Suture-helix composite plate bionic energy absorption structure

Abstract

The present application is suitable for the technical field of spiral layered structure, and provides a suture-spiral composite plate bionic energy absorption structure which combines the advantages of layered spiral structure and suture structure. The structure comprises: a plurality of unit layer groups, each unit layer group comprising a plurality of unit layers, the plurality of unit layer groups being periodically arranged along the layering direction. According to the principle of bionics, the method of similarity analysis is used to confirm that the core is to compare the chitinous suture structure in the iron beetle with the selected elements to bionically generate a new energy absorption structure from the angles of structural similarity, functional similarity and boundary similarity. According to the structural feature extraction and spiral structure fusion of the chitinous characteristics in the iron beetle, a three-dimensional macroscopic preliminary suture-spiral composite plate bionic structure is established, and the range of each element and its size is determined for structure construction and size parameter optimization. The present application can reduce the mass of parts and improve the energy absorption efficiency.

Description

Technical Field

[0001] This invention belongs to the field of helical layered structure technology, and particularly relates to a biomimetic helical structure that is adaptable to multiple waves and functions. Background Technology

[0002] Helical layered structures, with their lightweight, flexible assembly, high strength, and high specific energy absorption, have been widely used in vehicles, ships, aerospace, and marine engineering. With the continuous development of additive manufacturing technology, irregular material structures can also be easily manufactured, making it possible to move helical layered composite structures from finite element simulation to experimental applications.

[0003] Biological structures such as shells, spider silk, and skeletons have been used to develop various lightweight, high-strength, and high-toughness biomimetic structures, opening up new avenues for lightweight structure design. Recent research shows that a marine creature called the mantis shrimp can easily break the shells of mollusks to hunt using its hammer-like pincers, which are composed of spiral chitinous layers. This spiral layered structure in the mantis shrimp enhances the stiffness, strength, and rigidity required for animal protection while allowing for movement and predation. The carapace of the iron beetle possesses excellent mechanical properties and flexibility, characterized by a large groove connected to a small snap-fit. This protects the connection between the layers and the matrix, while the connection deforms under stress without destroying the structure, improving energy absorption and reducing impact.

[0004] Helical structures, such as helical column structures, sandwich structures, helical honeycomb structures, and foam structures, are widely used in machinery, construction, automotive, aerospace, and medical fields due to their excellent strength, energy absorption, thermal insulation, noise suppression, and lightweight properties. However, current research mainly focuses on the fabrication, crack torsion modes, and damage propagation behavior of these structures, with little attention paid to the damage mechanisms between layers and the matrix. In fact, each thin layer in a helical layered structure deforms during impact, resulting in complex damage mechanisms such as fiber breakage, matrix cracking, and fiber-matrix interface debonding. These factors significantly impact the load-bearing capacity and failure of the entire structure. To improve the energy absorption capacity of helical layered structures, researchers are attempting to learn from biological structures that have adapted to and thrived in their environments. Therefore, the design and performance studies of the interlayer and matrix in helical layered structures have become a research hotspot in the field of energy absorption, but currently, there are no helical layered structures incorporating the suture structure of iron beetles. Summary of the Invention

[0005] The purpose of this invention is to provide a biomimetic energy-absorbing structure of a stitch-spiral composite plate, which aims to solve the problems existing in the prior art as identified in the background art.

[0006] The present invention is implemented as follows: a suture-spiral composite plate biomimetic energy-absorbing structure, the structure comprising:

[0007] A stitch-spiral composite plate biomimetic energy-absorbing structure is characterized by comprising: a stitch structure unit 1, with a crescent-shaped cross-section 1.1, a convex groove 1.2 on the inner side of the crescent, and a π-shaped protruding structure 1.3 on the outer side of the crescent; the connection between each structural unit is similar to the stitch structure of an iron beetle's shell, and each structural unit is connected by the outer π-shaped protruding structure from the wide part of the inner convex groove and moves to the narrow part to complete the connection, arranged sequentially into a single-layer structure 2; the unit layers are twisted at a certain angle to form a stitch-spiral composite plate biomimetic energy-absorbing structure 3, which can reduce the mass of the parts and improve the energy absorption efficiency.

[0008] Preferably, the initial total length of the unit suture of the preliminary suture-spiral energy-absorbing structure is L = 7 mm, ranging from 6 to 8 mm; the initial value of the long hole is B1 = 5.5 mm, ranging from 5 to 6 mm; the initial value of the short hole is B2 = 3.5 mm, ranging from 3 to 4 mm; the initial value of the cavity distance from the edge is C = 7 mm, ranging from 6 to 8 mm; the initial value of the outer radius of the protruding part is R = 10.5 mm, ranging from 10 to 11 mm; and the base material adopts a hollow structure with an outer radius of R1 = 6 mm and an inner radius of R2 = 4 mm.

[0009] Preferably, in the optimal energy-absorbing suture-spiral structure after topology optimization, the structural parameters are: total length L = 6.6302 mm, long hole B1 = 5.8922 mm, short hole B2 = 3.0545 mm, edge of the recess C = 6.0559 mm, and outer radius of the protruding part R = 10.034 mm.

[0010] Preferably, the suture-spiral composite plate structure is formed by fusing a spiral layered structure and a suture structure.

[0011] The stitched-spiral composite panel's biomimetic energy-absorbing structure increases the energy-absorbing length, enhancing its energy absorption and dispersion capabilities. This allows the structure to effectively absorb and disperse energy when subjected to impacts, vibrations, or other external forces, mitigating structural damage and destruction. The spiral layered structure provides robust frame support, enhancing the overall structural strength and stability. It can withstand external loads and pressures, reducing structural failure caused by stress concentration while maintaining sufficient strength. This lightweight design reduces material requirements and lowers manufacturing costs. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the extraction of the biomimetic iron beetle suture structure provided in an embodiment of the present invention;

[0013] Figure 2 This is a schematic diagram of the minimum structural unit and its size parameters provided in the embodiments of the present invention;

[0014] Figure 3 This is a schematic diagram of a single-layer structure of the suture-spiral biomimetic structure provided in an embodiment of the present invention;

[0015] Figure 4 This is an impact simulation cloud diagram of a single-layer structure of the suture-spiral biomimetic structure provided in an embodiment of the present invention;

[0016] Figure 5 This is a schematic diagram of the combination of structural units of different layers provided in the embodiments of the present invention;

[0017] Figure 6 This is a schematic diagram of a simulated stitch-spiral composite material plate provided in an embodiment of the present invention;

[0018] Figure 7 This is a schematic diagram of the deformation after simulation of the initial data provided in the embodiment of the present invention;

[0019] Figure 8 This is a data diagram corresponding to different parameters L, B1, and B2 provided in an embodiment of the present invention;

[0020] Figure 9 This is a diagram showing the relationship between strain energy and dimensions in a stitch-spiral composite biomimetic structure provided in an embodiment of the present invention.

[0021] Figure 10 The suture-spiral composite plate biomimetic structure is prepared by photopolymerization 3D according to the embodiments of the present invention;

[0022] Figure 11 The upper and lower surfaces of a stitch-spiral composite plate biomimetic structure provided in this embodiment of the invention after an impact test;

[0023] Figure 12 This is a schematic diagram of the equivalent stress and energy absorption of a stitch-spiral composite plate biomimetic structure in an impact test, provided by an embodiment of the present invention.

[0024] Figure 13 This is an internal energy diagram of a quasi-static compression simulation of a suture-spiral composite plate biomimetic structure provided in an embodiment of the present invention.

[0025] Figure 14 This is an internal energy diagram of an impact simulation of a stitch-spiral composite plate biomimetic structure provided in an embodiment of the present invention. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0027] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0028] like Figure 1 The diagram shown is a schematic diagram of the extraction of sutures in a suture-spiral composite biomimetic structure provided by an embodiment of the present invention. The structural feature analysis and extraction start from the suture characteristics of the shell of an iron beetle. Through similarity analysis and extraction of the suture structure of the shell, the main structural elements and structural mechanisms are extracted. According to the principles of bionics, the similarity analysis method is used to confirm the selected elements from the perspectives of structural similarity, functional similarity and boundary similarity.

[0029] like Figure 2 As shown, the structural parameters in the minimum structural unit include a total suture length L of 7 mm, optimized within the range of 6 mm to 8 mm. The width of the elongated hole B1 is 5.5 mm, optimized within the range of 5 mm to 6 mm. The width of the short hole B2 is 3.5 mm, optimized within the range of 3 mm to 4 mm. The edge C of the recess is 7 mm, optimized within the range of 6 mm to 8 mm. Finally, the outer diameter of the protruding portion R is 10.5 mm, optimized within the range of 10 mm to 11 mm.

[0030] like Figure 3-4 As shown, the single-layer panel style is characterized by a standard spiral composite panel with a width of 104 mm. Each layer consists of 6 tubular cells with an outer diameter of 6 mm and an inner diameter of 4 mm. These units are interconnected using four suture-shaped structures, and additional suture structures are combined between the layers to ensure connectivity.

[0031] like Figure 5 As shown in the diagram, the energy absorption effect of a single stitch structure is limited. Therefore, combining it with a spiral structure can achieve effective energy absorption, wear resistance, and extended service life. The single-layer structural units involved are overlapped in multiple layers and twisted 24° from top to bottom, resulting in a total of 3 layers.

[0032] like Figure 6As shown, (a) depicts the stitching between elements, with the sides fixed and a 2000N vertical upward force applied to the underside of the protruding portion, while a 2000N vertical downward force is applied to the hollow portion. Choosing a 2000N force allows for a more comprehensive understanding of energy absorption and deformation, facilitating optimization and adjustment. The overall structure of the composite plate is placed on a fixed rigid platform using a stainless steel indenter. The indenter is set to a downward velocity of 400 m / s, as shown in (b). This velocity selection allows for structural decomposition, enabling detailed observation of the model's deformation and analysis of its energy absorption characteristics. The friction coefficient used in the simulation is set to 0.2, as this range is consistent with the typical friction coefficient in compression experiments, which is typically between 0.1 and 0.5. To ensure accurate results, a fine mesh with a 1 mm mesh size is used. The cell consists of 17530 nodes and 80678 elements. The entire model comprises 258513 nodes and 1031002 elements.

[0033] like Figure 7 As shown, the deformation of each part after stress is (a) the joint between units; (b) the overall structure of the composite plate. Consideration is given to significance levels, where a p-value less than 0.0001 is considered significant. In this study, L, B1, and B2 were found to have a significant impact on the peak stress of the model. Furthermore, B1 and B2 had a more significant impact on the specific energy absorption of the model. Conversely, the coefficients C and R had the least impact on energy absorption performance. The following equations represent the simple multiple regression equations for PS and SEA, respectively.

[0034] PS=1515.22-92.09L-183.8B1+203.02B2-19.62C+2.64R

[0035] SEA=53.24-2.26L+0.53B1-3.06B2-0.8C-0.22R

[0036] like Figure 8 As shown, by combining the regression fitting equation with the performance parameters, the relationship between the interlayer stitching coefficient and the performance indices can be observed as follows: PS (equivalent stress) initially increases with increasing h, then decreases. On the other hand, SEA (total energy absorption) increases linearly with increasing K, whereas it initially decreases with increasing h, then increases. In optimizing the structural parameters using the response surface methodology, the goal is to minimize PS and maximize SEA.

[0037] like Figure 9As shown in the figure, as the diameter increases, the internal energy (G) first decreases and then increases. When the length of the large notch (E) and the edge distance c (B) increase respectively, the internal energy of the structure shows a decreasing trend. When the diameter (A) and the length of the large notch (E) increase simultaneously, the internal energy of the structure first decreases and then increases. Similarly, when the diameter (A) and the edge distance c (B) increase simultaneously, the internal energy (G) first decreases and then increases.

[0038] like Figure 10 As shown, the structural parameters of the spiral layer are linked to its relative density to construct a stitch-spiral composite plate biomimetic structure, and the performance is verified through impact simulation tests.

[0039] The required 3D model is created using computer-aided design (CAD) software. After the design is completed, the model is converted into STL format for subsequent printing preparation.

[0040] Slicing Processing: The STL format 3D model is imported into the slicing software for slicing. The slicing software decomposes the model into multiple thin slices, each with a thickness of 0.02mm, and generates printing path information for each layer to determine the trajectory of the light beam during printing.

[0041] Printing preparation: Select photosensitive resin material and transmit the printing path information generated by the slicing software to the printer control system.

[0042] 3D Printing: Start the printer, light intensity 500mW / cm² 2 The printing speed is 10mm / h. The light source shines on the first layer of resin, which cures and forms the first layer. Then the work platform is lowered a certain distance to expose the next layer of resin to the light source. The light beam shines on the next layer again, and this process is repeated until the entire model is printed.

[0043] Post-processing: After printing is completed, the printed object is removed from the printing platform and post-processing work such as removing the support structure, cleaning, and curing is carried out.

[0044] like Figure 11 As shown, an impact test was conducted to verify the accuracy of the simulation test;

[0045] Combination Figures 12-14 The stitch-spiral composite plate biomimetic structure provided in this embodiment is controllable and repeatable. It can customize spiral layered energy-absorbing structures with different numbers of layers according to specific needs, thereby improving the energy absorption effect of the obtained spiral layered structure and promoting the development and innovation of structural engineering and energy-absorbing structure fields.

[0046] Compared with existing technologies, this invention has the following advantages: This stitch-spiral composite plate biomimetic structure increases the energy-absorbing length, improving energy absorption and dispersion capabilities. This allows the structure to effectively absorb and disperse energy when subjected to impact, vibration, or other external forces, reducing structural damage and destruction. For the first time, a stitch structure is used to prevent fiber breakage and matrix cracking under stress. Combined with the traditional spiral structure, what was traditionally considered a disadvantage becomes an advantage. The combination effectively extends the service life of the energy-absorbing structure, solving the problem of short service life under high stress. The spiral layered structure provides robust frame support, enhancing the overall structural strength and stability. It can withstand external loads and pressures, reducing structural damage caused by stress concentration. Furthermore, the structure is compact, suitable for use in precision instruments, and easy to manufacture. Individual units can be produced using 3D printing technology, and any number of units and layers can be assembled according to the environment. The stitch-spiral composite plate biomimetic structure described in this invention makes the overall structure lightweight while maintaining sufficient strength. This lightweight design reduces material requirements and manufacturing costs. Therefore, this invention has significant practical value.

[0047] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A biomimetic energy-absorbing structure of a stitch-spiral composite plate, characterized in that, It includes: several suture structure units (1), the cross-section of the suture structure unit (1) is crescent-shaped (1.1), the inner side of the crescent-shaped (1.1) is provided with a "convex" groove (1.2), and the outer side is provided with a "π" shaped protruding structure (1.3); between two adjacent suture structure units (1), the "π" shaped protruding structure (1.3) on the outer side of one suture structure unit (1) enters from the wide part of the "convex" groove (1.2) on the inner side of the other suture structure unit (1) and moves to the narrow part to complete the connection; several suture structure units (1) are arranged in sequence to form a single-layer structure (2); several single-layer structures (2) are twisted to a set angle and stacked to form the suture-spiral composite plate biomimetic energy-absorbing structure (3).

2. The biomimetic energy-absorbing structure of a stitch-spiral composite plate according to claim 1, characterized in that, The dimensional parameters of the suture structure unit (1) are as follows: the total length L is the total length of the unit suture along its arrangement direction, and the value range is 6 to 8 mm; the long hole B1 is the width of the wide hole of the "convex" groove (1.2), and the value range is 5 to 6 mm; the short hole B2 is the width of the narrow hole of the "convex" groove (1.2), and the value range is 3 to 4 mm; the distance C from the recess to the edge is the distance from the recess to the edge of the crescent shape (1.1), and the value range is 6 to 8 mm; the outer radius R of the protruding part is the outer radius of the "π" shaped protruding structure (1.3), and the value range is 10 to 11 mm; the crescent shape (1.1) structure of the suture structure unit (1) adopts a hollow structure with a hollow center, and the outer radius R1 = 6 mm and the inner radius R2 = 4 mm of the hollow structure.

3. The biomimetic energy-absorbing structure of a stitch-spiral composite plate according to claim 2, characterized in that, The topology-optimized dimensions of the suture structure unit (1) are as follows: total length L = 6.6302 mm, long hole B1 = 5.8922 mm, short hole B2 = 3.0545 mm, distance from the recess to the edge C = 6.0559 mm, and outer radius R of the protruding part of the "π"-shaped protruding structure (1.3) = 10.034 mm.

4. A biomimetic energy-absorbing structure for a stitch-spiral composite plate as described in any one of claims 1-3, characterized in that, The suture-spiral composite plate structure is formed by fusing a spiral layered structure and a suture structure.

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