Single cell body and lattice metamaterial structure

Abstract

The embodiment of the invention provides a unit cell body and a lattice metamaterial structure. Each unit cell body comprises an outer frame, the outer frame is of a cubic structure and comprises three sets of opposite surfaces, each surface is provided with two sets of opposite side edges, the two surfaces belonging to the same set are provided with connecting convex beams extending along the side edges, and the connecting convex beams extend along the side edges of the two surfaces belonging to the same set. A group of corresponding side edges of one surface of the connecting convex beam are provided with connecting grooves extending along the side edges, the cross section of each connecting groove is non-circular and is in a continuous arc shape, the connecting convex beam is provided with an embedded part, and the embedded part is matched with the cross section of each connecting groove in shape; the supporting assembly is arranged in the space defined by the outer frame and used for supporting the outer frame. According to the unit cell body provided by the invention, high-precision rapid assembly and multi-directional mechanical property reinforcement of the lattice metamaterial structure are realized through the convex-concave matching design of the elliptical geometric configuration and in combination with a directional interlocking mechanism of the modular unit cells.

Description

Technical Field

[0001] This application relates to the field of lattice metamaterials technology, and more particularly to a unit cell and lattice metamaterial structure. Background Technology

[0002] With the deepening of human space exploration and space utilization activities, the on-orbit construction and maintenance of large-scale space structures, such as space solar power stations and large space telescopes, has become an inevitable trend in the future development of space technology. Meanwhile, in the field of ground applications, lattice metamaterials, due to their lightweight characteristics, high specific strength / stiffness, and potential for multifunctional integrated design, show broad prospects in aerospace, advanced equipment, and advanced transportation vehicles.

[0003] However, existing technologies face significant challenges in the macroscopic fabrication of large-scale or complex geometrically shaped lattice metamaterial structures. On the one hand, while additive manufacturing can directly form complex microstructures, it suffers from low efficiency, high cost, limited material selection, and potential precision issues when manufacturing large-scale components. On the other hand, although modular assembly strategies can circumvent size limitations and achieve regional customization, traditional unit cell splicing methods, such as bolted connections, adhesive bonding, or simple mortise and tenon joints, often fail to simultaneously meet the requirements for high-precision positioning, rapid and efficient assembly, and robust and reliable mechanical interlocking. In particular, the existing mechanical interlocking designs of rectangular or circular concave-convex structures are insufficient to meet practical needs, limiting the application scenarios of lattice metamaterial structures. Summary of the Invention

[0004] This application provides a unit cell and a lattice metamaterial, which achieves high-precision rapid assembly and multi-directional mechanical property enhancement of the lattice metamaterial structure through the convex-concave fit design of the elliptical geometry and the directional interlocking mechanism of the modular unit cell.

[0005] In a first aspect, this application provides a unit cell for assembling lattice metamaterial structures, comprising: an outer frame, the outer frame being a cubic structure, the outer frame including three sets of opposing surfaces, each of the surfaces having two sets of opposing sides, wherein one set of sides of one of the surfaces belonging to the same set has a connecting beam extending along the side, and the corresponding set of sides of the other surface has a connecting groove extending along the side, wherein the cross-section of the connecting groove is non-circular and is a continuous arc, the connecting beam having an embedding portion, the embedding portion being adapted to the cross-sectional shape of the connecting groove; and a support assembly disposed within the space enclosed by the outer frame and used to support the outer frame.

[0006] The unit cells provided in this application can be fitted and matched with the connecting grooves through the embedded parts of the connecting beams, enabling self-guided precise positioning and rapid and efficient assembly between unit cells. Simultaneously, a strong and reliable mechanical interlock can be formed, effectively resisting multiple loads and improving the overall mechanical stability. Furthermore, unit cells can be used to assemble lattice metamaterial structures, making them scalable and solving the problems of macroscopic manufacturing of large-size or complex geometrically structured lattice metamaterials in existing technologies, simplifying the manufacturing process and reducing manufacturing costs.

[0007] In some embodiments, both the connecting groove and the embedding portion have elliptical cross-sections.

[0008] In some embodiments, the connecting beam further includes a base portion for connecting with the outer frame, wherein the outer peripheral wall of the base portion is connected to and smoothly transitions with the outer peripheral wall of the embedded portion.

[0009] In some embodiments, the ellipse has a major axis and a minor axis, and the ratio of the length of the major axis to the length of the minor axis is 1.5-3.

[0010] In some embodiments, the outer frame includes a front surface and a rear surface that are opposite each other in the front-back direction, a left surface and a right surface that are opposite each other in the left-right direction, and an upper surface and a lower surface that are opposite each other in the up-down direction; the left side and the right side of the front surface are respectively provided with connecting beams extending in the up-down direction.

[0011] The front and rear sides of the right surface are respectively provided with connecting grooves extending in the vertical direction; the front and rear sides of the upper surface are respectively provided with connecting protruding beams extending in the horizontal direction.

[0012] In some embodiments, the outer frame includes a front surface and a rear surface that are opposite each other in the front-back direction, a left surface and a right surface that are opposite each other in the left-right direction, and an upper surface and a lower surface that are opposite each other in the up-down direction; the left side and the right side of the front surface are respectively provided with connecting beams extending in the up-down direction.

[0013] The front and rear sides of the right surface are respectively provided with connecting grooves extending in the vertical direction; the left and right sides of the upper surface are respectively provided with connecting protruding beams extending in the front-back direction.

[0014] In some embodiments, the outer frame includes a front surface and a rear surface opposite to each other in the front-rear direction, a left surface and a right surface opposite to each other in the left-right direction, and an upper surface and a lower surface opposite to each other in the up-down direction; the left side and the right side of the front surface are respectively provided with connecting protrusions extending in the up-down direction; the upper side and the lower side of the right surface are respectively provided with connecting grooves extending in the front-rear direction; the front side and the rear side of the upper surface are respectively provided with connecting protrusions extending in the left-right direction.

[0015] In some embodiments, the support component includes a plurality of support columns corresponding to the corners of the outer frame, the plurality of support columns extending from the corresponding corners toward the geometric center of the outer frame and connecting thereto.

[0016] Secondly, this application provides a lattice metamaterial structure, comprising: any one of the unit cells described in the previous application, wherein there are multiple unit cells, and the opposite surfaces of two adjacent unit cells are connected by the connecting beam embedded in the connecting groove.

[0017] In some embodiments, the lattice metamaterial structure includes at least two of a first type of unit cell, a second type of unit cell, and a third type of unit cell; wherein, the first type of unit cell has connecting beams extending in the vertical direction on the left and right sides of its front surface, connecting grooves extending in the vertical direction on the front and rear sides of its right surface, and connecting beams extending in the horizontal direction on the front and rear sides of its upper surface; the second type of unit cell has connecting beams extending in the vertical direction on the left and right sides of its front surface, connecting grooves extending in the vertical direction on the front and rear sides of its right surface, and connecting beams extending in the front-back direction on the left and right sides of its upper surface.

[0018] The lattice metamaterial structure provided in this application can be assembled into a monolithic lattice metamaterial structure through the lattice assembly of unit cells. This solves the macroscopic manufacturing problem of large-size or complex geometric lattice metamaterial structures, simplifies the manufacturing process, makes it scalable, and reduces manufacturing costs. Attached Figure Description

[0019] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0020] Figure 1 A schematic diagram of the structure of the unit cell provided in this application, excluding the connecting beams and connecting grooves;

[0021] Figure 2 This is a front view of the elliptical connecting beam provided in this application.

[0022] Figure 3 A front view schematic diagram of the radial structure of the elliptical connecting beam provided in this application;

[0023] Figure 4 This is a structural schematic diagram of the first type of unit cell provided in this application;

[0024] Figure 5 This is a structural schematic diagram of the second type of unit cell provided in this application;

[0025] Figure 6 This is a structural schematic diagram of the third type of unit cell provided in this application;

[0026] Figure 7 The assembly flowchart and structural diagram of the first assembly provided in this application;

[0027] Figure 8 The assembly flowchart and structural diagram of the second assembly provided in this application;

[0028] Figure 9 The assembly flowchart and structural diagram of the third assembly provided in this application;

[0029] Figure 10 The assembly flowchart and structural diagram of the fourth assembly provided in this application;

[0030] Figure 11 The assembly flowchart and structural diagram of the fifth assembly provided in this application;

[0031] Figure 12 The assembly flowchart and structural diagram of the sixth assembly provided in this application;

[0032] Figure 13 A structural schematic diagram of the seventh assembly provided in this application;

[0033] Figure 14 The assembly flowchart and structural diagram of the eighth assembly provided in this application.

[0034] Explanation of reference numerals in the attached figures:

[0035] 100-unit cells;

[0036] 110 - Type I unit cell; 120 - Type II unit cell; 130 - Type III unit cell; 140 - Unit cell without connecting beams and connecting grooves; 150 - New type of unit cell;

[0037] 1-Outer frame; 10-Connecting beam; 11-Connecting groove;

[0038] 101-Embedded part; 102-Base part; 101a-Major axis; 101b-Minor axis;

[0039] 103 - Vertical protruding beam; 104 - Horizontal protruding beam; 111 - Vertical groove; 112 - Horizontal groove;

[0040] 2-Supporting component; 20-Supporting column; 21-Geometric center of outer frame;

[0041] 200-lattice metamaterial structure;

[0042] 210 - First assembly; 220 - Second assembly; 230 - Third assembly; 240 - Fourth assembly; 250 - Fifth assembly; 260 - Sixth assembly; 270 - Seventh assembly; 280 - Eighth assembly.

[0043] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0044] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0045] In the field of advanced materials structure and manufacturing technology, lattice metamaterial structures have shown great promise in cutting-edge applications such as lightweight load-bearing structures for aerospace, personalized implants for biomedicine, and flexible electronic device substrates due to their outstanding lightweight potential, designable mechanical properties, and multifunctionality.

[0046] However, existing technologies face significant challenges in the macroscopic fabrication of large-scale or complex geometrically shaped lattice metamaterial structures. On the one hand, while additive manufacturing can directly form complex microstructures, it suffers from low efficiency, high cost, limited material selection, and potential precision issues when manufacturing large-scale components. On the other hand, although modular assembly strategies can circumvent size limitations and achieve regional customization, traditional unit cell splicing methods, such as bolted connections, adhesive bonding, or simple mortise and tenon joints, often fail to simultaneously meet the requirements for high-precision positioning, rapid and efficient assembly, and robust and reliable mechanical interlocking. In particular, the existing mechanical interlocking designs of rectangular or circular concave-convex structures are insufficient to meet practical needs, limiting the application scenarios of lattice metamaterial structures.

[0047] In view of this, this application provides a unit cell and lattice metamaterial structure. On the one hand, by adapting and engaging the embedded part of the connecting beam with the connecting groove, self-guided precise positioning and rapid and efficient assembly between unit cells can be achieved. At the same time, a strong and reliable mechanical interlock can be formed, effectively resisting multiple loads and improving the stability of the overall mechanical properties. On the other hand, a monolithic lattice metamaterial structure can be spliced ​​together by assembling the unit cells into a lattice, solving the macroscopic manufacturing problem of large-size or complex geometric lattice metamaterial structures, making them scalable and reducing manufacturing costs.

[0048] Firstly, this application provides a unit cell 100 for assembling a lattice metamaterial structure 200. The lattice metamaterial structure 200 is a two-dimensional or three-dimensional artificial structure formed by a precisely designed periodic arrangement, possessing unique physical properties that cannot be achieved using natural materials. Its core features include periodic arrangement, geometric parameter control, and multifunctional integration capabilities.

[0049] Combination Figure 1 The unit cell 100 provided in this application is a unit cell 100 containing connecting beams 10 and connecting grooves 11, which is a modification and upgrade of the existing unit cell 140 that does not contain connecting beams and connecting grooves.

[0050] Combination Figure 4 , Figure 5 and Figure 6 The unit cell 100 includes an outer frame 1 and a support assembly 2. The outer frame 1 has a cubic structure and includes three sets of opposing surfaces. Each surface has two sets of opposing sides. For two surfaces belonging to the same set, one set of sides on one surface has a connecting protrusion 10 extending along the side, and the corresponding set of sides on the other surface has a connecting groove 11 extending along the side. The cubic structure is a body-centered cubic structure of a BBC-type unit cell.

[0051] This can be understood as follows: the outer frame 1 includes three sets of opposing surfaces, i.e., six surfaces; each surface has two sets of opposing sides, i.e., four sides. Two surfaces belonging to the same set have a set of connecting beams 10 on one surface and a set of connecting grooves 11 on the other surface. The connecting beams 10 or the connecting grooves 11 are located on both sides of one surface, and the connecting beams 10 or the connecting grooves 11 extend along the sides.

[0052] Combination Figure 2 and Figure 3 The connecting groove 11 has a non-circular, continuous arc cross-section, and the connecting beam 10 has an insert portion 101 that matches the cross-sectional shape of the connecting groove 11. Specifically, the insert portion 101's structural shape is identical to the cross-sectional shape of the connecting groove 11. Because the insert portion 101 of the connecting beam 10 fits into the cross-sectional shape of the connecting groove 11, self-guiding precise positioning and rapid, efficient assembly are achieved.

[0053] Alternatively, a variable-angle rotation interface can be introduced into the design of the connecting beam 10 and the connecting groove 11 of the unit cell 100. This allows the alignment of the connecting beam 10 and the connecting groove 11 to be adjusted by rotating the unit cell 100 during assembly, thereby adapting to non-orthogonal geometric requirements. For example, the connecting beam 10 of the unit cell 100 can be designed as a structure that can be rotatably embedded in the connecting groove. By rotating the beam by angles such as 0°, 45°, or 90°, the extension direction of the beam can be changed to match assembly requirements in different orientations.

[0054] Specifically, a rotation limiting groove is designed at the end of the connecting beam 10 of the unit cell 100, and a rotation limiting protrusion is designed in the connecting groove 11. The rotation limiting groove and the rotation limiting protrusion can cooperate, and the contact direction between the connecting beam 10 and the connecting groove 11 can be adjusted by rotating the angle to achieve flexible assembly of non-orthogonal geometric configuration.

[0055] In this way, on the one hand, it breaks through the limitation of traditional modular assembly that only supports orthogonal directions, enabling rapid assembly of the unit cell 100 in complex geometric configurations; on the other hand, it ensures that the connecting beam 10 and the connecting groove 11 form a stable interlock, avoiding connection failure due to angular deviation. In addition, it significantly improves the degree of freedom in structural design, making it suitable for asymmetric structural scenarios, such as biomimetic robotic arms and irregular lattice metamaterials.

[0056] Optionally, the connecting beam 10 and connecting groove 11 of the unit cell 100 can be designed as a split-nested structure, that is, the connecting beam 10 is composed of multiple sub-connecting beams, and the connecting groove 11 is composed of multiple sub-connecting grooves, achieving more complex constraint patterns through split-nesting. Specifically, a split-nesting interface is introduced into the connecting beam 10 and connecting groove 11 of the unit cell 100. The connecting beam 10 is composed of two sub-connecting beams that can be slidably embedded into the connecting groove 11, achieving multi-directional constraints through sliding engagement. The connecting groove 11 contains a composite structure of multiple sub-connecting grooves, with each sub-connecting groove corresponding to one sub-connecting beam, achieving multi-directional constraints through split-nesting. An elastic locking element, such as a miniature spring, is designed at the split-nesting interface to ensure that the sub-connecting beams automatically lock after being embedded.

[0057] Thus, multi-degree-of-freedom constraints and dynamic locking are achieved through a split-nested design. On the one hand, the split-nested interface allows individual cells to lock gradually during assembly, reducing the difficulty of one-time fitting and improving assembly efficiency. On the other hand, the elastic locking components ensure a stable connection after the sub-connecting beams are embedded, preventing loosening due to vibration or dynamic loads. In addition, the multi-directional constraint capability significantly enhances the overall stiffness of the structure, while supporting partial disassembly and maintenance, such as replacing only the damaged sub-beams.

[0058] The support component 2 is located within the space enclosed by the outer frame 1 and is used to support the outer frame 1. Due to the support component 2 supporting the outer frame 1, the structure of the unit cell 100 has good mechanical properties.

[0059] This application provides a unit cell 100 that addresses the shortcomings of existing mechanical interlock designs. By adapting and fitting the insert 101 of the connecting beam 10 with the connecting groove 11, self-guiding precise positioning and rapid, efficient assembly of the unit cells 100 can be achieved. Simultaneously, a strong and reliable mechanical interlock can be formed, effectively resisting multiple loads and improving the overall mechanical stability, thus expanding the application scenarios of lattice metamaterials. Furthermore, the unit cell 100 can be used to assemble lattice metamaterial structures, making them scalable and solving the problems of macroscopic manufacturing of large-size or complex geometrically structured lattice metamaterials in existing technologies, simplifying the manufacturing process and reducing manufacturing costs.

[0060] Combination Figure 2 and Figure 3 In some embodiments, both the connecting groove 11 and the insert 101 have elliptical cross-sections. The interlocking relationship formed by the contact of the elliptical surfaces of the connecting groove 11 and the insert 101 serves as a multi-directional constraint. The elliptical structural design of the cross-sections of the connecting groove 11 and the insert 101 is inspired by the hard shell of a beetle; this biomimetic elliptical structural design gives the connection between the connecting groove 11 and the insert 101 excellent tensile strength. Furthermore, compared to traditional rectangular or circular concave-convex structures, it offers advantages in resisting multi-directional loads, ensuring self-guiding assembly processes, and providing stable and controllable interfacial mechanical properties.

[0061] Thus, through the convex-concave fit design of the elliptical connecting beam 10 and the connecting groove 11, combined with the directional interlocking mechanism of the modular unit cell 100, the high-precision rapid assembly and multi-directional mechanical property enhancement of the lattice metamaterial structure 200 are achieved.

[0062] Combination Figure 3 In some embodiments, the connecting beam 10 further includes a base portion 102, which is used to connect with the outer frame 1. The outer peripheral wall of the base portion 102 is connected to the outer peripheral wall of the embedded portion 101 and smoothly transitions. It can be understood that the connecting beam 10 has a base portion 102 and an embedded portion 101, and the base portion 102 and the embedded portion 101 are an integral whole.

[0063] The outer peripheral wall of the base portion 102 is connected to the outer peripheral wall of the embedded portion 101 with a smooth transition, which means that there are no sharp turns at the connection between the outer peripheral wall of the base portion 102 and the outer peripheral wall of the embedded portion 101, thereby reducing stress concentration and improving fatigue strength and processing feasibility.

[0064] Therefore, this design can improve the connection strength between the outer frame 1, the base part 102 and the embedded part 101, and ensure the interface strength and stability under multi-directional loads.

[0065] Combination Figure 3 In some embodiments, the ellipse has a major axis 101a and a minor axis 101b, and the ratio of the length of the major axis 101a to the length of the minor axis 101b is 1.5-3. For example, the ratio of the length of the major axis 101a to the length of the minor axis 101b can be 1.5, 1.8, 2, 2.2, 2.4, 2.6, 2.8 and 3. Of course, this application is not limited to this.

[0066] Thus, the design of the ratio of the length of the major axis 101a to the length of the minor axis 101b is used to achieve self-guided fitting, reduce positioning errors, significantly reduce the difficulty of manual alignment, and improve assembly efficiency; at the same time, the close contact of the elliptical surfaces enhances the multi-directional constraint capability, enabling the structure to maintain stable performance under complex loads.

[0067] Alternatively, in the design of the connecting beam 10 and connecting groove 11 of the unit cell 100, gradient parameter adjustment can be introduced. By simulating the stress distribution in different regions through finite element analysis and considering the influence of elliptical geometric parameters on the contact area and constraint direction, a gradient configuration of the connecting beam 10 and connecting groove 11 can be designed. That is, based on differences in assembly direction or mechanical requirements, the ratio of the length of the major axis 101a to the length of the minor axis 101b of the ellipse can be locally optimized. For example, an elliptical beam with a major axis to minor axis ratio of 3:1 can be used on the transverse connecting surface to ensure strong constraint during transverse fitting; while an elliptical beam with a ratio of 1.5:1 can be used on the vertical connecting surface to allow slight deformation to adapt to dynamic loads.

[0068] Thus, by adjusting local geometric parameters in a gradient manner, regional customization of mechanical properties is achieved. On the one hand, it can significantly enhance the interfacial shear strength at transverse connection surfaces, avoiding slip failure caused by dynamic loads; on the other hand, it can retain a certain deformation adaptability at vertical connection surfaces, improving the stability of the structure in dynamic environments. In addition, the gradient design is compatible with multi-material integration, such as using rigid materials in high-stress areas and flexible materials in low-stress areas, further expanding the application range.

[0069] Combination Figure 4 In some embodiments, the outer frame 1 includes a front surface and a rear surface that are opposite each other in the front-back direction, a left surface and a right surface that are opposite each other in the left-right direction, and an upper surface and a lower surface that are opposite each other in the up-down direction; the left side and the right side of the front surface are respectively provided with connecting protrusions 10 extending in the up-down direction; the front side and the rear side of the right surface are respectively provided with connecting grooves 11 extending in the up-down direction; the front side and the rear side of the upper surface are respectively provided with connecting protrusions 10 extending in the left-right direction.

[0070] Among them, there must be a connecting beam 10 and a connecting groove 11 on the two corresponding surfaces in the front-back direction, left-right direction and up-down direction, and the extending directions of the connecting beam 10 and the connecting groove 11 are consistent.

[0071] The characterization of this unit cell type 100 is defined as follows, wherein vertical convex beam 103 and horizontal convex beam 104 are both connecting convex beams 10, and vertical groove 111 and horizontal groove 112 are both connecting grooves.

[0072] Specifically, the front surface is the first surface and has a vertical protrusion beam 103; the right surface is the second surface and has a vertical groove 111; the upper surface is the third surface and has a horizontal protrusion beam 104; the rear surface is the fourth surface and has a vertical groove 111; the left surface is the fifth surface and has a vertical protrusion beam 103; and the lower surface is the sixth surface and has a horizontal groove 112.

[0073] Thus, one type of unit cell 100 is provided, which can be quickly assembled through an elliptical protruding beam and an elliptical groove structure, and has precise self-guiding positioning, thereby improving the reliability of mechanical interlocking.

[0074] Combination Figure 5 In some embodiments, the outer frame 1 includes a front surface and a rear surface that are opposite each other in the front-back direction, a left surface and a right surface that are opposite each other in the left-right direction, and an upper surface and a lower surface that are opposite each other in the up-down direction; the left side and the right side of the front surface are respectively provided with connecting protrusions 10 extending in the up-down direction; the front side and the rear side of the right surface are respectively provided with connecting grooves 11 extending in the up-down direction; the left side and the right side of the upper surface are respectively provided with connecting protrusions 10 extending in the front-back direction.

[0075] Among them, there must be a connecting beam 10 and a connecting groove 11 on the two corresponding surfaces in the front-back direction, left-right direction and up-down direction, and the extending directions of the connecting beam 10 and the connecting groove 11 are consistent.

[0076] The characterization of this unit cell type 100 is defined as follows, wherein vertical convex beam 103 and horizontal convex beam 104 are both connecting convex beams 10, and vertical groove 111 and horizontal groove 112 are both connecting grooves.

[0077] Specifically, the front surface is the seventh surface and has a vertical protrusion beam 103; the right surface is the eighth surface and has a vertical groove 111; the upper surface is the ninth surface and has a vertical protrusion beam 103; the rear surface is the tenth surface and has a vertical groove 111; the left surface is the eleventh surface and has a vertical protrusion beam 103; and the lower surface is the twelfth surface and has a vertical groove 111.

[0078] Thus, a second type of unit cell 100 is provided, which can be quickly assembled through an elliptical protruding beam and an elliptical groove structure, and has precise self-guiding positioning, thereby improving the reliability of mechanical interlocking.

[0079] Combination Figure 6 In some embodiments, the outer frame 1 includes a front surface and a rear surface that are opposite each other in the front-back direction, a left surface and a right surface that are opposite each other in the left-right direction, and an upper surface and a lower surface that are opposite each other in the up-down direction; the left side and the right side of the front surface are respectively provided with connecting protrusions 10 extending in the up-down direction; the upper side and the lower side of the right surface are respectively provided with connecting grooves 11 extending in the front-back direction; the front side and the rear side of the upper surface are respectively provided with connecting protrusions 10 extending in the left-right direction.

[0080] Among them, there must be a connecting beam 10 and a connecting groove 11 on the two corresponding surfaces in the front-back direction, left-right direction and up-down direction, and the extending directions of the connecting beam 10 and the connecting groove 11 are consistent.

[0081] The characterization of the unit cell 100 is defined as follows, wherein the vertical convex beam 103 and the horizontal convex beam 104 are both connecting convex beams 10, and the vertical groove 111 and the horizontal groove 112 are both connecting grooves.

[0082] Specifically, the front surface is the thirteenth surface and has a vertical protrusion beam 103; the right surface is the fourteenth surface and has a horizontal groove 112; the upper surface is the fifteenth surface and has a horizontal protrusion beam 104; the rear surface is the sixteenth surface and has a vertical groove 111; the left surface is the seventeenth surface and has a horizontal protrusion beam 104; and the lower surface is the eighteenth surface and has a horizontal groove 112.

[0083] Thus, a third type of unit cell 100 is provided, which can be quickly assembled through an elliptical protruding beam and an elliptical groove structure, and has precise self-guiding positioning, thereby improving the reliability of mechanical interlocking.

[0084] Combination Figure 4 , Figure 5 and Figure 6 In some embodiments, the support component 2 includes a plurality of support columns 20 corresponding to the corners of the outer frame 1, and the plurality of support columns 20 extend from the corresponding corners toward the geometric center 21 of the outer frame and are connected.

[0085] This can be understood as eight supporting columns 20 extending from the eight corners of the outer frame 1 and towards the geometric center 21 of the outer frame 1, where they connect.

[0086] In this way, the loads acting on the surface, side or corner of the outer frame 1 will be transmitted to the corner of the outer frame 1, and then to the eight support columns 20; and the eight support columns 20 are symmetrically arranged and connected at the geometric center 21 of the outer frame, so that the loads transmitted to the eight support columns 20 will be canceled at the geometric center 21 of the outer frame.

[0087] Thus, the symmetrical arrangement of the support columns 20 provides better support for the outer frame 1, thereby enabling the unit cell 130 to better bear multi-directional loads and have good interface strength and stability.

[0088] Secondly, this application provides a lattice metamaterial structure 200, including any one of the unit cells 130, wherein there are multiple unit cells 100; the two opposite surfaces belonging to two adjacent unit cells 100 are connected by connecting beams 10 embedded in connecting grooves 11.

[0089] The lattice metamaterial provided in this application can form an expandable lattice metamaterial structure 200 by connecting multiple unit cells 100. On the one hand, it can solve the problems of macroscopic manufacturing of large-size or complex geometric lattice metamaterials in existing technologies; on the other hand, it can achieve rapid, precise, strong and reversible interlocking connections between unit cells 130, effectively solving core problems such as assembly efficiency, positioning accuracy and controllability of mechanical properties in the manufacturing of macroscopic lattice structures. In addition, it improves the reconfigurability and expandability of the lattice metamaterial structure 200, which can simplify the manufacturing process, reduce manufacturing costs, and improve reliability and maintainability.

[0090] Combination Figure 4 , Figure 5 and Figure 6 In some embodiments, the lattice metamaterial structure 200 includes at least one of a first type of unit cell 110, a second type of unit cell 120, and a third type of unit cell 130.

[0091] This can be understood as defining three types of unit cells 100, which correspond to the three types of unit cells 100 mentioned above, namely, the first type of unit cell 110, the second type of unit cell 120, and the third type of unit cell 130.

[0092] Specifically, the left and right sides of the front surface of the first type of unit cell 110 are respectively provided with connecting protrusions 10 extending in the vertical direction, the front and rear sides of the right surface are respectively provided with connecting grooves 11 extending in the vertical direction, and the front and rear sides of the upper surface are respectively provided with connecting protrusions 10 extending in the horizontal direction.

[0093] The second type of unit cell 120 has connecting protrusions 10 extending in the vertical direction on the left and right sides of the front surface, connecting grooves 11 extending in the vertical direction on the front and rear sides of the right surface, and connecting protrusions 10 extending in the front and rear directions on the left and right sides of the upper surface.

[0094] The third type of unit cell 130 has connecting protrusions 10 extending in the vertical direction on the left and right sides of the front surface, connecting grooves 11 extending in the front and back direction on the upper and lower sides of the right surface, and connecting protrusions 10 extending in the left and right direction on the front and rear sides of the upper surface.

[0095] The three types of characterization of unit cell 100 are defined as follows.

[0096] Specifically, the first type of unit cell 110 has the following characteristics: the front surface is the first surface with vertical convex beams 103; the right surface is the second surface with vertical grooves 111; the upper surface is the third surface with horizontal convex beams 104; the rear surface is the fourth surface with vertical grooves 111; the left surface is the fifth surface with vertical convex beams 103; and the lower surface is the sixth surface with horizontal grooves 112.

[0097] Type II unicellular 120: the front surface is the seventh surface with vertical convex beams 103; the right surface is the eighth surface with vertical grooves 111; the upper surface is the ninth surface with vertical convex beams 103; the rear surface is the tenth surface with vertical grooves 111; the left surface is the eleventh surface with vertical convex beams 103; and the lower surface is the twelfth surface with vertical grooves 111.

[0098] The third type of unit cell 130: the front surface is the thirteenth surface with vertical ridges 103; the right surface is the fourteenth surface with transverse grooves 112; the upper surface is the fifteenth surface with transverse ridges 104; the rear surface is the sixteenth surface with vertical grooves 111; the left surface is the seventeenth surface with transverse ridges 104; and the lower surface is the eighteenth surface with transverse grooves 112.

[0099] Thus, the first type of unit cell 110, the second type of unit cell 120 and the third type of unit cell 130 can be used to assemble a lattice, making it scalable and able to be assembled into a large-size or complex geometric lattice metamaterial.

[0100] There are multiple assembly methods for the lattice metamaterial structure 200, including single-layer and multi-layer lattice metamaterial structures. Eight assembly methods are provided, but there are other methods as well, as detailed below:

[0101] Assembly Method 1: Assemble two first-type unit cells 110 with one second-type unit cell 120. Specifically, first assemble the vertical groove 111 on the eighth surface of the second-type unit cell 120 with the vertical protrusion 103 on the fifth surface of the right-side first-type unit cell 110. Then assemble the vertical groove 111 on the second surface of the left-side first-type unit cell 110 with the vertical protrusion 103 on the eleventh surface of the second-type unit cell 120. This completes the assembly of the first assembly 210. Figure 7 As shown.

[0102] Assembly Method Two: Assemble the second assembly 220 based on the first assembly 210. Specifically, assemble the transverse groove 112 on the eighteenth surface of the third type of unit cell 130 with the transverse protrusion 104 on the third surface of the first type of unit cell 110 on the right side of assembly 1. Repeat the same process on the other side to complete the assembly of the second assembly 220. Figure 8 As shown.

[0103] Assembly Method 3: Assemble the third assembly 230 based on the second assembly 220. Specifically, assemble the transverse groove 112 on the sixth surface of the first type of unit cell 110 with the transverse protrusion 104 on the eighteenth surface of the third type of unit cell 130 on the right side of the second assembly 220. Repeat the same process on the other side to complete the assembly of the third assembly 230. Figure 9 As shown.

[0104] Assembly Method 4: Assemble the fourth assembly 240 based on the third assembly 230. Specifically, align the vertical protrusion 103 on the eleventh surface of the second type of unit cell 120 with the vertical groove 111 on the second surface of the first type of unit cell 110 on the left side of the third assembly 230. Simultaneously, align the vertical groove 111 on the eighth surface of the second type of unit cell 120 with the vertical protrusion 103 on the fifth surface of the first type of unit cell 110 on the right side of the third assembly 230. After aligning both sides simultaneously, assemble the fourth assembly 240. Figure 10 As shown.

[0105] Assembly Method 5: Assemble the fifth assembly 250 based on the fourth assembly 240. The specific assembly method is as follows: Rotate the first type of unit cell 110 so that its third surface is in front. After the first type of unit cell 110 is rotated, the horizontal and vertical relationship will change accordingly. At this time, the front surface of the first type of unit cell 110 is a horizontal convex beam 104, the right surface is a vertical groove 111, the upper surface is a vertical convex beam 103, the rear surface is a horizontal groove 112, the left surface is a vertical convex beam 103, and the lower surface is a vertical groove 111. For easy distinction, the first type of unit cell 110 at this time is named the new type of unit cell 150.

[0106] The characterization of the new type of unit cell 150 is defined as follows, with the corresponding surfaces corresponding sequentially. Specifically, the front surface is the nineteenth surface, with a transverse convex beam 104; the right surface is the twentieth surface, with a vertical groove 111; the upper surface is the twenty-first surface, with a vertical convex beam 103; the rear surface is the twenty-second surface, with a transverse groove 112; the left surface is the twenty-third surface, with a vertical convex beam 103; and the lower surface is the twenty-fourth surface, with a vertical groove 111.

[0107] Align the transverse groove 112 on the 22nd surface of the new type of unit cell 150 with the transverse protrusion 104 on the 17th surface of the third type of unit cell 130 in the middle of the right side of the fourth assembly 240.

[0108] Align the vertical protrusion 103 on the twenty-third surface of the new type of unit cell 150 with the vertical groove 111 on the twelfth surface of the second type of unit cell 120 in the middle of the upper side of the fourth assembly 240.

[0109] Align the transverse protrusion 104 on the nineteenth surface of the new type of unit cell 150 with the transverse groove 112 on the fourteenth surface of the third type of unit cell 130 in the middle of the left side of the fourth assembly 240.

[0110] Align the vertical groove 111 on the twentieth surface of the new type of unit cell 150 with the vertical protrusion 103 on the ninth surface of the second type of unit cell 120 in the middle of the lower side of the fourth assembly 240.

[0111] After aligning the four pairs of protruding beams and grooves, assembly can proceed. This step locks the eight unit cells containing the fourth assembly 240 into assembly. At this point, only the new type of unit cell 150 has out-of-plane degrees of freedom. The assembled fifth assembly 250, as shown... Figure 11 As shown.

[0112] Assembly Method Six: Assemble the sixth assembly 260 based on the fourth assembly 240. Specifically, since the front surface of the fourth assembly 240 is a vertical protruding beam 103 and the rear surface is a vertical groove 111, multiple fourth assemblies 240 can be easily assembled. Taking a three-layer assembly as an example, but not limited to three layers, the three fourth assemblies 240 are assembled by sequentially assembling the front vertical protruding beam 103 and the rear vertical groove 111, thus obtaining the sixth assembly 260. Figure 12 As shown.

[0113] Assembly Method Seven: Assemble three new type-one cells 150 sequentially, one in front of the other, to obtain the seventh assembly 270. The assembly can be performed using three new type-one cells 150, but is not limited to three. Specifically, the assembly method is as follows: the vertical groove 111 on the twenty-fourth surface of the new type-one cell 150 located at the front is assembled with the vertical protrusion 103 on the twenty-first surface of the new type-one cell 150 located at the rear to obtain the seventh assembly 270. Figure 13 As shown.

[0114] Assembly Method 8: Assemble the seventh assembly 270 and the sixth assembly 260 to obtain the eighth assembly 280. Taking a three-layer assembly as an example, but not limited to three layers, the specific assembly method is as follows:

[0115] Align the transverse groove 112 on the twenty-second surface of the seventh assembly 270 with the transverse protrusion 104 on the seventeenth surface of the three third-class unit cells 130 in the middle right side of the sixth assembly 260.

[0116] Align the vertical protrusion 103 on the twenty-third surface of the seventh assembly 270 with the vertical groove 111 on the twelfth surface of the three second-type unit cells 120 in the middle of the upper side of the sixth assembly 260.

[0117] Align the transverse protrusion 104 on the nineteenth surface of the seventh assembly 270 with the transverse groove 112 on the fourteenth surface of the three third-class unit cells 130 in the middle left side of the sixth assembly 260.

[0118] Align the vertical groove 111 on the twentieth surface of the seventh assembly 270 with the vertical protrusion 103 on the ninth surface of the three second-type unit cells 120 in the middle of the lower side of the sixth assembly 260.

[0119] Similar to the assembly method of the fifth assembly 250, assembly can proceed after aligning the four pairs of protruding beams and grooves. This step locks the 24 unit cells containing the sixth assembly 260 into place. At this point, only the seventh assembly 270 has out-of-plane degrees of freedom. The assembled eighth assembly 280, as shown... Figure 14 As shown.

[0120] Among them, small assemblies are formed by assembling three types of unit cells 100, such as Figure 7 , Figure 8 , Figure 9 and Figure 10 Building upon this, through pin-type intermediates, such as the new unit cell 150 and the seventh assembly, rapid locking of single-layer and multi-layer structures is achieved, enabling the assembly into large assemblies, such as... Figure 11 , Figure 13 and Figure 14 .

[0121] Finally, it should be noted that other embodiments of this application will readily conceive of by those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and alterations may be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A unit cell for assembling lattice metamaterial structures, characterized in that, The unit cell includes: The outer frame is a cubic structure and includes three sets of opposing surfaces. Each surface has two sets of opposing sides. For two surfaces belonging to the same set, one set of sides of one surface has a connecting beam extending along the side, and the corresponding set of sides of the other surface has a connecting groove extending along the side. The cross-section of the connecting groove is non-circular and is a continuous arc. The connecting beam has an embedding part that is adapted to the cross-sectional shape of the connecting groove. A support component is disposed within the space enclosed by the outer frame and is used to support the outer frame.

2. The unit cell according to claim 1, characterized in that, Both the connecting groove and the embedded part have elliptical cross-sections.

3. The unit cell according to claim 2, characterized in that, The connecting beam further includes a base portion for connecting with the outer frame, wherein the outer peripheral wall of the base portion is connected to the outer peripheral wall of the embedded portion and smoothly transitions.

4. The unit cell according to claim 2, characterized in that, The ellipse has a major axis and a minor axis, and the ratio of the length of the major axis to the length of the minor axis is 1.5-3.

5. The unit cell according to any one of claims 1-4, characterized in that, The outer frame includes a front surface and a rear surface that are opposite each other in the front-back direction, a left surface and a right surface that are opposite each other in the left-right direction, and an upper surface and a lower surface that are opposite each other in the up-down direction. The left and right sides of the front surface are respectively provided with connecting beams extending in the vertical direction; The front and rear sides of the right surface are respectively provided with connecting grooves extending in the vertical direction; The front and rear sides of the upper surface are respectively provided with connecting beams extending in the left and right directions.

6. The unit cell according to any one of claims 1-4, characterized in that, The outer frame includes a front surface and a rear surface that are opposite each other in the front-back direction, a left surface and a right surface that are opposite each other in the left-right direction, and an upper surface and a lower surface that are opposite each other in the up-down direction. The left and right sides of the front surface are respectively provided with connecting beams extending in the vertical direction; The front and rear sides of the right surface are respectively provided with connecting grooves extending in the vertical direction; The upper surface is provided with connecting beams extending in the front-to-back direction on the left and right sides respectively.

7. The unit cell according to any one of claims 1-4, characterized in that, The outer frame includes a front surface and a rear surface that are opposite each other in the front-back direction, a left surface and a right surface that are opposite each other in the left-right direction, and an upper surface and a lower surface that are opposite each other in the up-down direction. The left and right sides of the front surface are respectively provided with connecting beams extending in the vertical direction; The upper and lower sides of the right surface are respectively provided with connecting grooves extending in the front-to-back direction; The front and rear sides of the upper surface are respectively provided with connecting beams extending in the left and right directions.

8. The unit cell according to claim 1, characterized in that, The support assembly includes multiple support columns corresponding to the corners of the outer frame, with the multiple support columns extending from the corresponding corners toward the geometric center of the outer frame and connecting thereto.

9. A lattice metamaterial structure, characterized in that, include: The unit cell according to any one of claims 1-8, wherein there are multiple unit cells, and the two opposite surfaces of two adjacent unit cells are connected by the connecting protrusions embedded in the connecting grooves.

10. The lattice metamaterial structure according to claim 9, characterized in that, The lattice metamaterial structure includes at least one of a first type of unit cell, a second type of unit cell, and a third type of unit cell; Among them, the left and right sides of the front surface of the first type of unit cell are respectively provided with connecting protrusions extending in the vertical direction, the front and rear sides of the right surface are respectively provided with connecting grooves extending in the vertical direction, and the front and rear sides of the upper surface are respectively provided with connecting protrusions extending in the horizontal direction. The second type of unit cell has connecting protrusions extending in the vertical direction on the left and right sides of the front surface, connecting grooves extending in the vertical direction on the front and rear sides of the right surface, and connecting protrusions extending in the front and rear directions on the left and right sides of the upper surface. The third type of unit cell has connecting protrusions extending in the vertical direction on the left and right sides of its front surface, connecting grooves extending in the front and back direction on the upper and lower sides of its right surface, and connecting protrusions extending in the left and right direction on the front and rear sides of its upper surface.

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