotive, and wind energy. At the same time, the rapid development of thermoplastic carbon fiber provides new possibilities for the digital manufacturing of carbon fiber, laying a foundation for its application in emerging manufacturing technologies such as 3D printing.

[0003] In recent years, the rise of 3D printing technology has effectively reduced manufacturing costs and improved production efficiency. However, most current technologies still focus on the application of short fiber composites. Due to the limitation of fiber length, the reinforcement effect of short fibers is far inferior to that of continuous carbon fibers. Especially in the manufacturing of high-performance structural parts, the advantages of continuous carbon fibers in structural reinforcement cannot be fully utilized. Moreover, the current path generation methods used in 3D printing mostly involve path planning methods such as straight-line back-and-forth filling, contour offset filling, and hybrid path filling within a two-dimensional plane slice. These methods are difficult to apply to 3D printing scenarios where continuous carbon fibers are used to print carbon fiber reinforced layers on the surface of a matrix in three-dimensional space to improve the load-bearing capacity of the matrix. Summary of the Invention

[0004] In view of this, the present disclosure provides a three-dimensional printing path planning method, a three-dimensional printing method, and an electronic device based on a carbon fiber reinforced matrix, which can effectively determine a three-dimensional multi-layer carbon fiber printing path, and enable the carbon fiber reinforced layer printed according to the multi-layer three-dimensional carbon fiber printing path to greatly improve the load-bearing capacity of the matrix, with higher printing efficiency and more savings in carbon fiber materials.

[0005] According to one aspect of the present disclosure, a three-dimensional printing path planning method for a carbon fiber reinforced matrix is provided, including: obtaining a stress vector set corresponding to the matrix by performing finite element analysis on a three-dimensional model of the matrix to be reinforced, where the stress vector set characterizes the distribution of stress vectors received by the matrix under each of M kinds of loadings; generating multi-layer contour lines corresponding to the outer surface of the three-dimensional model, and each layer of contour lines includes N equally spaced points evenly distributed; determining M stress vectors received by each equally spaced point on each layer of contour lines according to the stress vector set, where the M stress vectors received by each equally spaced point include the stress vectors received by each equally spaced point under each of the M kinds of loadings; calculating the angles between the M stress vectors received by each equally spaced point on each layer of contour lines and the tangent vector of the equally spaced point on the contour line to which it belongs, respectively, to obtain M angle values corresponding to each equally spaced point on each layer of contour lines; determining J offset angle values corresponding to each layer of contour lines according to the M angle values corresponding to each equally spaced point among the N equally spaced points on each layer of contour lines, where the J offset angle values correspond to J carbon fiber winding layers; generating a carbon fiber printing path corresponding to each carbon fiber winding layer among the J carbon fiber winding layers according to the J offset angle values corresponding to each layer of contour lines in the multi-layer contour lines.

[0006] In a possible implementation, there is an association relationship between the equally spaced points on adjacent contour lines in the multi-layer contour lines, and the association relationship is used to indicate the equally spaced points associated with each other on adjacent contour lines; wherein, the step of generating a carbon fiber printing path corresponding to each carbon fiber winding layer among the J carbon fiber winding layers according to the J offset angle values corresponding to each layer of contour lines in the multi-layer contour lines includes: for the j-th carbon fiber winding layer among the J carbon fiber winding layers, offsetting the N equally spaced points on each layer of contour lines according to the offset angle value corresponding to the j-th carbon fiber winding layer of each layer of contour lines and the average layer height of the multi-layer contour lines to obtain N target equally spaced points after offset on each layer of contour lines, 1≤j≤J; and connecting the target equally spaced points associated with each other between adjacent contour lines in the multi-layer contour lines according to the association relationship between the equally spaced points on adjacent contour lines in the multi-layer contour lines and the N target equally spaced points after offset on each layer of contour lines, to obtain the carbon fiber printing path corresponding to the j-th carbon fiber winding layer.

[0007] In a possible implementation, generating the multi-layer contour lines corresponding to the outer surface of the three-dimensional model includes: performing triangular meshing on the outer surface corresponding to the three-dimensional model to obtain a three-dimensional mesh model, where the three-dimensional mesh model represents the triangular meshed outer surface; determining the distance field corresponding to the three-dimensional model according to the positions of the grid points in the three-dimensional mesh model, where the distance field includes the distances from each grid point in the three-dimensional mesh model to a specified surface of the three-dimensional model, and the specified surface includes the edge surfaces at both ends of the three-dimensional model; generating the multi-layer contour lines corresponding to the outer surface of the three-dimensional model based on the distance field and a preset average layer height, where the seam positions between the multi-layer contour lines are aligned and the generation directions are the same; extracting N equally spaced points uniformly distributed on each layer of contour lines according to a preset average distance, and the N equally spaced points extracted on each layer of contour lines are aligned with each other, and determining the equally spaced points aligned with each other on adjacent contour lines in the multi-layer contour lines as corresponding associated equally spaced points, to obtain the association relationship between the equally spaced points on adjacent contour lines in the multi-layer contour lines, where the average distance represents the distance between two adjacent equally spaced points on the same contour line.

[0008] In a possible implementation, determining the J offset angle values corresponding to each layer of contour lines according to the M angle values corresponding to each of the N equally spaced points on each layer of contour lines includes: for the N×M angle values on the x-th layer of contour lines, determining whether each of the N×M angle values is within a preset angle range, and in the case where there are angle values among the N×M angle values that do not belong to the preset angle range, correcting the angle values that do not belong to the preset angle range to the boundary value closest to the angle value in the preset angle range, to obtain the N×M target angle values corresponding to the N equally spaced points on the x-th layer of contour lines, where the preset angle range represents the angle range that can enable carbon fiber to wind around the matrix; obtaining J angle groups divided by the N×M target angle values within the preset angle range and the central angle value corresponding to each of the J angle groups through statistical grouping of the N×M target angle values, and the central angle value corresponding to each angle group is the angle value with the smallest sum of distances from each target angle value within each angle group; determining the J offset angle values corresponding to the x-th layer of contour lines as the central angle values corresponding to the J angle groups respectively.

[0009] In a possible implementation, the preset angle range includes two opposite angle ranges, r angle groups are divided within each angle range, 2r = J, and the J offset angle values corresponding to the x-th layer of contour lines include the central angle values corresponding to the r angle groups divided within each of the two opposite angle ranges by the N×M target angle values.

[0010] In a possible implementation, for the j-th carbon fiber winding layer among the J carbon fiber winding layers, according to the offset angle value corresponding to the j-th carbon fiber winding layer for each layer of contour lines and the average layer height of the multi-layer contour lines, the N equally spaced points on each layer of contour lines are offset to obtain N target equally spaced points after offset on each layer of contour lines, including: for the x-th layer of contour lines of the j-th carbon fiber winding layer among the J carbon fiber winding layers, determining the offset amount of the x-th layer of contour lines under the j-th carbon fiber winding layer according to the offset angle value corresponding to the x-th layer of contour lines in the j-th carbon fiber winding layer and the average layer height; by accumulating the offset amount of the 1st layer of contour lines under the j-th carbon fiber winding layer to the offset amount of the x-th layer of contour lines under the j-th carbon fiber winding layer, obtaining the accumulated offset amount of the x-th layer of contour lines under the j-th carbon fiber winding layer; and offsetting the N equally spaced points on the x-th layer of contour lines along the x-th layer of contour lines by the accumulated offset amount to obtain N target equally spaced points after offset on the x-th layer of contour lines.

[0011] In a possible implementation, the offset amount of the x-th layer of contour lines under the j-th carbon fiber winding layer is expressed as: , and the accumulated offset amount of the x-th layer of contour lines under the j-th carbon fiber winding layer is expressed as ; where represents the average layer height, and represents the offset angle value corresponding to the x-th layer of contour lines in the j-th carbon fiber winding layer.

[0012] In a possible implementation, according to the correlation relationship between the equally spaced points on adjacent contour lines among the multi-layer contour lines and the N target equally spaced points after offset on each layer of contour lines, corresponding connections are made to the target equally spaced points associated between adjacent contour lines among the multi-layer contour lines to obtain the carbon fiber printing path corresponding to the j-th carbon fiber winding layer, including: according to the correlation relationship between the equally spaced points on adjacent contour lines among the multi-layer contour lines and the N target equally spaced points after offset on each layer of contour lines, making corresponding connections to the target equally spaced points associated between adjacent contour lines among the multi-layer contour lines, and softening the connection result to obtain the carbon fiber printing path corresponding to the j-th carbon fiber winding layer.

[0013] According to another aspect of the present disclosure, a three-dimensional printing method for a carbon fiber reinforced matrix is provided. The printing method is applied to a three-dimensional printing system, which includes a main robotic arm, an auxiliary robotic arm, a carbon fiber print head, and a matrix fixing frame. The carbon fiber print head is installed on the auxiliary robotic arm, and the matrix fixing frame is installed on the main robotic arm. The carbon fiber print head is used to generate carbon fiber filaments, and the matrix fixing frame is used to fix the matrix to be reinforced. The printing method includes: using the path planning method described above to determine the three-dimensional printing path planning result corresponding to the matrix, where the three-dimensional printing path planning result includes the carbon fiber printing paths corresponding to each carbon fiber winding layer in the J carbon fiber winding layers; according to the three-dimensional printing path planning result, determining the motion instructions of the main robotic arm and the auxiliary robotic arm during the printing process respectively; and based on the motion instructions of the main robotic arm and the auxiliary robotic arm during the printing process respectively, controlling the three-dimensional printing system to perform the printing work of the carbon fiber reinforced layer on the matrix.

[0014] In a possible implementation, the matrix includes a matrix with the same cross-sectional shape and the same cross-sectional area between two ends; the matrix fixed to the matrix fixing frame is in a flat and inverted state. Among them, the step of determining the motion instructions of the main robotic arm and the auxiliary robotic arm during the printing process respectively according to the three-dimensional printing path planning result includes: according to the three-dimensional printing path planning result, determining the matrix rotation data corresponding to each carbon fiber printing path in each carbon fiber winding layer, where the matrix rotation data includes the rotation angle of the matrix during the printing process by the carbon fiber print head along each carbon fiber printing path; and according to the matrix rotation data corresponding to each carbon fiber printing path in each carbon fiber winding layer, determining the motion instructions of the main robotic arm and the auxiliary robotic arm during the printing process respectively.

[0015] According to another aspect of the present disclosure, an electronic device is provided, including: a processor; a memory for storing instructions executable by the processor; wherein, the processor is configured to implement the above method when executing the instructions stored in the memory.

[0016] According to another aspect of the present disclosure, a non-volatile computer-readable storage medium is provided, on which computer program instructions are stored. When the computer program instructions are executed by a processor, the above method is implemented.

[0017] According to another aspect of the present disclosure, a computer program product is provided, including computer-readable code, or a non-volatile computer-readable storage medium carrying the computer-readable code. When the computer-readable code runs in the processor of an electronic device, the processor in the electronic device executes the above method.

[0018] According to various aspects of the present disclosure, obtaining a set of stress vectors through finite element analysis of the three-dimensional model of the matrix is equivalent to obtaining the stress distribution of the matrix under various loads. Furthermore, based on the stress distribution, determining the offset angle values of equally spaced points on the isoline can make the offset angle values of each equally spaced point on each layer of the isoline uniform, and is conducive to making the arrangement of the printing paths in each carbon fiber winding layer relatively uniform and covering the stress distributions in multiple directions of the matrix. Then, based on the J offset angle values corresponding to each layer of isolines, the carbon fiber printing paths corresponding to the J layers of carbon fiber winding layers can be effectively determined, such that the carbon fiber reinforced layer obtained by three-dimensional printing according to the carbon fiber printing paths of the multi-layer carbon fiber winding layer can greatly improve the bearing capacity of the matrix, and can make the printing efficiency of three-dimensional printing higher and save more carbon fiber materials.

[0019] Other features and aspects of the present disclosure will become apparent from the following detailed description of exemplary embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings included in and constituting a part of this specification, together with the specification, illustrate exemplary embodiments, features, and aspects of the present disclosure and are used to explain the principles of the present disclosure.

[0021] Figure 1 FIG. shows a flowchart of a three-dimensional printing path planning method for a carbon fiber reinforced matrix according to an embodiment of the present disclosure.

[0022] Figure 2 FIG. shows a schematic diagram of a three-dimensional model of a matrix according to an embodiment of the present disclosure.

[0023] Figure 3 FIG. shows a schematic diagram of five load actions according to an embodiment of the present disclosure.

[0024] Figure 4 FIG. shows a schematic diagram of the unit stress vector field under five load actions according to an embodiment of the present disclosure.

[0025] Figure 5 FIG. shows a schematic diagram of the distribution of a multi-layer isoline according to an embodiment of the present disclosure.

[0026] Figure 6a and Figure 6b FIG. shows a schematic diagram of the distribution of equally spaced points according to an embodiment of the present disclosure.

[0027] Figure 7 FIG. shows a schematic diagram of the stress vectors corresponding to each equally spaced point on a local isoline according to an embodiment of the present disclosure.

[0028] Figure 8A schematic diagram showing four offset angle values corresponding to each contour line in a local contour line according to an embodiment of the present disclosure.

[0029] Figure 9 A schematic diagram showing a local carbon fiber printing path of a certain carbon fiber winding layer according to an embodiment of the present disclosure.

[0030] Figure 10 A schematic diagram showing carbon fiber printing paths corresponding to four carbon fiber winding layers according to an embodiment of the present disclosure.

[0031] Figure 11 A schematic diagram showing the result of three-dimensional printing path planning according to an embodiment of the present disclosure.

[0032] Figure 12 A schematic diagram showing a three-dimensional printing system based on a carbon fiber reinforced matrix according to an embodiment of the present disclosure.

[0033] Figure 13 A schematic diagram showing a kind of matrix fixing frame according to an embodiment of the present disclosure.

[0034] Figure 14 A schematic diagram showing a simulation of a three-dimensional printing process according to an embodiment of the present disclosure.

[0035] Figure 15 A block diagram showing an electronic device 1900 according to an embodiment of the present disclosure. Detailed Description of Specific Embodiments

[0036] Various exemplary embodiments, features, and aspects of the present disclosure will be described in detail below with reference to the accompanying drawings. The same reference numerals in the drawings denote elements having the same or similar functions. Although various aspects of the embodiments are shown in the drawings, the drawings do not have to be drawn to scale unless otherwise specified.

[0037] The special term "exemplary" herein means "serving as an example, embodiment, or illustration". Any embodiment described as "exemplary" herein does not have to be construed as superior to or better than other embodiments.

[0038] The term "and / or" herein merely describes the associated relationship of associated objects and indicates that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the term "at least one" herein means any one of a plurality or any combination of at least two of a plurality. For example, including at least one of A, B, and C can represent including any one or more elements selected from the set composed of A, B, and C. In the description of the present disclosure, "a plurality" means two or more unless otherwise specifically defined.

[0039] It should be understood that the terms "first", "second", etc. in the claims, the description and the drawings of the present disclosure are used to distinguish different objects, rather than to describe a specific order. The terms "comprising" and "including" used in the description and claims of the present disclosure indicate the presence of the described features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or their combinations.

[0040] In addition, for a better illustration of the present disclosure, numerous specific details are given in the following detailed implementation manners. Those skilled in the art should understand that the present disclosure can also be implemented without some specific details. In some instances, methods, means, elements and circuits well-known to those skilled in the art are not described in detail so as to highlight the gist of the present disclosure.

[0041] To give full play to the advantages of continuous carbon fiber in structural reinforcement, the embodiments of the present disclosure propose a three-dimensional printing path planning method, a three-dimensional printing method and a three-dimensional printing system based on carbon fiber reinforced matrix, which can combine a digital model and finite element analysis to calculate the optimal carbon fiber printing path, and through the collaborative work of a multi-axis robotic arm and a dedicated carbon fiber extrusion head, precisely print a thermoplastic carbon fiber reinforced layer on the matrix. This solution significantly improves the printing efficiency and reinforcement effect, can accurately reinforce the stress area of the matrix, not only improves the utilization efficiency and uniform distribution of carbon fiber, but also significantly enhances the strength and durability of the matrix structure. With the cooperation of two six-axis robotic arms (a total of 12 axes) and a customized carbon fiber extrusion head, continuous carbon fiber can be precisely wound on the matrix, providing a new solution for the manufacture of high-performance structures. Further, this solution can meet the mechanical property requirements of different industries and application fields through specific model calculations, and is particularly suitable for rapidly developing high-tech fields such as robots, drones and robotic arms. With its efficient path planning, precise reinforcement effect and wide applicability, this technology has important industrial application value. With the continuous maturity of the technology and the increasing market demand, it is expected that this technology will be widely applied in multiple fields such as aerospace, automotive, and robotics, and become an important driving force for the technological upgrading and innovative development of related industries.

[0042] The three-dimensional printing path planning method, the three-dimensional printing method and the three-dimensional printing system based on carbon fiber reinforced matrix proposed by the embodiments of the present disclosure are particularly suitable for the secondary reinforcement of existing matrices, especially for matrices with the same cross-sectional shape and the same cross-sectional area between both ends, such as cylinders, square cylinders, circular tubes, square tubes, etc. These matrices can be in any shape such as L-shaped, S-shaped, etc., but the cross-sectional shape and cross-sectional area of each part of the matrix are the same. It can achieve precise printing of continuous carbon fiber reinforced layers on the matrix, thereby significantly enhancing the strength and durability of the matrix while reducing the manufacturing cost.

[0043] The 3D printing path planning method, 3D printing method, and 3D printing system based on a carbon fiber reinforced matrix proposed in the embodiments of the present disclosure combine digital design and precise path control to achieve efficient carbon fiber reinforced printing. First, a finite element analysis is performed on the 3D model to evaluate the stress distribution and identify areas with concentrated stress. According to the stress analysis results, multi-layer contour lines are generated, and the joints and curves of the contour lines are optimized to determine the 3D printing path planning scheme for the matrix. In terms of equipment, a 3D printing system with dual robotic arms is constructed. By synchronously controlling the two robotic arms, the precise execution of the path planning is ensured, effectively improving the accuracy and consistency of the carbon fiber reinforced layer, and providing an innovative solution for the manufacture of high-performance structures.

[0044] The 3D printing path planning method, 3D printing method, and 3D printing system based on a carbon fiber reinforced matrix proposed in the embodiments of the present disclosure are introduced in detail below.

[0045] Figure 1 The flowchart of a 3D printing path planning method based on a carbon fiber reinforced matrix according to an embodiment of the present disclosure is shown. As Figure 1 shown, the method includes: step S11 to step S16.

[0046] In step S11, by performing a finite element analysis on the 3D model of the matrix to be reinforced, a stress vector set corresponding to the matrix is obtained. The stress vector set characterizes the distribution of the stress vectors received by the matrix under each of the M kinds of loadings, where M is a positive integer.

[0047] In practical applications, the matrix can be any solid structure on which a carbon fiber reinforced layer is to be printed on the surface. Optionally, the matrix can include a matrix with the same cross-sectional shape and cross-sectional area between both ends, such as, a cylinder, a square cylinder, a circular cylinder, a square column, a circular tube, a square tube, etc. These matrices can be of any shape such as L-shaped, S-shaped, etc. The embodiments of the present disclosure do not limit the shape, size, material, etc. of the matrix.

[0048] Among them, the 3D model of the matrix can be constructed by known 3D model construction techniques in the art. For example, the 3D model of the matrix can be drawn using 3D model drawing software, or the matrix can also be 3D scanned using a 3D scanning device to obtain the 3D model of the matrix. The embodiments of the present disclosure do not limit this.

[0049] Among them, finite element analysis software known in the art can be used to implement finite element analysis of the three-dimensional model of the substrate. When performing finite element analysis on the three-dimensional model, corresponding loads can be applied to the three-dimensional model (that is, a certain force or torque is applied) to obtain the distribution of stress vectors to which the substrate is subjected under the load. It should be understood that the embodiments of the present disclosure do not limit the number and types of loads, and can be customized based on the load scenarios that the substrate may be subjected to in actual scenarios, and the embodiments of the present disclosure do not limit this.

[0050] For example, for Figure 2 A three-dimensional model of a substrate is shown. The three-dimensional model can be imported into the finite element analysis software, and specific material properties can be set for the three-dimensional model of the substrate in the software (for example, the material properties can be set to short-cut carbon fiber composite material Nylon12-CF). Then, the edge surface of the three-dimensional model can be defined, and the load scenario (such as torsion, end bearing, etc.) can be designed. The load constraint surface and the applied force and moment are also clarified, that is, multiple load effects can be set for the three-dimensional model of the substrate. For example, it can be defined Figure 2 The edge faces of the three-dimensional model shown are face A and face B, and the design is as follows Figure 3 There are five load actions involving joint torsion and end bearing as shown in (1) to (5), among which, Figure 3 (1) in the equation represents constraining surface B, applying a downward force F at the center point of surface A, for example, F = 20N; Figure 3 (2) in the equation represents the constraint on surface B. A moment M perpendicular to surface A and directed outward is applied to the center point of surface A. For example, M = 2000 N·m. Figure 3 (3) in the equation represents the constraint on surface A. A moment M perpendicular to surface B is applied outward at the center point of surface B, for example, M = 2000 N·m. Figure 3 (4) in the equation represents the constraint on surface B, which applies a moment -M perpendicular to surface A and inward at the center point of surface A, for example, M = 2000 N·m; Figure 3 (5) in the figure represents the constraint on surface A. A moment -M perpendicular to surface B is applied to the center point of surface B, for example, M = 2000 N·m. Then, the finite element analysis software is used to perform finite element analysis on the three-dimensional model of the substrate based on the above five loads, and the following can be obtained: Figure 4 (1) to (5) are Figure 3 The unit stress vector field under each of the five loads (1) to (5) in the above equations is obtained, and thus the set of stress vectors acting on the discrete points of the matrix is ​​obtained. This set of stress vectors can characterize the distribution of the stress vectors acting on the matrix under each of the five loads mentioned above. It should be understood that if this set of stress vectors is known, the stress vector acting on any point on the surface of the matrix can be known, and specifically, it can be the unit stress vector.

[0051] In step S12, multiple layers of contour lines corresponding to the outer surface of the three-dimensional model are generated. Each layer of contour lines includes N equally spaced points evenly distributed thereon. There is an association relationship between the equally spaced points on adjacent contour lines among the multiple layers of contour lines. The connection relationship is used to indicate the equally spaced points associated with each other on adjacent contour lines, and N is a positive integer.

[0052] Among them, those skilled in the art can adopt any known contour line generation technology in the art to generate multiple layers of contour lines corresponding to the outer surface of the three-dimensional model, which is equivalent to drawing multiple layers of contour lines on the outer surface of the substrate. For example, multiple layers of contour lines can be generated on the outer surface of the three-dimensional model according to the specified average layer height, and multiple equally spaced points evenly distributed can be generated on each layer of contour lines, that is, the distance between each equally spaced point on the same contour line is the same, and the number of equally spaced points generated on each layer of contour lines is the same.

[0053] Optionally, an embodiment of the present disclosure provides a contour line generation method. Specifically, step S12 of generating multiple layers of contour lines corresponding to the outer surface of the three-dimensional model may include:

[0054] 12.1. Perform triangular meshing on the outer surface corresponding to the three-dimensional model to obtain a three-dimensional mesh model, where the three-dimensional mesh model represents the triangular meshed outer surface;

[0055] 12.2. Determine the distance field corresponding to the three-dimensional model according to the positions of the grid points in the three-dimensional mesh model. The distance field includes the distances from each grid point on the three-dimensional mesh model to the specified surface of the three-dimensional model, and the specified surface includes the edge surfaces at both ends of the three-dimensional model;

[0056] 12.3. Generate multiple layers of contour lines corresponding to the outer surface of the three-dimensional model based on the distance field and the preset average layer height, where the seam positions between the multiple layers of contour lines are aligned and the generation directions are the same;

[0057] 12.4. Extract N equally spaced points evenly distributed on each layer of contour lines according to the preset average distance, and the N equally spaced points extracted on each layer of contour lines are aligned with each other. And determine the equally spaced points aligned with each other on adjacent contour lines among the multiple layers of contour lines as the corresponding associated equally spaced points, so as to obtain the association relationship between the equally spaced points on adjacent contour lines among the multiple layers of contour lines. The average distance represents the distance between two adjacent equally spaced points on the same contour line.

[0058] In step 12.1, the outer surface corresponding to the three-dimensional model is subjected to triangular meshing, which is equivalent to extracting the outer wall surface of the substrate and evenly triangulating it. Those skilled in the art can use any known triangular meshing technology in the art to implement the triangular meshing of the outer surface corresponding to the three-dimensional model, and the embodiments of the present disclosure do not limit this.

[0059] In step 12.2, the positions of the grid points in the three-dimensional grid model (equivalent to the grid points on the substrate surface) can be the three-dimensional coordinates of each grid point. Thus, the distance field can be obtained by calculating the distances from the three-dimensional coordinates of each grid point in the three-dimensional grid model to the edge surfaces at both ends of the three-dimensional model (i.e., the distance from a point to a plane). Specifically, it can be the actual distance calculated by the grid points along the three-dimensional model (i.e., along the substrate surface) to the two edge surfaces, so as to generate a distance field with the two edge surfaces on both sides of the substrate as the upper and lower boundaries based on the triangulated outer surface. Exemplarily, for Figure 2 the three-dimensional model shown in, surface A and surface B can be the edge surfaces at both ends, that is, the actual distances from each grid point on the triangulated outer surface corresponding to this three-dimensional model to surface A and surface B can be calculated (i.e., the distances calculated along the outer surface).

[0060] In step 12.3, given the distances from each grid point on the outer surface of the three-dimensional model (i.e., the outer edge surface of the substrate) to the edge surfaces at both ends of the substrate, and given the preset average layer height (i.e., the distance between adjacent contour lines), the linear interpolation method can be used to generate multiple layers of contour lines based on the average layer height and the distances from each grid point to both ends. It should be understood that the number of generated contour lines depends on the length between both ends of the substrate and the average layer height, and the average layer height can be customarily set, and the embodiments of the present disclosure do not limit this. Exemplarily, assuming the average layer height is h = 4 mm, for Figure 2 the three-dimensional model shown in, Figure 5 the multiple layers of contour lines shown in can be generated. The number of layers L of the contour lines corresponding to this three-dimensional model is 67, that is, 67 layers of contour lines are generated.

[0061] In practical applications, after generating multi-layer contour lines, if the seam positions between the contour lines of each layer are not aligned and / or the generation directions are different, the seam positions and generation directions (i.e., the curve directions of the contour lines) between the contour lines of each layer can also be adjusted so that the seam positions between the contour lines of each layer are aligned and the generation directions are the same. For example, the seam position and generation direction of the first contour line can be used as a reference to adjust the seam positions and generation methods of other contour lines. Of course, the default seam position and generation method can also be used as a reference for adjustment, and the embodiments of the present disclosure do not limit this. Among them, the seam position is also the position where the contour line starts to be drawn back to this point from a certain point. The alignment of the seam positions of the contour lines of each layer means that the seam positions are close (for example, the distance between the seam positions of adjacent contour lines is the shortest), or in other words, the seam positions of the contour lines of each layer are in the same plane; the contour line generation direction is also the drawing direction of the contour line. For example, the contour line may start from a certain point and be drawn clockwise back to this point, or may start from a certain point and be drawn counterclockwise back to this point; by making the seam positions between the contour lines of each layer aligned and the generation directions the same, it is convenient to generate equidistant points that are aligned with each other on each layer of contour lines subsequently.

[0062] In step 12.4, according to a preset average distance, for example, starting from the seam position of each layer of contour lines and following the generation direction of the contour line, N evenly distributed equidistant points can be extracted on each layer of contour lines. It can be understood that since the seam positions between the multi-layer contour lines are aligned and the generation directions are the same, and the average distance between every two equidistant points is the same, the N equidistant points respectively extracted on each layer of contour lines can be aligned with each other. Furthermore, the equidistant points that are aligned with each other on adjacent contour lines in the multi-layer contour lines can be determined as corresponding associated equidistant points, that is, the association relationship between the equidistant points on adjacent contour lines in the multi-layer contour lines is obtained. It should be understood that the number N of equidistant points extracted on each layer of contour lines depends on the preset average distance and the length of the contour line. The average distance can be set customarily. For example, let the average distance be d, and the length of each contour line be , then the number of equidistant points extracted on each layer of contour lines , where represents the sum of the lengths of all contour lines, represents the total number of layers of contour lines. Exemplarily, let the average distance d be 2.5 mm. Based on the multi-layer contour lines shown in Figure 5 , a schematic diagram of the distribution of equidistant points shown in Figure 6a can be generated. As shown in Figure 6a , the N equidistant points respectively divided on adjacent contour lines in the multi-layer contour lines are aligned with each other. Among them, as shown in Figure 6b , the 67 equidistant points distributed along the curve in the figure are aligned with each other, that is, these 67 equidistant points are associated equidistant points. By analogy, N groups of associated equidistant points can be obtained, and the above association relationship can record these N groups of associated equidistant points.

[0063] It should be understood that the contour lines and the generation method of equidistant points on the contour lines provided in the above embodiments of the present disclosure are a possible implementation manner provided by the embodiments of the present disclosure. In fact, those skilled in the art can adopt any known technical means in the art to generate the contour lines as shown in Figure 5 and the equidistant points as shown in Figure 6a , and the embodiments of the present disclosure do not make any restrictions on this.

[0064] In step S13, according to the stress vector set, determine the M stress vectors received by each equidistant point on each contour line. The M stress vectors received by each equidistant point include the stress vectors received by each equidistant point under each of the M loadings.

[0065] As described above, knowing the stress vector set means knowing the stress vectors received by any point on the matrix surface under each loading, so it is also possible to know the stress vectors received by each equidistant point on each contour line under each of the M loadings. Exemplarily, for the unit stress vector fields (i.e., the stress vector set) shown in (1) to (5) in Figure 4 , the stress vectors corresponding to each equidistant point on the local contour line as shown in Figure 7 can be obtained. Figure 7 Each arrow on each equidistant point in Figure 7 indicates the unit stress vector received by the equidistant point under each loading. It should be understood that the unit stress vectors received by the same equidistant point under different loadings may be different or the same. Therefore,

[0066] In step S14, by calculating the angles between the M stress vectors received by each equidistant point on each contour line and the tangent vector of the equidistant point on its own contour line, M angle values corresponding to each equidistant point on each contour line are obtained.

[0067] It can be known that the carbon fiber reinforced layer is printed against the matrix surface. Therefore, by calculating the angle between the stress vector and the tangent vector, it is convenient to subsequently determine the offset angle value for offsetting along the matrix surface, so as to determine an effective carbon fiber printing path. That is, the angle value α0 corresponding to each stress vector of all equidistant points o on each contour line can be calculated, which is the angle of the stress vector in the o- plane, where is the tangent vector of the equidistant point o on its own contour line. is the normal vector of o on the surface. It should be understood that M stress vectors can correspond to M calculated angle values. Given the center and radius of the circle corresponding to the isoline and the positions of equally spaced points on the isoline, the tangent vector of any equally spaced point on the isoline can be calculated. This tangent vector can be the tangent vector along the generation direction of the isoline, and the embodiments of the present disclosure do not limit this. In addition, the embodiments of the present disclosure also do not limit the calculation method of the angle value between two vectors.

[0068] In step S15, according to the M angle values corresponding to each of the N equally spaced points on each layer of isoline, J offset angle values corresponding to each layer of isoline are determined. The J offset angle values correspond to J carbon fiber winding layers, and J is a positive integer.

[0069] It should be understood that the M angle values corresponding to each equally spaced point on the same layer of isoline are different. In order to determine the unified offset angle value for each layer of isoline, that is, to uniformly offset the equally spaced points on each layer of isoline, so as to ensure the uniformity of the arrangement between carbon fiber printing paths. For example, by statistically analyzing the angle values of all equally spaced points on each layer of isoline, J offset angle values that can minimize the coverage of all angle values can be found. This is equivalent to clustering and grouping the N×M angle values on each layer of isoline to obtain J groups of angle values, and the clustering centers of the J groups of angle values can be used as the J offset angle values corresponding to this layer of isoline. Furthermore, the similar offset angle values between adjacent isolines in multiple layers of isolines can be determined as the offset angle values corresponding to the same carbon fiber winding layer. Similar offset angle values can be understood as the angle directions indicated by the offset angle values being close, which is beneficial to making the subsequent determined carbon fiber printing paths continuous and smooth. Of course, the offset angle values corresponding to each carbon fiber winding layer for each layer of isoline can also be custom-set, and the embodiments of the present disclosure do not limit this.

[0070] Considering that the angle values calculated through step S14 may not be the angle values that can wind carbon fiber onto the substrate. For example, when the angle value is 0 degrees, it is impossible to wind onto the substrate. When the N×M angle values on the isoline include the above angle values, the determined offset angle values may be the angle values that cannot wind carbon fiber onto the substrate. Therefore, in order to make the determined offset angle values meet the actual winding requirements (that is, to be able to wind carbon fiber onto the substrate), in a possible implementation manner, the above step S15 of determining J offset angle values corresponding to each layer of isoline according to the M angle values corresponding to each of the N equally spaced points on each layer of isoline may include:

[0071] 15.1. For the N×M angular values on the x-th layer contour line, determine whether each of the N×M angular values is within a preset angular range. In the case where there are angular values among the N×M angular values that do not belong to the preset angular range, correct the angular values that do not belong to the preset angular range to the boundary value closest to the angular value in the preset angular range, so as to obtain the N×M target angular values corresponding to the N equally spaced points on the x-th layer contour line. The preset angular range represents the angular range that enables the carbon fiber to wind around the substrate.

[0072] 15.2. By statistically grouping the N×M target angular values, obtain J angular groups divided by the N×M target angular values within the preset angular range and the central angular value corresponding to each angular group among the J angular groups.

[0073] 15.3. Determine the central angular value corresponding to each of the J angular groups as the J offset angular values corresponding to the x-th layer contour line.

[0074] In step 15.1, the preset angular range is usually related to the shape and size of the substrate. In practical applications, the preset angular range can be set according to historical experience combined with experimental verification. The specific range of the preset angular range in the embodiments of the present disclosure is not limited. For example, for Figure 2 the substrate corresponding to the shown three-dimensional model, the corresponding preset angular range may include [-70°, -20°] ∪ [20°, 70°]. Then -70°, -20°, 20°, and 70° are the boundary values of the preset angular range. When the angular value is not within [-70°, -20°] ∪ [20°, 70°], it can be corrected to the closest boundary value. For example, if the N×M angular values on a certain layer contour line include the angular values 90°, 10°, and -80°, then 90° can be corrected to the boundary value 70° closest to 90°, 10° can be corrected to the boundary value 20° closest to 10°, and -80° can be corrected to the boundary value -70° closest to -80°, so as to obtain the N×M target angular values on this layer contour line. The N×M target angular values then include the corrected 70°, 20°, and -70°.

[0075] In step 15.2, statistical analysis techniques known in the art and the like can be used to perform statistical grouping on N×M target angle values, obtaining J angle groups divided from the N×M target angle values within a preset angle range and the central angle value corresponding to each angle group among the J angle groups. For example, by calculating the distance between every two of the N×M target angle values and grouping the N×M target angle values based on the distances between every two of them, the distances between the angle values within the same angle group are the closest and the distances between the angle values in different angle groups are the farthest. The central angle value of each angle group can be understood as the clustering center of each angle value, so the central angle value corresponding to each angle group can be the angle value with the minimum sum of distances between it and each target angle value within each angle group. Thus, it is possible to minimize the J offset angle values determined by any contour line covering the angle values of all equidistant points on that contour line.

[0076] Considering that the preset angle range can include two opposite angle ranges. For example, the preset angle range [-70°, -20°] ∪ [20°, 70°] includes two opposite angle ranges [-70°, -20°] and [20°, 70°]. Therefore, r angle groups (i.e., 2 / J) can be divided within each angle range, 2r = J. The J offset angle values corresponding to the x-th contour line include the central angle values corresponding to the r angle groups divided from the N×M target angle values within each of the two opposite angle ranges. Among them, those skilled in the art can set the value of J according to historical experience. J can be the number that can minimize the offset angle values covering all angle values. For example, J can be 4 (representing 4 carbon fiber winding layers), that is, the x-th contour line can find 4 offset angle values within the preset angle range. , specifically, 2 negative offset angle values and 2 positive offset angle values can be found respectively within the two opposite angle ranges. Of course, J can be 6 (representing 6 carbon fiber winding layers), which can make the printed carbon fiber reinforced layer more tightly and firmly.

[0077] Exemplarily, based on Figure 7 the five stress vectors corresponding to each equidistant point on the shown partial contour line, performing the above steps S14 to S15 can obtain Figure 8 the four offset angle values corresponding to each contour line in the shown partial contour line, as Figure 8As shown, there are four arrows at equidistant points, respectively representing the offset directions corresponding to four offset angle values. The offset directions indicated by the four arrows at each equidistant point on the same isoline are the same, representing that the four offset angle values corresponding to each equidistant point on the same isoline are the same. Among them, the four offset angle values of each layer of isolines can correspond to four carbon fiber winding layers, and the offset angle values corresponding to each layer of isolines in each carbon fiber winding layer can be determined simultaneously.

[0078] In step S16, according to the J offset angle values corresponding to each layer of isolines in the multi-layer isolines, a carbon fiber printing path corresponding to each of the J carbon fiber winding layers is generated.

[0079] As described above, there is an association relationship between the equidistant points on adjacent isolines in the multi-layer isolines, and the association relationship is used to indicate the mutually associated equidistant points on adjacent isolines; in a possible implementation manner, the above-mentioned generating a carbon fiber printing path corresponding to each of the J carbon fiber winding layers according to the J offset angle values corresponding to each layer of isolines in the multi-layer isolines includes:

[0080] 16.1. For the j-th carbon fiber winding layer among the J carbon fiber winding layers, according to the offset angle value corresponding to each layer of isolines in the j-th carbon fiber winding layer and the average layer height of the multi-layer isolines, the N equidistant points on each layer of isolines are offset to obtain N target equidistant points after offset on each layer of isolines, where 1 ≤ j ≤ J;

[0081] 16.2. According to the association relationship between the equidistant points on adjacent isolines in the multi-layer isolines and the N target equidistant points after offset on each layer of isolines, the target equidistant points associated between adjacent isolines in the multi-layer isolines are connected correspondingly to obtain the carbon fiber printing path corresponding to the j-th carbon fiber winding layer.

[0082] Among them, the above-mentioned for the j-th carbon fiber winding layer among the J carbon fiber winding layers, according to the offset angle value corresponding to each layer of isolines in the j-th carbon fiber winding layer and the average layer height of the multi-layer isolines, offsetting the N equidistant points on each layer of isolines to obtain N target equidistant points after offset on each layer of isolines may include:

[0083] For the x-th layer of isolines of the j-th carbon fiber winding layer among the J carbon fiber winding layers, according to the offset angle value corresponding to the x-th layer of isolines in the j-th carbon fiber winding layer and the average layer height, determine the offset amount of the x-th layer of isolines under the j-th carbon fiber winding layer;

[0084] By accumulating the offset of the contour line of the first layer under the j-th carbon fiber winding layer to the offset of the contour line of the x-th layer under the j-th carbon fiber winding layer, the accumulated offset of the contour line of the x-th layer under the j-th carbon fiber winding layer is obtained;

[0085] According to the accumulated offset of the contour line of the x-th layer under the j-th carbon fiber winding layer, the N equally spaced points on the contour line of the x-th layer are offset along the contour line of the x-th layer by the accumulated offset to obtain N target equally spaced points after offset on the contour line of the x-th layer.

[0086] Among them, the offset of the contour line of the x-th layer under the j-th carbon fiber winding layer can be expressed as: , represents the average layer height, represents the offset angle value corresponding to the contour line of the x-th layer under the j-th carbon fiber winding layer; similarly, in step 16.2, the offset of the contour line of the first layer under the j-th carbon fiber winding layer can be expressed as , represents the offset angle value corresponding to the contour line of the first layer under the j-th carbon fiber winding layer. Furthermore, the accumulated offset of the contour line of the x-th layer under the j-th carbon fiber winding layer is expressed as , where the accumulated offset of the contour line of the first layer under the j-th carbon fiber winding layer is also the offset of the contour line of the first layer under the j-th carbon fiber winding layer. Then, in step 16.3, each equally spaced point on the contour line of the x-th layer of the j-th carbon fiber winding layer is offset along the contour line , so that the deflection angle of the offset carbon fiber printing path and the offset angle value are similar, which is beneficial to generating an effective and evenly arranged carbon fiber printing path subsequently.

[0087] As described above, when generating equally spaced points on each layer of contour lines through the above step S12, the equally spaced points related to each other on adjacent contour lines in multiple layers of contour lines (i.e., the above-mentioned correlation relationship) can be recorded. After offsetting the N equally spaced points on each layer of contour lines, the equally spaced points between adjacent contour lines are usually no longer aligned in position, but still connect the target equally spaced points related to each other between adjacent contour lines in multiple layers of contour lines (i.e., the equally spaced points that are not aligned but related, or the offset related equally spaced points) according to the above-mentioned correlation relationship to obtain the carbon fiber printing path corresponding to the j-th carbon fiber winding layer. It should be understood that if there are N equally spaced points on the contour line, N curves (i.e., N carbon fiber printing paths) can be connected. Exemplarily, based on Figure 8 the offset angle value of a certain layer of carbon fiber winding layer on the local contour line shown in, by executing the above steps 16.1 to 16.2, the local carbon fiber printing path of this carbon fiber winding layer as shown in Figure 9 can be generated.

[0088] Considering that the carbon fiber printing path obtained by correspondingly connecting the target equidistant points between adjacent isopleths in multiple layers of isopleths may not be smooth enough. To make the carbon fiber printing path smoother, the connection lines between the target equidistant points on multiple layers of isopleths can also be softened. Thus, in a possible implementation manner, the above-mentioned method of correspondingly connecting the target equidistant points associated between adjacent isopleths in multiple layers of isopleths according to the association relationship between the equidistant points on adjacent isopleths in multiple layers of isopleths and the N target equidistant points offset on each layer of isopleth to obtain the carbon fiber printing path corresponding to the j-th carbon fiber winding layer may include:

[0089] According to the association relationship between the equidistant points on adjacent isopleths in multiple layers of isopleths and the N target equidistant points offset on each layer of isopleth, correspondingly connect the target equidistant points associated between adjacent isopleths in multiple layers of isopleths, and soften the connection result to obtain the carbon fiber printing path corresponding to the j-th carbon fiber winding layer. Among them, those skilled in the art can adopt the known softening processing methods in the art. For example, a spline curve can be generated based on multiple mutually associated target equidistant points on multiple layers of isopleths, and then the positions of each target equidistant point on the spline curve are projected onto the surface of the three-dimensional model, so that the printing path obtained after connecting the target equidistant points is smoother. Or, the position of the target equidistant point with a prominent position among multiple mutually associated target equidistant points can also be corrected to the average value of the positions of multiple target equidistant points. The embodiments of the present disclosure do not limit this.

[0090] It should be understood that for each carbon fiber winding layer among the J carbon fiber winding layers, the carbon fiber printing path corresponding to each carbon fiber winding layer can be obtained according to the above steps 16.1 to 16.2. Exemplarily, for Figure 2 the shown three-dimensional model of the substrate, the carbon fiber printing paths corresponding to the four carbon fiber winding layers shown in (1) to (4) in Figure 10 can be generated.

[0091] Among them, the three-dimensional printing path planning result corresponding to the substrate may include the carbon fiber printing paths corresponding to the J carbon fiber winding layers. For example, Figure 11 the shown three-dimensional printing path planning result may include Figure 10 the carbon fiber printing paths corresponding to the four carbon fiber winding layers shown in (1) to (4) in

[0092] In practical applications, given the three-dimensional printing path planning result corresponding to the known substrate, any known three-dimensional printing system in the art can be controlled to perform the printing work of printing a carbon fiber reinforced layer on the substrate according to the above three-dimensional printing path planning result. For example, each carbon fiber winding layer can be printed in sequence according to the carbon fiber printing path of each carbon fiber winding layer, so as to realize the printing of a carbon fiber reinforced layer on the substrate. The embodiments of the present disclosure do not limit this. Among them, the carbon fiber involved in the embodiments of the present disclosure can be continuous carbon fiber, which can form carbon fiber filaments to generate a carbon fiber reinforced layer.

[0093] According to the path planning method of the embodiments of the present disclosure, obtaining the stress vector set by performing finite element analysis on the three-dimensional model of the substrate is equivalent to obtaining the stress distribution of the substrate under various loadings. Furthermore, based on the stress distribution, the offset angle values of equally spaced points on the isocontour are determined, which can make the offset angle values of each equally spaced point on each isocontour uniform. This is beneficial to ensuring that the arrangement of the printing paths in each carbon fiber winding layer is relatively uniform and covers the stress distributions in multiple directions of the substrate. Then, based on the J offset angle values corresponding to each layer of isocontour, the three-dimensional carbon fiber printing paths corresponding to the J layers of carbon fiber winding layers can be effectively determined. Making the carbon fiber reinforced layer obtained by three-dimensional printing according to the carbon fiber printing paths of multiple carbon fiber winding layers can greatly improve the bearing capacity of the substrate, and can make the printing efficiency of three-dimensional printing higher and save more carbon fiber materials.

[0094] The embodiments of the present disclosure also propose a Figure 12 Three-dimensional printing system based on a carbon fiber reinforced substrate, as Figure 12 shown. The system mainly includes a main robotic arm 01, an auxiliary robotic arm 02, a carbon fiber print head 03, and a substrate fixing frame 04. Among them, the carbon fiber print head 03 is installed on the auxiliary robotic arm 02, the substrate fixing frame 04 is installed on the main robotic arm 01, the carbon fiber print head 03 is used to generate carbon fiber filaments, and the substrate fixing frame 04 is used to fix the substrate to be reinforced (such as 00 in the figure).

[0095] It should be understood that those skilled in the art can use known robotic arms in the art as the main robotic arm 01 and the auxiliary robotic arm 02. For example, the main robotic arm 01 can use a KUKA KR6 R700 6-axis industrial robot to drive the substrate fixed on the substrate fixing frame 04; the auxiliary robotic arm 02 can use a KUKA Agilus KR6-10 R900 6-axis industrial robot to drive the carbon fiber print head 03. The dual robotic arm installation process may include: fixing the dual robotic arms at a predetermined position, connecting cables to the control cabinet, configuring power supply and network, installing KUKA software and completing initial settings to ensure normal operation of the system; and then performing base coordinate calibration, that is, adjusting the zero position and direction of the base coordinate system of the two robotic arms in turn through the teach pendant to verify the alignment accuracy of the coordinate systems of the two robotic arms.

[0096] In practical applications, those skilled in the art can customize the design of the specific structure of the carbon fiber print head 03 and the substrate fixing frame 04. Of course, the carbon fiber print head 03 and the substrate fixing frame 04 known in the art can also be used, as long as they can achieve the functions required to be achieved, and the embodiments of the present disclosure are not limited to this. Among them, the carbon fiber print head 03 can be understood as a tool head for extruding continuous carbon fiber prepreg filaments installed on the auxiliary robot arm.

[0097] The substrate fixing frame 04 may include a winding frame and auxiliary connecting parts for fixing the substrate to facilitate accurate operation of the winding process. Figure 13 A substrate fixing frame is shown, which may include wire collection extension pieces (041 and 042) at both ends and a flange connection piece 043; wherein the wire collection extension piece is used to assist the carbon fiber print head in pulling out the carbon fiber filaments (such as Figure 14 As shown in (a) in the beginning stage of printing, the carbon fiber filaments are pulled out from the print head and tied to the wire collection extension member), that is, at the beginning stage of winding, one end of the carbon fiber filaments needs to be pulled out from the print head and tied to the wire collection extension member so that the filament winding process can be stably pulled out; and Figure 14 As shown in (b) in the figure, the filament collection extension piece is also used to wind the carbon fiber filaments produced by the carbon fiber print head during the resetting of the main robot arm, that is, to receive the winding of continuous fibers when the main robot arm is reset (for example, when the printing path exceeds the corner limit of the main robot arm and is reset). Figure 13As shown, the wire gathering and stretching member 041 is fixedly connected to the base body 00. One end of the wire gathering and stretching member 042 is fixed to the base body 00 and the other end is connected to the flange connecting member 043. The flange connecting member 043 is connected to the main robotic arm 01. That is to say, the flange connecting member 043 is used to connect the wire gathering and stretching member at one end of the base fixing frame to the flange at the end of the main robotic arm, so as to fix the base fixing frame 04 with the base body 00 fixed thereon to the main robotic arm 01. Among them, in the embodiment of the present disclosure, the fixing manner of the wire gathering and stretching member 041 on the base body is not limited, and the flange connecting member 043 can adopt a standardized interface to ensure reliable cooperation with the end of the robotic arm.

[0098] In practical applications, as Figure 13 shown, some anchor points can also be provided at both the head and tail ends of the base body 00 (i.e., the anchor points indicated by the triangular patterns at both ends), which are used to fix the carbon fiber filaments and ensure that the carbon fiber filaments can be stably drawn out. Or rather, it can help ensure that the starting position of the carbon fiber filaments is fixed and the filaments are hooked and drawn out. As Figure 14 shown in (c) of, the carbon fiber filaments are hooked by the anchor points at both ends of the base body to ensure that the carbon fiber filaments are drawn out and covered onto the base body along the carbon fiber printing path.

[0099] In practical applications, the assembly and installation process of the base fixing frame 04 can include: assembling the base fixing frame 04 and other accessory connecting members according to the design scheme; enabling the teach pendant and switching to the T1 mode, selecting the main robotic arm for manual control, adjusting the posture of the main robotic arm to zero the A6 axis, and fixing the base fixing frame 04 to the flange at the end of the main robotic arm with a specified initial pose (for example, with the initial pose that the bend angle of the base body fixed by the base fixing frame 04 faces downward).

[0100] In practical applications, the installation process of the carbon fiber print head 03 can include: switching to the main robotic arm through the teach pendant, adjusting the posture of the main robotic arm to zero its A6 axis, installing the base fixing frame 04 with the base body fixed thereon to the end of the main robotic arm, installing the carbon fiber print head 03 on the auxiliary robotic arm, and adjusting the direction of the carbon fiber print head 03 to face downward as much as possible for subsequent winding operations.

[0101] In practical applications, the measurement and calibration process of the carbon fiber print head 03 may include: using a robotic arm teach pendant, precisely calibrating the TCP (Tool Center Point, TCP, tip point) of the carbon fiber print head 03 through the XYZ four-point method to ensure that its actual position is exactly the same as the theoretical model. Specifically, use the teach pendant to select "Tool Head / Base Coordinate Management" and add a tool head (i.e., the carbon fiber print head 03) to the auxiliary robotic arm. Select the XYZ four-point method in the "Measurement" option, align the tool head with the reference point from four directions in sequence and save the measurement point data. Fine-tune the TCP position of the tool head according to the measurement results to ensure that the actual position of the tool head is consistent with the theoretical model. Save the calibrated tool head information to the controller of the auxiliary robotic arm to provide accurate reference data for subsequent path planning.

[0102] Based on the three-dimensional printing path planning method and the three-dimensional printing system provided by the above embodiments of the present disclosure, the embodiments of the present disclosure also provide a three-dimensional printing method. This printing method is applied to the above three-dimensional printing system, and this printing method includes:

[0103] 2.1. Adopt the above three-dimensional printing path planning method to determine the three-dimensional printing path planning result corresponding to the substrate. This three-dimensional printing path planning result includes the carbon fiber printing paths corresponding to each carbon fiber winding layer in the J carbon fiber winding layers;

[0104] 2.2. According to the three-dimensional printing path planning result, determine the motion instructions of the main robotic arm and the auxiliary robotic arm during the printing process respectively;

[0105] 2.3. Based on the motion instructions of the main robotic arm and the auxiliary robotic arm during the printing process respectively, control the three-dimensional printing system to perform the printing work of the carbon fiber reinforced layer on the substrate.

[0106] It should be understood that step 2.1 can adopt the implementation manners of the above steps S11 to S16 to determine the three-dimensional printing path planning result corresponding to the substrate, which will not be elaborated here.

[0107] As described above, before the main robotic arm 01, the auxiliary robotic arm 02, the carbon fiber print head 03, and the substrate fixing frame 04 fixed with the substrate perform the printing work, installation, calibration, positioning and other work can be carried out, which is equivalent to knowing the robotic arm information (i.e., the models of the two robotic arms), the base coordinate information (i.e., the relative poses of the two robotic arms), the tool head information (i.e., the TCP position of the carbon fiber print head 03 after calibration, etc.), and the initial pose of the substrate. Furthermore, based on the above known information and according to the three-dimensional printing path planning result, the pose data of the main robotic arm and the auxiliary robotic arm during the printing process can be determined, or the motion poses of the main robotic arm and the auxiliary robotic arm during the three-dimensional printing process according to the three-dimensional printing path planning result can be determined.

[0108] The embodiments of the present disclosure do not limit the derivation process of the motion poses of the main robotic arm and the auxiliary robotic arm. For example, those skilled in the art can use any known algorithms or software in the art to determine the respective motion poses of the main robotic arm and the auxiliary robotic arm during printing according to the three-dimensional printing path planning result, and then generate motion instructions. For example, the Grasshopper plugin KUKA-PRC can be used to complete the simulated motion of the two robotic arms based on the three-dimensional printing path planning result and output motion instructions. That is, the above-mentioned robotic arm information, base coordinate information, tool head information, and three-dimensional printing path planning result can be combined to simulate the motion process of the two robotic arms during three-dimensional printing according to the three-dimensional printing path planning result, so as to obtain the respective motion postures of the main robotic arm and the auxiliary robotic arm during printing, and then generate motion instructions. The motion instructions can be used to control the motion pose of the robotic arm during printing.

[0109] As described above, the substrate may include a substrate with the same cross-sectional shape and the same cross-sectional area between both ends; this type of substrate can be regarded as a cylinder, and the initial pose of the main robotic arm can be controlled so that the substrate is in a flat-down state (such as the state shown in (a) in Figure 14 ), that is, the substrate fixed to the substrate fixing frame can be in a flat-down state, and then the motion poses of the two robotic arms can be deduced according to the rotation angle of the substrate, so as to generate motion instructions. Thus, in a possible implementation manner, in the above step 2.1, determining the respective motion instructions of the main robotic arm and the auxiliary robotic arm during printing according to the three-dimensional printing path planning result may include:

[0110] According to the three-dimensional printing path planning result, determine the substrate rotation data corresponding to each carbon fiber printing path in each carbon fiber winding layer, where the substrate rotation data includes the rotation angle of the substrate during the printing process when the carbon fiber printing head prints according to each carbon fiber printing path;

[0111] According to the substrate rotation data corresponding to each carbon fiber printing path in each carbon fiber winding layer, determine the respective motion instructions of the main robotic arm and the auxiliary robotic arm during printing.

[0112] It should be understood that knowing the three-dimensional printing path planning result is equivalent to knowing each carbon fiber printing path (i.e., each connection line) in each carbon fiber winding layer. For the y-th carbon fiber printing path (i.e., the y-th connection line) in the j-th carbon fiber winding layer, the offset angle of the equidistant point corresponding to the y-th carbon fiber printing path on the x-th contour line, that is , and the cumulative angle, that is , the accumulated offset angle represents the rotation angle that the substrate needs to rotate when the carbon fiber filament is wound at each isometric line position, that is, it represents the rotation angle of the A6 axis of the main robotic arm. Thus, the rotation angle of the substrate during the printing process by the carbon fiber print head along each carbon fiber printing path can be obtained. Furthermore, the accumulated angle can be mapped to the A6 axis of the main robotic arm, and all poses of the main robotic arm can be determined based on the specified spatial coordinate system. Then, according to the plane where the main robotic arm is located corresponding to the substrate fixed frame, the points that the carbon fiber long print head reaches accordingly and the plane where the corresponding auxiliary robotic arm reaches can be obtained. The normal vector of the plane direction where the auxiliary robotic arm reaches is determined by the normal vector of the point where the carbon fiber long print head reaches on the substrate surface, and the positive x direction (i.e., the print head orientation) is obtained from the relative positions of the two robotic arms. During this process, the plane position where the main robotic arm reaches can be adjusted to relatively obtain the plane where the auxiliary robotic arm reaches, which is equivalent to knowing the motion poses of the main robotic arm and the auxiliary robotic arm during the printing process. Furthermore, corresponding motion instructions can be generated.

[0113] Among them, in order to ensure the continuity of the carbon fiber filament nearby during the printing process, for every other carbon fiber printing path, the order of the equally spaced points corresponding to the carbon fiber printing path on the isometric line and the accumulated angle will be reversed, which makes the carbon fiber filament arranged in a zigzag reciprocating pattern during the printing process. That is, in order to ensure the continuity of the fiber winding path, for every other fiber, the order of the corresponding points and the accumulated angle will be adjusted in the reverse direction. In this way, the winding path of the carbon fiber filament during the printing process will show a zigzag reciprocating arrangement.

[0114] Among them, considering the possible angular limit of the A6 axis of the robotic arm, the accumulated angle distribution corresponding to each equally spaced point of each carbon fiber printing path can be adjusted to the angular range (-350°, 350°) that the A6 axis of the robotic arm can rotate. If the accumulated angle exceeds this range, the entire carbon fiber printing path can be offset as a whole with a period of 360 degrees (that is, offset by a 360-degree period as a whole) until the accumulated angle falls within the above range. This means that the main robotic arm will drive the substrate to rotate one week to reset. So as shown in (b) of Figure 14 , the carbon fiber print head needs to be kept above both ends (such as the wire gathering elongation part) so that the continuous carbon fiber filament can be wound on it during the reset period. Of course, if there is no angular limit for the main robotic arm, the above reset operation does not need to be performed.

[0115] In practical applications, in the KUKA|prc plugin, the Synchronize Robots component of ROBOTEAM can be used to add the "Sync MOVE" command to the main robotic arm and the auxiliary robotic arm one by one corresponding to each motion command, so that the two robotic arms move synchronously at each point, that is, synchronize the motion commands of the main robotic arm and the auxiliary robotic arm to ensure that the motions of the two robotic arms are consistent at each point. Among them, in the "KUKA|prc CORE" component, information about the robotic arm, base coordinate information, tool head information, the aforementioned command data (that is, the motion instructions of the two robotic arms), the initial speed of the robotic arm (for example, it can be set to 0.25 m / s), project name and save path, etc. can be input respectively, and motion simulation (that is, the planning simulation of the printing path) can be carried out in the ROBOTEAM mode to generate the motion poses of the two robotic arms during the printing process; it should be understood that by applying the above motion simulation method to each layer of the carbon fiber winding layer, the simulation of the overall path planning can be completed, that is, the motion poses of the two robotic arms during the entire printing process are simulated, thereby generating motion instructions. Exemplarily, as Figure 14 the motion simulation achieved in (c) to (f) of Figure 14 in (c) can represent the printing process of the first carbon fiber winding layer of the simulation, Figure 14 in (d) can represent the printing process of the second carbon fiber winding layer of the simulation, Figure 14 in (e) can represent the printing process of the third carbon fiber winding layer of the simulation, Figure 14 in (d) can represent the completion of the printing process of the fourth carbon fiber winding layer of the simulation, and by simulating the printing processes of the above-mentioned individual carbon fiber winding layers, the corresponding motion codes (that is, motion instructions) can be exported.

[0116] In practical applications, after obtaining the motion instructions of the two robotic arms, the motion instruction file can be input into the controllers of the two robotic arms. For example, a USB flash drive carrying the motion instruction file can be inserted into the USB interface of the robotic arm controller, and in the "Administrator Mode", the motion instruction files of the two robotic arms can be copied to the corresponding robotic arm controllers respectively. Select the motion instruction files required by the two robotic arms in sequence in the interactive interface of the robotic arm to prepare for subsequent operations.

[0117] Thus, in the above three-dimensional printing system, the controller in the main robotic arm 01 is used to control the motion posture of the main robotic arm during the printing process according to the motion instructions of the main robotic arm determined by the above printing method; the controller in the auxiliary robotic arm 02 is used to control the motion posture of the auxiliary robotic arm during the printing process according to the motion instructions of the auxiliary robotic arm determined by the above printing method. Thus, the printing work of printing the carbon fiber reinforced layer on the substrate is realized by using the three-dimensional printing system.

[0118] In practical applications, according to the stability requirements of 3D printing, the speed at which the carbon fiber print head produces carbon fiber filaments can also be adjusted, and the moving speeds of the two robotic arms can be adjusted. For example, the ratio of the moving speeds of the two robotic arms can be set to 10% to ensure the accuracy and stability of the printing process. The teach pendant can also be used to move the two robotic arms to a safe position in T1 mode. After switching to Auto mode, the movements of the two robotic arms are adjusted separately to make them reach the BCO position (that is, to make the actual positions of the robotic arms exactly the same as the set positions), so as to prepare for positioning for the printing work.

[0119] Among them, before printing starts, the carbon fiber filament can be pulled out from the carbon fiber print head first and fixed on a nearby wire collecting and elongating part to ensure the smooth extrusion and precise winding of the carbon fiber in the filament during the printing process. Then, the carbon fiber print head can be started, and at the same time, the movements of the two robotic arms are started, so that the two robotic arms gradually print continuous carbon fiber reinforced layers along the surface of the substrate synchronously. After the printing of the carbon fiber reinforced layer is completed, post-treatment can also be performed on the printed carbon fiber reinforced layer, such as surface grinding, polishing, painting, etc., which are not limited in the embodiments of the present disclosure.

[0120] According to the 3D printing method of the embodiments of the present disclosure, the carbon fiber reinforced layer obtained by 3D printing according to the carbon fiber printing path of the multi-layer carbon fiber winding layer can greatly improve the bearing capacity of the substrate, and can make the printing efficiency of 3D printing higher and save more carbon fiber materials.

[0121] It should be noted that the above-mentioned 3D path planning method and 3D printing method proposed in the embodiments of the present disclosure can be deployed on various terminal devices through software or hardware transformation. The terminal devices involved in the embodiments of the present disclosure may refer to devices with wireless connection functions and / or wired connection functions. The wireless connection function means that it can be connected to other devices through wireless connection methods such as wifi and Bluetooth. The terminal devices involved in the embodiments of the present disclosure can also communicate with other devices through the wired connection function. The terminal devices involved in the embodiments of the present disclosure can be touch-screen, non-touch-screen, or without a screen. Touch-screen devices can be controlled by clicking, swiping, etc. on the display screen with fingers, styluses, etc. Non-touch-screen devices can be connected to input devices such as mice, keyboards, and touch panels to control the terminal devices through the input devices. Devices without a screen can be, for example, Bluetooth speakers without a screen. For example, the terminal devices of the present application may include, but are not limited to, user equipment (UE), mobile devices, mobile terminals, handheld devices, tablet computers, laptop computers, palmtop computers, computing devices, etc.

[0122] The above-mentioned three-dimensional path planning method and three-dimensional printing method of the embodiments of the present disclosure can also be deployed on a server, on which a rendering engine can be deployed. The server can be located in the cloud or locally, and can be a physical device or a virtual device, such as a virtual machine, a container, etc., and has a wireless communication function. Among them, the wireless communication function can be set in the chip (system) or other components or assemblies of the server. It can refer to a device with a wireless connection function, and the function of the wireless connection means that it can be connected to other servers or terminal devices through wireless connection methods such as Wi-Fi and Bluetooth. The server involved in the embodiments of the present disclosure can also have a function of communicating through a wired connection. For example, the server of the embodiments of the present disclosure can be located in the cloud, communicate with a terminal device, receive a three-dimensional model of a substrate sent by the terminal device, and use the three-dimensional path printing method deployed on the server to determine a three-dimensional printing path planning result corresponding to the substrate based on the above three-dimensional model, and return it to the terminal device, so as to use the three-dimensional printing method deployed on the terminal device to control the three-dimensional printing system to perform the printing work of the carbon fiber reinforced layer on the substrate based on the three-dimensional printing path planning result corresponding to the substrate.

[0123] Based on the three-dimensional printing path planning method provided by the above embodiments of the present disclosure, the embodiments of the present disclosure further provide a three-dimensional printing path planning device, which may include:

[0124] A finite element analysis module, configured to obtain a stress vector set corresponding to the substrate by performing finite element analysis on a three-dimensional model of the substrate to be reinforced, where the stress vector set represents the distribution of stress vectors received by the substrate under each of the M kinds of loadings;

[0125] An isoline generation module, configured to generate multiple layers of isolines corresponding to the outer surface of the three-dimensional model, and each layer of isolines includes N equally spaced points evenly distributed;

[0126] A stress analysis module, configured to determine M stress vectors received by each equally spaced point on each layer of isolines according to the stress vector set, and the M stress vectors received by each equally spaced point include the stress vectors received by each equally spaced point under each of the M kinds of loadings;

[0127] An angle calculation module, configured to obtain M angle values corresponding to each equally spaced point on each layer of isolines by calculating the angles between the M stress vectors received by each equally spaced point on each layer of isolines and the tangent vector of each equally spaced point on the isoline to which it belongs;

[0128] An offset determination module, configured to determine J offset angle values corresponding to each layer of isolines according to the M angle values corresponding to each of the N equally spaced points on each layer of isolines, and the J offset angle values correspond to J carbon fiber winding layers;

[0129] A path generation module, configured to generate a carbon fiber printing path corresponding to each of the J carbon fiber winding layers according to the J offset angle values corresponding to each layer of the multi-layer isopleth.

[0130] In a possible implementation, there is an association relationship between the equally spaced points on adjacent isopleths in the multi-layer isopleth, and the association relationship is used to indicate the equally spaced points associated with each other on adjacent isopleths; wherein, the step of generating a carbon fiber printing path corresponding to each of the J carbon fiber winding layers according to the J offset angle values corresponding to each layer of the multi-layer isopleth includes: for the j-th carbon fiber winding layer among the J carbon fiber winding layers, offset the N equally spaced points on each layer of the isopleth according to the offset angle value corresponding to the j-th carbon fiber winding layer of each layer of the isopleth and the average layer height of the multi-layer isopleth to obtain N target equally spaced points after offset on each layer of the isopleth, 1 ≤ j ≤ J; according to the association relationship between the equally spaced points on adjacent isopleths in the multi-layer isopleth and the N target equally spaced points after offset on each layer of the isopleth, connect the corresponding target equally spaced points associated between adjacent isopleths in the multi-layer isopleth to obtain the carbon fiber printing path corresponding to the j-th carbon fiber winding layer.

[0131] In a possible implementation, the step of generating the multi-layer isopleth corresponding to the outer surface of the three-dimensional model includes: performing triangular meshing on the outer surface corresponding to the three-dimensional model to obtain a three-dimensional mesh model, where the three-dimensional mesh model represents the triangular meshed outer surface; determining a distance field corresponding to the three-dimensional model according to the positions of the grid points in the three-dimensional mesh model, where the distance field includes the distances from the grid points in the three-dimensional mesh model to a specified surface of the three-dimensional model, and the specified surface includes the edge surfaces at the head and tail ends of the three-dimensional model; generating the multi-layer isopleth corresponding to the outer surface of the three-dimensional model based on the distance field and a preset average layer height, where the seam positions between the multi-layer isopleths are aligned and the generation directions are the same; extracting N equally spaced points evenly distributed on each layer of the isopleth according to a preset average distance, and the N equally spaced points extracted on each layer of the isopleth are aligned with each other, and determining the equally spaced points aligned with each other on adjacent isopleths in the multi-layer isopleth as corresponding associated equally spaced points to obtain the association relationship between the equally spaced points on adjacent isopleths in the multi-layer isopleth, where the average distance represents the distance between two adjacent equally spaced points on the same isopleth.

[0132] In a possible implementation, determining the J offset angle values corresponding to each layer of contour lines based on the M angular values corresponding to each of the N equally spaced points on each layer of contour lines includes: for the N×M angular values on the x-th layer of contour lines, determining whether each of the N×M angular values is within a preset angular range, and in the case where there are angular values among the N×M angular values that do not belong to the preset angular range, correcting the angular values that do not belong to the preset angular range to the boundary value closest to the angular value within the preset angular range, to obtain the N×M target angular values corresponding to the N equally spaced points on the x-th layer of contour lines, where the preset angular range represents the angular range that enables the carbon fiber to be wound around the substrate; by statistically grouping the N×M target angular values, obtaining J angular groups divided within the preset angular range from the N×M target angular values and the central angular value corresponding to each of the J angular groups, where the central angular value corresponding to each angular group is the angular value with the smallest sum of distances from each target angular value within each angular group; determining the J offset angle values corresponding to the x-th layer of contour lines as the central angular values corresponding to the J angular groups respectively.

[0133] In a possible implementation, the preset angular range includes two opposite angular ranges, with r angular groups divided within each angular range, 2r = J, and the J offset angle values corresponding to the x-th layer of contour lines include the central angular values corresponding to the r angular groups divided within each of the two opposite angular ranges from the N×M target angular values.

[0134] In a possible implementation, for the j-th carbon fiber winding layer among the J carbon fiber winding layers, offsetting the N equally spaced points on each layer of contour lines according to the offset angle value corresponding to each layer of contour lines in the j-th carbon fiber winding layer and the average layer height of the multiple layers of contour lines to obtain the N target equally spaced points after offset on each layer of contour lines includes: for the x-th layer of contour lines in the j-th carbon fiber winding layer among the J carbon fiber winding layers, determining the offset amount of the x-th layer of contour lines under the j-th carbon fiber winding layer according to the offset angle value corresponding to the x-th layer of contour lines in the j-th carbon fiber winding layer and the average layer height; by accumulating the offset amount of the first layer of contour lines under the j-th carbon fiber winding layer to the offset amount of the x-th layer of contour lines under the j-th carbon fiber winding layer, obtaining the cumulative offset amount of the x-th layer of contour lines under the j-th carbon fiber winding layer; offsetting the N equally spaced points on the x-th layer of contour lines along the x-th layer of contour lines by the cumulative offset amount to obtain the N target equally spaced points after offset on the x-th layer of contour lines.

[0135] In a possible implementation, the offset of the x-th layer of contour lines under the j-th carbon fiber winding layer is expressed as: , and the cumulative offset of the x-th layer of contour lines under the j-th carbon fiber winding layer is expressed as ; where represents the average layer height, represents the offset angle value of the x-th layer of contour lines corresponding to the j-th carbon fiber winding layer.

[0136] In a possible implementation, based on the correlation relationship between the equidistant points on the adjacent contour lines in the multi-layer contour lines and the N target equidistant points after offset on each layer of contour lines, connecting the corresponding target equidistant points associated between the adjacent contour lines in the multi-layer contour lines to obtain the carbon fiber printing path corresponding to the j-th carbon fiber winding layer includes: based on the correlation relationship between the equidistant points on the adjacent contour lines in the multi-layer contour lines and the N target equidistant points after offset on each layer of contour lines, connecting the corresponding target equidistant points associated between the adjacent contour lines in the multi-layer contour lines, and softening the connection result to obtain the carbon fiber printing path corresponding to the j-th carbon fiber winding layer.

[0137] According to the three-dimensional printing path planning device of the embodiments of the present disclosure, obtaining the stress vector set through finite element analysis of the three-dimensional model of the substrate is equivalent to obtaining the stress distribution of the substrate under various loads. Furthermore, based on the stress distribution, determining the offset angle value of the equidistant points on the contour lines can make the offset angle values of the equidistant points on each layer of contour lines unified, and is beneficial to making the arrangement of the printing paths in each carbon fiber winding layer relatively uniform and covering the stress distribution in multiple directions of the substrate. Then, based on the J offset angle values corresponding to each layer of contour lines, the carbon fiber printing paths corresponding to the J layers of carbon fiber winding layers can be effectively determined, so that the carbon fiber reinforced layer obtained by three-dimensional printing according to the carbon fiber printing paths of the multi-layer carbon fiber winding layers can greatly improve the bearing capacity of the substrate, and can make the printing efficiency of three-dimensional printing higher and save more carbon fiber materials.

[0138] Based on the three-dimensional printing path planning device proposed in the above embodiments of the present disclosure, the embodiments of the present disclosure also propose a three-dimensional printing device. This device can be applied to the above three-dimensional printing system. The device includes:

[0139] A path determination module, configured to use the path planning device described above to determine the three-dimensional printing path planning result corresponding to the substrate. The three-dimensional printing path planning result includes the carbon fiber printing paths corresponding to each of the J carbon fiber winding layers;

[0140] An instruction determination module, configured to determine motion instructions of the main robotic arm and the auxiliary robotic arm during the printing process according to the three-dimensional printing path planning result;

[0141] A control module, configured to control the three-dimensional printing system to perform the printing work of the carbon fiber reinforced layer on the substrate based on the motion instructions of the main robotic arm and the auxiliary robotic arm during the printing process.

[0142] In a possible implementation manner, the substrate includes a substrate with the same cross-sectional shape and the same cross-sectional area between two ends; the substrate fixed to the substrate fixing frame is in a flat and inverted state, wherein determining the motion instructions of the main robotic arm and the auxiliary robotic arm during the printing process according to the three-dimensional printing path planning result includes: determining the substrate rotation data corresponding to each carbon fiber printing path in each carbon fiber winding layer according to the three-dimensional printing path planning result, where the substrate rotation data includes the rotation angle of the substrate during the printing process when the carbon fiber print head prints along each carbon fiber printing path; and determining the motion instructions of the main robotic arm and the auxiliary robotic arm during the printing process according to the substrate rotation data corresponding to each carbon fiber printing path in each carbon fiber winding layer.

[0143] The three-dimensional printing device according to the embodiments of the present disclosure can greatly improve the bearing capacity of the substrate when performing three-dimensional printing according to the carbon fiber printing paths of multiple layers of carbon fiber winding layers, and can make the printing efficiency of three-dimensional printing higher and save more carbon fiber materials.

[0144] In some embodiments, the functions or modules included in the device provided by the embodiments of the present disclosure can be used to execute the methods described in the method embodiments above. The specific implementation can refer to the description of the method embodiments above. For the sake of brevity, it will not be repeated here.

[0145] The embodiments of the present disclosure also propose a computer-readable storage medium, on which computer program instructions are stored, and when the computer program instructions are executed by a processor, the above methods are implemented. The computer-readable storage medium can be a volatile or non-volatile computer-readable storage medium.

[0146] The embodiments of the present disclosure also propose an electronic device, including: a processor; a memory for storing instructions executable by the processor; wherein, the processor is configured to implement the above methods when executing the instructions stored in the memory.

[0147] The embodiments of the present disclosure also provide a computer program product, including computer-readable code, or a non-volatile computer-readable storage medium carrying the computer-readable code, and when the computer-readable code runs in the processor of the electronic device, the processor in the electronic device executes the above methods.

[0148] Figure 15 FIG. 3 shows a block diagram of an electronic device 1900 according to an embodiment of the present disclosure. For example, the device 1900 may be provided as a server or a terminal device. Referring to Figure 15 , the device 1900 includes a processing component 1922, which further includes one or more processors, and memory resources represented by a memory 1932 for storing instructions executable by the processing component 1922, such as application programs. The application programs stored in the memory 1932 may include one or more modules each corresponding to a set of instructions. In addition, the processing component 1922 is configured to execute instructions to perform the above-described method.

[0149] The device 1900 may also include a power component 1926 configured to perform power management of the device 1900, a wired or wireless network interface 1950 configured to connect the device 1900 to a network, and an input / output interface 1958 (I / O interface). The device 1900 may operate based on an operating system stored in the memory 1932, such as Windows Server TM , MacOS X TM , Unix TM , Linux TM , FreeBSD TM or the like.

[0150] In an exemplary embodiment, a non-transitory computer-readable storage medium is also provided, such as the memory 1932 including computer program instructions, and the computer program instructions may be executed by the processing component 1922 of the device 1900 to complete the above-described method.

[0151] The present disclosure may be a system, a method, and / or a computer program product. The computer program product may include a computer-readable storage medium having thereon computer-readable program instructions for causing a processor to implement various aspects of the present disclosure.

[0152] A computer-readable storage medium can be a tangible device that can retain and store instructions for use by an instruction execution device. A computer-readable storage medium may be, for example—but not limited to—an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of the computer-readable storage medium include: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disc read-only memory (CD-ROM), a digital versatile disc (DVD), a memory stick, a floppy disk, a mechanically encoded device such as a punched card or raised structures in grooves having instructions stored thereon, and any suitable combination of the foregoing. The computer-readable storage medium as used herein is not construed as an instantaneous signal per se, such as a radio wave or other freely propagating electromagnetic wave, an electromagnetic wave propagated through a waveguide or other transmission medium (e.g., an optical pulse through an optical fiber cable), or an electrical signal transmitted through a wire.

[0153] The computer-readable program instructions described herein can be downloaded from a computer-readable storage medium to various computing / processing devices, or downloaded to an external computer or external storage device through a network, such as the Internet, a local area network, a wide area network, and / or a wireless network. The network may include a copper transmission cable, an optical fiber transmission, a wireless transmission, a router, a firewall, a switch, a gateway computer, and / or an edge server. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards the computer-readable program instructions for storage in a computer-readable storage medium in each computing / processing device.

[0154] The computer program instructions for performing the operations of the present disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine - related instructions, microcode, firmware instructions, state - setting data, or source code or object code written in any combination of one or more programming languages, including object - oriented programming languages such as Smalltalk, C++, etc., and conventional procedural programming languages such as the "C" language or similar programming languages. The computer - readable program instructions may be executed entirely on the user's computer, partially on the user's computer, executed as a stand - alone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., through the Internet using an Internet service provider). In some embodiments, by using the state information of the computer - readable program instructions to customize an electronic circuit, such as a programmable logic circuit, a field - programmable gate array (FPGA), or a programmable logic array (PLA), the electronic circuit can execute the computer - readable program instructions to implement various aspects of the present disclosure.

[0155] Aspects of the present disclosure are described herein with reference to the flowchart and / or block diagram of methods, apparatus (systems), and computer program products according to embodiments of the present disclosure. It should be understood that each block of the flowchart and / or block diagram, and combinations of blocks in the flowchart and / or block diagram, can be implemented by computer - readable program instructions.

[0156] These computer - readable program instructions can be provided to a processor of a general - purpose computer, a special - purpose computer, or other programmable data - processing apparatus to produce a machine such that the instructions, when executed by the processor of the computer or other programmable data - processing apparatus, create a means for implementing the functions / actions specified in one or more blocks of the flowchart and / or block diagram. These computer - readable program instructions can also be stored in a computer - readable storage medium, which causes a computer, a programmable data - processing apparatus, and / or other devices to operate in a particular manner, so that the computer - readable medium storing the instructions includes a manufacture comprising instructions for implementing various aspects of the functions / actions specified in one or more blocks of the flowchart and / or block diagram.

[0157] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device, causing a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process such that the instructions executed on the computer, other programmable data processing apparatus, or other device implement the functions / acts specified in one or more boxes of the flowchart and / or block diagram.

[0158] The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present disclosure. In this regard, each block in the flowchart or block diagram may represent a module, a segment of code, or a portion of an instruction, which contains one or more executable instructions for implementing the specified logical function. In some alternative implementations, the functions noted in the blocks may occur out of the order noted in the figures. For example, two consecutive blocks may in fact be executed substantially in parallel, or they may sometimes be executed in the reverse order, depending upon the functionality involved. It should also be noted that each block of the block diagrams and / or flowchart, and combinations of blocks in the block diagrams and / or flowchart, can be implemented by a dedicated hardware-based system that performs the specified functions or acts, or by a combination of dedicated hardware and computer instructions.

[0159] The embodiments of the present disclosure have been described above. The above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The choice of terms used herein is intended to best explain the principles of the embodiments, the practical application, or improvements made to the technology in the market, or to enable other ordinary skilled persons in the art to understand the embodiments disclosed herein.

Claims

1. A three-dimensional printing path planning method for a carbon fiber reinforced matrix, characterized in that, Including: By performing finite element analysis on the three-dimensional model of the matrix to be strengthened, a set of stress vectors corresponding to the matrix is obtained, and the set of stress vectors characterizes the distribution of the stress vectors received by the matrix under each of the M kinds of loads; Generating multi-layer contour lines corresponding to the outer surface of the three-dimensional model, and each layer of contour lines includes N equally spaced points evenly distributed thereon; According to the set of stress vectors, determine the M stress vectors received by each equally spaced point on each layer of contour lines. The M stress vectors received by each equally spaced point include the stress vectors received by each equally spaced point under each of the M kinds of loads; By calculating the angles between the M stress vectors received by each equally spaced point on each layer of contour lines and the tangent vectors of each equally spaced point on the contour line to which it belongs, M angle values corresponding to each equally spaced point on each layer of contour lines are obtained; According to the M angle values corresponding to each equally spaced point among the N equally spaced points on each layer of contour lines, determine J offset angle values corresponding to each layer of contour lines; According to the J offset angle values corresponding to each layer of contour lines in the multi-layer contour lines, generate carbon fiber printing paths corresponding to each carbon fiber winding layer in the J carbon fiber winding layers.

2. The method according to claim 1, characterized in that, There is an association relationship between the equally spaced points on adjacent contour lines in the multi-layer contour lines, and the association relationship is used to indicate the equally spaced points that are associated with each other on adjacent contour lines; wherein, the step of generating carbon fiber printing paths corresponding to each carbon fiber winding layer in the J carbon fiber winding layers according to the J offset angle values corresponding to each layer of contour lines in the multi-layer contour lines includes: For the j-th carbon fiber winding layer among the J carbon fiber winding layers, offset the N equally spaced points on each layer of contour lines according to the offset angle value corresponding to the j-th carbon fiber winding layer of each layer of contour lines and the average layer height of the multi-layer contour lines, to obtain N target equally spaced points after offset on each layer of contour lines, where 1≤j≤J; According to the association relationship between the equally spaced points on adjacent contour lines in the multi-layer contour lines and the N target equally spaced points after offset on each layer of contour lines, connect the corresponding target equally spaced points associated between adjacent contour lines in the multi-layer contour lines to obtain the carbon fiber printing path corresponding to the j-th carbon fiber winding layer.

3. The method according to claim 1, wherein The step of generating multi-layer contour lines corresponding to the outer surface of the three-dimensional model includes: Performing triangular meshing on the outer surface corresponding to the three-dimensional model to obtain a three-dimensional mesh model, and the three-dimensional mesh model characterizes the triangulated outer surface; According to the positions of the grid points in the three-dimensional mesh model, determine the distance field corresponding to the three-dimensional model, and the distance field includes the distances from the grid points in the three-dimensional mesh model to the specified surface of the three-dimensional model, and the specified surface includes the edge surfaces at both ends of the three-dimensional model; Based on the distance field and the preset average layer height, generate multi-layer contour lines corresponding to the outer surface of the three-dimensional model, wherein the seam positions between the multi-layer contour lines are aligned and the generation directions are the same; According to a preset average distance, N equidistant points evenly distributed are extracted on each layer of the isoline, and the N equidistant points respectively extracted on each layer of the isoline are aligned with each other. The equidistant points on adjacent isolines in the multi-layer isoline are determined as corresponding associated equidistant points, and the association relationship between the equidistant points on adjacent isolines in the multi-layer isoline is obtained. The average distance represents the distance between two adjacent equidistant points on the same isoline.

4. The method according to claim 1, characterized in that, Determining J offset angle values corresponding to each layer of the isoline according to M angle values corresponding to each of the N equidistant points on each layer of the isoline includes: For the N×M angle values on the x-th layer of the isoline, determine whether each of the N×M angle values is within a preset angle range. In the case where there are angle values among the N×M angle values that do not belong to the preset angle range, correct the angle values that do not belong to the preset angle range to the boundary value closest to the angle value in the preset angle range, and obtain N×M target angle values corresponding to the N equidistant points on the x-th layer of the isoline. The preset angle range represents the angle range that enables the carbon fiber to be wound around the matrix. By performing statistical grouping on the N×M target angle values, J angle groups divided by the N×M target angle values within the preset angle range and the central angle value corresponding to each of the J angle groups are obtained. Determine the central angle values corresponding to the J angle groups as the J offset angle values corresponding to the x-th layer of the isoline.

5. The method according to claim 4, characterized in that, The preset angle range includes two opposite angle ranges, and r angle groups are divided within each angle range, 2r = J. The J offset angle values corresponding to the x-th layer of the isoline include the central angle values corresponding to the r angle groups divided within each of the two opposite angle ranges by the N×M target angle values.

6. The method according to claim 2, wherein For the j-th carbon fiber winding layer among the J carbon fiber winding layers, offsetting the N equidistant points on each layer of the isoline according to the offset angle value corresponding to the j-th carbon fiber winding layer of each layer of the isoline and the average layer height of the multi-layer isoline to obtain N target equidistant points after offset on each layer of the isoline includes: For the x-th layer of the isoline of the j-th carbon fiber winding layer among the J carbon fiber winding layers, determine the offset amount of the x-th layer of the isoline under the j-th carbon fiber winding layer according to the offset angle value corresponding to the x-th layer of the isoline under the j-th carbon fiber winding layer and the average layer height. By accumulating the offset amount of the first layer of the isoline under the j-th carbon fiber winding layer to the offset amount of the x-th layer of the isoline under the j-th carbon fiber winding layer, obtain the cumulative offset amount of the x-th layer of the isoline under the j-th carbon fiber winding layer. According to the cumulative offset amount of the x-th layer of the isoline under the j-th carbon fiber winding layer, offset the N equidistant points on the x-th layer of the isoline along the x-th layer of the isoline by the cumulative offset amount to obtain N target equidistant points after offset on the x-th layer of the isoline.

7. The method according to claim 6, characterized in that, The offset of the x-th layer contour line under the j-th carbon fiber winding layer is expressed as: , and the cumulative offset of the x-th layer contour line under the j-th carbon fiber winding layer is expressed as ; Among them, represents the average floor height, represents the offset angle value corresponding to the x-th contour line in the j-th carbon fiber winding layer.

8. A three-dimensional printing method for a carbon fiber reinforced matrix, characterized in that, The printing method is applied to a three-dimensional printing system, which includes a main robotic arm, an auxiliary robotic arm, a carbon fiber print head, and a matrix fixing frame. The carbon fiber print head is installed on the auxiliary robotic arm, and the matrix fixing frame is installed on the main robotic arm. The carbon fiber print head is used to generate carbon fiber filaments, and the matrix fixing frame is used to fix the matrix to be strengthened. The printing method includes: Using the path planning method according to any one of claims 1 to 7, determining the three-dimensional printing path planning result corresponding to the matrix, where the three-dimensional printing path planning result includes the carbon fiber printing paths corresponding to each carbon fiber winding layer in J carbon fiber winding layers; According to the three-dimensional printing path planning result, determining the motion instructions of the main robotic arm and the auxiliary robotic arm during the printing process respectively; Based on the motion instructions of the main robotic arm and the auxiliary robotic arm during the printing process respectively, controlling the three-dimensional printing system to perform the printing work of the carbon fiber reinforcement layer on the matrix.

9. The method according to claim 8, wherein The matrix includes a matrix with the same cross-sectional shape and the same cross-sectional area between both ends; the matrix fixed to the matrix fixing frame is in a flat and inverted state. Among them, according to the three-dimensional printing path planning result, determining the motion instructions of the main robotic arm and the auxiliary robotic arm during the printing process respectively includes: According to the three-dimensional printing path planning result, determining the matrix rotation data corresponding to each carbon fiber printing path in each carbon fiber winding layer, where the matrix rotation data includes the rotation angle of the matrix during the printing process by the carbon fiber print head along each carbon fiber printing path; According to the matrix rotation data corresponding to each carbon fiber printing path in each carbon fiber winding layer, determining the motion instructions of the main robotic arm and the auxiliary robotic arm during the printing process respectively.

10. An electronic device, characterized in that, It includes: A processor; A memory for storing instructions executable by the processor; Among them, the processor is configured to implement the method according to any one of claims 1 to 9 when executing the instructions stored in the memory.

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