Method for designing oblique prismatic table type polyhedral sheared-folded paper metamaterial based on weaving self-locking

Abstract

The invention discloses a design method of an oblique prismatic table type polyhedral shear-folded paper metamaterial based on weaving self-locking. According to the method, by designing a weaving-fold shear-origami pattern inspired by lattice dislocation, a slippage dislocation overlapping forming mode of oblique pyramid frustum type polyhedral shear-origami body cells is established, and a closed-loop polyhedral filling unit with multiple body cells connected end to end is established according to bottom surface polygon single-point filling angle constraint and polyhedral symmetry of the polyhedral body cells; weaving self-locking of the oblique prismatic table type polyhedral shear-folding paper structure is achieved, the problem that the shape cannot be locked in the overlapping process of the polyhedral shear-folding paper body cells is solved, the mirror image stacked shear-folding paper structure is designed through crease valley / ridge type replacement, and the problem that stacking and assembling cannot be achieved due to the fact that the top faces and the bottom faces of the oblique prismatic table type polyhedral body cells are not parallel is solved. And a design basis is provided for the combined layout of the oblique prismatic table type polyhedral shear-origami metamaterial with a self-locking characteristic.

Description

Technical Field

[0001] The present invention belongs to the field of metamaterial design, and in particular relates to a design method of an oblique pyramid-shaped polyhedron shear-origami metamaterial based on braided self-locking. Background Art

[0002] Metamaterials are synthetic materials with unique microstructures. Through their microstructure, they impart unique properties beyond those of traditional materials, offering new insights and approaches to solving material challenges in various engineering applications. Self-locking metamaterials emerged in this context.

[0003] Self-locking metamaterials aim to achieve self-locking properties under specific conditions through structural design and material combinations. This means they can automatically lock into a certain state after being subjected to a certain external force, while also maintaining other desirable properties, such as high load-bearing capacity, good flexibility, or energy absorption. For example, origami metamaterials, through the ingenious design of the origami structure, can achieve a unique deformation mode of "compression, rotation, and tension." This deformation mode allows the origami structure to fold when subjected to in-plane loads, exhibiting excellent flexibility and deformability, while in out-of-plane directions it can withstand loads thousands or even tens of thousands of times its own weight, demonstrating excellent load-bearing capacity. Summary of the Invention

[0004] To overcome the shortcomings of the existing technology, the present invention aims to provide a design method for a slanted pyramid polyhedron shear-origami metamaterial based on braiding and self-locking. This method designs a braid-fold shear-origami pattern inspired by lattice disclination, thereby establishing a slip-displacement and superposition formation pattern for the slanted pyramid polyhedron shear-origami cells, achieving braided self-locking of the pyramid polyhedron cells. Furthermore, by folding and concealing redundant material, a variable-height slanted pyramid polyhedron shear-origami single-layer folded structure is designed, which can then be inverted to form a sandwich-like composite structure.

[0005] The technical solutions of the present invention are as follows:

[0006] 1. An oblique pyramid shear-origami cell

[0007] The oblique pyramid shear-origami cell includes a top surface, which is an axisymmetric structure, and corresponding side surfaces are arranged at each edge of the top surface; when the oblique pyramid shear-origami cell is in an unfolded state, a corresponding inner splicing block is further arranged between two adjacent side surfaces, the bottom edge of the inner splicing block is two sides and these two sides form an inwardly concave angle, and a corresponding outer splicing block is further arranged at the bottom edge of each side surface; during the folding process of the oblique pyramid shear-origami cell, all the inner splicing blocks fold inward, and when the oblique pyramid shear-origami cell is in a fully folded state, the bottom surface formed by the oblique pyramid shear-origami cell is an axisymmetric structure, and a surface angle is formed between the bottom surface and the top surface, thereby forming an oblique pyramid-like structure.

[0008] Optionally, the bottom surface is a symmetrical n-gon, and the top surface is a symmetrical n-gon; or the bottom surface is a symmetrical 2n-gon, and the top surface is a symmetrical n-gon, where n≥3.

[0009] 2. A Design Method for an Oblique Pyramid Shear-Origami Cell

[0010] Obtain the number of all side faces and the corresponding bottom and side lengths of each side face, and calculate the top lengths of all side faces and the sizes of all inner and outer pieces based on the corresponding bottom and side lengths of each side face, thereby completing the design of the oblique pyramid shear-origami cell.

[0011] 3. A design method for oblique pyramid-shaped polyhedron shear-origami metamaterial based on braided self-locking

[0012] The height between the top and bottom surfaces of the oblique pyramid shear-origami cell is obtained and recorded as the cell height. The oblique pyramid shear-origami cell is in a folded state. A single-layer oblique pyramid polyhedron shear-origami metamaterial is designed according to the cell height.

[0013] Optionally, designing a single-layer oblique pyramid-shaped polyhedron scissors-origami metamaterial according to the soma cell height includes:

[0014] A single-layer oblique pyramid polyhedron scissor-origami metamaterial is formed by laying a plurality of identical oblique pyramid scissor-origami cells in sequence.

[0015] Optionally, designing a single-layer oblique pyramid-shaped polyhedron scissors-origami metamaterial according to the soma cell height includes:

[0016] A single-layer oblique pyramid shear-origami metamaterial is formed by laying down several oblique pyramid shear-origami cells with the same cell height.

[0017] Optionally, designing a single-layer oblique pyramid-shaped polyhedron scissors-origami metamaterial according to the soma cell height includes:

[0018] Different oblique pyramid shear-origami cells are laid in sequence at the same density to form a single-layer oblique pyramid polyhedron shear-origami metamaterial.

[0019] 4. A design method for oblique pyramid-shaped polyhedron shear-origami metamaterial based on braided self-locking

[0020] The height between the top and bottom surfaces of the oblique pyramid shear-origami cell is obtained and recorded as the cell height, wherein the oblique pyramid shear-origami cell is in a folded state. A single-layer oblique pyramid-type polyhedron shear-origami metamaterial is designed according to the cell height, one single-layer oblique pyramid-type polyhedron shear-origami metamaterial is upright, and another single-layer oblique pyramid-type polyhedron shear-origami metamaterial is inverted. The inverted single-layer oblique pyramid-type polyhedron shear-origami metamaterial is then placed on the upright single-layer oblique pyramid-type polyhedron shear-origami metamaterial, thereby forming a metamaterial with a sandwich-like composite structure, wherein the upper surface of the inverted single-layer oblique pyramid-type polyhedron shear-origami metamaterial is parallel to the lower surface of the upright single-layer oblique pyramid-type polyhedron shear-origami metamaterial.

[0021] 5. A computer device

[0022] The device includes a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the method when executing the computer program.

[0023] 6. A Computer-Readable Storage Medium

[0024] The medium stores a computer program, which implements the steps of the method when executed by a processor.

[0025] Beneficial effects of the present invention:

[0026] The present invention combines lattice paper cutting and sandwich-type composite structures to design a weaving-pleating shear-origami pattern inspired by lattice disclination; the present invention establishes a slip dislocation and superposition formation mode of oblique pyramid-type polyhedron shear-origami cells to achieve the weaving self-locking of the prism-shaped polyhedron cells; by folding and hiding redundant materials, a variable-height oblique pyramid-type polyhedron shear-origami single-layer structure is designed, and it is inverted to form a sandwich-type composite structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Schematic diagram of the oblique pyramid weaving-pleating shear-origami body cell, where (a) is a 6-3 type oblique pyramid shear-origami body cell, (b) is a 3-3 type oblique pyramid shear-origami body cell, (c) is an 8-4 type oblique pyramid shear-origami body cell, (d) is a 4-4 type oblique pyramid shear-origami body cell, (e) is a 10-5 type oblique pyramid shear-origami body cell, and (f) is a 5-5 type oblique pyramid shear-origami body cell.

[0028] Figure 2 Schematic diagrams of different states of the oblique pyramid polyhedron cell, where (a) is the unfolded state of the 6-3 type oblique pyramid shear-origami cell, (b) is the folded state of the 6-3 type oblique pyramid shear-origami cell, (c) is the unfolded state of the 3-3 type oblique pyramid shear-origami cell, and (d) is the folded state of the 3-3 type oblique pyramid shear-origami cell.

[0029] Figure 3 It is an irregular {3,6,3,6} weave-pleat-shear-origami polyhedron filling unit.

[0030] Figure 4 Schematic diagram of the model of the oblique pyramid sandwich composite structure plate, where (a) is a 6-3 type oblique pyramid polyhedron shear-origami single-layer structure, (b) is a mirror-stacked 6-3 type sandwich composite structure, (c) is a {3,6,3,6} oblique pyramid polyhedron shear-origami single-layer structure, and (d) is a mirror-stacked {3,6,3,6} oblique pyramid sandwich composite structure plate.

[0031] Figure 5 Schematic diagrams of Example 1, wherein (a) is a schematic diagram of a 6-3 type oblique pyramid shear-origami cell, and (b) is a schematic diagram of a 3-3 type oblique pyramid shear-origami cell.

[0032] Figure 6 It is the irregular {3,6,3,6} weaving-pleat shear-origami polyhedron filling unit of Example 1.

[0033] Figure 7 This is the sandwich composite structural panel of Example 1.

[0034] Figure 8 Schematic diagrams of Example 2, wherein (a) is a schematic diagram of a 6-3 type oblique pyramid shear-origami cell, and (b) is a schematic diagram of a 3-3 type oblique pyramid shear-origami cell.

[0035] Figure 9 It is the irregular {3,6,3,6} weaving-pleat shear-origami polyhedron filling unit of Example 2.

[0036] Figure 10 This is the sandwich composite structural panel of Example 2. DETAILED DESCRIPTION

[0037] The present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0038] The oblique pyramid shear-origami cell proposed in the present invention includes a top surface, which is an axially symmetrical structure, and corresponding side surfaces are arranged at each edge of the top surface; when the oblique pyramid shear-origami cell is in an expanded state, a corresponding inner splicing block is further arranged between two adjacent side surfaces, that is, a corresponding inner splicing block is arranged at each top corner of the top surface, the bottom edge of the inner splicing block is two sides, and these two sides form an inwardly concave angle, and a valley fold is formed in the inner splicing block, and the position of the valley fold is on the angle bisector of the top angle of each inner splicing block (that is, the angle formed by the side edges of two adjacent side surfaces), and a corresponding outer splicing block is further arranged at the bottom edge of each side surface, the top angle of the outer splicing block coincides with a top angle of the corresponding side surface, and one edge of the outer splicing block coincides, does not coincide, or partially coincides with the bottom edge of the corresponding side surface. Specifically, if the body cell is of 2n-n type, one edge of the outer splicing block coincides with the bottom edge of the corresponding side surface; if the body cell is of nn type, one edge of the outer splicing block may or may not coincide with the bottom edge of the corresponding side surface. Different outer splicing blocks are set at the same vertex angle of the corresponding side surface. The outer splicing blocks are used to splice with the inner splicing blocks of different body cells when constructing a single-layer oblique pyramid-type polyhedron shear-origami metamaterial. The bottom edges of all side surfaces are also used as valley folds, which are represented by dotted lines in the figure. The bottom edges of all inner splicing blocks of each body cell are used as shear lines (that is, the two edges forming the concave angle), which are represented by thick solid lines in the figure. The other edges are ridge creases, which are represented by ordinary solid lines in the figure. During the folding process of the oblique pyramid-type scissors-origami cell, all internal splicing blocks fold inward. When the oblique pyramid-type scissors-origami cell is in a fully folded state, the bottom surface formed by the oblique pyramid-type scissors-origami cell is an axisymmetric structure, and a surface angle is formed between the bottom surface and the top surface, that is, the bottom surface and the top surface are not parallel, and several side surfaces are set between the bottom surface and the top surface. All internal splicing blocks are located inside the structure, thereby forming a quasi-oblique pyramid structure, that is, all side surfaces serve as side surfaces of the quasi-oblique pyramid structure.

[0039] The bottom surface is a symmetrical n-gon, and the top surface is a symmetrical n-gon; or the bottom surface is a symmetrical 2n-gon, and the top surface is a symmetrical n-gon, where n≥3.

[0040] Figure 1 Schematic diagram of the oblique pyramid weaving-fold shear-origami cell, where Figure 1 (a) is a 6-3 type oblique pyramid shear-origami cell, Figure 1 (b) is a 3-3 type oblique pyramid shear-origami cell, Figure 1 (c) is an 8-4 type oblique pyramid shear-origami cell, Figure 1 (d) is a 4-4 type oblique pyramid shear-origami cell, Figure 1 (e) is a 10-5 type oblique pyramid shear-origami cell, Figure 1 (f) is a 5-5 type oblique pyramid shear-origami cell.

[0041] The present invention provides a method for designing an oblique pyramid shear-origami somatic cell, comprising the following steps:

[0042] Obtain the number of all sides and the corresponding base and side lengths of each side. If the side is triangular, also obtain the vertex angle of the side. Based on the corresponding base and side lengths of each side, calculate the top lengths of all sides and the dimensions of all inner and outer pieces, thus completing the design of the oblique pyramid shear-origami cell.

[0043] For a 2n-n type oblique pyramid shear-origami cell, the number of sides of the base is recorded as 2n. Based on the number of all sides and the corresponding base and side lengths of each side, and the vertex angle of the triangular side, the following formula can be derived:

[0044]

[0045]

[0046] Where i = 1, ..., 2n, β is the bisector angle of the top angle of each inner splicing block, a i is the length of the base of the i-th side, that is, the length of each side of the bottom polygon; α i is the angle formed by the two sides of the i-th side, x is the length of the ridge crease, The length of the longer diagonal of the outer splicing block, is the angle of the concave bottom edge of the i-th inner splicing block, is the length of the first bottom side of the i-th inner splicing block, is the length of the second bottom side of the i-th inner splicing block, c i is the valley crease length of the i-th inner splicing block; j = 1,…,n, a 2j is the length of the base of the j-th side, that is, the length of each side of the bottom polygon; α 2j is the angle formed by the two sides of the j-th side, is the angle of the indentation in the bottom edge of the j-th inner splicing block, is the length of the first bottom side of the j-th inner splicing block, is the length of the second bottom side of the j-th inner splicing block, d j is the length of the top side of the i-th side. In a feasible implementation, a1 is the base of any triangle side, i.e. a1, a3, ..., a 2n-1 can be used to calculate the length of the ridge crease in each inner splice.

[0047] In a feasible implementation, the upper left corner or the topmost inner block of the soma is numbered 1, and the length of its corresponding bottom side is numbered a1, such as Figure 1 (a) and Figure 1 As shown in (c).

[0048] Let the top surface area of ​​the pyramid be S 上 , the bottom area is recorded as S 下 , let the cell tiling area be S, the material thickness be t, and the relative density of the cell in the fully folded state be ρ, so ρ=S×t / (S 下 H), let the height of the pyramidal soma in the fully folded state be H, that is, the soma height, and H = (H1 + H2) / 2, where H1 is the height from the vertex in one vertex plane of the top surface to the bottom surface, and H2 is the height from the vertex in the other vertex plane of the top surface to the bottom surface. Since the top surface is a symmetrical structure, all vertices on the top surface are located in two vertex planes respectively. The angle between the top and bottom surfaces of the soma is denoted as δ. The absolute value of the difference between H1 and H2 is divided by the length of the central axis of the n-gon on the top surface and then the inverse sine function is taken as the whole to obtain the angle δ. The formula is as follows:

[0049]

[0050] For an nn-type oblique pyramid shear-origami cell, the number of bottom edges is recorded as n. Based on the number of all sides and the corresponding bottom and side lengths of each side, the following formula can be derived:

[0051] If n is an odd number, then If n is an even number, then

[0052] The omitted formula is the same as that of the 2n-n type.

[0053] The present invention proposes a method for designing an oblique pyramid-shaped polyhedron shear-origami metamaterial based on braided self-locking, which specifically includes the following steps:

[0054] The height between the top and bottom surfaces of the pyramidal shear-origami cell is calculated and recorded as the cell height. Each pyramidal shear-origami cell is folded. Based on this cell height, a single-layer pyramidal polyhedron shear-origami metamaterial is designed. Cells are sequentially connected, with the inner and outer tiles of adjacent cells sharing a common edge.

[0055] In a feasible embodiment, designing a single-layer oblique pyramid-shaped polyhedron shear-origami metamaterial according to the cell height includes:

[0056] A single-layer oblique pyramid polyhedron scissor-origami metamaterial is formed by laying out a number of identical oblique pyramid scissor-origami cells in sequence.

[0057] In a feasible embodiment, designing a single-layer oblique pyramid-shaped polyhedron shear-origami metamaterial according to the cell height includes:

[0058] A single-layer oblique pyramid shear-origami metamaterial is formed by laying down a number of oblique pyramid shear-origami cells with the same cell height but different other dimensions (the other dimensions may be all different or partially different) in sequence.

[0059] In a feasible embodiment, designing a single-layer oblique pyramid-shaped polyhedron shear-origami metamaterial according to the cell height includes:

[0060] Different oblique pyramid shear-origami cells are laid in sequence at the same density to form a single-layer oblique pyramid polyhedron shear-origami metamaterial.

[0061] The present invention proposes a method for designing an oblique pyramid-shaped polyhedron shear-origami metamaterial based on braided self-locking, which specifically includes the following steps:

[0062] Obtain the height between the top and bottom surfaces of the oblique pyramid shear-origami cell and record it as the cell height. The oblique pyramid shear-origami cell is in a folded state. According to the cell height, a single-layer oblique pyramid polyhedron shear-origami metamaterial is designed. Solidworks is used to place a single-layer oblique pyramid polyhedron shear-origami metamaterial upright, and another single-layer oblique pyramid polyhedron shear-origami metamaterial inverted. Then, the inverted single-layer oblique pyramid polyhedron shear-origami metamaterial is placed on the upright single-layer A metamaterial of sandwich-like composite structure is formed on the oblique pyramid-type polyhedron shears-origami metamaterial, wherein the upper surface of the inverted single-layer oblique pyramid-type polyhedron shears-origami metamaterial is parallel to the lower surface of the upright single-layer oblique pyramid-type polyhedron shears-origami metamaterial, that is, the bottom surface of the inverted single-layer oblique pyramid-type polyhedron shears-origami metamaterial is parallel to the bottom surface of the upright single-layer oblique pyramid-type polyhedron shears-origami metamaterial, and the top surfaces of some or all of the oblique pyramid shears-origami cells of the two are in contact.

[0063] Figure 2 Schematic diagram of different states of the oblique pyramid polyhedron cell, where Figure 2 (a) is the unfolded state of the 6-3 type oblique pyramid shear-origami cell. Figure 2 (b) is the folded state of the 6-3 type oblique pyramid shear-origami cell. Figure 2 (c) is the unfolded state of the 3-3 type oblique pyramid shear-origami cell. Figure 2 (d) is the folded state of the 3-3 type oblique pyramid shear-origami cell.

[0064] Figure 3 is an irregular {3,6,3,6} weave-fold shear-origami polyhedron filling unit. The solid lines are ridge creases, the dashed lines are valley creases, and the thick solid lines are shear lines. Figure 3 After folding, a single-layer oblique pyramid-shaped polyhedron shear-origami metamaterial (such as Figure 4 (as shown in (c)).

[0065] Figure 4 Schematic diagram of the model of the oblique pyramid sandwich composite structure plate, that is, the sandwich composite structure metamaterial. Figure 4 (a) is a 6-3 type oblique pyramid type polyhedron shear-origami single layer structure, Figure 4 (b) is a 6-3 type sandwich composite structure with mirror stacking. Figure 4 (c) is a {3,6,3,6} oblique pyramid type polyhedron shear-origami single layer structure, Figure 4 (d) is a mirror-stacked {3,6,3,6} oblique pyramid sandwich composite structure plate.

[0066] Example 1: Highly consistent irregular {3,6,3,6} sandwich composite structure board

[0067] For the 6-3 type polyhedron, the lower base has six vertices and the upper top has three vertices. A symmetrical hexagon is selected as the lower base of the oblique pyramid type polyhedron; an isosceles triangle is selected as the upper top of the oblique pyramid type polyhedron. The initial values ​​are a1 = 72.26, a4 = 133.08mm, a2 = 155.03mm, α1 = 22.57°, α4 = 26.01°, α2 = 31.16°,

[0068] In this way, we can calculate x = 184.63 mm. c1 = 147.55 mm, c2 = 147.55 mm, c3 = 143.32 mm, d2 = 49.98 mm, d1 = 55.87 mm. Calculate H using the following equation:

[0069]

[0070] We can get H1 = 165.3mm, H2 = 164mm, then the height H = 164.65mm, the angle between the upper and lower surfaces δ = 1.49°, and the somatic cell tiling area S = 121410mm 2 , the lower base area S of the oblique pyramid when fully folded 下 =30020mm 2 , assuming the material thickness is 0.1 mm, the relative density of the cell in the fully folded state is ρ = 0.0025, as Figure 5 As shown in (a).

[0071] For a 3-3 polyhedron, the bottom base is three vertices and the top is three vertices. An isosceles triangle is selected as the bottom base of the oblique pyramid polyhedron; an isosceles triangle is selected as the top top of the oblique pyramid polyhedron. The initial values ​​are a1 = 650mm, a2 = 718.63mm, α1 = 99°, α2 = 115°,

[0072] In this way, we can calculate x = 400mm, β = 8, c1=163.55mm,c2=163.55mm,d1=40.14mm。Calculate H by the following equation:

[0073]

[0074] The calculated values ​​are H1 = 165.8 mm, H2 = 163.5 mm, so the height H = 164.65 mm, the angle between the upper and lower surfaces δ = 3.95°, and the somatic cell tiling area S = 486270 mm. 2 , the lower base area S of the oblique pyramid when fully folded 下 =194630mm 2 , assuming the material thickness is 0.1 mm, the relative density of the cell in the fully folded state is ρ = 0.0015, as Figure 5 As shown in (b).

[0075] Select two 6-3 type and two 3-3 oblique pyramid type polyhedron cells and connect them end to end to form a {3,6,3,6} braided-pleated polyhedron filling unit (such as Figure 6 As shown) and folded to form an oblique pyramid type polyhedron shear-origami single-layer folded structure, and one of the pieces is inverted to form a sandwich type composite structure plate (as shown) Figure 7 shown).

[0076] Example 2: Irregular {3,6,3,6} sandwich composite structure board with consistent relative cell density

[0077] For the 6-3 type polyhedron, the lower base has six vertices and the upper top has three vertices. A symmetrical hexagon is selected as the lower base of the oblique pyramid type polyhedron; an isosceles triangle is selected as the upper top of the oblique pyramid type polyhedron. The initial values ​​are a1 = 72.26, a4 = 133.08 mm, a2 = 155.03 mm, α1 = 22.57°, α4 = 26.01°, α2 = 31.16°.

[0078] In this way, we can calculate x = 184.63 mm, β = 17°, c1=147.55mm,c2=147.55mm,c3=143.32mm,d2=49.98mm,d1=55.87mm,H1=165.3mm,H2=164mm,height H=164.65mm,angle δ=1.49°,cell tiling area S=121410mm 2, the lower base area S of the oblique pyramid when fully folded 下 =30020mm 2 , assuming the material thickness is 0.1 mm, the relative density of the cell in the fully folded state is ρ = 0.0025, as Figure 8 As shown in (a).

[0079] For a 3-3 polyhedron, the bottom base is three vertices and the top is three vertices. An isosceles triangle is selected as the bottom base of the oblique pyramid polyhedron; an isosceles triangle is selected as the top top of the oblique pyramid polyhedron. The initial values ​​are a1 = 350mm, a2 = 394.9mm, α1 = 84°, α2 = 99°,

[0080] In this way, we can calculate x = 200mm, both β = 16°, Mountain c1 = 367.31mm, c2 = 367.31mm, d1 = 83.54mm, H1 = 121mm, H2 = 116mm, height H = 118.5mm, angle between upper and lower surfaces δ = 4.09°, cell tiling area S = 171250mm 2 , the lower base area S of the oblique pyramid when fully folded 下 =57060mm 2 , assuming the material thickness is 0.1 mm, the relative density of the cell in the fully folded state is ρ = 0.0025, as Figure 8 As shown in (b).

[0081] Select two 6-3 type and two 3-3 oblique pyramid type polyhedron cells to connect the polyhedron end to end to form a {3,6,3,6} braided-pleated polyhedron filling unit (such as Figure 9 As shown) and folded to form an oblique pyramid type polyhedron shear-origami single-layer folded structure, and one of the pieces is inverted to form a sandwich type composite structure plate (as shown) Figure 10 shown).

[0082] The present invention designs a weaving-pleating scissors-origami pattern inspired by lattice disclination, establishes a slip dislocation and superposition formation mode of an oblique pyramid-type polyhedron scissors-origami cell, establishes a closed-loop polyhedron filling unit with polyhedron cells connected end to end based on the single-point filling angle constraint of the bottom polygon and the multi-axis symmetry of the polyhedron cell, and proposes a combined layout method of 2n-n and nn-type oblique pyramid-type polyhedron scissors-origami cell circumference mixed filling with Burgers modulus as a constraint condition, realizes the weaving self-locking of the oblique pyramid-type polyhedron scissors-origami structure, solves the problem that the shape cannot be locked during the superposition process of the polyhedron folding-cissors-origami cell, designs a mirror-image stacked scissors-origami structure by crease valley / ridge type replacement, solves the problem that the top surface and bottom surface of the oblique pyramid-type polyhedron cell are not parallel, resulting in the inability to stack and assemble, and provides a design basis for the combined layout of oblique pyramid-type polyhedron scissors-origami metamaterials with self-locking properties.

Claims

1. An oblique pyramid shear-origami cell, characterized in that: The oblique pyramid shear-origami cell includes a top surface, which is an axisymmetric structure, and corresponding side surfaces are arranged at each edge of the top surface; when the oblique pyramid shear-origami cell is in an unfolded state, a corresponding inner splicing block is further arranged between two adjacent side surfaces, the bottom edge of the inner splicing block is two sides and these two sides form an inwardly concave angle, and a corresponding outer splicing block is further arranged at the bottom edge of each side surface; during the folding process of the oblique pyramid shear-origami cell, all the inner splicing blocks fold inward, and when the oblique pyramid shear-origami cell is in a fully folded state, the bottom surface formed by the oblique pyramid shear-origami cell is an axisymmetric structure, and a surface angle is formed between the bottom surface and the top surface, thereby forming an oblique pyramid-like structure.

2. The oblique pyramid shear-origami body cell according to claim 1, characterized in that: The bottom surface is a symmetrical n-gon, and the top surface is a symmetrical n-gon; or the bottom surface is a symmetrical 2n-gon, and the top surface is a symmetrical n-gon, where n≥3.

3. A design method for an oblique pyramid shear-origami cell, characterized in that: The following steps are involved: Obtain the number of all side faces and the corresponding bottom and side lengths of each side face, and calculate the top lengths of all side faces and the sizes of all inner and outer splicing blocks based on the corresponding bottom and side lengths of each side face, thereby completing the design of the oblique pyramid shear-origami cell described in claim 1.

4. A design method for a scissor-origami metamaterial of an oblique pyramidal polyhedron based on self-locking braiding, characterized in that: The following steps are involved: The height between the top and bottom surfaces of the oblique pyramid shear-origami cell according to claim 1 is obtained and recorded as the cell height, wherein the oblique pyramid shear-origami cell is in a folded state, and a single-layer oblique pyramid polyhedron shear-origami metamaterial is designed according to the cell height.

5. The design method of a scissor-origami metamaterial of an oblique pyramid-shaped polyhedron based on braided self-locking according to claim 4, characterized in that: The design of a single-layer oblique pyramid-shaped polyhedron shear-origami metamaterial according to the cell height includes: A single-layer oblique pyramid polyhedron scissor-origami metamaterial is formed by laying a plurality of identical oblique pyramid scissor-origami cells in sequence.

6. The design method of a scissor-origami metamaterial of an oblique pyramid-shaped polyhedron based on braided self-locking according to claim 4, characterized in that: The design of a single-layer oblique pyramid-shaped polyhedron shear-origami metamaterial according to the cell height includes: A single-layer oblique pyramid shear-origami metamaterial is formed by laying down several oblique pyramid shear-origami cells with the same cell height.

7. The design method of a scissor-origami metamaterial of an oblique pyramid-shaped polyhedron based on braided self-locking according to claim 4, characterized in that: The design of a single-layer oblique pyramid-shaped polyhedron shear-origami metamaterial according to the cell height includes: Different oblique pyramid shear-origami cells are laid in sequence at the same density to form a single-layer oblique pyramid polyhedron shear-origami metamaterial.

8. A design method for a scissor-origami metamaterial of an oblique pyramidal polyhedron based on self-locking braiding, characterized in that: The following steps are involved: The height between the top and bottom surfaces of the oblique pyramid shears-origami cell according to claim 1 is obtained and recorded as the cell height, wherein the oblique pyramid shears-origami cell is in a folded state, and a single-layer oblique pyramid-type polyhedron shears-origami metamaterial is designed according to the cell height. One single-layer oblique pyramid-type polyhedron shears-origami metamaterial is upright, and another single-layer oblique pyramid-type polyhedron shears-origami metamaterial is inverted. The inverted single-layer oblique pyramid-type polyhedron shears-origami metamaterial is then placed on the upright single-layer oblique pyramid-type polyhedron shears-origami metamaterial, thereby forming a metamaterial with a sandwich-like composite structure, wherein the upper surface of the inverted single-layer oblique pyramid-type polyhedron shears-origami metamaterial is parallel to the lower surface of the upright single-layer oblique pyramid-type polyhedron shears-origami metamaterial.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 3 to 8 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 3 to 8 are implemented.

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