Improved anti-impact energy-absorbing structure of snail shell imitating square tube and application of improved anti-impact energy-absorbing structure

Abstract

The invention belongs to the technical field of anti-impact protection. According to the snail shell imitating square tube improved anti-impact energy absorption structure and the application, the structural monomers or the structural modular array can be used for dynamic load protection. Under the action of an axial compression load, the structure realizes a multi-layer and progressive collapse path, and has low initial peak crushing force and staged and approximately linear increasing force-displacement response characteristics. According to the bionic structure, the energy absorption efficiency of the rectangular pipe is effectively improved under the condition that the mass and the manufacturing complexity are not increased, and the bionic structure is suitable for vehicle anti-collision systems, rail transit buffer devices and other anti-impact protection fields.

Description

Technical Field

[0001] This invention belongs to the field of impact protection technology. It relates to an improved impact-absorbing structure using a snail-shell-inspired square tube and its application; the individual structural units or modular arrays of the structure can be used for dynamic load protection. Background Technology

[0002] In fields such as protective engineering, transportation equipment, and aerospace, structures must possess excellent energy absorption and impact resistance when subjected to transient high-energy loads such as explosive impacts and drop collisions to ensure the safety and reliability of the system. In recent years, sandwich structures have become an important research direction in protective structures due to their lightweight, high specific strength, and excellent energy dissipation characteristics. The core layer topologies of sandwich structures are diverse, including honeycomb, foam, lattice, and origami types. Although these structures perform well under static or low-velocity impact conditions, they still suffer from problems such as high initial peak force, unstable collapse modes, and complex manufacturing processes under high-speed or strong impact environments, limiting their further engineering applications.

[0003] Compared with various complex sandwich structures, thin-walled rectangular tubes have always been one of the most typical energy-absorbing elements due to their simple geometry, mature manufacturing process, and high energy absorption efficiency. They are widely used in fields such as automotive anti-collision beams, buffer devices, and protective components for rail vehicles. However, traditional rectangular tubes have obvious shortcomings under axial compression: (1) the initial peak crushing force is high, which easily generates an excessive load peak in the early stage of impact, causing the impact energy to be transferred to the protected component; (2) the energy absorption mode is singular, and the plastic wrinkles are unevenly formed, resulting in low energy dissipation efficiency; (3) the deformation mode is limited by axisymmetry, and the collapse process is difficult to control precisely, affecting the stability and repeatability of the energy absorption process. Therefore, traditional rectangular tubes cannot simultaneously achieve the comprehensive performance of low initial peak crushing force and high energy absorption capacity, and it is urgent to achieve a performance breakthrough through structural innovation.

[0004] In recent years, biomimetic design concepts have provided new insights into optimizing the impact resistance of thin-walled structures. Over long periods of evolution, plants and animals in nature have developed various structural forms with excellent impact resistance, protection, or energy dissipation properties. Examples include the gradient layered structure of bamboo culms, the multi-cavity composite structure of beetle elytra, and the spirally stacked shells of snails. These natural structures, while maintaining lightweight design, effectively disperse and absorb external impact energy, providing important inspiration for the lightweight and protective design of engineering structures.

[0005] Currently, numerous patents both domestically and internationally have attempted to apply biomimetic concepts to energy-absorbing structure design. For example, patent CN116279251A proposes a cylindrical energy-absorbing box based on bamboo joint biomimicry, which improves energy absorption performance through partitions; patent CN119057077A discloses a bamboo-tube-shaped beetle elytra-inspired biomimetic energy-absorbing superstructure and its preparation method, which improves energy absorption efficiency through a helical array of cellular structures. These research and patent achievements demonstrate that biomimetic structure design has significant advantages in improving the impact resistance and lightweight potential of thin-walled energy absorbers, but further optimization of low-cost manufacturing feasibility is still needed to meet the application requirements of complex engineering environments. Summary of the Invention

[0006] The purpose of this invention is to address the problems of high initial peak crushing force, low energy absorption efficiency, and difficult-to-control deformation mode in traditional rectangular tube structures by making minor structural modifications, without altering the mass of the rectangular tube and while maintaining the low-cost advantage of rectangular tube thin-walled energy absorbers. Inspired by snail shells, an improved impact-resistant energy-absorbing structure based on snail shells is proposed, under conditions of controllable cost and simple process. The individual structural units can be used in impact protection applications such as vehicle energy-absorbing boxes; multiple units arranged in a two-dimensional or three-dimensional array can serve as the core layer of a "sandwich" structure for blunt force protection in individual soldier protective equipment.

[0007] The structural technical solution proposed in this invention is:

[0008] An improved impact-resistant energy-absorbing structure using a snail-shell-inspired square tube, without altering the diameter and height of a traditional rectangular tube. Under this premise, the rectangular tube is radially divided into four quadrants: the first quadrant substructure, the second quadrant substructure, the third quadrant substructure, and the fourth quadrant substructure. The axial height of each quadrant is designed with a gradient height, mimicking the shape of the snail shell opening. The height of the first quadrant substructure is equal to the residual height of the rectangular tube after axial compression into the compaction stage. Consistent, the height difference between the first quadrant substructure and the fourth quadrant substructure The height difference between the fourth quadrant substructure and the third quadrant substructure is The height difference between the third quadrant substructure and the second quadrant substructure is The height of the substructure in the second quadrant and the height of the rectangular tube Consistent; Rectangular ribs are set inside the biomimetic structure according to the quadrant division. The outer side of the ribs is connected to the wall of the biomimetic structure, and the inner side intersects each other in a "+" shape. The height of the ribs is equal to the height of the higher of the two adjacent quadrant substructures. The aforementioned ribs form a spiral-gradient support system in space, causing the rectangular tube to form a multi-layered, progressive collapse path during the compression process.

[0009] Under axial compressive load, the biomimetic structure, relying on its substructures of different heights and the mutual constraint of its internal ribs, achieves a low initial peak crushing force and exhibits a staged, approximately linear increase in crushing force with displacement throughout the entire crushing process. Through the aforementioned biomimetic geometric design, this structure achieves a balance between low initial peak crushing force and high energy absorption performance without increasing mass or compressing manufacturing complexity. This enhances the overall performance of rectangular tube energy-absorbing elements in the field of impact protection and makes it suitable for vehicle collision avoidance systems, rail transit buffer devices, and other impact-resistant energy-absorbing applications.

[0010] This invention relates to the field of protective structure design, specifically disclosing an improved impact-resistant energy-absorbing structure using a snail-shell-inspired square tube, belonging to the technical field of impact-resistant energy-absorbing elements. This structure, without altering the external dimensions and overall height of the traditional rectangular tube, divides the rectangular tube radially into four quadrants, and designs a gradient height for each quadrant based on the geometric characteristics of the snail shell opening. The height of the first quadrant is the residual height of the traditional rectangular tube during the compression and compaction stage. The height in the second quadrant is the total height of the tube. The height differences between adjacent quadrants are as follows: The structure features mutually perpendicular rectangular ribs arranged along the quadrant direction. The outer sides of the ribs connect to the wall, while the inner sides intersect in a cross shape. Their height matches the higher of the two adjacent quadrants, forming a spatial spiral-gradual support system. Under axial compressive loads, this structure achieves a multi-layered, progressive collapse path, exhibiting low initial peak crushing force and a staged, approximately linearly increasing force-displacement response. This biomimetic structure effectively improves the energy absorption efficiency of rectangular tubes without increasing mass or manufacturing complexity, making it suitable for vehicle collision avoidance systems, rail transit buffer devices, and other impact protection applications.

[0011] The beneficial effects of this invention are: by improving the rectangular tube structure through biomimetic methods, the manufacturing cost can be controlled with the help of simple structural design without increasing the mass of the traditional rectangular tube. Compared with the traditional rectangular tube, its energy absorption value (SEA) per unit mass is improved, and its impact efficiency (the ratio of average crushing force to initial peak crushing force) is improved. Attached Figure Description

[0012] Figure 1 Front view, top view, and side view of the improved impact-resistant energy-absorbing structure for a snail-shell-inspired rectangular tube; Figure 2 It is a "sandwich" structure with a core layer made of a snail-shell-like rectangular tube improved for impact resistance and energy absorption. Figure 3The diagram shows a comparison of the compressive force-displacement curves of the PLA material 3D printed structure of the present invention and a traditional rectangular tube of the same mass, wall thickness, diameter, and height under quasi-static compression. The left image shows the rectangular tube, and the right image shows the structure of the present invention. Detailed Implementation

[0013] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0014] Example An improved impact-resistant energy-absorbing structure using a snail-shell-inspired square tube, without altering the diameter and height of a traditional rectangular tube. Under the premise of dividing the rectangular tube radially into four quadrants, the axial height of each quadrant is designed with a gradient height modeled after the shape of a snail shell opening. The height of the first quadrant is the residual height of the rectangular tube when it enters the compaction stage after axial compression. =5mm consistent, wall thickness is 1mm, height difference between substructures in the first and fourth quadrants The height difference between the fourth quadrant substructure and the third quadrant substructure is also... The height difference between the third quadrant substructure and the second quadrant substructure is The height of the substructure in the second quadrant and the height of the rectangular tube Consistent. Rectangular ribs are set inside the biomimetic structure according to the quadrant division. The outer side of the ribs is connected to the wall of the biomimetic structure, and the inner side intersects each other in a "+" shape. The height of the ribs is the same as the higher of the two adjacent quadrant substructures. The aforementioned ribs form a spiral-gradient support system in space, causing the rectangular tube to form a multi-layered, progressive collapse path during the compression process.

[0015] Under axial compressive load, the biomimetic structure, relying on its substructures of different heights and the mutual constraint of its internal ribs, achieves a low initial peak crushing force and exhibits a staged, approximately linear increase in crushing force with displacement throughout the entire crushing process. Through the aforementioned biomimetic geometric design, this structure achieves a balance between low initial peak crushing force and high energy absorption performance without increasing mass or compressing manufacturing complexity. This enhances the overall performance of rectangular tube energy-absorbing elements in the field of impact protection and makes it suitable for vehicle collision avoidance systems, rail transit buffer devices, and other impact-resistant energy-absorbing applications.

[0016] This invention relates to an improved impact-absorbing structure using a snail-shell-inspired rectangular tube, which can be used as the core layer of a "sandwich" cushioning structure. In a single-unit structure, the improved impact-absorbing structure 1 using a snail-shell-inspired rectangular tube is placed between a top plate 2 and a bottom plate 3, with its top and bottom edges contacting and fixed to the top plate 2 and bottom plate 3, respectively. In a two-dimensional array structure, multiple improved impact-absorbing structures 1 using snail-shell-inspired rectangular tubes are arranged along two perpendicular directions, placed between the top plate 2 and bottom plate 3, with their top and bottom edges contacting and fixed to the top plate 2 and bottom plate 3, respectively, forming a two-dimensional array core layer.

[0017] In both structural modes described above, when the structure is subjected to impact loads, the top plate 2 or the bottom plate 3 serves as the impact-bearing surface; when the structure is subjected to explosive loads, the top plate 2 or the bottom plate 3 serves as the blast-facing surface. By improving the plastic deformation of the impact-resistant energy-absorbing structure through snail-shell-like rectangular tubes, impact or explosive energy can be effectively dissipated, achieving a buffer protection function.

[0018] The structure of this invention, 3D printed using PLA material, is compared with the quasi-static compressive force-displacement curve of a traditional rectangular tube of the same mass, wall thickness, diameter, and height under quasi-static compressive force, as shown in the figure below. Figure 3 As shown, by Figure 3 It can be seen that the structure of the present invention no longer exhibits the initial peak value, and the energy absorption value is higher.

[0019] In summary, the above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An improved impact-resistant energy-absorbing structure using a snail-shell-inspired square tube, characterized in that: This energy-absorbing structure is obtained by modifying a rectangular tube, the height of which is... The residual height of the rectangular tube after axial compression and entering the compaction stage is ; The energy-absorbing structure includes a wall and four ribs for dividing the wall into four quadrants; the four quadrants are a first quadrant substructure, a second quadrant substructure, a third quadrant substructure, and a fourth quadrant substructure; The height of the first quadrant substructure is ; Height difference between the first quadrant substructure and the fourth quadrant substructure ; The height difference between the fourth quadrant substructure and the third quadrant substructure is ; The height difference between the third quadrant substructure and the second quadrant substructure is ; The height of the second quadrant substructure is .

2. The improved impact-resistant energy-absorbing structure of a snail-shell-inspired square tube according to claim 1, characterized in that: The outer sides of all four ribs are connected to the wall.

3. The improved impact-resistant energy-absorbing structure of a snail-shell-inspired square tube according to claim 1, characterized in that: The inner sides of the four ribs intersect each other in a cross shape.

4. The improved impact-resistant energy-absorbing structure of a snail-shell-inspired square tube according to claim 1, characterized in that: The height of the rib plate is equal to that of the two adjacent quadrant substructures.

5. An application of the snail-shell-inspired square tube improved impact-resistant energy-absorbing structure as described in claim 1, characterized in that: This energy-absorbing structure is used as the core layer of a "sandwich" cushioning structure.

6. The application of the snail-shell-inspired square tube improved impact-resistant energy-absorbing structure according to claim 5, characterized in that: In the single-unit structure mode, the energy-absorbing structure is placed between the top plate and the bottom plate, with the top of the energy-absorbing structure in contact and fixed to the top plate, and the bottom of the energy-absorbing structure in contact and fixed to the bottom plate.

7. The application of the snail-shell-inspired square tube improved impact-resistant energy-absorbing structure according to claim 5, characterized in that: In the two-dimensional array structure mode, multiple energy-absorbing structures are placed between the top plate and the bottom plate. The top of the energy-absorbing structure is fixed in contact with the top plate, and the bottom of the energy-absorbing structure is fixed in contact with the bottom plate, forming a two-dimensional array core layer.

Images