A triangular rotating rigid body structure with compression-torsion characteristics

Abstract

The present invention relates to a triangular rotating rigid body structure with compression-torsion characteristics, which belongs to the field of mechanical metamaterials, and includes two tensegrity cellular structures, wherein the cellular structure includes two parts: a three-rod tensegrity structural component and a degree of freedom constraint component. Under the action of the three-rod and nine-cable tensegrity structure, when the structure is not subjected to external loads, the structure is subjected to the interaction of internal stresses and reaches equilibrium in a self-stable state; when subjected to external loads, the upper and lower surfaces of the cellular structure will produce a torsional effect, and once the external load is removed, the structure will return to its initial state. A triangular rotating rigid body structure with compression-torsion characteristics has the advantages of adaptability, self-recovery, indentation resistance characteristics, etc. The present invention combines the tensegrity structure with the mechanical metamaterial structure, enriches the types of existing mechanical metamaterial cellular structures, and opens up a new direction for the design, analysis and application of tensegrity mechanical metamaterial structures.

Description

Technical Field

[0001] The present invention belongs to the field of mechanical metamaterials and can be applied to the fields of robots, shock absorption, impact resistance, etc. More specifically, it relates to a triangular rotating rigid body structure with compression torsion characteristics. Background Art

[0002] Metamaterials are non-natural materials whose properties are derived from their structure rather than their chemical composition. They are artificial synthetic materials with special structures that exhibit very unique properties in the fields of mechanics, electromagnetic waves, sound waves, etc. According to the application field, metamaterials can be divided into four categories: electromagnetic metamaterials, acoustic metamaterials, thermal metamaterials, and mechanical metamaterials. Negative Poisson's ratio metamaterials are a branch of mechanical metamaterials. When subjected to pressure, the ratio of the lateral normal strain to the axial normal strain in a certain direction (Poisson's ratio) is negative. This material has many unique properties, such as highly controllable elasticity, light weight, high strength, etc., and can be used in various fields, such as robotics, medicine, aerospace, etc., making its research and application have great potential and has received widespread attention in recent years.

[0003] At present, the structural design of existing mechanical metamaterials has a single cellular structure, and negative Poisson's ratio metamaterials are mostly integrated structures with low reusability. In addition, many designs to date rely on the deformation or evolution of existing metamaterial structures, and it is impossible to systematically design geometric and topological shapes to obtain new metamaterial structures with negative Poisson's ratio effect.

[0004] Therefore, how to enrich the types of mechanical metamaterials and design a mechanical metamaterial that can be reused, has adjustable self-stiffness, and has adaptability, self-stability, and self-recovery is an urgent problem that technicians in this field need to solve. Summary of the invention

[0005] To this end, the present invention provides a triangular rotating rigid body structure with compression-torsion characteristics, which enriches the types of negative Poisson's ratio metamaterial cells and improves the mechanical properties of traditional mechanical metamaterials by combining the tensegrity structure with the mechanical metamaterial structure.

[0006] The present invention provides a triangular rotation rigid body structure with compression-torsion characteristics, comprising a first connecting axis and two tensioned cellular structures with different connection modes based on a three-bar tensioned structure: a first tensioned cellular structure and a second tensioned cellular structure; the first tensioned cellular structure has three groups, and the second tensioned cellular structure has three groups, thereby forming a six-cell structure of a triangular rotation rigid body structure with compression-torsion characteristics; the six-cell metamaterial structure is only one of the triangular rotation rigid body structures with compression-torsion characteristics, and the triangular rotation rigid body structure with compression-torsion characteristics includes other multi-cell structures of a negative Poisson's ratio metamaterial structure based on a three-bar tensioned structure that are formed by the first tensioned cellular structure and the second tensioned cellular structure, and are extended by the same connection mode as the first tensioned cellular structure and the second tensioned cellular structure in the six-cell metamaterial structure; except for the different connection modes, the first tensioned cellular structure and the second tensioned cellular structure have the same components and connection modes of the components.

[0007] Each group of the first tensile cell structure and each group of the second tensile cell structure include: a degree of freedom constraint component and a three-rod tensile integral structure component; the degree of freedom constraint component includes an equilateral triangle frame, a sliding component, a rod connector and a second connecting shaft; the three-rod tensile integral structure component includes a first tension elastic body, a second tension elastic body and a connecting rod; there are two groups of equilateral triangle frames, which are respectively placed at the upper and lower ends of the entire structure, and hinge holes are arranged at the outer edge positions of the three corners of the equilateral triangle frame. Three regular quadrangular prism structures are arranged in a 120° circular array inside the structure, and a hexagonal structure is arranged at the center of the structure and fixedly connected to the regular quadrangular prism structure. The function of the hinge hole position is to enable the cell structure to be hingedly connected through the hinge hole position, the regular quadrangular prism structure plays a guiding role, and the hexagonal structure in the middle plays a limiting role.

[0008] Each group of the first tension cell structure and each group of the second tension cell structure include: there are six groups of sliding parts, which are respectively installed on the regular quadrangular prism structures of the two groups of equilateral triangular frames, and the lower end of the sliding parts is designed with a short axis; there are six groups of rod connectors, and the upper end surface of the structure is provided with a through hole, which cooperates with the short axis of the lower end of the sliding part to achieve free rotation; the three groups of sliding parts fixed on the regular quadrangular prism structure of the equilateral triangular frame below and the three groups of sliding parts fixed on the regular quadrangular prism structure of the equilateral triangular frame above are arranged in opposite directions, and the three groups of rod connectors rotatably connected to the three groups of sliding parts below and the three groups of rod connectors rotatably connected to the three groups of sliding parts above are arranged in opposite directions; there are six groups of second connecting shafts; there are six groups of the first tension elastic bodies, and the two ends of each group of the first tension elastic bodies are respectively fixedly connected to the side surfaces of the two adjacent groups of sliding parts arranged on the same group of equilateral triangular frames.

[0009] The three-rod and nine-cable tensegrity structure has two different connection methods, which can achieve different deformation effects during compression. The first end of the rod of the three-rod and nine-cable tensegrity structure is connected to a vertex on the bottom surface of a regular tetrahedron in space, and the second end is connected to the diagonal vertex of the side rectangle of the regular tetrahedron, and each rod is spatially staggered and connected in sequence.

[0010] Each group of the first tension cell structure and each group of the second tension cell structure include: there are three groups of connecting rods, and both ends of each group of connecting rods are respectively hinged to the rod connecting members through the second connecting axis, the spatial position of each group of connecting rods is the same as the spatial position of the three-rod and nine-cable tensioned integral structure rods, and each group of connecting rods is spatially staggered and connected in sequence; there are three groups of the second tension elastic bodies, and both ends of each group of the second tension elastic bodies are respectively fixedly connected to the lower end of one group of connecting rods and the upper end of another adjacent group of connecting rods.

[0011] Each group of the first tensioned cellular structures and each group of the second tensioned cellular structures are hingedly connected through hinge holes at three corner positions of the equilateral triangle frame via the first connecting axis.

[0012] It can be known from the above technical solutions that compared with the prior art, the present invention discloses a triangular rotating rigid body structure with compression-torsion characteristics. Under the action of the three-rod and nine-cable tensegrity structure, when the structure is not subjected to external loads, the structure is subjected to the interaction of internal stresses and reaches equilibrium in a self-stable state; when subjected to external loads, the upper and lower surfaces of the cell structure will produce a torsional effect, and once the external load is removed, the structure will return to its initial state. A triangular rotating rigid body structure with compression-torsion characteristics has the advantages of adaptability, self-recovery, and indentation resistance characteristics. The present invention enriches the types of existing mechanical metamaterial cell structures by combining the tensegrity structure with the mechanical metamaterial structure, and opens up a new direction for the design, analysis, and application of tensegrity mechanical metamaterial structures.

[0013] Another object of the present invention is to provide a triangular rotating rigid body structure with compression-torsion characteristics, including a device body and the above-mentioned triangular rotating rigid body structure with compression-torsion characteristics connected thereto. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0015] Figure 1 The accompanying drawing is a schematic diagram of a first tension cell structure of a triangular rotating rigid body structure with compression-torsion characteristics provided by the present invention.

[0016] Figure 2 The accompanying drawing is a front view of a first tension cell structure of a triangular rotating rigid body structure with compression-torsion characteristics provided by the present invention.

[0017] Figure 3 The accompanying drawing is a top view of a first tension cell structure of a triangular rotation rigid body structure with compression-torsion characteristics provided by the present invention.

[0018] Figure 4 The accompanying drawing is a partial exploded schematic diagram of a first tension cell structure of a triangular rotating rigid body structure with compression-torsion characteristics provided by the present invention.

[0019] Figure 5 The accompanying drawing is a partial exploded schematic diagram of the connection part of the first tension cell structure degree of freedom constraint component of a triangular rotation rigid body structure with compression and torsion characteristics provided by the present invention.

[0020] Figure 6 The accompanying drawing is a schematic structural diagram of a first tension cell structure of a triangular rotating rigid body structure with compression-torsion characteristics provided by the present invention under a loaded state.

[0021] Figure 7 The accompanying drawings are structural diagrams of different connection modes of three-rod and nine-cable tensegrity structural members in a triangular rotating rigid body structure with compression-torsion characteristics provided by the present invention.

[0022] Figure 8 The accompanying drawing is a schematic diagram of a second tension cell structure of a triangular rotating rigid body structure with compression-torsion characteristics provided by the present invention.

[0023] Fig. 9 The accompanying drawing is a schematic structural diagram of a second tension cell structure of a triangular rotating rigid body structure with compression-torsion characteristics provided by the present invention under a loaded state.

[0024] Fig.10 The accompanying drawing is a schematic diagram of a triangular rotating rigid body structure with compression-torsion characteristics provided by the present invention.

[0025] Fig.11 The accompanying drawing is a top view of a triangular rotating rigid body structure with compression-torsion characteristics provided by the present invention.

[0026] Fig.12The accompanying drawing is a top view of the structure of a triangular rotating rigid body structure with compression-torsion characteristics provided by the present invention under a loaded state.

[0027] Among them, 1001-the first tensile cell structure; 1002-the second tensile cell structure; 300-the first connecting axis; 100-the degree of freedom constraint component; 101-the equilateral triangle frame; 102-the sliding component; 103-the rod connector; 104-the second connecting axis; 200-the three-rod tensile integral structure component; 201-the first tensile elastic body; 202-the second tensile elastic body; 203-the connecting rod. DETAILED DESCRIPTION

[0028] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0029] In the description of the present invention, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0030] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0032] In terms of structural design, existing mechanical metamaterials have a single cellular structure, and negative Poisson's ratio metamaterials are mostly integrated structures with low reusability. In addition, many designs to date have relied on the deformation or evolution of existing metamaterial structures, and it is impossible to systematically design geometric and topological shapes to obtain new metamaterial structures with negative Poisson's ratio effects.

[0033] In view of this, the embodiment of the present invention discloses a triangular rotating rigid body structure with compression torsion characteristics, see the attached Figure 1-12, including a first connecting shaft 300 and two tension cell structures with different connection modes based on a three-bar tension structure: a first tension cell structure 1001 and a second tension cell structure 1002; the first tension cell structure 1001 has three groups, and the second tension cell structure 1002 has three groups, thereby forming a six-cell structure of a triangular rotation rigid body structure with compression-torsion characteristics; the six-cell metamaterial structure is only one of the triangular rotation rigid body structures with compression-torsion characteristics, and the triangular rotation rigid body structure with compression-torsion characteristics includes other multi-cell structures of a negative Poisson's ratio metamaterial structure based on a three-bar tension structure and extended by the same connection mode as the first tension cell structure 1001 and the second tension cell structure 1002 in the six-cell metamaterial structure. Except for the different connection modes, the first tension cell structure 1001 and the second tension cell structure 1002 have the same components and connection modes of the components. Each group of the first tensile cell structure 1001 and each group of the second tensile cell structure 1002 include: a degree of freedom constraint component 100 and a three-rod tensile integral structure component 200; the degree of freedom constraint component 100 includes an equilateral triangle frame 101, a sliding component 102, a rod connector 103 and a second connecting shaft 104; the three-rod tensile integral structure component 200 includes a first tension elastic body 201, a second tension elastic body 202 and a connecting rod 203; there are two groups of the equilateral triangle frames 101, which are respectively placed at the upper and lower ends of the entire structure, and hinge holes are arranged at the outer edge positions of the three corners of the equilateral triangle frames 101. Three regular quadrangular prism structures inside the structure are arranged in a 120° circular array, and a hexagonal structure is arranged at the center of the structure and fixedly connected to the regular quadrangular prism structure. The function of the hinge holes is to enable the cell structures to be hingedly connected through the hinge holes. The regular quadrangular prism structure plays a guiding role, and the hexagonal structure in the middle plays a limiting role.

[0034] See attached Figure 4 , Attachment Figure 5In the embodiment of the present invention, each group of the first tension cell structure 1001 includes: there are six groups of sliding parts 102, which are respectively installed on the regular quadrangular prism structures of the two groups of the regular triangular frames 101, and the lower end of the sliding parts 102 is designed with a short axis; there are six groups of rod connectors 103, and the upper end surface of the structure is provided with a through hole, which cooperates with the short axis of the lower end of the sliding part 102 to achieve free rotation; the three groups of sliding parts 102 fixed on the regular quadrangular prism structure of the regular triangular frame 101 below and the three groups of sliding parts 102 fixed on the regular quadrangular prism structure of the regular triangular frame 101 above are arranged in opposite directions, and the three groups of rod connectors 103 rotatably connected to the three groups of sliding parts 102 below and the three groups of rod connectors 103 rotatably connected to the three groups of sliding parts 102 above are arranged in opposite directions; there are six groups of the second connecting shafts 104.

[0035] See attached Figure 4 Each group of the first tension cell structures 1001 includes: there are six groups of the first tension elastic bodies 201, and both ends of each group of the first tension elastic bodies 201 are respectively fixedly connected to the side surfaces of two adjacent groups of the sliding components 102 arranged on the same group of equilateral triangle frames 101.

[0036] See attached Figure 7 The three-rod and nine-cable tensegrity structure has two different connection methods, which can achieve different deformation effects during compression. The first end of the rod of the three-rod and nine-cable tensegrity structure is connected to a vertex on the bottom surface of a regular triangular prism in space, and the second end is connected to the diagonal vertex of the side rectangle of the regular triangular prism, and each rod is connected in sequence in a staggered manner in space.

[0037] In a preferred embodiment of the present invention, each group of the first tension cell structure 1001 includes: there are three groups of connecting rods 203, both ends of each group of connecting rods 203 are respectively hinged to the rod connector 103 through the second connecting axis 104, the spatial position of each group of connecting rods 203 is the same as the spatial position of the three-rod and nine-cable tensioned integral structure rods, and each group of connecting rods 203 are spatially staggered and connected in sequence.

[0038] Different deformation effects caused by different connection methods are: one is that after being loaded, the upper equilateral triangle frame 101 rotates clockwise relative to the lower equilateral triangle frame 101 in the top view direction; the other is that after being loaded, the upper equilateral triangle frame 101 rotates counterclockwise relative to the lower equilateral triangle frame 101 in the top view direction.

[0039] See attached Figure 5In the embodiments of the first tension cell structure 1001 and the second tension cell structure 1002 provided by the present invention, when working, the three groups of sliding components 102 fixed on the regular quadrangular prism structure of the equilateral triangular frame 101 below need to limit the sliding freedom. The rotation angle of the structure and the overall stiffness of the cell structure can be adjusted by adjusting the positions of the three groups of sliding components 102 on the regular quadrangular prism structure of the equilateral triangular frame 101 below. The connecting rod 203 is designed to be S-shaped in order to avoid interference and enable the cell structure to rotate at a larger angle.

[0040] In a preferred embodiment of the present invention, there are three groups of the second tension elastic bodies 202, and both ends of each group of the second tension elastic bodies 202 are fixedly connected to the lower end of one group of the connecting rods 203 and the upper end of another adjacent group of the connecting rods 203.

[0041] See attached Figure 1 and attached Figure 6 The working mode of the embodiment of the first tensioned cellular structure 1001 provided by the present invention is mainly that the cellular structure is under the action of the three-bar and nine-cable tensioned overall structure. When the structure is not subjected to external loads, the structure is subjected to the interaction of internal stresses and reaches equilibrium in a self-stable state; when subjected to external loads, the upper and lower surfaces will produce a torsional effect, and after the external loads are removed, the structure will return to its initial state.

[0042] See attached Figure 8 and attached Fig. 9 The working mode of the embodiment of the second tensioned cellular structure 1002 provided by the present invention is mainly that the cellular structure is under the action of the three-bar nine-cable tensioned overall structure. When the structure is not subjected to external loads, the structure is subjected to the interaction of internal stresses and reaches equilibrium in a self-stable state; when subjected to external loads, the upper and lower surfaces will produce a torsional effect, and the torsional direction is opposite to that of the embodiment of the first tensioned cellular structure. After the external load is removed, the structure will return to its initial state.

[0043] See attached Figure 10-12 Each group of the first tension cell structures 1001 and each group of the second tension cell structures 1002 are hinged at the hinge holes at the three corner positions of the equilateral triangle frame 101 through the first connecting axis 300, and when the structure is subjected to load, the deformation of the entire structure will show a negative Poisson's ratio effect.

[0044] The present invention provides a triangular rotating rigid body structure with compression-torsion characteristics, which has the advantages of adaptability, self-recovery, indentation resistance, etc.; the present invention enriches the types of existing mechanical metamaterial cell structures by combining the tensegrity structure with the mechanical metamaterial structure, and opens up a new direction for the design, analysis and application of tensegrity mechanical metamaterial structures; the present invention has important academic significance. The triangular rotating rigid body structure with compression-torsion characteristics provided by the present invention has a simple structure, is expected to be vigorously developed, and can realize its application value in many fields.

[0045] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification.

[0046] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A triangular rotating rigid body structure with compression-torsion characteristics, characterized in that: The invention relates to a tensile cellular structure comprising a first connecting axis (300) and two different connection modes based on a three-bar tensile structure: a first tensile cellular structure (1001) and a second tensile cellular structure (1002); the first tensile cellular structures (1001) have three groups in total, and the second tensile cellular structures (1002) have three groups in total; except for the different connection modes, the first tensile cellular structures (1001) and the second tensile cellular structures (1002) have the same components and connection modes of the components; each group of the first tensile cellular structures (1001) and each group of the second tensile cellular structures (1002) include: a degree of freedom constraint component (100) and a three-bar tensile integral structure component (200); The degree of freedom constraint assembly (100) comprises an equilateral triangle frame (101), a sliding component (102), a rod connecting component (103) and a second connecting shaft (104); the three-rod tensegrity structural assembly (200) comprises a first tension elastic body (201), a second tension elastic body (202) and a connecting rod (203); the equilateral triangle frame (101) has two groups, which are respectively arranged at the upper and lower ends of the entire structure; hinge holes are respectively arranged at the outer edge positions of the three corners of the equilateral triangle frame (101); three regular quadrangular prism structures are arranged in a 120° annular array inside the structure; a hexagonal structure is arranged at the center of the structure and is fixedly connected to the regular quadrangular prism structure; the sliding component (102) has six groups, which are respectively arranged at the upper and lower ends of the entire structure; The sliding components (102) are mounted on the regular quadrangular prism structures of the two groups of regular triangular frames (101), and the lower ends of the sliding components (102) are designed with short axes. There are six groups of rod connectors (103), and through holes are provided on the upper end surfaces of the structures to cooperate with the short axes at the lower ends of the sliding components (102) to achieve free rotation. The three groups of sliding components (102) fixed on the regular quadrangular prism structures of the lower regular triangular frames (101) and the three groups of sliding components (102) fixed on the regular quadrangular prism structures of the upper regular triangular frames (101) are arranged in opposite directions, and the three groups of rod connectors (103) rotatably connected to the three groups of sliding components (102) rotatably connected to the three groups of sliding components (102) on the upper sides are arranged in opposite directions. The rod connectors (103) are arranged in opposite directions; there are six groups of the second connecting shafts (104); there are six groups of the first tension elastic bodies (201); the two ends of each group of the first tension elastic bodies (201) are respectively fixedly connected to the side surfaces of two adjacent groups of sliding components (102) arranged on the same group of equilateral triangle frames (101); there are three groups of the connecting rods (203); the two ends of each group of the connecting rods (203) are respectively hinged to the rod connectors (103) through the second connecting shafts (104); the spatial position of each group of the connecting rods (203) is the same as the spatial position of the rods of the three-rod nine-cable tensegrity structure; and each group of the connecting rods (203) are spatially staggered and connected in sequence;There are three groups of the second tension elastic bodies (202), and the two ends of each group of the second tension elastic bodies (202) are respectively fixedly connected to the lower end of one group of the connecting rods (203) and the upper end of another adjacent group of the connecting rods (203).

2. A triangular rotating rigid body structure with compression-torsion characteristics according to claim 1, characterized in that: Each group of the first tensioned cellular structures (1001) and each group of the second tensioned cellular structures (1002) are hinged at hinge holes at three corner positions of the equilateral triangle frame (101) via the first connection axis (300), thereby forming a six-cell structure of a triangular rotational rigid body structure with compression and torsion characteristics.

3. The triangular rotating rigid body structure with compression-torsion characteristics according to claim 2, characterized in that: Other multi-cellular structures and devices including a triangular rotating rigid body structure with compression-torsion characteristics, which is composed of the first tensile cellular structure (1001) and the second tensile cellular structure (1002) and is extended in the same connection mode as the first tensile cellular structure (1001) and the second tensile cellular structure (1002) in the six-cellular metamaterial structure.

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