Novel energy absorption box based on zero-Poisson-ratio pressure-torsion metamaterial filling

Abstract

The invention discloses a novel energy absorption box based on zero-Poisson-ratio pressure-torsion metamaterial filling, and relates to the technical field of mechanical metamaterials. The energy absorption box comprises a cylindrical thin-wall shell, a front end plate fixedly connected with the front portion of the cylindrical thin-wall shell, a rear end plate arranged on the rear portion of the cylindrical thin-wall shell, and a 3D accordion type zero-Poisson-ratio compression-torsion metamaterial energy absorption filling body installed in the cylindrical thin-wall shell. The novel energy absorption box based on zero-Poisson-ratio pressure-torsion metamaterial filling has excellent energy absorption capacity and good energy absorption stability; the design of structural parameters can be correspondingly adjusted according to actual working condition requirements; and the method has rich parameter design diversity.

Description

Technical Field

[0001] The present invention relates to the technical field of mechanical metamaterials, and in particular to a novel energy absorbing box filled with zero Poisson's ratio compression-torsion metamaterial. Background Art

[0002] Automobile safety plays a vital role in automobile research and development and is related to the safety of people's lives and property. The energy absorption box is a passive safety device widely used in the field of automobile safety. It can absorb impact energy in a car collision accident to protect the safety of personnel and the integrity and stability of the main structure of the car.

[0003] Mechanical metamaterials refer to a type of structure and material that is artificially designed with specific microstructure units arranged periodically in an elastic medium. It can obtain extraordinary physical properties, such as negative Poisson's ratio, higher shear modulus, larger indentation resistance, etc. Due to its unique properties and extraordinary performance, metamaterials have attracted much attention from the scientific community and have broad prospects for engineering applications.

[0004] Therefore, in order to solve the above problems, this paper proposes a new energy absorption box filled with zero Poisson's ratio compression-torsion metamaterial. Summary of the invention

[0005] The purpose of the present invention is to propose a new energy absorption box filled with zero Poisson's ratio compression-torsion metamaterial, by combining mechanical metamaterial with the energy absorption box, utilizing its compression-torsion and zero Poisson's ratio characteristics to improve the crashworthiness of the energy absorption box and obtain good energy absorption capacity.

[0006] In order to achieve the above technical effects, the present invention is implemented through the following technical solutions: a new energy absorbing box based on zero Poisson's ratio compression-torsion metamaterial filling, characterized in that it includes a cylindrical thin-walled shell, a front end plate fixedly connected to the front of the cylindrical thin-walled shell, a rear end plate arranged at the rear of the cylindrical thin-walled shell, and a 3D accordion-shaped zero Poisson's ratio compression-torsion metamaterial energy absorbing filling body installed inside the cylindrical thin-walled shell;

[0007] The 3D accordion-type zero Poisson's ratio compression-torsion metamaterial energy absorbing filler includes at least one 3D accordion-type zero Poisson's ratio unit cell and at least one compression-torsion cell on the circumferential outer side. The axis of the cylindrical thin-walled shell is parallel to the axis of the 3D accordion-type zero Poisson's ratio compression-torsion metamaterial energy absorbing filler.

[0008] Furthermore, the 3D accordion-type zero Poisson's ratio unit cell includes at least two cosine function connecting rods; the axis of the 3D accordion-type zero Poisson's ratio unit cell is parallel to the axis of the cosine function connecting rod.

[0009] Furthermore, axially adjacent 3D accordion-shaped zero Poisson's ratio unit cells are connected by a plurality of horizontal connecting rods.

[0010] Furthermore, each 3D accordion-shaped zero Poisson's ratio compression-torsion metamaterial energy-absorbing filling body is formed by axially stacking a plurality of 3D accordion-shaped zero Poisson's ratio unit cells, and each 3D accordion-shaped zero Poisson's ratio unit cell is connected by a plurality of cosine function connecting rods and a plurality of horizontal connecting rods.

[0011] Furthermore, the cylindrical thin-walled outer shell has at least one circumferentially surrounding crush inducing groove.

[0012] The beneficial effects of the present invention are:

[0013] The metamaterial used in the energy absorbing filling body of the energy absorbing box of the present invention has multiple cosine function type connecting rods compared with the traditional energy absorbing box filling body; when the energy absorbing box is subjected to impact load, the cosine function type connecting rods are bent and folded, and the energy absorbing structure rotates around the axial direction; the kinetic energy during the impact is converted into internal energy, so that the impact energy is fully absorbed; the energy absorption effect of this 3D accordion type zero Poisson compression-torsion ratio metamaterial structure is significantly better than the thin-walled tube structure inside the traditional energy absorbing box; the energy absorbing box of the present invention installs the front and rear end panels between the automobile frame and the bumper by bolts, and there is no need to change the existing structure of the vehicle, and it can be directly replaced and installed, which has broad prospects in engineering applications;

[0014] The energy absorption box of the present invention adopts a metamaterial with a zero Poisson's ratio as an energy absorption filler. When axial crushing occurs, the structure will not bulge outward or collapse inward; it ensures that the cells of each layer can fold and collapse after bending and deformation during a collision, and act on the cells of the next layer; the compression and torsion of the cells can further deform the energy absorption structure, so that the cell connecting rods of the metamaterial are completely folded; this sequential collapse deformation mode can effectively reduce the oscillation amplitude of the collision force, and make all the cell structures completely crushed; in addition, the bending deformation of the cosine function type connecting rod can effectively reduce the initial peak stress, reduce the acceleration during the collision, and reduce the damage to personnel and vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0016] Figure 1 It is a schematic diagram of the three-dimensional structure of a novel energy absorption box filled with zero Poisson compression-torsion ratio metamaterial of the present invention;

[0017] Figure 2 It is a schematic diagram of the 3D accordion-type zero Poisson's ratio compression-torsion metamaterial energy-absorbing filling body of the present invention;

[0018] Figure 3It is a schematic diagram of the three-dimensional structure of the 3D accordion-type zero Poisson's ratio unit cell of the present invention;

[0019] Figure 4 This is a schematic diagram of the compression and twisting cell of the present invention;

[0020] Figure 5 This is a schematic diagram of a traditional 3D concave hexagonal negative Poisson's ratio structure;

[0021] Figure 6 It is a comparison diagram of stress-strain curves of the new energy absorption box of the present invention and the energy absorption box filled with a traditional 3D concave hexagonal negative Poisson's ratio structure.

[0022] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0023] 1. Front end plate; 2. Cylindrical thin-walled shell; 3. Rear end plate; 4. 3D accordion-type zero Poisson's ratio compression-torsion metamaterial energy-absorbing filler; 41. Cosine function connecting rod; 42. Horizontal connecting rod. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] Example 1

[0026] like Figure 1 As shown, the novel energy absorbing box filled with zero Poisson's ratio compression-torsion metamaterial of the present invention comprises a cylindrical thin-walled shell 2, a front end plate 1 fixedly connected to the front end of the cylindrical thin-walled shell 2, and a rear end plate 3 fixedly connected to the rear end of the cylindrical thin-walled shell 2, and a 3D accordion-shaped zero Poisson's ratio compression-torsion metamaterial energy absorbing body 4 is provided in the cavity formed by the cylindrical thin-walled shell 2 and the front end plate 1 and the rear end plate 3.

[0027] like Figure 2 The zero Poisson's ratio compression-torsion metamaterial energy absorbing filler 4 shown needs to include at least one unit cell (such as Figure 3 ), the axis of the cylindrical thin-walled shell 2 is parallel to the axis of the energy-absorbing filling body structure 4.

[0028] In order to make the energy absorbing box twist under the compressive load, a compression-torsion cell (such as Figure 4 The energy absorbing box is twisted during the crushing process, and the internal zero Poisson's ratio compression-torsion metamaterial energy absorbing filler 4 and the cylindrical thin-walled shell 2 can achieve a greater degree of deformation, thereby improving the energy absorption capacity of the energy absorbing box.

[0029] The lower end of the cylindrical thin-walled shell 2 is fixedly connected to the rear end plate 3 by welding. The rear end plate 3 of the energy absorption box is connected to the front longitudinal beam of the frame by bolts, and the front end plate 1 is connected to the anti-collision beam of the vehicle by bolts to complete the installation of the energy absorption box on the vehicle.

[0030] like Figure 2 , 3 As shown in 4, the zero Poisson's ratio compression-torsion metamaterial energy-absorbing filler is obtained by arranging the compression-torsion type cells on the outside of the energy-absorbing filler with the single 3D accordion type zero Poisson's ratio unit cell array. The single 3D accordion type zero Poisson's ratio unit cell is composed of a horizontal connecting rod 42 and a cosine function connecting rod 41. When crushed, the cosine function connecting rod 41 bends and folds, and the compression-torsion cell undergoes axial twisting.

[0031] like Figure 3 The 3D accordion-type zero Poisson's ratio unit cell is composed of the rotation and translation of the horizontal link 42 and the cosine function link 41 in space, wherein the tensile thickness b of the cell can affect the energy absorption capacity of the structure.

[0032] like Figure 4 , showing the front view of the cell structure of the compressed and twisted cell.

[0033] like Figure 6 , based on finite element simulation, the new energy absorption box and the traditional 3D concave hexagonal negative Poisson's ratio structure ( Figure 5 ) shows a stress-strain curve comparison diagram of the energy absorption box filled with the present invention, which shows that the present invention has obvious advantages in energy absorption.

[0034] The specific implementation modes of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above implementation modes, and various changes can be made within the knowledge scope of ordinary technicians in this field without departing from the purpose of the present invention.

Claims

1. A new energy absorption box filled with zero Poisson's ratio compression-torsion metamaterial, characterized in that: The invention comprises a cylindrical thin-walled shell, a front end plate fixedly connected to the front of the cylindrical thin-walled shell, a rear end plate arranged at the rear of the cylindrical thin-walled shell, and a 3D accordion-shaped zero Poisson's ratio compression-torsion metamaterial energy-absorbing filling body installed inside the cylindrical thin-walled shell; The 3D accordion-type zero Poisson's ratio compression-torsion metamaterial energy absorbing filler includes at least one 3D accordion-type zero Poisson's ratio unit cell and at least one compression-torsion cell on the circumferential outer side. The axis of the cylindrical thin-walled shell is parallel to the axis of the 3D accordion-type zero Poisson's ratio compression-torsion metamaterial energy absorbing filler.

2. According to claim 1, a novel energy absorption box filled with zero Poisson's ratio compression-torsion metamaterial is characterized in that: The 3D accordion-type zero Poisson's ratio unit cell includes at least two cosine function connecting rods, wherein the contour of the cosine function connecting rod is intercepted from the function graph of a complete half cycle of the cosine function on one side of the X-axis, the cosine function connecting rod is connected to the inner sides of the two horizontal connecting rods, and each layer of horizontal connecting rods is connected to form an integral structure through the cosine function connecting rod; the axis of the 3D accordion-type zero Poisson's ratio unit cell is parallel to the axis of the cosine function connecting rod.

3. According to claim 1, a novel energy absorption box filled with zero Poisson's ratio compression-torsion metamaterial is characterized in that: Axially adjacent 3D accordion-shaped zero Poisson's ratio unit cells are connected by multiple horizontal connecting rods.

4. According to claim 1, a novel energy absorption box filled with zero Poisson's ratio compression-torsion metamaterial is characterized in that: Each 3D accordion-shaped zero Poisson's ratio compression-torsion metamaterial energy-absorbing filling body is composed of multiple 3D accordion-shaped zero Poisson's ratio unit cells stacked axially, and each 3D accordion-shaped zero Poisson's ratio unit cell is connected by multiple cosine function connecting rods and multiple horizontal connecting rods.

5. According to claim 1, a novel energy absorption box filled with zero Poisson's ratio compression-torsion metamaterial is characterized in that: The cylindrical thin-walled shell has at least one circumferentially surrounding crush inducing groove.

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