A meshing method for additive manufacturing of sliced multi-layer structures

Abstract

The embodiment of the application provides a grid division method for additive manufacturing slice type multilayer structure, which can solve the technical problem of poor grid division capability in the related art. The method comprises the following steps: dividing a surface grid on a first surface, and converting a second surface into a point cloud result. According to process constraints, matching grid nodes and surface nodes to obtain surface node pairs. In this way, not only the geometric shape is considered, but also the additive manufacturing layering process. According to the surface node pairs, based on a quadrilateral grid, layered hexahedron-based finite element units are divided, that is, a volume grid is generated through the surface grid. While achieving rapid grid division, the stability of various spatial surfaces is ensured, and a grid division algorithm with high automation degree, good stability and good grid quality is realized. The grid division is performed on the additive manufacturing slice type multilayer structure, the material direction and the layering direction are accurately specified, and the efficiency and accuracy of simulation calculation of the additive manufacturing slice type multilayer structure are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of additive manufacturing, and particularly relates to a grid division method for additive manufacturing slice type multi-layer structure. BACKGROUND

[0002] Additive manufacturing is a method of manufacturing physical parts by gradually accumulating materials. Using simulation analysis methods such as finite element analysis, finite difference, finite volume, physics-informed neural networks (PI NN), etc., the multi-physical field simulation of parts under additive manufacturing mode can be performed. In this way, not only can the design be optimized, the cost be reduced, and the reliability be improved, but also the complex structure innovation and intelligent manufacturing are supported, which has important scientific significance and engineering value. In addition, it provides a powerful tool for the wide application of additive manufacturing technology and promotes the digital transformation and innovative development of the manufacturing industry.

[0003] At present, the premise of various simulation analysis methods such as finite element analysis is to generate effective finite element grids. Through the base grid method, hexahedral grids can be generated for any input geometry, solving the limitations of traditional methods in dealing with complex geometry. The specific steps are divided into two steps: first, generate an initial cubic grid inside the design domain. This step ensures the uniformity and continuity of the grid through regularized segmentation. Then, the boundary region of the initial grid is projected onto the surface of the target geometry, and the position of the grid nodes is adjusted to fit the geometric boundary, thereby generating a complete hexahedral grid.

[0004] However, when dividing the grid of the additive manufacturing slice type multi-layer structure, problems such as poor grid quality, inconsistent cell direction with actual layer direction, etc. may occur. As a result, there is a large error between the calculation results of the finite element analysis and the actual situation. SUMMARY

[0005] The embodiment of the present application provides a grid division method for additive manufacturing slice type multi-layer structure, which can solve the technical problem of poor grid division capability in the related art.

[0006] To achieve the above-mentioned purpose, the embodiments of the present application adopt the following technical solutions:

[0007] In a first aspect, embodiments of this application provide a mesh generation method for additive manufacturing slice-type multilayer structures. This mesh generation method includes: identifying a first surface and a second surface; in a first direction, the first surface and the second surface are two opposing surfaces of a part to be simulated; dividing a quadrilateral mesh on the first surface to obtain mesh nodes; the quadrilateral mesh is a structured mesh; converting the second surface into a point cloud result; the point cloud result includes surface nodes; matching mesh nodes and surface nodes according to process constraints to obtain surface node pairs; generating intermediate nodes through interpolation based on the surface node pairs and the number of layers; the intermediate nodes are nodes on layers within the part to be simulated; dividing the layers into finite element units based on the quadrilateral mesh using the intermediate nodes to obtain a hexahedral mesh; identifying and deleting overlapping nodes of the hexahedral mesh according to preset node shrinkage conditions to obtain element shape results; the element shape results include finite element node coordinates; identifying wedge-shaped element results based on the element shape results; and obtaining a mesh generation result based on the hexahedral mesh and the wedge-shaped element results.

[0008] Based on the above description of the mesh generation method for additive manufacturing sliced ​​multilayer structures provided in this application embodiment, it can be seen that the mesh generation method for additive manufacturing sliced ​​multilayer structures includes obtaining mesh nodes on a first surface and converting the second surface into a point cloud result. According to process constraints, mesh nodes and surface nodes are matched to obtain surface node pairs. This considers not only the geometry but also the additive manufacturing layup process. Based on the surface node pairs, finite element elements, mainly hexahedral elements, are generated from the quadrilateral mesh, i.e., a volume mesh is generated through the surface mesh. This achieves rapid mesh generation while ensuring stability for various spatial curved surfaces, realizing a mesh generation algorithm with high automation, good stability, and high mesh quality. Meshing additive manufacturing sliced ​​multilayer structures is highly automated, robust to complex geometries, and the mesh direction has little difference from the actual material layup direction, allowing for precise specification of material and layup directions. This provides a more accurate finite element mesh for finite element analysis, improving the efficiency and accuracy of simulation calculations for multilayer additive manufacturing sliced ​​multilayer structures.

[0009] Furthermore, this application's embodiments, based on mesh generation of inner and outer surfaces, achieve rapid and highly controllable generation of volume meshes for additive manufacturing of slice-type multilayer structures. By generating uniform hexahedral meshes of equal and variable thickness, efficient surface slicing and simulation can be achieved for printers with arbitrary base plate shapes. This overcomes the current problems of slow calculation speed and complex, error-prone processing paths in printers handling some curved base plates. The mesh generation algorithm of this invention has a high degree of automation and fast calculation speed, which can simplify processing difficulty and reduce processing costs.

[0010] In the feasible implementation of the first aspect, when performing the step of confirming and deleting the overlapping nodes of the hexahedral mesh according to the preset node shrinkage conditions to obtain the element shape result; there are multiple layers; the mesh generation method for additive manufacturing slice-type multilayer structures also includes: in the first surface, the second surface and multiple layers, performing secondary node matching on the nodes of any two adjacent layers to obtain adjacent node pairs; deleting other nodes except for adjacent node pairs to obtain finite element node coordinates.

[0011] In the feasible implementation of the first aspect, when performing the step of confirming and deleting the overlapping nodes of the hexahedral mesh according to the preset node shrinkage condition to obtain the element shape result; there are multiple layers; the mesh generation method for additive manufacturing slice-type multilayer structures also includes: if the geometric distance between any two nodes on any layer is less than the preset shrinkage threshold, then the two nodes are shrunk into one node to obtain the finite element node coordinates.

[0012] In the feasible implementation of the first aspect, process constraints include geometric constraints and / or thickness constraints.

[0013] In a feasible implementation of the first aspect, the dimension of the first surface is greater than or equal to the dimension of the second surface in the first direction.

[0014] In the feasible implementation of the first aspect, when performing the step of dividing a quadrilateral mesh on the first surface to obtain mesh nodes, the meshing method for additive manufacturing slice-type multilayer structures further includes: optimizing the quadrilateral mesh division result according to the surface shape and / or mesh requirements.

[0015] In the feasible implementation of the first aspect, when performing the step of matching mesh nodes and surface nodes according to process constraints to obtain surface node pairs, the mesh generation method for additive manufacturing slice-type multilayer structures further includes: obtaining surface node pairs according to a K-dimensional tree algorithm.

[0016] In the feasible implementation of the first aspect, the part to be simulated includes irregularly shaped parts.

[0017] In a second aspect, embodiments of this application provide a mesh generation system for additive manufacturing slicing multilayer structures. The mesh generation system for additive manufacturing slicing multilayer structures includes: at least one processor; a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method provided in the first aspect.

[0018] The meshing system for additive manufacturing slice-type multilayer structures executes the method provided in the first aspect to generate a surface mesh on the first surface and convert the second surface into a point cloud. Based on process constraints, mesh nodes and surface nodes are matched to obtain surface node pairs. This considers not only the geometry but also the additive manufacturing layup process. Based on the surface node pairs, layered hexahedral finite element elements are generated from the quadrilateral mesh to obtain a hexahedral mesh, i.e., generating a volume mesh from the surface mesh. This achieves rapid mesh generation while ensuring stability for various spatial curved surfaces, realizing a highly automated, stable, and high-quality mesh generation algorithm. Meshing additive manufacturing slice-type multilayer structures is highly automated, robust to complex geometries, and the mesh orientation has minimal difference from the actual material layup orientation, allowing for precise specification of material and layup directions. This provides a more accurate finite element mesh for finite element analysis, improving the efficiency and accuracy of simulation calculations for multilayer additive manufacturing slice-type multilayer structures.

[0019] Thirdly, embodiments of this application provide a computer-readable medium having computer program instructions stored thereon, which can be executed by a processor to implement the method provided in the first aspect.

[0020] Computer program instructions in a computer-readable medium, by implementing the method provided in the first aspect, divide a surface mesh on a first surface and convert a second surface into a point cloud result. According to process constraints, mesh nodes and surface nodes are matched to obtain surface node pairs. This considers not only the geometry but also the additive manufacturing layup process. Based on the surface node pairs, layered hexahedral-dominated finite element elements are divided using a quadrilateral mesh to obtain a hexahedral mesh, i.e., a volume mesh is generated from the surface mesh. This achieves rapid mesh generation while ensuring stability for various spatial curved surfaces, realizing a highly automated, stable, and high-quality mesh generation algorithm. Meshing additively manufactured slice-type multilayer structures exhibits a high degree of automation, strong robustness to complex geometries, and minimal difference between the mesh direction and the actual material layup direction. It allows for precise specification of material and layup directions, thus providing a more accurate finite element mesh for finite element analysis and improving the efficiency and accuracy of simulation calculations for multilayer additively manufactured slice-type multilayer structures. Attached Figure Description

[0021] Figure 1 A schematic diagram of a mesh generation system for additive manufacturing slice-type multilayer structures provided in this application embodiment;

[0022] Figure 2 A flowchart illustrating a mesh generation method for additive manufacturing of sliced ​​multilayer structures provided in this application embodiment;

[0023] Figure 3 This is a schematic diagram of the structure of the part to be simulated in a mesh generation method for additive manufacturing sliced ​​multilayer structures provided in an embodiment of this application;

[0024] Figure 4 This is a schematic diagram of the structure of the part to be simulated in a mesh generation method for additive manufacturing sliced ​​multilayer structures provided in an embodiment of this application;

[0025] Figure 5 This is a schematic diagram of the structure of the part to be simulated in a mesh generation method for additive manufacturing sliced ​​multilayer structures provided in an embodiment of this application;

[0026] Figure 6a for Figure 3 The diagram shows the division of the first surface in the part to be simulated;

[0027] Figure 6b for Figure 4 The diagram shows the division of the first surface in the part to be simulated;

[0028] Figure 7a for Figure 3 The diagram shows the division of the second surface in the part to be simulated;

[0029] Figure 7b for Figure 4 The diagram shows the division of the second surface in the part to be simulated;

[0030] Figure 8 This is a schematic diagram of the structure of the intermediate node in a mesh generation method for additive manufacturing sliced ​​multilayer structures provided in an embodiment of this application;

[0031] Figure 9 This is a schematic diagram of the layered structure in a mesh generation method for additive manufacturing sliced ​​multilayer structures provided in an embodiment of this application;

[0032] Figure 10 This is a schematic diagram of node shrinkage in a mesh generation method for additive manufacturing sliced ​​multilayer structures provided in an embodiment of this application;

[0033] Figure 11a for Figure 3 The diagram shows the mesh generation result of the part to be simulated;

[0034] Figure 11b for Figure 4 The diagram shows the mesh generation result of the part to be simulated. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be described below with reference to the accompanying drawings. In the description of the embodiments of the present invention, unless otherwise stated, "multiple" refers to two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of a single item or a plurality of items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0036] Furthermore, to facilitate a clear description of the technical solutions in the embodiments of the present invention, the terms "first" and "second" are used to distinguish identical or similar items with substantially the same function and effect. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and that "first" and "second" are not necessarily different. Meanwhile, in the embodiments of the present invention, the terms "exemplary" or "for example" are used to indicate that something is being used as an example, illustration, or description. Any embodiment or design scheme described as "exemplary" or "for example" in the embodiments of the present invention should not be construed as being more preferred or advantageous than other embodiments or design schemes. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner for ease of understanding.

[0037] The principles and features of this application are described below. The examples given are only for explaining this application and are not intended to limit the scope of this application.

[0038] In a broad sense, additive manufacturing encompasses various composite material additive manufacturing technologies based on the melt curing and sintering of powders, filaments, and sheets, continuous fiber additive printing, Automated Fiber Placement (AFP), and Automated Tow Placement (ATP).

[0039] Rotational layering (or rotational deposition) in additive manufacturing typically refers to changing the material layup direction by rotating the material at different angles during 3D printing or additive manufacturing to optimize structural properties or create complex geometries. In composite additive manufacturing (such as continuous fiber reinforced 3D printing), rotational layering can be used to: enhance mechanical properties by optimizing strength, stiffness, and impact resistance through layup at different angles (e.g., 0°, 45°, or 90°); reduce material anisotropy by laying material in different directions to improve overall uniformity; and adapt to complex curved surfaces by better adapting to curved structures and reducing stress concentration.

[0040] The k-dimensional tree algorithm (KD-Tree algorithm), also known as the k-dimensional space partitioning tree algorithm, is where "k" represents the dimension of the data, and "tree" indicates that the data structure is a tree structure.

[0041] This application provides a mesh generation method for additive manufacturing sliced ​​multilayer structures, applicable to aerospace, defense, transportation, and other related fields. The hexahedral-based mesh generated in this application can be flexibly adapted to various needs, including finite element analysis, additive manufacturing, 3D modeling, surface slicing, mesh rendering, and optimization design.

[0042] For example, embodiments of this application can be used in the field of rendering. By efficiently and automatically dividing complex geometries into hexahedral meshes, the structural geometric details are preserved while the node storage is reduced, making the rendering of complex geometries faster and reducing the demand for mesh calculation and data storage, thereby providing more options for animation, movie special effects, games and other fields.

[0043] The orientation of the divided mesh can be adjusted to better simulate the reflection of light on the surface of an object, enabling advanced rendering techniques such as ray tracing and global illumination, and improving the realism of the rendering.

[0044] This application provides a mesh generation system for additive manufacturing sliced ​​multilayer structures, which can execute the mesh generation method for additive manufacturing sliced ​​multilayer structures provided in this application. Figure 1 This is a schematic diagram of a mesh generation system for additive manufacturing slice-type multilayer structures provided in an embodiment of this application.

[0045] like Figure 1 As shown, the additive manufacturing slice-type multilayer structure mesh generation system 001 includes at least one processor 011 and a memory 012 communicatively connected to the at least one processor; wherein, the memory 012 stores instructions that can be executed by the at least one processor 011, and the instructions are executed by the at least one processor 011 to enable the at least one processor 011 to execute the additive manufacturing slice-type multilayer structure mesh generation method provided in the embodiments of this application.

[0046] Figure 2 This is a flowchart illustrating a mesh generation method for additive manufacturing of sliced ​​multilayer structures, provided in an embodiment of this application. Figure 2 As shown, in some embodiments, the mesh generation method for this additive manufacturing sliced ​​multilayer structure includes the following steps:

[0047] S1, confirm the first surface and the second surface.

[0048] In the first direction, the first surface and the second surface are two opposing surfaces of the part to be simulated.

[0049] The part to be simulated is manufactured using additive manufacturing. The manufacturing process involves a slicing, multi-layered structure. For example... Figure 3 The layer thickness of the simulated part varies with its geometric position. For example... Figure 4 The layer thickness of the simulated part shown is kept constant.

[0050] The shape of the part to be simulated can be varied. For example, it can be a regular geometric shape (such as a tetrahedron or a cylinder). Or, for example, it can be... Figure 3 or Figure 4 The irregularly shaped part shown.

[0051] The first surface, also known as the outer surface, is the outermost surface of the grid and can be used as the bottom surface for additive manufacturing of slice-type multilayer structures.

[0052] The second surface, also known as the inner surface.

[0053] like Figure 3 or Figure 4 As shown, in some embodiments, in a first direction, the dimension of the first surface is greater than or equal to the dimension of the second surface. That is, the geometry of the outer surface should be greater than or equal to that of the inner surface.

[0054] Understandable Figure 3 or Figure 4 This example only illustrates one possible implementation of the first direction and does not constitute a limitation on the first direction. For any part to be simulated, the first direction is arbitrary.

[0055] For example, such as Figure 5 As shown, the first direction can be horizontal (with the ground as a reference).

[0056] S2, divide the first surface into quadrilateral grids to obtain grid nodes.

[0057] In some embodiments, quadrilateral meshes can be divided on the first surface using methods such as sweeping, front advancement, octree, merging triangles, or region segmentation, or using various meshing software.

[0058] Quadrilateral grid, such as Figure 6a or Figure 6b As shown, this is a structured mesh. That is, when dividing the outer surface into quadrilateral meshes, the orientation of the mesh is consistent with the actual material orientation.

[0059] Understandable Figure 6a or Figure 6bThe example provided is merely one feasible implementation of a quadrilateral mesh and does not constitute a limitation on the number or size of the quadrilateral mesh.

[0060] To obtain better meshing results, in some embodiments, the actual meshing effect of the quadrilateral mesh is adjusted according to geometric factors. This results in a more accurate meshing outcome generated based on the quadrilateral mesh on the first surface.

[0061] In some embodiments, the mesh generation method for additive manufacturing sliced ​​multilayer structures further includes the following when performing step S2:

[0062] S21, optimize the quadrilateral mesh division result based on the surface shape and / or mesh requirements.

[0063] S3 converts the second surface into a point cloud result.

[0064] In some embodiments, the second surface is converted into a point cloud result by methods such as random sampling, uniform sampling, or grid node extraction.

[0065] Point cloud results, such as Figure 7a or Figure 7b As shown, this includes surface nodes.

[0066] To ensure the accuracy of subsequent node identification, a higher point cloud density is used in some embodiments.

[0067] S4. Based on process constraints, match mesh nodes and surface nodes to obtain surface node pairs.

[0068] In some embodiments, process constraints include geometric constraints and / or thickness constraints, etc.

[0069] In some embodiments, when performing step S4, the mesh generation method for additive manufacturing sliced ​​multilayer structures further includes:

[0070] S41, according to the K-dimensional tree algorithm, obtain the surface node pairs.

[0071] In some embodiments, during the identification process, corresponding geometric constraints, such as horizontal and vertical constraints, can be set according to the actual layup process to make the surface node pairs approximate the actual situation. By establishing the correspondence between nodes between inner and outer surface meshes through the KD-Tree algorithm, not only can a solid mesh dominated by hexahedrons be grown from the surface mesh, but the effect of node merging can also be achieved through the update iteration of the nearest points between multiple layers.

[0072] In other embodiments, the method for obtaining surface node pairs, i.e., establishing the correspondence between inner and outer surface nodes, can also be the outer surface perpendicular line method, the element normal vector translation method, or the surface mapping method.

[0073] S5 generates intermediate nodes through interpolation based on surface node pairs and the number of ply layers.

[0074] like Figure 8 As shown, intermediate nodes are associated with surface nodes.

[0075] Intermediate nodes are the internal nodes of the part to be simulated, such as... Figure 9 The nodes on any of the layers shown.

[0076] S6, based on the intermediate nodes, divide the finite element into layers based on the quadrilateral mesh to obtain a hexahedral mesh.

[0077] S7. Based on the preset node shrinkage conditions, confirm and delete the overlapping nodes of the hexahedral mesh to obtain the element shape result.

[0078] The element shape results include finite element node coordinates.

[0079] In some embodiments, when performing step S7, there are multiple layers, and the mesh generation method for additive manufacturing slice-type multilayer structures further includes:

[0080] S711, in the first surface, the second surface and multiple layers, perform secondary node matching on any two adjacent layers to obtain adjacent node pairs.

[0081] S712, delete all nodes except adjacent node pairs to obtain the finite element node coordinates.

[0082] In other embodiments, when performing step S7, there are multiple layers, and the mesh generation method for additive manufacturing slice-type multilayer structures further includes:

[0083] S721, if the geometric distance between any two nodes on any layer is less than the preset shrinkage threshold, then the two nodes are shrunk into one node to obtain the finite element node coordinates.

[0084] like Figure 10 As shown, an exemplary feasible implementation of the contraction is given, in which the nodes in the dashed box are deleted.

[0085] It is understandable that the finite element is primarily composed of hexahedral elements. Because pure hexahedral elements may have issues such as poor quality, a node reduction process is added after obtaining the hexahedral mesh to remove some of the poor-quality hexahedral elements (such as…). Figure 10 The deleted nodes shown are shrunk into wedge-shaped elements and other elements to ensure element quality.

[0086] S8, based on the element shape results, confirm the wedge element results.

[0087] S9. Based on the results of hexahedral elements and wedge elements, the mesh generation result is obtained.

[0088] In some embodiments, based on the number of mesh nodes, the obtained hexahedral and wedge-shaped elements are automatically identified and classified, the node numbering order is updated, and different element types are used for calculation to improve mesh quality and calculation accuracy.

[0089] In some embodiments, the mesh classification method can also be based on surface mesh classification, cell node coordinate classification, cell number classification, etc.

[0090] In some embodiments, hexahedral elements and wedge elements are written into a mesh file in a common format such as an ACS II text file for output, resulting in a mesh file like... Figure 11a or Figure 11b The grid division result is shown.

[0091] Based on the same concept, this application also provides a mesh generation system for additive manufacturing sliced ​​multilayer structures. The method corresponding to the mesh generation system for additive manufacturing sliced ​​multilayer structures can be the mesh generation method for additive manufacturing sliced ​​multilayer structures in the aforementioned embodiments, and its problem-solving principle is similar to that method. The mesh generation system for additive manufacturing sliced ​​multilayer structures provided in this application includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the methods and / or technical solutions of the various embodiments of this application.

[0092] Another embodiment of this application provides a computer-readable storage medium having computer program instructions stored thereon, which can be executed by a processor to implement the methods and / or technical solutions of any one or more embodiments of this application described above.

[0093] Specifically, this embodiment may employ any combination of one or more computer-readable media. A computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. A computer-readable storage medium may be, for example,—but not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of computer-readable storage media (a non-exhaustive list) include: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this document, a computer-readable storage medium may be any tangible medium that contains or stores a program that can be used by or in connection with an instruction execution system, apparatus, or device.

[0094] Computer-readable signal media may include data signals propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals may take various forms, including—but not limited to—electromagnetic signals, optical signals, or any suitable combination thereof. Computer-readable signal media may also be any computer-readable medium other than computer-readable storage media, capable of sending, propagating, or transmitting programs for use by or in connection with an instruction execution system, apparatus, or device.

[0095] The program code contained on a computer-readable medium may be transmitted using any suitable medium, including—but not limited to—wireless, wire, optical fiber, RF, etc., or any suitable combination thereof.

[0096] Computer program code for performing the operations of this application can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Python, and C++, and conventional procedural programming languages ​​such as C, MATLAB, or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0097] The flowcharts or block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of devices, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-specific system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0098] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0099] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or page components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between devices or units through some interfaces, and may be electrical, mechanical, or other forms.

[0100] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0101] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or in a combination of hardware and software functional units.

[0102] The integrated units implemented as software functional units described above can be stored in a computer-readable storage medium. These software functional units, stored in a storage medium, include several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) or processor to execute some steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0103] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

[0104] Furthermore, it is clear that the word "comprising" does not exclude other units or steps, and the singular does not exclude the plural. Multiple units or devices recited in a device claim may also be implemented by a single unit or device through software or hardware. The terms "first," "second," etc., are used to indicate names and do not indicate any specific order.

Claims

1. A mesh generation method for additive manufacturing slice-type multilayer structures, characterized in that, include: Identify the first and second surfaces; In the first direction, the first surface and the second surface are two opposing surfaces of the part to be simulated; Divide the first surface into quadrilateral grids to obtain grid nodes; The quadrilateral grid is a structured grid; The second surface is converted into a point cloud result; the point cloud result includes surface nodes; Based on process constraints, the mesh nodes and the surface nodes are matched to obtain surface node pairs; Based on the surface node pairs and the number of ply layers, intermediate nodes are generated through interpolation. The intermediate node is a node on a layer inside the part to be simulated; Based on the intermediate nodes and the quadrilateral mesh, the layered finite element units are divided to obtain a hexahedral mesh; Based on the preset node shrinkage conditions, the overlapping nodes of the hexahedral mesh are confirmed and deleted to obtain the unit shape result; The element shape result includes finite element node coordinates; Based on the unit shape results, the wedge-shaped unit results are confirmed; Based on the hexahedral mesh and the wedge-shaped element results, the mesh division result is obtained.

2. The mesh generation method for additive manufacturing sliced ​​multilayer structures according to claim 1, characterized in that, When performing the step of confirming and deleting the overlapping nodes of the hexahedral mesh according to the preset node shrinkage condition to obtain the unit shape result; There are multiple layers; The mesh generation method for additive manufacturing sliced ​​multilayer structures also includes: In the first surface, the second surface, and the plurality of layers, a secondary node matching is performed on any two adjacent layers to obtain adjacent node pairs; Delete all nodes except the adjacent node pairs to obtain the finite element node coordinates.

3. The mesh generation method for additive manufacturing sliced ​​multilayer structures according to claim 1, characterized in that, When performing the step of confirming and deleting overlapping nodes of the hexahedral mesh according to preset node shrinkage conditions to obtain the element shape result; there are multiple layers; the mesh generation method for additive manufacturing slice-type multilayer structures further includes: If the geometric distance between any two nodes on any layer is less than a preset shrinkage threshold, then the two nodes are shrunk into one node to obtain the finite element node coordinates.

4. The mesh generation method for additive manufacturing sliced ​​multilayer structures according to any one of claims 1-3, characterized in that, The process constraints include geometric constraints and / or thickness constraints.

5. The mesh generation method for additive manufacturing sliced ​​multilayer structures according to any one of claims 1-3, characterized in that, In a first direction, the size of the first surface is greater than or equal to the size of the second surface.

6. The mesh generation method for additive manufacturing sliced ​​multilayer structures according to any one of claims 1-3, characterized in that, When performing the step of dividing the first surface into quadrilateral grids to obtain grid nodes; The mesh generation method for additive manufacturing sliced ​​multilayer structures also includes: The quadrilateral mesh division result is optimized based on the surface shape and / or mesh requirements.

7. The mesh generation method for additive manufacturing sliced ​​multilayer structures according to any one of claims 1-3, characterized in that, When performing the step of matching the mesh nodes and the surface nodes according to process constraints to obtain surface node pairs, the mesh generation method for additive manufacturing sliced ​​multilayer structures further includes: The surface node pairs are obtained using the K-dimensional tree algorithm.

8. The mesh generation method for additive manufacturing sliced ​​multilayer structures according to any one of claims 1-3, characterized in that, The parts to be simulated include irregularly shaped parts.

9. A mesh generation system for additive manufacturing slice-type multilayer structures, characterized in that, include: At least one processor; A memory that is communicatively connected to the at least one processor; The memory stores instructions that can be executed by the at least one processor to enable the at least one processor to perform the method of any one of claims 1 to 8.

10. A computer-readable medium having stored thereon computer program instructions that can be executed by a processor to implement the method as described in any one of claims 1 to 8.

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