A bionic energy-absorbing tube with biological vertebral structure

Abstract

A bionic energy-absorbing tube with a biological spine structure belongs to the technical field of energy-absorbing structures. The central tube, inner circle tube assembly and outer circle tube assembly of the present invention are arranged in sequence from inside to outside and are located in a square tube; the tubes of the inner circle tube assembly and the outer circle tube assembly are arranged in a square shape, and the tubes, the central tube and the tubes of the inner circle tube assembly, the tubes of the outer circle tube assembly and the inner wall of the square tube are connected by ribs; the structure of the present invention is processed by CNC and 3D printing; the present invention adopts an optimal ratio of ribs and tube radius to maximize the improvement of collision resistance, and cleverly uses the deformation buffer layer between the central tube and the inner circle tube to avoid the occurrence of excessive rigidity, discontinuous deformation and unstable pressure bearing capacity caused by internal extrusion of the structure.

Description

Technical Field

[0001] The invention belongs to the technical field of energy absorbing structures, and in particular relates to a bionic energy absorbing tube with a biological spine structure. Background Art

[0002] Metal thin-walled structures have long been used as anti-collision devices because of their good load-bearing capacity and energy absorption characteristics. Existing thin-walled tubes deform greatly when impacted and have poor energy absorption effects. Summary of the invention

[0003] The purpose of the present invention is to solve the problem that the existing energy absorption structure has a relatively small energy absorption ratio, and to provide a bionic energy absorption tube with a biomimetic spinal structure having a large energy absorption ratio.

[0004] The present invention is inspired by the structural characteristics of biological vertebrae, which are connected by intervertebral discs, intervertebral joints, intervertebral ligaments and muscles between the vertebrae to form the continuity and stability of the spine.

[0005] The present invention discloses a bionic energy-absorbing tube with a biological spinal bone structure, which is composed of a square tube A and a tube core assembly B. Observing from the cross section of the energy-absorbing tube, the tube core assembly B is composed of a central tube 1, a pair of transverse rib plates 2, a pair of longitudinal rib plates 3, a rib plate group I 4, a rib plate group II 5, an inner circle circular tube assembly C and an outer circle circular tube assembly D, wherein the inner circle circular tube assembly C is composed of 16 circular tubes of the circular tube group I 6 and 16 rib plates of the rib plate group III 7, and the 16 circular tubes are arranged in a square and fixedly connected by 16 rib plates.

[0006] The outer ring circular tube assembly D is composed of 24 circular tubes of the circular tube group II 8 and 24 ribs of the rib plate group IV 9, and the 24 circular tubes are arranged in a square and fixedly connected by the 24 ribs.

[0007] The center tube 1, the inner ring tube assembly C and the outer ring tube assembly D are arranged sequentially from the inside to the outside. The center tube 1 is fixedly connected to the inner sides of the four tubes of the tube group Ⅰ6 in the inner ring tube assembly C through the two transverse ribs of the transverse rib plate pair 2 and the two longitudinal ribs of the longitudinal rib plate pair 3.

[0008] The outer sides of the 16 circular tubes of the inner circle circular tube assembly C are fixedly connected to the inner sides of the 20 circular tubes of the circular tube group II8 in the outer circle circular tube assembly D via the 20 ribs of the rib group II5.

[0009] The outer sides of the 24 circular tubes of the circular tube group II8 in the outer ring circular tube assembly D are fixed to the inner wall of the square tube A through the 28 ribs of the rib group I4.

[0010] The relationship between the radius r3 of the central tube 1 and the side length L of the outer wall of the square tube A is: The radius r1 of the 16 circular tubes in the circular tube group Ⅰ6 is the same as the radius r2 of the 24 circular tubes in the circular tube group Ⅱ8, and The distance between the centers of two adjacent circular tubes in the circular tube group Ⅰ6, l1, is the same as the distance between the centers of two adjacent circular tubes in the circular tube group Ⅱ8, l2, and The relationship between the center of the center tube 1 and the center of the tube in the tube group Ⅰ6, l3, and L is: The relationship between the distance l4 between the center of the circular tube in the circular tube group Ⅰ6 and the center of the circular tube in the circular tube group Ⅱ8 and L is: The center of the circular tube in the circular tube group II8 is the same as the longitudinal wall spacing l5 and the transverse wall spacing l6 of the square tube A, and The outer wall side length L of the square tube A is 40 to 90 mm.

[0011] The thickness t of the ribs in square tube A, center tube 1, each circular tube in circular tube group Ⅰ6, each circular tube in circular tube group Ⅱ8, transverse rib plate pair 2, longitudinal rib plate pair 3, rib plate group Ⅰ4, rib plate group Ⅱ5, rib plate group Ⅲ7, and rib plate group Ⅳ9 is the same, which is 0.4-1.0 mm.

[0012] The square tube A and the tube core assembly B are made of 7075 aluminum alloy.

[0013] The square tube A and the tube core assembly B are processed by CNC or 3D printing.

[0014] The beneficial effects of the present invention are as follows: the present invention adopts an optimal ratio of the rib plate to the radius of the circular tube to maximize the improvement of the impact resistance and energy absorption performance, and utilizes the gap between the center tube and the inner circle circular tube to form a deformation buffer layer. This design greatly reduces the peak load and can effectively avoid the occurrence of excessive rigidity, discontinuous deformation and unstable pressure bearing capacity caused by internal extrusion of the structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A schematic diagram of the structure of an energy-absorbing tube that mimics the structure of a biological spine;

[0016] Figure 2 A top view of an energy-absorbing tube that mimics a biological spine structure;

[0017] Figure 3 It is a structural schematic diagram of the inner ring tube component C;

[0018] Figure 4 It is a structural schematic diagram of the outer ring tube component D;

[0019] Figure 5 A 1 / 4 top view of the energy-absorbing tube that mimics the structure of a biological spine;

[0020] Figure 6 It is a schematic diagram of various ratios of the tube radius and the rib length;

[0021] Figure 7 for Figure 6 Load displacement curves of thin-walled circular tubes under various mix ratios;

[0022] Figure 8 The figure is a comparison diagram of radial load displacement curves of the present invention and ordinary pipes;

[0023] Fig. 9 This is a comparison diagram of the specific energy absorption of the present invention and the ordinary tube;

[0024] Among them: A. Square tube B. Tube core assembly C. Inner ring round tube assembly D. Outer ring round tube assembly 1. Center tube 2. Horizontal rib plate pair 3. Longitudinal rib plate pair 4. Rib plate group I 5. Rib plate group II 6. Round tube group I 7. Rib plate group III 8. Round tube group II 9. Rib plate group IV. DETAILED DESCRIPTION

[0025] The present invention is described below with reference to the accompanying drawings.

[0026] like Figure 1 and Figure 2 As shown, the bionic energy-absorbing tube with a biological spinal bone structure of the present invention is composed of a square tube A and a tube core assembly B. Observing from the cross section of the energy-absorbing tube, the tube core assembly B is composed of a central tube 1, a pair of transverse rib plates 2, a pair of longitudinal rib plates 3, a rib plate group I 4, a rib plate group II 5, an inner circle circular tube assembly C and an outer circle circular tube assembly D.

[0027] like Figure 3 As shown, the inner circle circular tube assembly C is composed of 16 circular tubes of the circular tube group I6 and 16 ribs of the rib plate group III7, and the 16 circular tubes are arranged in a square and fixedly connected by the 16 ribs.

[0028] like Figure 4 As shown, the outer ring circular tube assembly D is composed of 24 circular tubes of the circular tube group II 8 and 24 ribs of the rib plate group IV 9, and the 24 circular tubes are arranged in a square and fixedly connected by the 24 ribs.

[0029] like Figure 2 As shown, the center tube 1, the inner ring circular tube assembly C and the outer ring circular tube assembly D are arranged in sequence from the inside to the outside, and the center tube 1 is fixedly connected to the inner sides of the four circular tubes of the circular tube group Ⅰ6 in the inner ring circular tube assembly C through the two transverse ribs of the transverse rib plate pair 2 and the two longitudinal ribs of the longitudinal rib plate pair 3.

[0030] The outer sides of the 16 circular tubes of the inner circle circular tube assembly C are fixedly connected to the inner sides of the 20 circular tubes of the circular tube group II8 in the outer circle circular tube assembly D via the 20 ribs of the rib group II5.

[0031] The outer sides of the 24 circular tubes of the circular tube group II8 in the outer ring circular tube assembly D are fixed to the inner wall of the square tube A through the 28 ribs of the rib group I4.

[0032] like Figure 5 As shown, the relationship between the radius r3 of the central tube 1 and the side length L of the outer wall of the square tube A is: The radius r1 of the 16 circular tubes in the circular tube group Ⅰ6 is the same as the radius r2 of the 24 circular tubes in the circular tube group Ⅱ8, and The distance between the centers of two adjacent circular tubes in the circular tube group Ⅰ6, l1, is the same as the distance between the centers of two adjacent circular tubes in the circular tube group Ⅱ8, l2, and The relationship between the center of the center tube 1 and the center of the tube in the tube group Ⅰ6, l3, and L is: The relationship between the distance l4 between the center of the circular tube in the circular tube group Ⅰ6 and the center of the circular tube in the circular tube group Ⅱ8 and L is: The center of the circular tube in the circular tube group II8 is the same as the longitudinal wall spacing l5 and the transverse wall spacing l6 of the square tube A, and The outer wall side length L of the square tube A is 40 to 90 mm.

[0033] The thickness t of the ribs in square tube A, center tube 1, each circular tube in circular tube group Ⅰ6, each circular tube in circular tube group Ⅱ8, transverse rib plate pair 2, longitudinal rib plate pair 3, rib plate group Ⅰ4, rib plate group Ⅱ5, rib plate group Ⅲ7, and rib plate group Ⅳ9 is the same, which is 0.4-1.0 mm.

[0034] The square tube A and the tube core assembly B are made of 7075 aluminum alloy.

[0035] The square tube A and the tube core assembly B are processed by CNC or 3D printing.

[0036] The process of determining the proportional relationship between the tube radius and the rib length in the present invention is as follows:

[0037] The material of the tube wall is 7075 aluminum alloy, which has the advantages of high strength, good mechanical properties and easy processing. The density of the material is 2.73×10 -6 kg / mm 3 , elastic modulus is 70Gpa, Poisson's ratio is 0.31, yield strength σ y =503MPa, ultimate stress σ u =572MPa. In ABAQUS, a rigid plate with an initial velocity of v=10m / s was used to collide with the bionic tube. In the analysis and calculation process, the tube wall of square tube A adopted an automatic contact algorithm, so that the deformation generated by the tube wall during compression contacted and rubbed each other, and the static friction coefficient between the compressed tube walls was 0.3.

[0038] Figure 6 This is a schematic diagram of the size ratio of a single round tube and rib plate length. Figure 7 The load-displacement relationship of 14 different sizes of pipes under axial impact is shown. As the length of the rib increases, the initial peak load (MCF) gradually increases, but within the compression displacement range of 0 to 20.0 mm, l 14 r6 shows the best pressure bearing capacity.20 r0 shows medium pressure bearing capacity, MCF l20r0 50.08KN, close to MCF l9r11 , while MCF l14r16 The maximum is 56.65KN, which is 1.13 times that of ordinary tubes. This shows that the existence of the central circular tube can change the pressure bearing capacity of the tube, and when the radius r of the circular tube is less than 11.0mm, the pressure bearing capacity of the thin-walled tube can be greatly improved. The load displacement variation trend of the 14 types of tubes shows that the length of the rib plate is 11.0mm as the limit. When the rib plate length is ≤11.0mm, the load of the bionic tube fluctuates violently with the increase of compression displacement, indicating that the pressure bearing capacity of this part of the tube is unstable; while the pressure bearing capacity of the bionic tube with a support rib length of ≤11.0mm is higher and more stable.

[0039] Figure 1 and Figure 2 The bionic energy-absorbing tube of the present invention is designed in combination with the factor of stable deformation after determining the bionic tube with the optimal crash resistance ratio of a single bionic unit.

[0040] Table 1 Comparison of crash resistance performance of energy absorbing tubes

[0041]

[0042]

[0043] As shown in Table 1, when the bionic tube of the present invention is impacted, the average load it receives is 141.37 KN, which is 11.54 times that of an ordinary tube of the same thickness and 1.56 times that of an ordinary tube of the same mass. The specific energy absorption of the bionic energy-absorbing tube of the present invention is 102.26 kJ, which is 3.65 times that of an ordinary tube of the same thickness and 1.56 times that of an ordinary tube of the same mass. Therefore, during a collision, the energy absorption effect of the bionic energy-absorbing tube of the present invention is significantly improved.

Claims

1. A bionic energy absorbing tube with a biological vertebral structure, comprising a square tube (A) and a tube core assembly (B). Observing from the cross section of the energy absorbing tube, the tube core assembly (B) comprises a central tube (1), a pair of transverse ribs (2), a pair of longitudinal ribs (3), a rib group I (4), a rib group II (5), an inner circle circular tube assembly (C) and an outer circle circular tube assembly (D), wherein the inner circle circular tube assembly (C) comprises 16 circular tubes of the circular tube group I (6) and 16 ribs of the rib group III (7), and the 16 circular tubes are arranged in a square and fixedly connected by the 16 ribs; the outer circle circular tube assembly (D) comprises 24 circular tubes of the circular tube group II (8) and 24 ribs of the rib group IV (9), and the 24 circular tubes are arranged in a square and fixedly connected by the 24 ribs; the central tube (1), the inner circle circular tube assembly (C) and the outer ring round tube assembly (D) are arranged sequentially from the inside to the outside, the center tube (1) is fixedly connected to the inner sides of the four round tubes of the round tube group I (6) in the inner ring round tube assembly (C) through the two transverse ribs of the transverse rib plate pair (2) and the two longitudinal ribs of the longitudinal rib plate pair (3); the outer sides of the 16 round tubes of the inner ring round tube assembly (C) are fixedly connected to the inner sides of the 20 round tubes of the round tube group II (8) in the outer ring round tube assembly (D) through the 20 ribs of the rib plate group II (5); the outer sides of the 24 round tubes of the round tube group II (8) in the outer ring round tube assembly (D) are fixedly connected to the inner wall of the square tube (A) through the 28 ribs of the rib plate group I (4); the material of the square tube (A) and the tube core assembly (B) is 7075 aluminum alloy, and the square tube (A) and the tube core assembly (B) are processed by CNC or 3D printing; it is characterized in that: The relationship between the radius r3 of the central tube (1) and the side length L of the outer wall of the square tube (A) is: The radius r1 of the 16 circular tubes in the circular tube group Ⅰ (6) is the same as the radius r2 of the 24 circular tubes in the circular tube group Ⅱ (8), and The distance between the centers of two adjacent circular tubes in the circular tube group I (6) is the same as the distance between the centers of two adjacent circular tubes in the circular tube group II (8), and The relationship between the center of the central tube (1) and the center of the tube in the tube group I (6) and L is: The relationship between the distance l4 between the center of the circular tube in the circular tube group Ⅰ (6) and the center of the circular tube in the circular tube group Ⅱ (8) and L is: The center of the circular tube in the circular tube group II (8) is the same as the longitudinal wall spacing l5 and the transverse wall spacing l6 of the square tube (A), and The side length L of the outer wall of the square tube (A) is 40 to 90 mm; the thickness t of the ribs in the square tube (A), the center tube (1), each circular tube in the circular tube group I (6), each circular tube in the circular tube group II (8), the transverse rib plate pair (2), the longitudinal rib plate pair (3), the rib plate group I (4), the rib plate group II (5), the rib plate group III (7), and the rib plate group IV (9) is the same, which is 0.4 to 1.0 mm.

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