A biomimetic passive energy absorption device for automobiles based on nickel-titanium alloy

Abstract

The application discloses a kind of bionic passive energy-absorbing devices of automobile based on nickel-titanium alloy, it is related to the technical field of passive safety of automobile, including crash beam main body, two energy-absorbing boxes are fixedly arranged in crash beam main body side, bionic energy-absorbing inner core is filled in energy-absorbing box, the material of crash beam main body, energy-absorbing box, bionic energy-absorbing inner core is nickel-titanium alloy, and is integrally printed into shape by additive manufacturing mode respectively.The differentiated bionic dot matrix structure of the crash beam main body and the energy-absorbing box designed in the application forms a synergistic energy-absorbing system, achieving full-process optimization of collision load gradient buffering-energy layered dissipation-deformation precise control.The crash beam main body first buffers the instantaneous load in the initial stage of collision, reduces the peak load, and creates stable conditions for subsequent energy absorption of the energy-absorbing box.The crash beam main body dissipates collision energy, and the remaining energy is further layered dissipated by the bionic dot matrix structure of the energy-absorbing box.

Description

TECHNICAL FIELD

[0001] The application relates to the field of automobile passive safety technology, and particularly relates to a bionic automobile passive energy-absorbing device based on a nickel-titanium alloy. BACKGROUND

[0002] In an automobile passive safety system, a crash beam and an energy-absorbing box are core protection components, but the prior art cannot meet the requirements of safety and light weight, and defects such as insufficient material performance and single structure design are common. The energy-absorbing box mainly adopts traditional materials such as steel and aluminum alloy, the steel material has the defects of large density and low energy-absorbing efficiency, the aluminum alloy has the defects of poor impact toughness and obvious low-temperature performance attenuation, the crash beam is mostly made of steel or ordinary aluminum alloy, the steel material has the defects of large weight and weak corrosion resistance, and the aluminum alloy has the defect of insufficient impact load capacity, and all of them cannot meet the requirements of light weight and high energy-absorbing efficiency.

[0003] In terms of structure design, the energy-absorbing box is mainly in a single-pipe structure, the energy-absorbing path is fixed, and the energy-absorbing efficiency is suddenly reduced when instability deformation occurs in the face of non-frontal collision; the crash beam is mostly in a regular shape such as a flat type and a simple arc shape, the load receiving area is limited, stress concentration is prone to occur during collision, and the load cannot be evenly dispersed. Both types of components lack the optimized design of high-efficiency impact resistance mechanism and have poor multi-working-condition adaptability.

[0004] Therefore, the bionic automobile passive energy-absorbing device based on the nickel-titanium alloy is provided to solve the above problems. SUMMARY

[0005] To achieve the above object, the application provides the following technical scheme: a bionic automobile passive energy-absorbing device based on a nickel-titanium alloy, comprising a crash beam main body, two energy-absorbing boxes are fixedly arranged on one side of the crash beam main body, and a bionic energy-absorbing inner core is filled in each energy-absorbing box; the crash beam main body, the energy-absorbing boxes and the bionic energy-absorbing inner core are made of a nickel-titanium alloy and are integrally printed by additive manufacturing.

[0006] Preferably, the bionic energy-absorbing inner core is in a structure similar to a woodpecker's beak negative Poisson's ratio structure or a structure similar to a radiolarian.

[0007] Preferably, the energy-absorbing box near the driver side is filled with the woodpecker's beak negative Poisson's ratio structure, and the energy-absorbing box near the passenger side is filled with the structure similar to a radiolarian.

[0008] Preferably, the crash beam main body is in a structure similar to a beetle's sheath wing, the beetle's sheath wing of a magic iron yao beetle is taken as a bionic prototype, the cross-sectional surface of the magic iron yao beetle's sheath wing is selected for fine topological structure design, the structure similar to the beetle's sheath wing is constructed by micro-imaging and three-dimensional reconstruction technology, and the specific steps are as follows:

[0009] Step 1: Use a microtome to cut a cross section of the elytra of the Elytra fasciata, ensuring that the section thickness is uniform and the cut surface is flat and burr-free. Fix half of the section to the electron microscope sample stage with conductive adhesive, and then perform gold sputtering to enhance the conductivity of the sample. Use a scanning electron microscope to observe, select an area with a clear field of view that contains the complete outline of the elytra, and take a picture at a magnification of 1 mm to obtain an electron microscope image.

[0010] Step 2: Import the electron microscope image into Photoshop, adjust the brightness and contrast to make the outline of the elytra clearly demarcate from the background, remove noise, select the outer outline and internal structure edge of the elytra, generate vector paths and export as DXF format.

[0011] Step 3: Create a new generative shape design part file in CATIA. Enter the sketch editor, select the XY plane as the drawing plane, import the DXF format file, and use the constraint tool to align the image scale with the CATIA coordinate system. A 1mm line segment in the image corresponds to a length of 1000mm in CATIA. Then, select the contour command and click on key points along the outer contour of the elytra in the image to generate a continuous spline curve. Smooth the spline curve and use the connect command to merge the start and end points. Next, draw the internal staggered support structure unit. Use the same contour tool to draw the support structure and edge details inside the elytra. For symmetrical structures, draw one half first, and then use the mirror command to generate the other half. Use the topology offset command to process the obtained planar sketch to generate the overall anti-collision beam structure. Then, in the middle part of the anti-collision beam structure, merge the reinforcing ribs through Boolean operations to finally obtain the main body of the anti-collision beam.

[0012] Preferably, the reinforcing rib is provided with multiple elliptical through holes.

[0013] As a preferred embodiment, the specific steps for constructing a woodpecker-like beak structure with a negative Poisson's ratio are as follows:

[0014] Step 1: Construct two mutually perpendicular circular rings using 3D modeling software;

[0015] Step 2: On one of the rings, four wavy support structures, A, B, C, and D, are uniformly constructed along the circumference. On the other ring, four wavy support structures, E, F, G, and H, are also uniformly constructed along the circumference. The wavy support structures are generated by scanning a path using a circular outline and a sine function. The ends of A, B, E, and F that are away from the ring are located in the same plane, and the ends of C, D, G, and H that are away from the ring are located in the same plane.

[0016] Step 3: Construct ring 2 through A, E, C, and G, and ring 2 through B, F, D, and H to obtain the woodpecker beak negative Poisson's ratio structural unit;

[0017] Step 4: Linearly array the woodpecker beak negative Poisson's ratio structural units along the X-axis, Y-axis and Z-axis respectively. Multiple woodpecker beak negative Poisson's ratio structural units distributed in a three-dimensional grid array are combined to form a woodpecker beak negative Poisson's ratio structure.

[0018] As a preferred embodiment, the specific steps for constructing the radiolarian-like structure are as follows:

[0019] Step 1: Open the electron microscope image of the radiolarian in Photoshop. Adjust the contrast and noise reduction to make the spines and mesh outlines on the surface clearer. Then, use the quick selection tool to select a unit outline, convert it to a vector path, and export it as a DXF format.

[0020] Step 2: Restore the surface feature elements of the radiolarian in CATIA. Create a new generative shape design part file in CATIA, enter the sketch editor, select the XY plane as the drawing plane, import the DXF format file, use the constraint tool to align the image scale with the CATIA coordinate system, use the contour tool to trace the inner and outer contours of the star-shaped feature along the edge of the image to obtain a hexagonal sketch; input the sphere radius r=5mm to generate a complete sphere as the projection target, then select the previously drawn sketch, select the spherical projection command, set the projection distance to 10mm, the number to 2 layers, copy the projected feature along the circumference of the sphere, select the center of the sphere as the array center axis, input the array number to 12, and the angle interval to 30° to obtain the radiolarian structural element;

[0021] Step 3: Linearly array the radiolarian structural units along the X-axis, Y-axis and Z-axis respectively. Multiple radiolarian structural units distributed in a three-dimensional grid array are combined to form a radiolarian-like structure.

[0022] Preferably, the main body of the crash beam has two sets of bolt holes on one side, and each set of bolt holes is connected to an energy-absorbing box by fastening bolts. The side of the energy-absorbing box away from the main body of the crash beam has a limit hole.

[0023] The present invention has the following beneficial effects:

[0024] The anti-collision beam body and the energy-absorbing box designed in this invention form a synergistic energy absorption system with differentiated biomimetic lattice structures, achieving full-process optimization of collision load gradient buffering, energy stratified dissipation, and precise deformation control. Load gradient buffering: The anti-collision beam body first buffers the instantaneous load at the initial stage of the collision, reducing the peak load and creating stable conditions for subsequent energy absorption by the energy-absorbing box. Energy stratified dissipation: The anti-collision beam body dissipates the collision energy, and the remaining energy is further stratified and dissipated by the biomimetic lattice structure of the energy-absorbing box. Precise deformation control: The load-bearing structures of the anti-collision beam body and the energy-absorbing box work together to precisely control the structural deformation boundary, while ensuring the integrity of the vehicle's longitudinal beams, preserving sufficient survival space for occupants. The performance advantages of this synergistic system far exceed the traditional combination of anti-collision beam + energy-absorbing box, achieving a system-level performance improvement of 1+1>2.

[0025] The anti-collision beam and energy-absorbing box of this invention have excellent energy absorption capacity and shape self-restoration capability, and can be reused, reducing automobile maintenance costs. This device is manufactured using additive manufacturing technology with nickel-titanium alloy as the material. Utilizing the shape memory properties of nickel-titanium alloy, used automotive passive energy-absorbing devices can be disassembled and heated to restore their original shape for reuse, reducing automobile maintenance costs and solving the problem that traditional anti-collision beams and energy-absorbing boxes are easily broken upon impact and cannot be reused. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0027] Figure 2 This is a schematic diagram of the design process of the anti-collision beam body in this invention;

[0028] Figure 3 This is a schematic diagram of the main structure of the anti-collision beam in this invention;

[0029] Figure 4 This is a schematic diagram of the reinforcing rib in this invention;

[0030] Figure 5 This is a schematic diagram of the internal filling of the energy-absorbing box in this invention;

[0031] Figure 6 This is a schematic diagram illustrating the design process of the woodpecker beak-inspired negative Poisson's ratio structure in this invention.

[0032] Figure 7 This is a schematic diagram illustrating the design process of the radiolarian-like structure in this invention.

[0033] In the diagram: 1. Main body of the anti-collision beam; 2. Reinforcing ribs; 3. Fastening bolts; 4. Energy-absorbing box; 5. Limiting hole; 6. Bolt hole; 7. Bionic energy-absorbing inner core. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0036] Embodiments of the present invention

[0037] like Figures 1 to 5 As shown, a biomimetic passive energy-absorbing device for automobiles based on nickel-titanium alloy includes a crash beam body 1. Two sets of bolt holes 6 are provided on one side of the crash beam body 1. Each set of bolt holes 6 is connected to an energy-absorbing box 4 via fastening bolts 3. Limiting holes 5 are provided on the side of the energy-absorbing box 4 away from the crash beam body 1. The function of the limiting holes 5 is to accurately position the energy-absorbing box 4 and limit its initial position, ensuring that the crushing deformation occurs orderly along the designed path during a collision, avoiding off-center loading and premature failure. The energy-absorbing box 4 is filled with a biomimetic energy-absorbing core 7. The crash beam body 1, fastening bolts 3, energy-absorbing box 4, and biomimetic energy-absorbing core 7 are all made of nickel-titanium alloy and are integrally printed using additive manufacturing.

[0038] The biomimetic energy-absorbing core 7 is either a woodpecker beak-inspired negative Poisson's ratio structure or a radiolarian-inspired structure. Both structures offer excellent impact resistance and energy absorption. The use of nickel-titanium alloy materials and additive manufacturing technology simplifies the fabrication of complex energy-absorbing structures and incorporates the material's shape memory effect. The energy-absorbing box 4 near the driver's side is filled with a woodpecker beak-inspired negative Poisson's ratio structure, while the energy-absorbing box 4 near the passenger's side is filled with a radiolarian-inspired structure.

[0039] like Figures 1 to 4 As shown, the main body 1 of the crash beam is a beetle elytra-like structure, modeled after the elytra of the beetle *Gnaphalium affine*. This beetle elytra, with its unique microscopic hierarchical structure and topological morphology, exhibits extraordinary load-bearing capacity, capable of withstanding a maximum pressure of 149 N, approximately 39,000 times its own weight. This ultra-high load-bearing ratio far exceeds that of most lightweight biological structures in nature. A refined topological structure design was performed on the cross-sectional surface of the *Gnaphalium affine* elytra. The beetle elytra-like structure was constructed using microscopic imaging and 3D reconstruction technology. The specific steps are as follows:

[0040] Step 1, press the Demon Iron Armor Elytra... Figure 2At position AA, a cross-section of the elytra was cut using a microtome, ensuring uniform slice thickness and a smooth, burr-free cut surface. Half of the slice was fixed to the electron microscope stage with conductive adhesive, followed by gold sputtering to enhance sample conductivity and prevent charge accumulation that could lead to image blurring. The elytra were then observed using a scanning electron microscope (SEM) at an appropriate accelerating voltage. A region with a clear field of view containing the complete elytra outline was selected, and a high-resolution image was captured at 1 mm magnification to obtain the electron microscope image.

[0041] Step 2: Before importing into CATIA, the electron microscope image needs to be processed to make the outline clearer for subsequent drawing. Import the electron microscope image into Photoshop, adjust the brightness and contrast to make the outline of the elytra clearly demarcate from the background, remove noise, then select the outer outline and internal structure edges of the elytra, generate vector paths, and export as DXF format;

[0042] Step 3: Create a new generative shape design part file in CATIA. Enter the sketch editor and select the XY plane as the drawing plane. Import the DXF format file and use the constraint tool to align the image scale with the CATIA coordinate system. A 1mm line segment in the image corresponds to a length of 1000mm in CATIA. Then select the contour command and click on key points along the outer contour of the elytra in the image to generate a continuous spline curve. Smooth the spline curve to make the contour closer to the smooth effect of the schematic diagram, and use the connect command to merge the beginning and end points. Next, draw the internal staggered support structure unit. Use the same contour tool to draw the support structure and edge details inside the elytra. For symmetrical structures, draw one half first, and then use the mirror command to generate the other half. Use the topology offset command to process the obtained planar sketch to generate the overall anti-collision beam structure. Then, in the middle part of the anti-collision beam, merge the reinforcing ribs 2 through Boolean operations to finally obtain the main body 1 of the anti-collision beam.

[0043] The beetle-inspired elytra structure perfectly replicates the core microscopic shape features of the cross-section of the beetle elytra of the *Gnaphalium affine*, including staggered honeycomb support units, gradient wall thickness, and elastically connected node design. This precise replication of microstructures allows the main body of the anti-collision beam 1 to inherit the mechanical advantages of the prototype structure, achieving a significant performance improvement. Simultaneously, the main body of the anti-collision beam 1 exhibits synergistic optimization of anisotropic mechanical properties. Its staggered support structure units ensure high load-bearing capacity in the axial-major collision load direction while also considering deformation resistance in in-plane and oblique-offset collision and oblique collision load directions. This solves the technical pain point of traditional anti-collision beams, which have excellent performance in the main direction but a sharp drop in performance in non-major directions, significantly improving the safety protection level of automobiles in complex collision scenarios.

[0044] The beetle-inspired elytra structure also integrates reinforcing ribs 2 with elliptical through-holes, achieving synergistic optimization of macroscopic structural enhancement and biomimetic performance. The beetle-inspired elytra structure with reinforcing ribs 2 is integrally printed into the main body 1 of the crash beam using additive manufacturing. The reinforcing ribs 2 are not simply structural superpositions, but rather, through topological matching of the rib layout and elliptical through-holes, significantly enhance the impact resistance of the crash beam while achieving lightweighting. The reinforcing ribs 2 are arranged along the axial direction and the main in-plane load-bearing direction of the main body 1, forming a collaborative load-bearing system with the main body 1. The elliptical through-holes on the reinforcing ribs 2 are oriented with their major axis along the main load direction (i.e., the main in-plane load-bearing direction of the main body 1), avoiding the stress concentration problem of circular through-holes and overcoming the brittle fracture defect at the corners of square through-holes—the elliptical arc transition structure can evenly distribute the impact load along the major axis to the entire rib, and then transfer it to the biomimetic microstructure of the main body 1, achieving layered load transfer and full-domain stress dispersion.

[0045] like Figure 6 As shown, the woodpecker's beak has a circular, curved shape, which effectively disperses impact force and reduces stress concentration; its internal surface exhibits a wavy feature, enhancing structural stability. Macroscopically, by introducing the circular curvature, the introduced circular support structure possesses excellent load-bearing capacity and impact resistance, providing a multi-level buffering mechanism and enhancing energy absorption efficiency. Microscopically, by introducing the wavy feature, anisotropic mechanical properties are achieved, adapting to forces from multiple directions. The specific steps for constructing the woodpecker-beak-inspired negative Poisson's ratio structure are as follows:

[0046] Step 1: Construct two mutually perpendicular circular rings using 3D modeling software. The centers of the two circular rings coincide and their dimensions are the same.

[0047] Step 2: Construct four wavy support structures, A, B, C, and D, uniformly along the circumference on one of the circular rings. Construct four wavy support structures, E, F, G, and H, uniformly along the circumference on the other circular ring (to reflect anisotropic mechanical properties and adapt to multi-directional forces). The wavy support structures are generated by scanning a path using a circular outline and a sine function y=2sin(0.5x−1). The ends of A, B, E, and F that are away from the first circular ring are located in the same plane, and the ends of C, D, G, and H that are away from the first circular ring are located in the same plane.

[0048] Step 3: Construct ring 2 through A, E, C, and G, and ring 2 through B, F, D, and H to obtain the woodpecker beak negative Poisson's ratio structural unit;

[0049] Step 4: Linearly array the woodpecker beak negative Poisson's ratio structural units along the X-axis, Y-axis and Z-axis respectively. Multiple woodpecker beak negative Poisson's ratio structural units distributed in a three-dimensional grid array are combined to form a woodpecker beak negative Poisson's ratio structure.

[0050] During impact, the woodpecker-beak-inspired negative Poisson's ratio structure, when subjected to excessive impact force, firstly undergoes bending, compression, and torsional deformation, dissipating impact energy through plastic yielding. Secondly, the ring structures (ring one and ring two) introduced during impact generate interfacial friction, further dissipating energy. This structure exhibits high strength and good deformation capacity, resulting in a lower peak force and higher specific energy absorption under the same conditions.

[0051] like Figure 7 As shown, radiolarians, living in a marine planktonic environment, are susceptible to seawater impact during their long evolutionary process. Therefore, during their silica deposition, silica molecules within the cytoplasm self-assemble into a network structure—a foam-like hexagon. Simultaneously, influenced by cell surface tension and internal pressure, they spontaneously form a centrosymmetric and radially extended morphology. This structure possesses both lightweight and high rigidity, supporting the cell morphology and dispersing stress during water flow impact. The specific steps for constructing a radiolarian-like structure are as follows:

[0052] Step 1: Open the electron microscope image of the radiolarian in Photoshop. Adjust the contrast and noise reduction to make the spines and mesh outlines on the surface clearer. Then, use the quick selection tool to select a representative unit outline, convert it to a vector path, and export it as a DXF format.

[0053] Step 2: Reconstruct the surface feature elements of the radiolarian in CATIA. Create a new generative shape design part file in CATIA, enter the sketch editor, select the XY plane as the drawing plane, import the DXF format file, and use the constraint tool to align the image scale with the CATIA coordinate system. Use the contour tool to trace the inner and outer contours of the star-shaped feature along the edge of the image to obtain a hexagonal sketch. Input the sphere radius r=5mm to generate a complete sphere as the projection target. Select the previously drawn sketch, select the spherical projection command, set the projection distance to 10mm, and the number to 2 layers. Copy the projected feature along the circumference of the sphere, select the center of the sphere as the array center axis, input the array number to 12, and the angle interval to 30° to obtain the radiolarian structural element;

[0054] Step 3: Linearly array the radiolarian structural units along the X-axis, Y-axis and Z-axis respectively. Multiple radiolarian structural units distributed in a three-dimensional grid array are combined to form a radiolarian-like structure.

[0055] The radiolarian-inspired structure is easily deformable and conforms to the geometric geodesic dome model, ensuring structural uniformity while maximizing the support efficiency of the skeleton. It has excellent dynamic impact energy absorption and strong toughness, making it suitable for high-speed, strong impacts on the passenger side and asymmetrical collisions on both sides.

[0056] The main body 1 of the anti-collision beam of this invention adopts a biomimetic design based on the dorsal wall structure of a beetle elytra to create a novel anti-collision beam. Reinforcing ribs 2 are added internally to enhance its impact resistance. Two lightweight, high-strength biomimetic structures with buffering, impact-resistant, and energy-absorbing properties are designed and filled into corresponding energy-absorbing boxes 4. The left energy-absorbing box 4 is filled with a woodpecker-beak-inspired negative Poisson's ratio structure—excellent in quasi-static compression energy absorption and deformation stability, suitable for high-frequency, low-speed scraping and offset collisions on the driver's side. The right energy-absorbing box 4 is filled with a radiolarian-inspired structure—excellent in dynamic impact energy absorption and high toughness, suitable for high-speed, strong impacts on the passenger side and asymmetrical collisions on both sides.

[0057] Nickel-titanium alloys possess superelasticity, shape memory effect, and excellent fatigue resistance. They can stably absorb energy through reversible deformation, balancing lightweight and impact resistance. Biomimetic lattice structures based on biological prototypes can maximize energy absorption efficiency, and the shape of biomimetic anti-collision beams can optimize stress distribution and improve load dispersion capabilities.

[0058] In summary, the differentiated biomimetic lattice structure of the anti-collision beam body 1 and the energy-absorbing box 4 designed in this invention forms a collaborative energy absorption system, achieving full-process optimization of collision load gradient buffering, energy stratified dissipation, and precise deformation control. Load gradient buffering: The anti-collision beam body 1 first buffers the instantaneous load at the initial stage of the collision, reducing the peak load and creating stable conditions for subsequent energy absorption by the energy-absorbing box 4. Energy stratified dissipation: The anti-collision beam body 1 dissipates the collision energy, and the remaining energy is further stratified and dissipated by the biomimetic lattice structure of the energy-absorbing box 4. Precise deformation control: The load-bearing structures of the anti-collision beam body 1 and the energy-absorbing box 4 work together to precisely control the structural deformation boundary, while ensuring the integrity of the vehicle's longitudinal beams, preserving sufficient survival space for occupants. The performance advantages of this collaborative system far exceed the traditional combination of anti-collision beam + energy-absorbing box, achieving a system-level performance improvement of 1+1>2.

[0059] The anti-collision beam body 1 and energy-absorbing box 4 of this invention have excellent energy absorption capacity and shape self-restoration capability, and can be reused, reducing automobile maintenance costs. This device is manufactured using additive manufacturing technology with nickel-titanium alloy as the material. Utilizing the shape memory properties of nickel-titanium alloy, used automotive passive energy-absorbing devices can be disassembled and heated to restore their original shape for reuse, reducing automobile maintenance costs and solving the problem that traditional anti-collision beams and energy-absorbing boxes are easily broken upon impact and cannot be reused.

[0060] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A bionic passive energy-absorbing device for a vehicle based on a nickel-titanium alloy, characterized in that, The crash beam body (1) is fixedly provided with two energy absorption boxes (4) on one side, the energy absorption boxes (4) are filled with bionic energy absorption inner cores (7), the materials of the crash beam body (1), the energy absorption boxes (4) and the bionic energy absorption inner cores (7) are nickel-titanium alloy, and the crash beam body (1), the energy absorption boxes (4) and the bionic energy absorption inner cores (7) are integrally printed by additive manufacturing; The bionic energy absorption inner core (7) is a woodpecker beak negative Poisson's ratio structure or a radiolarian structure; The energy absorption box (4) close to the main driver side is filled with a woodpecker beak negative Poisson's ratio structure, and the energy absorption box (4) close to the co-pilot side is filled with a radiolarian structure; The specific steps for constructing the woodpecker beak negative Poisson's ratio structure are as follows: Step 1, based on a three-dimensional modeling software, two mutually perpendicular circular rings I are constructed; Step 2, four wave-shaped support structures A, B, C and D are uniformly constructed on one of the circular rings I in the circumferential direction, and four wave-shaped support structures E, F, G and H are also uniformly constructed on the other circular ring I in the circumferential direction, the wave-shaped support structures are generated by a circular contour cooperating with a path scanning generated by a sine function, wherein the ends of A, B, E and F away from the circular ring I are located in the same plane, and the ends of C, D, G and H away from the circular ring I are located in the same plane; Step 3, a circular ring II is constructed through A, E, C and G, and a circular ring II is constructed through B, F, D and H, so as to obtain a woodpecker beak negative Poisson's ratio structure unit; Step 4, the woodpecker beak negative Poisson's ratio structure unit is linearly arrayed in the X-axis direction, the Y-axis direction and the Z-axis direction respectively, and a plurality of woodpecker beak negative Poisson's ratio structure units in three-dimensional grid array distribution are combined into a woodpecker beak negative Poisson's ratio structure.

2. The bionic passive energy-absorbing device for vehicles based on nickel-titanium alloy according to claim 1, characterized in that, The crash beam body (1) is a beetle elytra structure, taking the elytra of the magic iron yao beetle as a bionic prototype, the cross-sectional surface of the magic iron yao beetle elytra is selected for fine topological structure design, and the beetle elytra structure is constructed through microscopic imaging and three-dimensional reconstruction technology, and the specific steps are as follows: Step 1, the elytra cross section of the magic iron yao beetle elytra is cut by a microtome, the thickness of the section is uniform, and the section is flat without burrs, half of the section is fixed on the electron microscope sample table with conductive glue, then gold spraying treatment is carried out to enhance the conductivity of the sample, scanning electron microscope observation is carried out, a region with clear field of view and complete elytra contour is selected, 1mm magnification is selected for shooting, and an electron microscope photo is obtained; Step 2, the electron microscope photo is imported into the Photoshop image software, the brightness and contrast are adjusted, the outline of the elytra and the background are clearly separated, the noise points are removed, then the outer contour and the internal structure edge of the elytra are selected, a vector path is generated, and a DXF format file is exported; Step 3, in CATIA, a new generative surface design part file is created, the sketch editor is entered, the XY plane is selected as the drawing plane, the DXF format file is imported, the scale of the picture is aligned with the coordinate system of CATIA by using the constraint tool, the line segment of 1mm in the picture corresponds to the length of 1000mm in CATIA, then the contour command is selected, the outer contour of the beetle sheath in the picture is clicked in sequence, a continuous spline curve is generated, the spline curve is smoothed, and the first and last points are merged by using the connection command; the internal staggered support structure unit is drawn, the same contour tool is used to draw the support structure and edge details inside the beetle sheath, for the symmetrical structure, half is drawn first, and the other half is generated by using the mirror command; the planar sketch obtained is processed by using the topology offset command to generate the whole anti-collision beam structure, then the reinforcing rib plate (2) is merged in the middle part of the anti-collision beam structure by using the Boolean operation, and finally the anti-collision beam main body (1) is obtained.

3. The bionic passive energy-absorbing device for vehicles based on nickel-titanium alloy according to claim 2, characterized in that, The reinforcing rib plate (2) is provided with a plurality of elliptical through holes.

4. The bionic passive energy-absorbing device for vehicles based on nickel-titanium alloy according to claim 1, characterized in that, The specific steps of constructing the radiolarian structure are as follows: Step 1, open the electron microscope picture of the radiolarian in Photoshop, adjust the contrast and denoising to make the surface spines and grid contours clearer, select a unit contour by using the quick selection tool, convert it into a vector path, and then export it as a DXF format file; Step 2, restore the surface feature unit of the radiolarian in CATIA, create a new generative surface design part file in CATIA, enter the sketch editor, select the XY plane as the drawing plane, import the DXF format file, align the scale of the picture with the coordinate system of CATIA by using the constraint tool, use the contour tool to draw the inner and outer contours of the star-shaped feature along the edges of the picture to obtain a hexagon-like sketch; input the spherical radius r=5mm to generate a complete spherical surface as a projection target, then select the previously drawn sketch, select the spherical projection command, set the projection distance to 10mm and the number to 2 layers, copy the projected features along the circumferential direction of the sphere, select the center of the sphere as the array center axis, input the array number 12 and the angle interval 30° to obtain the radiolarian structure unit; Step 3, linearly array the radiolarian structure units along the X-axis direction, Y-axis direction and Z-axis direction respectively, and combine a plurality of three-dimensional grid array distributed radiolarian structure units to form the radiolarian structure.

5. The bionic passive energy-absorbing device for vehicles based on nickel-titanium alloy according to claim 1, characterized in that, The anti-collision beam main body (1) is provided with two groups of bolt holes (6) on one side, each group of bolt holes (6) is connected with an energy absorption box (4) through a fastening bolt (3), and the energy absorption box (4) is provided with a limiting hole (5) away from the anti-collision beam main body (1).

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