A porous cellular conformal adaptive filling method for additive manufacturing of curved special-shaped parts

Abstract

The present application relates to a kind of porous cell conformal adaptive filling method for the curved surface special-shaped part of additive manufacturing, belong to the field of additive manufacturing.A kind of porous cell conformal adaptive filling method for the curved surface special-shaped part of additive manufacturing, comprising: constructing filling cell body, determining the normal filling vector m n1 And tangential filling vector m t1 Of filling cell body;Extract the filling surface of special-shaped curved surface structure, obtain plane contour line;In plane contour line, grid line is divided, and grid line intersection is mapped to filling surface to obtain filling node;Extract the normal vector m n2 And tangential vector m t2 Of filling node on filling surface;Adaptive filling of filling cell body is carried out;Filling cell body is merged to obtain special-shaped curved surface structure cell adaptive filling model, and after model post-processing, additive manufacturing is carried out.The method can be according to the shape and curvature of special-shaped curved surface structure, angle adjustment and layout optimization are carried out to cell, and the angle adaptive cell filling of different special-shaped complex curved surface structure is realized.

Description

Technical Field

[0001] This invention relates to the field of additive manufacturing, and in particular to a method for conformal adaptive filling of porous unit cells for additive manufacturing of irregularly shaped curved parts. Background Technology

[0002] Irregular curved surface structures are characterized by their complexity, large curvature variations, and extreme combinations of sizes. Even minute defects or errors can significantly impact the structure's integrity and performance, requiring precise manufacturing techniques to ensure their shape and quality. These characteristics present significant challenges in the design and manufacture of irregular curved surface structures, necessitating precise control of each manufacturing step and rigorous quality control to ensure the final product's performance and quality. Irregular curved surface structures have wide applications in aerospace, medical devices, and other fields. For example, in the medical field, guided bone regeneration membranes for the oral cavity are used. Cell filling methods in irregular curved surface structures can effectively improve properties such as specific strength, stiffness, and stability. Furthermore, by adjusting the shape, size, and material of the cell, optimizations in lightweighting, impact resistance, and thermal stability can be achieved.

[0003] Grasshopper is a plugin that runs in the Rhino environment and uses procedural algorithms to generate models. It is widely used in fields such as architectural design, engineering, art, and manufacturing. Grasshopper can build a complete model generation logic through a series of modular operators. The algorithm network and component parameters can be modified as needed, and the computer executes these operators to generate the final model and achieve the desired design effect.

[0004] Additive manufacturing technology, with its ability to manufacture arbitrarily complex structures, will play an extremely important role in the design and manufacture of many complex curved and irregular structures. However, the current construction methods for adaptive filling of unit cells for curved and irregular parts are generally quite difficult, and it is hard to adjust the angle and optimize the layout of the unit cells according to the shape and curvature of the curved surface structure of the part. Summary of the Invention

[0005] Therefore, it is necessary to provide a porous unit cell conformal adaptive filling method for additive manufacturing curved irregular parts, which solves the problem that the current construction methods for adaptive filling of unit cells for curved irregular parts are difficult and it is hard to adjust the angle and optimize the layout of the unit cell according to the shape and curvature of the part's curved surface structure.

[0006] A method for conformal adaptive filling of porous unit cells for additive manufacturing of irregularly shaped curved parts includes the following steps:

[0007] S1. Construct the filled unit cell, set the filling spacing of the filled unit cell, and determine the normal filling vector m of the filled unit cell. n1and tangential filling vector m t1 ;

[0008] S2. Extract the filled surface of the irregular curved surface structure, set the baseline and reference line, and unfold the filled surface into a plane to obtain the plane contour line;

[0009] S3. Divide grid lines within the planar contour line according to the filling spacing of the filling unit cells, and map the intersection of the grid lines to the filling surface to obtain the filling nodes.

[0010] S4. Extract the normal vector m of the fill node on the fill surface. n2 and tangential vector m t2 ;

[0011] S5. Perform adaptive filling of the filling unit cell, and set the normal filling vector m of the filling unit cell. n1 With the normal vector m of the filling node n2 Overlapping, tangential filling vector m of the filling unit cell t1 Tangential vector m of the filling node t2 coincide;

[0012] S6. Merge the filled unit cells to obtain the irregular curved surface structure unit cell adaptive filling model, import the irregular curved surface structure unit cell adaptive filling model for post-processing, and set the processing parameters for additive manufacturing.

[0013] This application discloses a conformal adaptive filling method for porous unit cells of irregularly shaped curved parts for additive manufacturing. During the filling process, by aligning the normal and tangential filling vectors of the filled unit cell with the corresponding vectors of the filling nodes, adaptive filling of the filled unit cell is achieved. This method can adapt to the deformation and stress distribution of irregularly shaped curved structures, improving the overall performance of the structure. After post-processing and setting processing parameters, the adaptive filling model of the irregularly shaped curved structure unit cell can be directly used for additive manufacturing, simplifying the processing and improving production efficiency and manufacturing quality. This type of unit cell filling method can construct unit cells with different requirements based on parameters such as the unit cell shape and size, and the position and distance of the filling nodes, realizing angle-adaptive unit cell filling of irregularly shaped curved structures such as GBR films, and achieving diversified design of porous irregularly shaped curved structures. Furthermore, the controllability of various parameters of this type of lattice model has been improved, and the boundary damage problem of conventional cell filling can be avoided, ensuring the integrity of the lattice. This results in a more uniform stress distribution under load, further enhancing the mechanical strength of porous irregular structures and enabling additively manufactured curved irregular parts to have better load-bearing capacity and durability.

[0014] In any of the above technical solutions, in step S1, the filling unit cell includes various crystal unit cell lattices such as body-centered cubic (BCC), octahedral cubic (ROC), face-centered cubic (FCC), regular hexahedron (Cubic), cubic octahedron (Cuboctahedron), truncated octahedron (Truncated octahedron), regular dodecahedron (Dodecahedron), rhombic dodecahedron (Rhombic dodecahedron), regular icosahedron (Icosahedron), diamond (Diamond), truncated hexagonal tessellation (kagome), small rhombic truncated cube (Rhombic cuboctahedron), honeycomb (Honeycomb), and foam (Foam).

[0015] By filling unit cells with a variety of crystal unit cell lattices, this method provides a wide range of choices for the fabrication of different materials, meeting the needs of various application scenarios. This allows the porous unit cell conformal adaptive filling method for additive manufacturing curved and irregularly shaped parts to adapt to the characteristics and requirements of different materials, improving the flexibility and adaptability of material preparation. Different crystal unit cell lattices possess different physical and chemical properties, such as hardness, thermal conductivity, and optical properties. Selecting a suitable crystal unit cell lattice can optimize material performance and meet the needs of specific applications.

[0016] In any of the above technical solutions, in step S1, the filling spacing includes a lateral spacing d1 and a longitudinal spacing d2, and the filling spacing is designed according to the size of the filled unit cell to ensure the connectivity between units; the normal filling vector m n1 The normal filling vector m is the direction vector of the shortest side of the rectangle that fills the boundary of the unit cell. n2 Let be the direction vector of the longest side of the bounding rectangle of the filled unit cell.

[0017] By precisely setting the infill spacing, space can be utilized more effectively, waste reduced, and material utilization improved. Designing the infill spacing based on the dimensions of the infill unit cells ensures connectivity between them, thereby enhancing the overall structural stability and reducing the risk of structural failure due to poor connections. Using the normal infill vector to determine the infill direction increases the adaptability and flexibility of the infill scheme. Precise control of the infill spacing and direction reduces errors during the infill process and improves infill quality.

[0018] In any of the above technical solutions, in step S2, the baseline is set on the filled surface, the reference line is set on the unfolded filled surface, the filled surface is flattened and a planar contour line is output, and the envelope area of ​​the unfolded planar contour line is set to be consistent with the area of ​​the filled surface.

[0019] By setting the baseline on the infill surface and the reference line on the unfolded infill surface, the geometric features of the infill surface can be accurately preserved during unfolding, thereby improving the accuracy of the unfolded planar contour. Ensuring that the envelope area of ​​the unfolded planar contour matches the area of ​​the infill surface reduces errors caused by surface deformation and stretching during unfolding, improving the matching degree between the unfolded planar contour and the actual infill surface. Furthermore, flattening the infill surface and outputting the planar contour makes this porous unit cell conformal adaptive infilling method for additive manufacturing of irregularly shaped curved parts applicable to infill surfaces of various shapes, exhibiting strong adaptability and meeting the needs of different application scenarios.

[0020] In any of the above technical solutions, step S3, which involves dividing the grid lines and obtaining the filled nodes, includes the following specific steps:

[0021] S31. Extract the control points and center point of the planar contour line. Measure the distance between the center point and each control point on the planar contour line. Take the maximum distance dm. Draw a rectangular border with a side length of dm+x to ensure that the rectangular border completely encloses the planar contour. Here, x is a positive number and the unit of x is consistent with the unit of dm.

[0022] S32. Take points at equal intervals d1 in the horizontal direction of the rectangular border and at equal intervals d2 in the vertical direction of the rectangular border. Connect the corresponding points to form grid lines, and calculate and obtain the grid intersections.

[0023] S33. Determine whether each grid intersection point is within the plane contour line and output the corresponding Boolean value, and retain the grid intersection points within the plane contour line;

[0024] S34. Map the mesh intersections within the planar contour to the filled surface to obtain the filled nodes.

[0025] By extracting the control points and center point of the planar contour, measuring the distance between the center point and each control point, and taking the maximum distance dm, a rectangular border is drawn with a side length of dm+x, where x can be a positive number such as 0.1, 0.5, 1, 2, 3, 4, etc., ensuring that the length of dm+x is greater than the length of dm. This ensures that the drawn rectangular border completely encloses the planar contour and accurately determines the boundary of the filling area, thus ensuring that the filling operation is performed within a predetermined range. Points are taken at equal intervals in the horizontal and vertical directions of the rectangular border and connected to form grid lines, which can quickly construct the grid structure of the filling area and obtain grid intersections, helping to improve the efficiency of the filling operation. Judging and truncating the grid intersections within the planar contour ensures that fill nodes are generated only in the areas that need to be filled, thus avoiding unnecessary filling and improving the filling quality. Mapping the grid intersections within the planar contour to the filling surface obtains accurate fill nodes, improving subsequent filling accuracy and efficiency. Furthermore, this filling method is applicable to irregular planar contours, exhibiting strong adaptability and versatility. The spacing of the grid lines can also be adjusted as needed to adapt to different design requirements and fill density.

[0026] In any of the above technical solutions, in step S4, the normal vector m of the filling node on the filling surface is extracted. n2 and tangential vector m t2 The specific steps are as follows:

[0027] S41. Extract the normal vector m of the fill node on the fill surface. n2 ;

[0028] S42. Group the fill nodes and connect the fill nodes in the same group to obtain the fill curve;

[0029] S43. Extract the tangential vector m of the fill node along the fill curve direction. t2 .

[0030] By extracting the normal and tangential vectors of the fill nodes on the fill surface, the shape and orientation of the fill surface can be determined more accurately, thereby improving fill accuracy and ensuring fill quality. Grouping fill nodes and connecting nodes within the same group to obtain the fill curve ensures the continuity of the fill curve on the surface, avoiding surface breaks or discontinuities caused by improper node grouping. This fill method is applicable to various types of fill surfaces, exhibiting strong adaptability and versatility. Furthermore, accurate vector extraction and node grouping can reduce potential errors during the design process, improving design reliability.

[0031] In any of the above technical solutions, in step S5, adaptive filling of the filling unit cells is performed, and the specific steps are as follows:

[0032] S51. Using the center of the filled cell and the filled nodes as reference points, move the filled cell and copy it to all filled nodes;

[0033] S52. Rotate the filled unit cells so that the normal filling vector m of each filled unit cell is... n1 The normal vector m of the corresponding fill node on the fill surface n2 Overlap, that is:

[0034] m n1i =m n2i (i = 1, 2, ..., n) where n is the number of nodes to be filled;

[0035] S53. Rotate the filling unit cells again, so that the tangential filling vector m of each filling unit cell is... t1 The tangent vector m of the corresponding fill node on the fill curve t2 Overlap, that is:

[0036] m t1i =m t2i (i = 1, 2, ..., n).

[0037] The adaptive infill method dynamically adjusts the position and orientation of the infill unit cell based on the specific shape and location of the infill surface, thereby improving infill efficiency. Ensuring that the normal and tangential infill vectors of the infill unit cell coincide with the normal and tangential vectors of the corresponding infill nodes guarantees the accuracy and consistency of the infill results. Precise infill ensures the structural integrity and performance of the product, especially in applications requiring high loads or specific functional requirements.

[0038] In any of the above technical solutions, step S6 involves setting processing parameters for additive manufacturing, and the specific steps are as follows:

[0039] The placement is based on the principle of minimum Z-axis height, and the support type is conical.

[0040] Set the processing laser power, spot diameter, slice thickness, and tapered support parameters;

[0041] Complete additive manufacturing.

[0042] By importing an adaptive infill model of a non-circular curved surface structure, a support structure that meets design requirements can be quickly generated, improving manufacturing efficiency. The use of a tapered support type enhances the stability of the support structure and reduces the risk of deformation and breakage during additive manufacturing. Parameters such as processing laser power, spot diameter, and slice thickness are set to precisely control the processing quality during additive manufacturing, ensuring product accuracy and surface quality. By setting the tapered support parameters, the shape and size of the support structure can be flexibly adjusted according to different manufacturing needs and material properties, enabling the creation of complex and high-performance non-circular curved surface structures to meet the needs of various industries and application scenarios.

[0043] In any of the above technical solutions, in step S6, the additive manufacturing includes one of binder spraying, material extrusion, material spraying, powder bed melting, and stereolithography.

[0044] In any of the above technical solutions, in step S6, the additive manufacturing material includes one of metals, polymers, ceramics, or a composite material thereof. Attached Figure Description

[0045] Figure 1 A schematic diagram of a porous unit cell conformal adaptive filling method for additive manufacturing of curved irregular parts;

[0046] Figure 2 A flowchart illustrating the process of dividing grid lines and obtaining filled nodes;

[0047] Figure 3 A flowchart illustrating the process of extracting the normal and tangential vectors of the filled nodes on the filled surface;

[0048] Figure 4 A schematic diagram of the process for adaptive filling of filling units;

[0049] Figure 5 A schematic diagram of the filled unit cell established in this invention;

[0050] Figure 6 A schematic diagram of the irregular curved surface structure established for this invention;

[0051] Figure 7 A schematic diagram of the planar contour line obtained by unfolding the irregular curved surface structure established for this invention;

[0052] Figure 8 A schematic diagram of obtaining filled nodes by the filled surface mapping established in this invention;

[0053] Figure 9 A schematic diagram of the normal and tangential vectors of the filling node on the filling surface established for this invention;

[0054] Figure 10This is a schematic diagram of the angle-adaptive unit cell filling established in this invention. Detailed Implementation

[0055] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0056] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0057] The following describes, with reference to the accompanying drawings, a method for adaptive filling of porous unit cells for additive manufacturing of curved and irregularly shaped parts, according to some embodiments of the present invention.

[0058] Example 1

[0059] like Figure 1 As shown, a method for conformal adaptive filling of porous unit cells for additive manufacturing of curved irregular parts includes the following steps:

[0060] S1. Construct the filled unit cell, set the filling spacing of the filled unit cell, and determine the normal filling vector m of the filled unit cell. n1 and tangential filling vector m t1 ;

[0061] S2. Extract the filled surface of the irregular curved surface structure, set the baseline and reference line, and unfold the filled surface into a plane to obtain the plane contour line;

[0062] S3. Divide grid lines within the planar contour line according to the filling spacing of the filling unit cells, and map the intersection of the grid lines to the filling surface to obtain the filling nodes.

[0063] S4. Extract the normal vector m of the fill node on the fill surface. n2 and tangential vector m t2 ;

[0064] S5. Perform adaptive filling of the filling unit cell, and set the normal filling vector m of the filling unit cell. n1 With the normal vector m of the filling node n2 Overlapping, tangential filling vector m of the filling unit cell t1 Tangential vector m of the filling node t2 coincide;

[0065] S6. Merge the filled unit cells to obtain the irregular curved surface structure unit cell adaptive filling model, import the irregular curved surface structure unit cell adaptive filling model for post-processing, and set the processing parameters for additive manufacturing.

[0066] This application discloses a conformal adaptive filling method for porous unit cells of irregularly shaped curved parts for additive manufacturing. During the filling process, by aligning the normal and tangential filling vectors of the filled unit cell with the corresponding vectors of the filling nodes, adaptive filling of the filled unit cell is achieved. This method can adapt to the deformation and stress distribution of irregularly shaped curved structures, improving the overall performance of the structure. After post-processing, the adaptive filling model of the irregularly shaped curved structure unit cell can be directly used for additive manufacturing by setting processing parameters, simplifying the processing and improving production efficiency and manufacturing quality. This type of unit cell filling method can construct unit cells with different requirements by setting parameters such as unit cell shape and size, filling node position and distance, etc., to achieve angle-adaptive unit cell filling of irregularly shaped curved structures such as GBR films, enabling diversified design of porous irregularly shaped curved structures. Furthermore, the controllability of various parameters of this type of lattice model has been improved, and the boundary damage problem of conventional cell filling can be avoided, ensuring the integrity of the lattice. This results in a more uniform stress distribution under load, further enhancing the mechanical strength of porous irregular structures and enabling additively manufactured curved irregular parts to have better load-bearing capacity and durability.

[0067] In any of the above technical solutions, in step S1, the filling unit cell includes various crystal unit cell lattices such as body-centered cubic (BCC), octahedral cubic (ROC), face-centered cubic (FCC), regular hexahedron (Cubic), cubic octahedron (Cuboctahedron), truncated octahedron (Truncated octahedron), regular dodecahedron (Dodecahedron), rhombic dodecahedron (Rhombic dodecahedron), regular icosahedron (Icosahedron), diamond (Diamond), truncated hexagonal tessellation (kagome), small rhombic truncated cube (Rhombic cuboctahedron), honeycomb (Honeycomb), and foam (Foam).

[0068] By filling unit cells with a variety of crystal unit cell lattices, this method provides a wide range of choices for the fabrication of different materials, meeting the needs of various application scenarios. This allows the porous unit cell conformal adaptive filling method for additive manufacturing curved and irregularly shaped parts to adapt to the characteristics and requirements of different materials, improving the flexibility and adaptability of material preparation. Different crystal unit cell lattices possess different physical and chemical properties, such as hardness, thermal conductivity, and optical properties. Selecting a suitable crystal unit cell lattice can optimize material performance and meet the needs of specific applications.

[0069] In any of the above technical solutions, in step S1, the filling spacing includes a lateral spacing d1 and a longitudinal spacing d2. The filling spacing is designed according to the size of the filled unit cell to ensure the connectivity between units; the normal filling vector m n1 Let m be the direction vector of the shortest side of the rectangle filling the unit cell boundary, and m be the normal filling vector. n2 This is the direction vector of the longest side of the rectangle that fills the unit cell boundary.

[0070] By precisely setting the infill spacing, space can be utilized more effectively, waste reduced, and material utilization improved. Designing the infill spacing based on the dimensions of the infill unit cells ensures connectivity between them, thereby enhancing the overall structural stability and reducing the risk of structural failure due to poor connections. Using the normal infill vector to determine the infill direction increases the adaptability and flexibility of the infill scheme. Precise control of the infill spacing and direction reduces errors during the infill process and improves infill quality.

[0071] In any of the above technical solutions, in step S2, the baseline is set on the filled surface, the reference line is set on the unfolded filled surface, the filled surface is flattened and the planar contour line is output, and the envelope area of ​​the unfolded planar contour line is set to be consistent with the area of ​​the filled surface.

[0072] By setting the baseline on the infill surface and the reference line on the unfolded infill surface, the geometric features of the infill surface can be accurately preserved during unfolding, thereby improving the accuracy of the unfolded planar contour. Ensuring that the envelope area of ​​the unfolded planar contour matches the area of ​​the infill surface reduces errors caused by surface deformation and stretching during unfolding, improving the matching degree between the unfolded planar contour and the actual infill surface. Furthermore, flattening the infill surface and outputting the planar contour makes this porous unit cell conformal adaptive infilling method for additive manufacturing of irregularly shaped curved parts applicable to infill surfaces of various shapes, exhibiting strong adaptability and meeting the needs of different application scenarios.

[0073] like Figure 2 As shown, in any of the above technical solutions, in step S3, the grid lines are divided and the fill nodes are obtained. The specific steps are as follows:

[0074] S31. Extract the control points and center point of the planar contour line. Measure the distance between the center point and each control point on the planar contour line. Take the maximum distance dm. Draw a rectangular border with a side length of dm+x to ensure that the rectangular border completely encloses the planar contour. Here, x is a positive number and the unit of x is consistent with the unit of dm.

[0075] S32. Take points at equal intervals d1 in the horizontal direction of the rectangular border and at equal intervals d2 in the vertical direction of the rectangular border. Connect the corresponding points to form grid lines, and calculate and obtain the grid intersections.

[0076] S33. Determine whether each grid intersection point is within the plane contour line and output the corresponding Boolean value, and retain the grid intersection points within the plane contour line;

[0077] S34. Map the mesh intersections within the planar contour to the filled surface to obtain the filled nodes.

[0078] By extracting the control points and center point of the planar contour, measuring the distance between the center point and each control point, and taking the maximum distance dm, a rectangular border is drawn with a side length of dm+x, where x can be a positive number such as 0.1, 0.5, 1, 2, 3, 4, etc., ensuring that the length of dm+x is greater than the length of dm. This ensures that the drawn rectangular border completely encloses the planar contour and accurately determines the boundary of the filling area, thus ensuring that the filling operation is performed within a predetermined range. Points are taken at equal intervals in the horizontal and vertical directions of the rectangular border and connected to form grid lines, which can quickly construct the grid structure of the filling area and obtain grid intersections, helping to improve the efficiency of the filling operation. Judging and truncating the grid intersections within the planar contour ensures that fill nodes are generated only in the areas that need to be filled, thus avoiding unnecessary filling and improving the filling quality. Mapping the grid intersections within the planar contour to the filling surface obtains accurate fill nodes, improving subsequent filling accuracy and efficiency. Furthermore, this filling method is applicable to irregular planar contours, exhibiting strong adaptability and versatility. The spacing of the grid lines can also be adjusted as needed to adapt to different design requirements and fill density.

[0079] like Figure 3 As shown, in any of the above technical solutions, in step S4, the normal vector m of the filling node on the filling surface is extracted. n2 and tangential vector m t2 The specific steps are as follows:

[0080] S41. Extract the normal vector m of the fill node on the fill surface. n2 ;

[0081] S42. Group the fill nodes and connect the fill nodes in the same group to obtain the fill curve;

[0082] S43. Extract the tangential vector m of the fill node along the fill curve direction. t2 .

[0083] By extracting the normal and tangential vectors of the fill nodes on the fill surface, the shape and orientation of the fill surface can be determined more accurately, thereby improving fill accuracy and ensuring fill quality. Grouping fill nodes and connecting nodes within the same group to obtain the fill curve ensures the continuity of the fill curve on the surface, avoiding surface breaks or discontinuities caused by improper node grouping. This fill method is applicable to various types of fill surfaces, exhibiting strong adaptability and versatility. Furthermore, accurate vector extraction and node grouping can reduce potential errors during the design process, improving design reliability.

[0084] like Figure 4 As shown, in any of the above technical solutions, in step S5, adaptive filling of the filling unit cells is performed, and the specific steps are as follows:

[0085] S51. Using the center of the filled cell and the filled nodes as reference points, move the filled cell and copy it to all filled nodes;

[0086] S52. Rotate the filled unit cells so that the normal filling vector m of each filled unit cell is... n1 The normal vector m of the corresponding fill node on the fill surface n2 Overlap, that is:

[0087] m n1i =m n2i (i = 1, 2, ..., n) where n is the number of nodes to be filled;

[0088] S53. Rotate the filling unit cells again, so that the tangential filling vector m of each filling unit cell is... t1 The tangent vector m of the corresponding fill node on the fill curve t2 Overlap, that is:

[0089] m t1i =m t2i (i = 1, 2, ..., n).

[0090] The adaptive infill method dynamically adjusts the position and orientation of the infill unit cell based on the specific shape and location of the infill surface, thereby improving infill efficiency. Ensuring that the normal and tangential infill vectors of the infill unit cell coincide with the normal and tangential vectors of the corresponding infill nodes guarantees the accuracy and consistency of the infill results. Precise infill ensures the structural integrity and performance of the product, especially in applications requiring high loads or specific functional requirements.

[0091] In any of the above technical solutions, step S6 involves setting processing parameters for additive manufacturing, and the specific steps are as follows:

[0092] The placement is based on the principle of minimum Z-axis height, and the support type is conical.

[0093] Set the processing laser power, spot diameter, slice thickness, and tapered support parameters;

[0094] Complete additive manufacturing.

[0095] By importing an adaptive infill model of a non-circular curved surface structure, a support structure that meets design requirements can be quickly generated, improving manufacturing efficiency. The use of a tapered support type enhances the stability of the support structure and reduces the risk of deformation and breakage during additive manufacturing. Parameters such as processing laser power, spot diameter, and slice thickness are set to precisely control the processing quality during additive manufacturing, ensuring product accuracy and surface quality. By setting the tapered support parameters, the shape and size of the support structure can be flexibly adjusted according to different manufacturing needs and material properties, enabling the creation of complex and high-performance non-circular curved surface structures to meet the needs of various industries and application scenarios.

[0096] In any of the above technical solutions, in step S6, additive manufacturing includes one of binder spraying, material extrusion, material spraying, powder bed melting, and stereolithography.

[0097] In any of the above technical solutions, in step S6, the additive manufacturing material includes one of metals, polymers, ceramics, or a composite material thereof.

[0098] Example 2

[0099] like Figure 1 As shown, the present invention provides a method for conformal adaptive filling of porous unit cells for additive manufacturing of curved irregular parts, comprising the following steps:

[0100] (1) Selecting a regular octahedral cubic prism as the filling unit cell, and combining it with manufacturing process parameters, complete the parametric model construction of the filling unit cell, the structure of which is as follows: Figure 5 As shown. Its boundary dimensions are 0.52mm × 0.52mm × 0.68mm, and the diameter of the support column is 0.12mm.

[0101] Among them, the shortest path filling vector n of the regular octahedron is determined. t and the shortest path filling vector n t The shortest path fills the vector n t Let n be the vector representing the direction of the shortest path from one point in the unit cell to another, while the longest path fill vector is n. l This is the vector along the longest path from one point in the unit cell to another. In practical construction, an appropriate filling vector can be selected as needed. For example, by selecting the unit cell filling vector, the irregular curved surface filling structure can have a higher density or better structural performance in a certain direction.

[0102] (2) The selected irregular curved surface structure is Figure 6 The guided bone regeneration (GBR) membrane structure shown is as follows: Figure 7 As shown, the filled surface of the irregular curved surface structure is extracted, a baseline and a reference line are set, and the filled surface is unfolded in a plane to obtain a planar contour line;

[0103] The baseline is set on the filled surface, the reference line is set on the unfolded filled surface, the filled surface dataset is extracted, flattened and output as a planar contour line, and the envelope area of ​​the unfolded planar contour line is set to be consistent with the area of ​​the filled surface.

[0104] (3) Figure 8 As shown, grid lines are divided within the planar contour line according to the filling spacing of the filled unit cells. The intersections of the grid lines are then mapped to the filled surface to obtain the filled nodes. The specific steps are as follows:

[0105] (a) Extract the control points of the plane contour line, and at the same time extract the center point of the plane contour. Measure the distance between the center point and each control point on the plane contour line, take the maximum distance dm, and draw a rectangular border with 2*(dm+1) as the side length so that the rectangular border encloses the plane contour.

[0106] (b) Take points at equal intervals of d1 = 0.56 and d2 = 0.44 in the horizontal and vertical directions of the rectangular border, respectively, connect the corresponding points to form grid lines, and obtain the grid intersections;

[0107] (c) Determine whether each grid intersection point is within the plane contour line and output the corresponding Boolean value, and retain the grid intersection points within the plane contour line;

[0108] (d) Map the mesh intersections within the planar contour to the filled surface to obtain the filled nodes.

[0109] (4) Figure 9 As shown, the normal vector m of the filled node on the filled surface is extracted. n2 and tangential vector m t2 The specific steps are as follows:

[0110] (a) Extract the normal vector m of the filled node on the filled surface. n2 ;

[0111] (b) Group the fill nodes and connect the fill nodes in the same group to obtain the fill curve;

[0112] (c) Extract the tangential vector m of the fill node along the fill curve direction. t2 .

[0113] (5) Figure 10As shown, grid lines are divided within the planar contour line according to the filling spacing of the filled unit cells. The intersections of the grid lines are then mapped to the filled surface to obtain the filled nodes. The specific steps are as follows:

[0114] (a) Using the center of the unit cell and the filling nodes as reference points, move the unit cell and copy it to all filling nodes;

[0115] (b) Rotate the filling unit cells so that the normal filling vector m of each unit cell is... n1 The normal vector m of the corresponding fill node on the fill surface n2 Overlap, that is:

[0116] m n1i =m n2i (i = 1, 2, ..., n) where n is the number of nodes to be filled.

[0117] (c) Rotate the filling unit cells again, so that the tangential filling vector m of each unit cell is... t1 The tangent vector m of the corresponding fill node on the fill curve t2 Overlap, that is:

[0118] m t1i =m t2i (i=1,2.....n)(6) Merge the filled unit cells to obtain an adaptive filling model of the irregular curved surface structure unit cell. After post-processing the model, set the processing parameters for additive manufacturing.

[0119] This involves repairing gaps, interfering shells, holes, damaged edges, overlaps, and intersecting triangular facets in an adaptive filling model of an irregular curved surface structure. Laser selective melting technology was used for shaping, with the processing laser power set to 60W, spot diameter to 0.05mm, slice thickness to 0.03mm, and biodegradable zinc metal used for additive manufacturing.

[0120] Example 3

[0121] like Figure 1 As shown, the present invention provides a method for conformal adaptive filling of porous unit cells for additive manufacturing of curved irregular parts, comprising the following steps:

[0122] (1) Body-centered cubic (BCC) was selected as the filling unit cell. Based on manufacturing process parameters, a parameterized model of the filling unit cell was constructed, with the structure as follows: Figure 5 As shown. Its boundary dimensions are 3.3mm × 3.3mm × 4.3mm, and the diameter of the support column is 0.4mm.

[0123] Among them, the shortest path filling vector n for the body-centered cubic is determined. t and the shortest path filling vector n t The shortest path fills the vector n tLet n be the vector representing the direction of the shortest path from one point in the unit cell to another, while the longest path fill vector is n. l This is the vector along the longest path from one point in the unit cell to another. In practical construction, an appropriate filling vector can be selected as needed. For example, by selecting the unit cell filling vector, the irregular curved surface filling structure can have a higher density or better structural performance in a certain direction.

[0124] (2) The selected irregular curved surface structure is Figure 6 The skull structure shown, such as Figure 7 As shown, the filled surface of the irregular curved surface structure is extracted, a baseline and a reference line are set, and the filled surface is unfolded in a plane to obtain a planar contour line;

[0125] The baseline is set on the filled surface, the reference line is set on the unfolded filled surface, the filled surface dataset is extracted, flattened and output as a planar contour line, and the envelope area of ​​the unfolded planar contour line is set to be consistent with the area of ​​the filled surface.

[0126] (3) Figure 8 As shown, grid lines are divided within the planar contour line according to the filling spacing of the filled unit cells. The intersections of the grid lines are then mapped to the filled surface to obtain the filled nodes. The specific steps are as follows:

[0127] (a) Extract the control points of the plane contour line, and at the same time extract the center point of the plane contour. Measure the distance between the center point and each control point on the plane contour line, take the maximum distance dm, and draw a rectangular border with 2*(dm+1) as the side length so that the rectangular border encloses the plane contour.

[0128] (b) Take points at equal intervals d1 = 4.3 and d2 = 3.3 in the horizontal and vertical directions of the rectangular border, respectively, connect the corresponding points to form grid lines, and obtain the grid intersections;

[0129] (c) Determine whether each grid intersection point is within the plane contour line and output the corresponding Boolean value, and retain the grid intersection points within the plane contour line;

[0130] (d) Map the mesh intersections within the planar contour to the filled surface to obtain the filled nodes.

[0131] (4) Figure 9 As shown, the normal vector m of the filled node on the filled surface is extracted. n2 and tangential vector m t2 The specific steps are as follows:

[0132] (a) Extract the normal vector m of the filled node on the filled surface. n2 ;

[0133] (b) Group the fill nodes and connect the fill nodes in the same group to obtain the fill curve;

[0134] (c) Extract the tangential vector m of the fill node along the fill curve direction. t2 .

[0135] (5) Figure 10 As shown, grid lines are divided within the planar contour line according to the filling spacing of the filled unit cells. The intersections of the grid lines are then mapped to the filled surface to obtain the filled nodes. The specific steps are as follows:

[0136] (a) Using the center of the unit cell and the filling nodes as reference points, move the unit cell and copy it to all filling nodes;

[0137] (b) Rotate the filling unit cells so that the normal filling vector m of each unit cell is... n1 The normal vector m of the corresponding fill node on the fill surface n2 Overlap, that is:

[0138] m n1i =m n2i (i = 1, 2, ..., n) where n is the number of nodes to be filled.

[0139] (c) Rotate the filling unit cells again, so that the tangential filling vector m of each unit cell is... t1 The tangent vector m of the corresponding fill node on the fill curve t2 Overlap, that is:

[0140] m t1i =m t2i (i=1,2.....n)(6) Merge the filled unit cells to obtain an adaptive filling model of the irregular curved surface structure unit cell. After post-processing the model, set the processing parameters for additive manufacturing.

[0141] This involves repairing gaps, interfering shells, holes, damaged edges, overlaps, and intersecting triangular facets in an adaptive filling model of an irregular curved surface structure. Laser selective melting technology was used for forming, with a laser power of 60W, a spot diameter of 0.05mm, a slice thickness of 0.03mm, and titanium alloy used for additive manufacturing.

[0142] The construction method of the angle-adaptive unit cell filling model for irregular structures is achieved by interconnecting the operators in Grasshopper. Therefore, this invention can easily achieve adaptive unit cell filling for various requirements by adjusting the parameters set on the operators, enabling adaptive unit cell filling for irregular curved structures of different shapes and achieving diversified designs of porous irregular curved structures. Furthermore, the controllability of various parameters of this type of lattice model is improved, and the boundary damage problem of conventional unit cell filling is avoided, ensuring the integrity of the lattice. This results in a more uniform stress distribution under load, further enhancing the mechanical strength of porous irregular structures.

[0143] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0144] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for conformal adaptive filling of porous unit cells for additive manufacturing of curved and irregularly shaped parts, characterized in that, Includes the following steps: S1. Construct the filled unit cell, set the filling spacing of the filled unit cell, and determine the normal filling vector m of the filled unit cell. n1 and tangential filling vector m t1 ; S2. Extract the filled surface of the irregular curved surface structure, set the baseline and reference line, and unfold the filled surface into a plane to obtain the plane contour line; S3. Divide grid lines within the planar contour line according to the filling spacing of the filling unit cells, and map the intersection of the grid lines to the filling surface to obtain the filling nodes. S4. Extract the normal vector m of the fill node on the fill surface. n2 and tangential vector m t2 ; S5. Perform adaptive filling of the filling unit cell, and set the normal filling vector m of the filling unit cell. n1 With the normal vector m of the filling node n2 Overlapping, tangential filling vector m of the filling unit cell t1 Tangential vector m of the filling node t2 coincide; S6. Merge the filled unit cells to obtain the irregular curved surface structure unit cell adaptive filling model, import the irregular curved surface structure unit cell adaptive filling model for post-processing, and set the processing parameters for additive manufacturing.

2. The method for adaptive filling of porous unit cells for additive manufacturing of irregularly shaped curved parts according to claim 1, characterized in that, In step S1, the filling unit cell includes one or more of the following: body-centered cubic, octahedral cubic, face-centered cubic, regular hexahedron, cubic octahedron, truncated octahedron, regular dodecahedron, rhombic dodecahedron, regular icosahedron, diamond, truncated hexagonal mosaic, small rhombic truncated cube, honeycomb, and foam.

3. The method for adaptive filling of porous unit cells for additive manufacturing of irregularly shaped curved parts according to claim 1, characterized in that, In step S1, the filling spacing includes a lateral spacing d1 and a longitudinal spacing d2. The filling spacing is designed according to the size of the filled unit cell to ensure the connectivity between units; the normal filling vector m n1 The normal filling vector m is the direction vector of the shortest side of the rectangle that fills the boundary of the unit cell. n2 Let be the direction vector of the longest side of the bounding rectangle of the filled unit cell.

4. The method for adaptive filling of porous unit cells for additive manufacturing of irregularly shaped curved parts according to claim 1, characterized in that, In step S2, the baseline is set on the filled surface, the reference line is set on the unfolded filled surface, the filled surface is flattened and a planar contour line is output, and the envelope area of ​​the unfolded planar contour line is set to be consistent with the area of ​​the filled surface.

5. The method for adaptive filling of porous unit cells for additive manufacturing of irregularly shaped curved parts according to claim 1, characterized in that, In step S3, grid lines are divided and fill nodes are obtained. The specific steps are as follows: S31. Extract the control points and center point of the planar contour line. Measure the distance between the center point and each control point on the planar contour line. Take the maximum distance dm. Draw a rectangular border with a side length of dm+x to ensure that the rectangular border completely encloses the planar contour. Here, x is a positive number and the unit of x is consistent with the unit of dm. S32. Take points at equal intervals d1 in the horizontal direction of the rectangular border and at equal intervals d2 in the vertical direction of the rectangular border. Connect the corresponding points to form grid lines, and calculate and obtain the grid intersections. S33. Determine whether each grid intersection point is within the plane contour line and output the corresponding Boolean value, and retain the grid intersection points within the plane contour line; S34. Map the mesh intersections within the planar contour to the filled surface to obtain the filled nodes.

6. The method for conformal adaptive filling of porous unit cells for additive manufacturing of irregularly shaped curved parts according to claim 1, characterized in that, In step S4, the normal vector m of the filling node on the filling surface is extracted. n2 and tangential vector m t2 The specific steps are as follows: S41. Extract the normal vector m of the fill node on the fill surface. n2 ; S42. Group the fill nodes and connect the fill nodes in the same group to obtain the fill curve; S43. Extract the tangential vector m of the fill node along the fill curve direction. t2 .

7. The method for adaptive filling of porous unit cells for additive manufacturing of irregularly shaped curved parts according to claim 1, characterized in that, In step S5, adaptive filling of the filling unit cells is performed, and the specific steps are as follows: S51. Using the center of the filled cell and the filled nodes as reference points, move the filled cell and copy it to all filled nodes; S52. Rotate the filled unit cells so that the normal filling vector m of each filled unit cell is... n1 The normal vector m of the corresponding fill node on the fill surface n2 Overlap, that is: m n1i =m n2i (i = 1, 2, ..., n) where n is the number of nodes to be filled; S53. Rotate the filling unit cells again, so that the tangential filling vector m of each filling unit cell is... t1 The tangent vector m of the corresponding fill node on the fill curve t2 Overlap, that is: m t1i =m t2i (i=1,2.....n)。 8. The method for conformal adaptive filling of porous unit cells for additive manufacturing of irregularly shaped curved parts according to claim 1, characterized in that, In step S6, processing parameters are set for additive manufacturing. The specific steps are as follows: The placement is based on the principle of minimum Z-axis height, and the support type is conical. Set the processing laser power, spot diameter, slice thickness, and tapered support parameters; Complete additive manufacturing.

9. The method for conformal adaptive filling of porous unit cells for additive manufacturing of irregularly shaped curved parts according to claim 1, characterized in that, In step S6, the additive manufacturing includes one of powder bed melting, binder spraying, material extrusion, material spraying, and photopolymerization molding.

10. The method for adaptive filling of porous unit cells for additive manufacturing of irregularly shaped curved parts according to claim 1, characterized in that, In step S6, the additive manufacturing material includes one of metals, polymers, ceramics, or a composite material thereof.

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