Three-dimensional curved beam slab unit and mixed point lattice structure thereof

Abstract

The application discloses a three-dimensional curved surface beam plate unit and a mixed point array structure thereof. The unit comprises an outer frame and a BCC framework, the BCC framework is located in the unit and is connected with the outer frame through nodes; the outer frame comprises symmetrically arranged upper curved surface plates and lower curved surface plates, and one recessed curved beam rod is arranged between the four corners of the upper and lower curved surface plates, so that the outer frame forms a concave structure; the BCC framework is composed of eight inclined beam rods, the inner ends of the eight inclined beam rods are connected with each other and located at the center point of the unit, and the outer ends of the eight inclined beam rods are connected with the four corners of the upper and lower curved surface plates respectively. The point array structure is composed of a plurality of periodically arranged units. The application fuses various elements of curved surface, beam and plate and realizes multi-level design to obtain a controllable mixed point array structure with light weight, high strength, high heat dissipation efficiency, impact resistance, vibration reduction and noise reduction.

Description

Technical Field

[0001] This invention belongs to the field of engineering structure technology, specifically relating to a three-dimensional curved beam-plate unit cell and its hybrid lattice structure. Background Technology

[0002] A lattice structure is a porous structure composed of tiny, periodically or non-periodically arranged unit cells in three-dimensional space. It possesses advantages such as high specific strength, specific stiffness, and energy absorption efficiency, and is widely used in aerospace, biomedicine, high-end industry, and automotive fields. Based on the geometric structure of the unit cells, lattices can be classified into beam lattices, plate lattices, and shell lattices.

[0003] Beam-type lattice unit cells, composed of rod-like structures, offer high specific stiffness, but are prone to stress concentration at nodes, resulting in poor stability and a high risk of member buckling. Plate-type lattice unit cells, composed of sheet-like structures, primarily bear in-plane loads, exhibiting high stability and shear resistance, but are relatively heavy and have lower material efficiency. Shell-type lattice unit cells, composed of curved surfaces, possess smooth and continuous surfaces, which helps reduce stress concentration, but are extremely difficult to manufacture.

[0004] CN202110911799.X discloses "A Honeycomb-Shaped Regular Hexagonal Lattice Material Structure," which is a typical beam-type lattice. CN202110080450.6 discloses "A Reinforced Unit Cell Structure and Its Preparation Method and Application, Sandwich Panel," which sets an octagonal lattice structure on the outside of a BCC body-centered cubic lattice structure to form a reinforced unit cell structure. While the preceding patents are also generally beam-type lattices, this structure mainly relies on external reinforcement members, and there is still room for improvement in terms of nodal stress distribution and multi-directional load-bearing capacity.

[0005] In summary, while lattice structures with single geometric shapes each have their advantages, their performance is relatively limited, their functions are restrictive, and they are poorly adaptable to complex working conditions, making it difficult to meet the demands of modern high-end equipment for "lightweight, multifunctional, and high-performance" structures. Therefore, it is essential to invent a high-performance, multifunctional curved beam-plate hybrid lattice structure to address these issues. Summary of the Invention

[0006] The technical problem to be solved by this invention is to provide a three-dimensional curved beam-plate unit cell and its hybrid lattice structure that combines the advantages of curved surfaces, beams, and plates.

[0007] To solve the above-mentioned technical problems, the technical solution of the present invention is: A three-dimensional curved beam-plate unit cell includes an outer frame and a BCC skeleton. The BCC skeleton is located inside the unit cell and is connected to the outer frame through nodes. The outer frame includes symmetrically arranged upper and lower curved panels. A concave curved beam is provided between each of the four corners of the upper and lower curved panels, thereby forming a concave structure of the outer frame. The BCC skeleton is composed of 8 diagonal beams. The inner ends of the 8 diagonal beams are connected to each other and located at the center point of the unit cell. The outer ends of the diagonal beams are respectively connected to the four corners of the upper and lower curved panels.

[0008] Preferably, a vertical straight beam is further provided, which passes through the center point of the unit cell and connects the upper and lower curved panels.

[0009] Preferably, the outer ends of the eight diagonal beams of the BCC frame are also connected to four reinforcing straight beams, which are respectively parallel to or connected to the straight edges on both sides of the upper and lower curved panels.

[0010] Preferably, the curvature of the curved beam is a sine curve.

[0011] Preferably, the curved surface curves of the upper and lower curved panels are circular arcs, parabolas, spline curves, or other function curves.

[0012] A three-dimensional curved beam-plate unit cell hybrid lattice structure is formed by the periodic arrangement of the aforementioned unit cells.

[0013] Preferably, the lattice structure is a three-dimensional curved beam-plate-SC hybrid lattice structure, which is a flat plate structure formed by arranging a single cell of the three-dimensional curved beam-plate on the XY plane, YZ plane and XZ plane of the three-dimensional rectangular coordinate system, and the flat plate structures of each plane intersect each other, sharing a single cell at the intersection, and finally obtaining a three-dimensional curved beam-plate-SC hybrid lattice structure composed of three mutually perpendicular flat plate lattice components.

[0014] Preferably, the lattice structure is a three-dimensional curved beam-plate-BCC hybrid lattice structure, which is generally a cuboid structure. Specifically, a unit cell of the three-dimensional curved beam-plate is placed at one vertex of the cuboid and arrayed along one side of the cuboid to the other vertex of that side. Then, the unit cells of the previous vertex are arrayed along the two face diagonals and one body diagonal connected to that side, until the center of each diagonal. Then, the unit cells of the other vertex are also arrayed along the two face diagonals and one body diagonal connected to that side, until the center of each diagonal. Finally, the unit cells on the body diagonal are filled to the two adjacent face diagonals, and the filling process does not change the orientation of the unit cells, thus obtaining structure A. Each side of the cuboid structure obtains a structure A through the above spatial lattice method, thus forming a three-dimensional curved beam-plate-BCC hybrid lattice structure. If the unit cells of adjacent structures A overlap, they share a single unit cell.

[0015] Preferably, the lattice structure is a three-dimensional curved beam-plate-FCC hybrid lattice structure, specifically: a unit cell of the three-dimensional curved beam is placed at the vertex of a cube, and the direction of one side of the cube connected to the vertex is the Z direction of the rectangular coordinate system, and the directions of the other two sides are the X and Y directions, respectively; the unit cell of the vertex is arrayed M times along the body diagonal and the mirror body diagonal direction connected to the vertex, for a total of M rows, and the mirror body diagonal is obtained by mirroring the body diagonal with the YZ plane; then the first row of the body diagonal... The cells are arrayed N times along the Z direction. The cells in the i-th row are arrayed N-2i-2 times along the Z direction, where i = 1, 2, ..., M, N ≥ 2M. The cells in the M-th row are arrayed 2 times along the Z direction, thus forming two symmetrical panels. Then, the cells are added in the X direction between the two panels to form structure H. Each edge of the upper and lower faces of the cube is obtained through the above spatial lattice method to form a structure H, for a total of 8 structures H, finally resulting in a three-dimensional curved beam-plate-FCC hybrid lattice structure. If the cells of adjacent structures H overlap, they share a cell.

[0016] Preferably, in the lattice structure, the orientation of each unit cell within each structure is the same, while the orientation of unit cells between different structures is different.

[0017] After adopting the above scheme, the three-dimensional curved beam-plate hybrid lattice structure of the present invention is composed of multiple identical unit cells arranged periodically. Each unit cell consists of two curved panels, one BCC unit cell, four curved beam rods, and five straight beam rods (i.e., one vertical straight beam rod connecting the centers of the upper and lower curved panels, and four reinforcing straight beam rods arranged parallel to or connected to the straight edges of the upper and lower curved panels). The two opposing curved panels constitute the load-bearing upper and lower surfaces of the unit cell. A BCC unit cell located at the geometric center of the unit cell serves as the core load-bearing skeleton. The four curved beam rods connect corresponding corner points of the upper and lower curved panels, forming the unit cell's outer frame together with the upper and lower curved panels. Of the five straight beam rods, four connect in pairs to the upper and lower ends of the curved beam rods on the sides of the unit cell to enhance lateral stability; the other vertically connects to the centers of the upper and lower curved panels to enhance internal stability.

[0018] The unit cell can be imagined as a concave cube with a node at each of its eight corners. The BCC framework inside the unit cell connects the node at the center of the cube to each of the eight corner nodes using a beam. Furthermore, the straight beam connecting the upper and lower curved panels of the unit cell passes through the node at the center of the cube.

[0019] The aforementioned three-dimensional curved beam-plate unit cell hybrid lattice structure is formed by the above-mentioned unit cells arranged in a three-dimensional space in the topological periodic arrangement of spatial lattice elements such as simple cube (SC), body-centered cube (BCC), and face-centered cube (FCC), successfully integrating curved surface, plate, curved beam and straight beam elements into one.

[0020] Specifically, the present invention has the following beneficial effects: 1. This invention integrates multiple elements such as curved surfaces, beams, and plates, and employs multi-level design to obtain an adjustable hybrid lattice structure with lightweight, high strength, efficient heat dissipation, impact resistance, and vibration and noise reduction capabilities. Specifically: (1) Lightweight and high strength: The composite load-bearing system is composed of curved shell plate and BCC frame. The curved structure can effectively disperse the out-of-plane load, and the BCC frame provides internal support, which can significantly reduce the weight of the structure while maintaining high specific strength and specific stiffness.

[0021] (2) High efficiency heat dissipation: The open porous structure forms a continuous fluid channel, which, combined with the large specific surface area of ​​the curved panel, significantly enhances the convective heat transfer efficiency and is suitable for active cooling or passive heat dissipation scenarios.

[0022] (3) Impact resistance: The curved beam and the curved panel deform together, and can absorb a large amount of energy through elastic bending and plastic deformation when subjected to impact; the BCC skeleton provides multi-directional force transmission path to avoid local failure leading to overall damage.

[0023] (4) Vibration reduction and noise reduction: The multi-level structure of curved surface-beam-plate forms an interface with impedance discontinuity, which increases the reflection and scattering path of vibration waves when they propagate inside the structure; the porous feature can effectively suppress the propagation of mid-to-high frequency noise.

[0024] (5) In this invention, the curvature and thickness of the curved panel, the cross-sectional dimensions of the curved beam and the straight beam, the geometric parameters of the BCC skeleton, and the spatial arrangement of the unit cell (SC / BCC / FCC) can all be adjusted independently, thereby realizing the on-demand design of the structural specific stiffness, energy absorption efficiency, heat dissipation performance and vibration transmission characteristics, and meeting the multi-functional integration requirements under different working conditions.

[0025] 2. By adjusting variables such as the curvature and thickness of the curved panel and the dimensions of the curved / straight beam, this invention can precisely "adjust" the mechanical, thermal, and acoustic properties of the structure to meet specific application requirements.

[0026] 3. Compared to CN202110080450.6, this invention constructs a multi-level stabilization system with internal and external coordination through the internal BCC skeleton, the reinforcing straight beams connecting the sides, and the central vertical straight beams. This forms a highly redundant force transmission network, which not only effectively prevents the curved panel and the overall structure from buckling and becoming unstable under pressure, avoiding the risk of sudden collapse, but also achieves higher ultimate bearing capacity and structural reliability at a lower mass cost. It is especially suitable for fields with high reliability requirements such as aerospace and aviation. Attached Figure Description

[0027] Figure 1 This is a three-dimensional view of the unit cell of the three-dimensional curved beam-plate described in this invention; Figure 2 This is a front view of the three-dimensional curved beam-plate unit cell described in this invention; Figure 3 This is a left view of the three-dimensional curved beam-plate unit cell described in this invention; Figure 4 This is a top view of the three-dimensional curved beam-plate unit cell described in this invention; Figure 5 This is a three-dimensional view of the first embodiment of the lattice structure described in this invention (three-dimensional curved beam-plate unit cell-SC hybrid). Figure 6 This is a schematic diagram of the formation structure of the first embodiment of the lattice structure described in this invention; Figure 7 This is a perspective view of the second embodiment of the lattice structure described in this invention (three-dimensional curved beam-plate unit cell-BCC hybrid). Figure 8 This is a schematic diagram of the formation structure of the second embodiment of the lattice structure described in this invention; Figure 9 This is a perspective view of the third embodiment of the lattice structure described in this invention (three-dimensional curved beam-plate unit cell-FCC hybrid). Figure 10 This is a schematic diagram of the formation structure of the third embodiment of the lattice structure described in this invention. Detailed Implementation

[0028] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0029] This invention discloses a three-dimensional curved beam-plate unit cell, such as... Figures 1-4 The diagram shows a preferred embodiment of the unit cell. The three-dimensional curved beam-plate unit cell 1 includes an outer frame 11 and a BCC skeleton 12, which is located inside the unit cell and connected to the outer frame 11 via nodes. Wherein: The external frame 11 includes symmetrically arranged upper curved panels 111 and lower curved panels 112. A concave curved beam 113 is provided between each of the four corners of the upper and lower curved panels, thus forming a concave structure for the external frame 11. The curved surfaces of the upper and lower curved panels 111 and 112 are not specifically limited; they can be circular arcs, parabolas, spline curves, or other function curves. The curvature of the curved beam 113 can be a sine curve. The advantages of a sine curve are: 1. Smooth transition: The curvature of a sine curve changes continuously without abrupt changes, significantly reducing stress concentration. 2. Strong buckling resistance: Compared to circular arcs or straight lines, sine curves can distribute load more evenly under compression, delaying local buckling. 3. Facilitates parametric design: Sine curves can be accurately described using parameters such as amplitude and period, facilitating structural optimization and performance control.

[0030] The BCC skeleton 12 is composed of 8 diagonal beams 121. The inner ends of the 8 diagonal beams 121 are connected to each other and located at the center point of the unit cell. The outer ends of the diagonal beams 121 are respectively connected to the four corners of the upper and lower curved panels 111 and 112.

[0031] To further increase strength, a vertical straight beam 3 can be added, which passes through the center point of the unit cell and connects the upper and lower curved panels 111 and 112.

[0032] Furthermore, the outer ends of the eight diagonal beams 121 of the BCC skeleton 12 are simultaneously connected to the upper and lower curved panels 111 and 112 and the four curved beams 113, forming the apex nodes of the unit cell. At this point, the loads along the straight edges of the two curved panels are all borne by the straight edges of the curved panels, which can easily cause local buckling at the edges of the curved panels. To avoid this problem, four reinforcing straight beams 114 can be added to the outer ends of the eight diagonal beams 121. These four reinforcing straight beams 114 are respectively arranged side-by-side or connected to the straight edges on both sides of the upper and lower curved panels 111 and 112. The advantages of adding four reinforcing straight beams 114 are: 1. Enhanced lateral stiffness: As independent components, the reinforcing straight beams 114 can use larger cross-sections or higher-strength materials, significantly improving the structure's compressive and bending resistance in the straight edge direction of the curved panels. 2. The curved panels mainly bear out-of-plane loads and heat dissipation functions, while each straight beam mainly bears axial loads; the functions of the two are decoupled, facilitating independent optimization. 3. Straight beams (including vertical straight beams and reinforced straight beams) together with curved beams and diagonal beams form a redundant force transmission network to prevent local buckling at the edges of curved panels.

[0033] The three-dimensional curved beam-plate unit cell structure provided by this invention has three symmetry planes, which pass through the center point of the unit cell and are parallel to the xy plane, yz plane, and xz plane, respectively. The x-direction is the direction of the arc chord length of the upper and lower curved panel cross-sections, the y-direction is the direction connecting the centers of the upper and lower curved panels, and the z-direction is the direction of the straight edges of the upper and lower curved panels.

[0034] The above is a structural division of the unit cell from a functional hierarchy perspective. From a geometric perspective, the unit cell 1 is composed of curved shell plate units and spatial beam frame units. The curved shell plate units include symmetrically arranged upper curved panel 111 and lower curved panel 112; the spatial beam frame units include 4 curved beams 113, 4 reinforcing straight beams 114 along the z-direction, 8 diagonal beams 121, and 1 vertical straight beam 3 along the y-direction, for a total of 17 beams.

[0035] The unit cell structure described in this invention successfully integrates "curved surfaces, plates, curved beams, and straight beams," surpassing traditional lattices and achieving a unity of "macroscopic curved surface shape" and "microscopic hybrid force transmission." When arranged in a lattice structure, it can give rise to the following emerging applications: (1) Next-generation conformal multifunctional carrier.

[0036] Intelligent car radar dome / antenna dome: The curved shape perfectly fits the car body, and the internal BCC / FCC dot matrix can be designed as a transparent frequency-selective structure, which ensures signal transmission while also having load-bearing, heat dissipation and lightweight functions.

[0037] Bionic robot shell and skeleton: The curved shape adapts to biological form, and the internal mixed lattice provides a lightweight and high-strength motion skeleton, which can be embedded with hydraulic or cooling systems through flow channels.

[0038] (2) Ultra-efficient energy management platform.

[0039] Phase change energy storage structure: Phase change material is injected into the lattice pores to achieve rapid heat storage / release using its huge specific surface area. It can be used in satellite thermal control systems (to cope with extreme temperature differences) and building energy-saving walls to achieve the integration of "structure-energy storage".

[0040] Catalytic reactor support: Its high specific surface area and controllable flow channels make it an ideal catalyst support for micro-chemical reactors or automotive exhaust catalytic converters, achieving dual enhancement of reaction and mass transfer.

[0041] (3) Customized biomechanical scaffolds.

[0042] Gradient biomimetic skeleton: By mixing SC / BCC / FCC arrangements, gradient changes in porosity and modulus can be achieved in different areas of the implant, accurately simulating the mechanical distribution of natural bone, greatly improving osseointegration effect and long-term stability.

[0043] This invention also discloses a three-dimensional curved beam-plate hybrid lattice structure, such as... Figure 5 and Figure 6The image shows a first preferred embodiment of the lattice structure. This embodiment provides a three-dimensional curved beam-slab-SC hybrid lattice structure, which is a flat plate structure formed by arranging a single unit cell 1 of the three-dimensional curved beam-slab in the XY plane, YZ plane, and XZ plane of a three-dimensional rectangular coordinate system (i.e., XY plane flat plate structure, YZ plane flat plate structure, and XZ plane flat plate structure). The flat plate structures of each plane intersect each other, and the intersections share a unit cell, ultimately resulting in a three-dimensional curved beam-slab-SC hybrid lattice structure composed of three mutually perpendicular flat plate lattice components. This three-dimensional curved beam-slab-SC hybrid lattice structure can be used as a multi-directional load-bearing corner reinforcement, applied to scenarios such as spacecraft cabin corners, automobile A-pillars, and aircraft fuselage-wing connection corner areas. The three flat plate structures can be independently extended along their respective plane directions. By adjusting the number of arrays in each direction, the structural size can be adapted to corner areas of different specifications. Multiple of these three-dimensional curved beam-slab-SC hybrid lattice structures can also be combined and spliced ​​to form a larger spatial frame.

[0044] like Figure 7 and Figure 8 The diagram shows a second preferred embodiment of the lattice structure. This embodiment provides a three-dimensional curved beam-plate-BCC hybrid lattice structure, which is generally a cuboid structure (this embodiment uses a cube structure as an example). Specifically: a unit cell 1 of the three-dimensional curved beam-plate is placed at one vertex of the cuboid and arrayed along one side of the cuboid to the other vertex of that side; then the unit cells of the previous vertex are arrayed along the two face diagonals and one body diagonal connected to that side, until the center of each diagonal; then the unit cells of the other vertex are also arrayed along the two face diagonals and one body diagonal connected to that side, until the center of each diagonal; finally, the unit cells on the body diagonals are filled to the two adjacent face diagonals, and the filling process does not change the orientation of the unit cells, finally obtaining structure A; each side of the cuboid structure obtains a structure A through the above spatial lattice method, finally forming a three-dimensional curved beam-plate-BCC hybrid lattice structure, and if the unit cells of adjacent structures A overlap, they share a single unit cell. It should be noted that for a cubic structure, each structure A is identical, differing only in orientation. However, for a cuboid structure, structure A varies due to differences in side length. This three-dimensional curved beam-slab-BCC hybrid lattice structure can serve as an independent load-bearing component or the core layer of a main load-bearing structure, applicable to scenarios with stringent requirements for lightweighting and multi-directional load-bearing capacity, such as spacecraft modules, aircraft bulkheads, and deep-sea pressure hulls. By adjusting the number of array iterations in the X, Y, and Z directions (i.e., the length, width, and height of the cuboid), the structural dimensions can be adapted to different load-bearing areas. By setting differentiated unit cell parameters (such as the curvature of the curved panel and the cross-section of the beam) in different areas, gradient design of structural performance can be achieved. Multiple of the aforementioned three-dimensional curved beam-slab-BCC hybrid lattice structures can be spliced ​​together in any direction to form larger spatial structures.

[0045] like Figure 9 and Figure 10 The image shows a third preferred embodiment of the lattice structure. This embodiment provides a three-dimensional curved beam-plate-FCC hybrid lattice structure, specifically: a unit cell 1 of the three-dimensional curved beam-plate is placed at the vertex of a cube, with one side of the cube connected to the vertex oriented in the Z direction of the Cartesian coordinate system, and the other two sides oriented in the X and Y directions, respectively; the unit cell at the vertex is arrayed M times along the body diagonal and the mirror body diagonal connected to the vertex, forming a total of M rows, where the mirror body diagonal is obtained by mirroring the body diagonal with the YZ plane; then the first row of unit cells along the body diagonal... The unit cells in the i-th row (i=1,2,...,M) are arrayed N times along the Z-direction. The unit cells in the i-th row are arrayed N-2i-2 times along the Z-direction (N≥2M), and the unit cells in the M-th row are arrayed twice along the Z-direction, thus forming two symmetrical panels. Then, the aforementioned unit cells are added in the X-direction between the two panels to form structure H. Each edge of the top and bottom faces of the cube is used to obtain a structure H through the above spatial lattice method, resulting in a total of 8 structures H. Finally, a three-dimensional curved beam-plate-FCC hybrid lattice structure is obtained, where adjacent structure H units share a unit cell if they overlap. This three-dimensional curved beam-plate-BCC hybrid lattice structure can be used as an independent load-bearing component or a core layer of a main load-bearing structure, applicable to scenarios with strict requirements for lightweighting and multi-directional load-bearing, such as spacecraft modules, aircraft frames, and deep-sea pressure hulls. By adjusting the number of arrays in the X, Y, and Z directions, the structural dimensions can be adapted to different load-bearing areas. By setting differentiated unit cell parameters (such as panel curvature and beam cross-section) in different areas, gradient design of structural performance can be achieved. Multiple of the aforementioned three-dimensional curved beam-plate-BCC hybrid lattice structures can be spliced ​​together in any direction to form a larger spatial structure.

[0046] It should be noted that the above three lattice structures can also be spliced ​​or superimposed on each other, and the orientation of each unit cell in each lattice structure can be the same or different. In each of the three lattice structures (the three planar structures in the first embodiment, structure A in the second embodiment, and structure H in the third embodiment), the orientation of each unit cell is the same, and the orientation of unit cells in different structures is also the same. However, when other structures are obtained by rotating and replicating the basic structure, the orientation of unit cells within each structure is the same, while the orientation of unit cells in different structures will be different. The performance advantages of this arrangement are: 1. Balanced multi-directional load-bearing capacity: In mutually perpendicular flat plates, the curved panels are perpendicular to their respective flat surfaces. When the structure is subjected to loads from different directions, each direction has curved panels providing efficient bending stiffness, avoiding the emergence of "weak directions." 2. Applicable to "conformal" designs: For applications requiring conformal shapes or angular outlines (such as spacecraft cabin corners, car A-pillars, etc.), the rotational replication method can better adapt to non-planar shapes, achieving structural and shape unity. 3. To avoid the weakness of "directionality," if all unit cells are oriented in the same direction, the load-bearing advantage of the curved panel cannot be utilized when the load direction is perpendicular to the normal direction of the curved panel, and the structure may experience premature instability. The rotational replication method ensures that each flat plate has a curved panel participating in the load-bearing when subjected to out-of-plane loads.

[0047] The above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the technical scope of the present invention. Therefore, any changes or modifications made in accordance with the claims and specification of the present invention should fall within the scope of the patent of the present invention.

Claims

1. A three-dimensional curved beam-plate unit cell, characterized in that: The unit cell (1) includes an outer frame (11) and a BCC skeleton (12). The BCC skeleton is located inside the unit cell and is connected to the outer frame through nodes. The outer frame (11) includes an upper curved panel (111) and a lower curved panel (112) arranged symmetrically. A concave curved beam (113) is provided between the four corners of the upper and lower curved panels, so that the outer frame forms a concave structure. The BCC skeleton (12) is composed of 8 oblique beams (121). The inner ends of the 8 oblique beams are connected to each other and located at the center point of the unit cell. The outer ends of the oblique beams are respectively connected to the four corners of the upper and lower curved panels.

2. The three-dimensional curved beam-plate unit cell according to claim 1, characterized in that: A vertical straight beam (3) is further provided, which passes through the center point of the unit cell (1) and connects the upper and lower curved panels (111, 112).

3. A three-dimensional curved beam-plate unit cell according to claim 1 or 2, characterized in that: The outer ends of the eight diagonal beams (121) of the BCC frame (12) are also connected to four reinforcing straight beams (114), which are respectively parallel to or connected to the straight edges on both sides of the upper and lower curved panels (111, 112).

4. A three-dimensional curved beam-plate unit cell according to claim 1 or 2, characterized in that: The arc of the curved beam (113) is a sine curve.

5. A three-dimensional curved beam-plate unit cell according to claim 1 or 2, characterized in that: The surface curves of the upper and lower curved panels (111, 112) are circular arcs, parabolas, spline curves or other function curves.

6. A three-dimensional curved beam-plate unit cell hybrid lattice structure, characterized in that: The lattice structure is formed by the periodic arrangement of the unit cells (1) as described in any one of claims 1-5.

7. A three-dimensional curved beam-plate unit cell hybrid lattice structure according to claim 6, characterized in that: The lattice structure is a three-dimensional curved beam-slab-SC hybrid lattice structure, which is a flat plate structure formed by an array of a three-dimensional curved beam-slab unit cell (1) on the XY plane, YZ plane and XZ plane of the three-dimensional rectangular coordinate system, and the flat plate structures of each plane intersect each other, and the unit cell is shared at the intersection, and finally a three-dimensional curved beam-slab-SC hybrid lattice structure composed of three mutually perpendicular flat plate lattice components is obtained.

8. A three-dimensional curved beam-plate unit cell hybrid lattice structure according to claim 6, characterized in that: The lattice structure is a three-dimensional curved beam-plate-BCC hybrid lattice structure, which is a cuboid structure in general. Specifically, a three-dimensional curved beam-plate unit cell (1) is placed at one vertex of the cuboid and arrayed along one side of the cuboid to the other vertex of the side. Then, the unit cells of the previous vertex are arrayed along the two face diagonals and one body diagonal connected to the side until the center of each diagonal. Then, the unit cells of the other vertex are also arrayed along the two face diagonals and one body diagonal connected to the side until the center of each diagonal. Finally, the unit cells on the body diagonal are filled to the two adjacent face diagonals. The filling process does not change the direction of the unit cells, and finally, structure A is obtained. Each side of the cuboid structure obtains a structure A through the above spatial lattice method, and finally constitutes a three-dimensional curved beam-plate-BCC hybrid lattice structure. If the unit cells of adjacent structures A overlap, they share a unit cell.

9. A three-dimensional curved beam-plate unit cell hybrid lattice structure according to claim 6, characterized in that: The lattice structure is a three-dimensional curved beam-plate-FCC hybrid lattice structure, specifically: a three-dimensional curved beam-plate unit cell (1) is placed at the vertex of a cube, and the direction of one side of the cube connected to the vertex is the Z direction of the rectangular coordinate system, and the directions of the other two sides are the X direction and the Y direction, respectively; the unit cell of the vertex is arrayed M times along the body diagonal and the mirror body diagonal direction connected to the vertex, for a total of M rows, and the mirror body diagonal is obtained by mirroring the body diagonal with the YZ plane; then the first row of the body diagonal unit cell is arrayed. The cells are arrayed N times along the Z direction. The cells in the i-th row are arrayed N-2i-2 times along the Z direction, where i = 1, 2, ..., M, N ≥ 2M. The cells in the M-th row are arrayed 2 times along the Z direction, thus forming two symmetrical panels. Then, the cells are added in the X direction between the two panels to form structure H. Each edge of the upper and lower faces of the cube is obtained through the above spatial lattice method to form a structure H, for a total of 8 structures H, finally resulting in a three-dimensional curved beam-plate-FCC hybrid lattice structure. If the cells of adjacent structures H overlap, they share a cell.

10. A three-dimensional curved beam-plate unit cell hybrid lattice structure according to any one of claims 7-9, characterized in that: In the lattice structure, the orientation of each unit cell within each structure is the same, while the orientation of unit cells between different structures is different.

Images