A fillable zero-poisson's ratio impact-resistant structure and method of making the same

Abstract

The application discloses a fillable zero-Poisson-ratio impact-resistant structure and a manufacturing method thereof, and particularly relates to the technical field of zero-Poisson-ratio structures. In order to solve the problem that most of the existing zero-Poisson-ratio structures are composed of bars and have weak bearing capacity and impact resistance, the impact-resistant structure comprises a plurality of cells arranged in an array, wherein each cell comprises an upper end plate, a middle plate and two receiving sleeves; the middle plate is horizontally arranged; one receiving sleeve is arranged on each of the upper side and the lower side of the middle plate; the two receiving sleeves are both open at both ends; the side wall of each receiving sleeve is a curved surface; the small ends of the two receiving sleeves are fixedly connected to the end face of the middle plate in the longitudinal direction; the interiors of the two receiving sleeves are connected; the upper end plate is fixedly connected to the upper end face of the large end of the upper receiving sleeve; the upper receiving sleeve is connected with the lower receiving sleeve of the adjacent cell above the upper receiving sleeve; and the upper end plate and the middle plate of each adjacent two cells are fixedly connected.

Description

Technical Field

[0001] This invention relates to the field of zero Poisson's ratio structure technology, specifically to a fillable zero Poisson's ratio impact-resistant structure and its manufacturing method. Background Technology

[0002] Poisson's ratio is an elastic constant reflecting the lateral deformation of a material under longitudinal load. Currently, most existing impact-resistant structures are either positive or negative Poisson's ratio structures. Positive Poisson's ratio structures expand laterally under axial impact, while negative Poisson's ratio structures contract inward laterally, neither maintaining their original shape well and thus unsuitable for special conditions requiring strict control of lateral deformation. Therefore, designing an impact-resistant structure with a zero Poisson's ratio effect (i.e., essentially no lateral deformation under longitudinal impact load) is essential. However, most existing zero Poisson's ratio structures are composed of rods, exhibiting low stiffness, poor load-bearing capacity, poor stability, and weak energy absorption and impact resistance. Therefore, designing a zero Poisson's ratio structure with high load-bearing capacity and high impact resistance is of significant engineering importance for the development of impact-resistant structures. Summary of the Invention

[0003] In order to solve the problem that most existing zero Poisson's ratio structures are composed of rods and have weak load-bearing capacity and impact resistance, this invention proposes a fillable zero Poisson's ratio impact-resistant structure and its manufacturing method.

[0004] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows:

[0005] A fillable zero Poisson's ratio impact-resistant structure includes multiple cells evenly distributed in an array. Each cell includes an upper plate, a middle plate, and two receiving sleeves. The middle plate is horizontally positioned, and a receiving sleeve is provided on each of its upper and lower sides. The receiving sleeves are open at both ends, and their sidewalls are curved. The small ends of the two receiving sleeves are fixedly connected to the end faces of the middle plate in the longitudinal direction, and the interiors of the two receiving sleeves are connected. An upper plate is fixedly connected to the upper end face of the large end of the upper receiving sleeve, and the upper receiving sleeve is connected to the lower receiving sleeve of its adjacent upper cell. The upper plate and the middle plate are fixedly connected between each pair of adjacent cells.

[0006] Furthermore, a large through hole is provided in the middle of the upper plate, and the large end of the upper receiving sleeve is connected to the large end of the lower receiving sleeve of the adjacent upper cell through the large through hole.

[0007] Furthermore, a small through hole is provided in the middle of the intermediate plate, and the small end of the upper receiving sleeve is connected to the small end of the lower receiving sleeve through the small through hole.

[0008] Furthermore, a base plate is fixedly attached to the lower end face of the sleeve below the bottommost cell, and the base plates are fixedly attached between every two adjacent cells.

[0009] Furthermore, the receiving sleeve is filled with impact-resistant material.

[0010] Furthermore, the cross-sectional shape of the receiving sleeve is an inverse cosine curve.

[0011] Furthermore, the inverse cosine curve of the upper receiving sleeve satisfies the following functional relationship.

[0012]

[0013] The inverse cosine curve of the lower receiving sleeve satisfies the following functional relationship

[0014]

[0015] In formulas (1) and (2), x∈[-b,b], a>0, b>0.

[0016] A method for fabricating a fillable zero Poisson's ratio impact-resistant structure includes the following steps:

[0017] Step 1: Draw the inverse cosine curve:

[0018] The inverse cosine curve of the upper support sleeve satisfies the following functional relationship

[0019]

[0020] The inverse cosine curve of the lower receiving sleeve satisfies the following functional relationship

[0021]

[0022] In formulas (1) and (2), x∈[-b,b], a>0, a is used to adjust the height of the cell, b>0, b is used to control the curvature of the surface in the cell;

[0023] The thickness of the upper plate and the middle plate is set to t1, the wall thickness of the receiving sleeve is t2, the inner radius of the large end of the receiving sleeve is R1, and the inner radius of the small end of the receiving sleeve is R2.

[0024] After drawing the inverse cosine curve, reserve a thickness of t1 at the large end of the inverse cosine curve of the upper receiving sleeve for the subsequent installation of the upper plate, and reserve a thickness of t1 at the small end of the inverse cosine curve of the upper receiving sleeve for the subsequent installation of the middle plate.

[0025] Step 2: Making the receiving sleeve: Rotate the two obtained inverse cosine curves 360 degrees along the y-axis to obtain the curved surfaces of the upper and lower receiving sleeves, and make two receiving sleeves respectively.

[0026] Step 3: Creating the cell: Install an upper plate at the large end of the upper receiving sleeve with a thickness of t1, and install an intermediate plate at the small end of the upper receiving sleeve with a thickness of t1. Then, coaxially fix the intermediate plate and the upper receiving sleeve and the upper plate above it to the small end of the lower receiving sleeve to obtain a complete cell.

[0027] Step 4: Arraying: Linearly array the cells to obtain the impact-resistant structure;

[0028] Step 5: Install a base plate: For impact-resistant structures that require filling, install a base plate at the large end of the receiving sleeve below the bottom cell to seal the bottom end of the impact-resistant structure, and then fill the receiving sleeve with impact-resistant material.

[0029] Furthermore, in step one, the inner radius R1 of the large end of the receiving sleeve and the inner radius R2 of the small end of the receiving sleeve satisfy R1 = R2 + 2b.

[0030] Furthermore, the upper plate, the middle plate, and the bottom plate are all square plates, and the width of the upper plate, the middle plate, and the bottom plate is L. Adjusting the value of parameter L can control the lateral length dimension of the cell, thereby adjusting the distance between two adjacent receiving sleeves in the array-backed impact-resistant structure.

[0031] The beneficial effects of this invention compared to the prior art are:

[0032] 1. The design of the anticosine surface gives the zero Poisson's ratio structure high stiffness, plateau stress, and good impact resistance and energy absorption capacity.

[0033] 2. The plateau stress of the structure was significantly improved by filling with shear-thickening gel, which further enhanced the impact resistance and energy absorption capacity of the anticosine surface structure.

[0034] 3. By using flexible materials as the matrix, the structure achieves high load-bearing capacity and impact resistance while also being recoverable and reusable. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the inverse cosine curve and reserved thickness of the upper supporting sleeve 2 in this invention;

[0036] Figure 2 This is a schematic diagram of the upper supporting sleeve 2 and the reserved thickness in this invention;

[0037] Figure 3 This is a schematic diagram of the structure of the upper supporting sleeve 2, the upper plate 1 and the middle plate 3 after assembly in this invention;

[0038] Figure 4 This is a schematic diagram of the inverse cosine curve of the lower receiving sleeve 2 in this invention;

[0039] Figure 5 This is a schematic diagram of the lower receiving sleeve 2 in this invention;

[0040] Figure 6 This is a schematic diagram of the structure of cell 4 in this invention;

[0041] Figure 7 This is a schematic diagram of the structure of the lowest-level cell 4 in this invention;

[0042] Figure 8 This is a schematic diagram of the overall structure of the present invention;

[0043] Figure 9 This is a schematic diagram of the shear-thickening gel filling process in this invention. Detailed Implementation

[0044] Specific implementation method one: Combining Figures 1 to 9 This embodiment describes a fillable zero Poisson's ratio impact-resistant structure comprising multiple cells 4 evenly distributed in an array. Each cell 4 includes an upper plate 1, a middle plate 3, and two receiving sleeves 2. The middle plate 3 is horizontally positioned, with a receiving sleeve 2 on each of its upper and lower sides. The receiving sleeves 2 are open at both ends, and their sidewalls are curved. The smaller ends of the two receiving sleeves 2 are fixedly connected to the end faces of the middle plate 3 along the longitudinal direction, and the interiors of the two receiving sleeves 2 are connected. The upper plate 1 is fixedly connected to the upper end face of the larger end of the upper receiving sleeve 2, and the upper receiving sleeve 2 is connected to the lower receiving sleeve 2 of its adjacent upper cell 4. The upper plate 1 and the middle plate 3 are fixedly connected between each pair of adjacent cells 4.

[0045] The structure is composed of an ordered array of cells 4, each cell being a surface obtained by rotating an inverse cosine curve. Two symmetrical receiving sleeves 2 are obtained by longitudinal mirroring. An upper plate 1 and a middle plate 3 are designed at the ends of the receiving sleeves 2 to ensure effective connection between the cells 4. By arranging the cells 4 in an orderly manner and enclosing the bottom layer of cells 4 (by adding a base plate 5), a complete inverse cosine surface zero Poisson's ratio structure can be obtained.

[0046] This invention designs an anticosine surface zero Poisson's ratio structure, which has high longitudinal load-bearing capacity and adds a fillable design. This means that in addition to the high impact resistance of the structure itself, the impact resistance of the structure can be further enhanced by filling it with other impact-resistant materials or structures.

[0047] Its longitudinally arranged curved surface design and the addition of transverse flat plates give the structure excellent load-bearing capacity. Furthermore, with its bottom sealed, the structure can serve as a carrier for other impact-resistant materials / structures. For example, filling the interior with shear-thickening fluid / gel can further enhance the structure's energy absorption capacity. The structural design allows for sealing at both the ends and middle of the cells, meaning the structure can not only be bottom-sealed but also have the flat plates moved upwards to achieve surface filling, partial filling, or full filling of shear-thickening fluid / gel or other impact-resistant materials / structures, offering strong design flexibility and programmability in impact resistance.

[0048] Specific Implementation Method Two: Combining Figures 1 to 9 In this embodiment, a large through hole 1-1 is provided in the middle of the upper plate 1. The large end of the upper receiving sleeve 2 is connected to the large end of the lower receiving sleeve 2 of the adjacent upper cell 4 through the large through hole 1-1. The undisclosed technical features in this embodiment are the same as those in specific embodiment one.

[0049] This design allows the lower cell 4 to be connected to the adjacent upper cell 4.

[0050] Specific implementation method three: Combining Figures 1 to 9 In this embodiment, a small through hole 3-1 is provided in the middle of the intermediate plate 3. The small end of the upper receiving sleeve 2 is connected to the small end of the lower receiving sleeve 2 through the small through hole 3-1. The undisclosed technical features in this embodiment are the same as those in specific embodiment two.

[0051] This design allows the upper receiving sleeve 2 and the lower receiving sleeve 2 inside cell 4 to be connected.

[0052] Specific implementation method four: Combination Figures 1 to 9 In this embodiment, a base plate 5 is fixedly connected to the lower end face of the sleeve 2 below the bottommost cell 4, and the base plates 5 are fixedly connected between every two adjacent cells 4. The undisclosed technical features in this embodiment are the same as in specific embodiment one.

[0053] For impact-resistant structures that require filling, this design involves adding a base plate 5 to the bottom of the structure, which allows the bottom of the structure to be sealed, and the structure can then serve as a carrier for supporting other impact-resistant materials / structures.

[0054] Specific Implementation Method Five: Combining Figures 1 to 9 This embodiment describes a method where the receiving sleeve 2 is filled with impact-resistant material. The undisclosed technical features in this embodiment are the same as in specific embodiment four.

[0055] The impact-resistant material can be a shear-thickening fluid / gel or other impact-resistant material / structure.

[0056] Specific Implementation Method Six: Combination Figures 1 to 9 This embodiment describes a receiving sleeve 2 with a cross-sectional shape that is an inverse cosine curve. Any undisclosed technical features in this embodiment are the same as in specific embodiment one.

[0057] Specific implementation method seven: Combining Figures 1 to 9 In this embodiment, the inverse cosine curve of the upper receiving sleeve 2 satisfies the following functional relationship.

[0058]

[0059] The inverse cosine curve of the lower sleeve 2 satisfies the following functional relationship

[0060]

[0061] In formulas (1) and (2), x∈[-b,b], a>0, b>0. The undisclosed technical features in this embodiment are the same as in specific embodiment six.

[0062] Specific implementation method eight: Combination Figures 1 to 9 This embodiment describes a method for manufacturing a fillable zero Poisson's ratio impact-resistant structure, which includes the following steps:

[0063] Step 1: Draw the inverse cosine curve:

[0064] The inverse cosine curve of the upper supporting sleeve 2 satisfies the following functional relationship

[0065]

[0066] The inverse cosine curve of the lower sleeve 2 satisfies the following functional relationship

[0067]

[0068] In formulas (1) and (2), x∈[-b,b], a>0, a is used to adjust the height of cell 4, b>0, b is used to control the curvature of the surface in cell 4;

[0069] The thickness of the upper plate 1 and the middle plate 3 are both set to t1, the wall thickness of the receiving sleeve 2 is t2, the inner radius of the large end of the receiving sleeve 2 is R1, and the inner radius of the small end of the receiving sleeve 2 is R2.

[0070] After drawing the inverse cosine curve, a thickness of t1 is reserved at the large end of the inverse cosine curve that receives the upper sleeve 2 for the subsequent installation of the upper plate 1, and a thickness of t1 is reserved at the small end of the inverse cosine curve that receives the upper sleeve 2 for the subsequent installation of the middle plate 3.

[0071] Step 2: Making the receiving sleeve: Rotate the two obtained inverse cosine curves 360 degrees along the y-axis to obtain the curved surfaces of the upper receiving sleeve 2 and the lower receiving sleeve 2, and make two receiving sleeves 2 respectively.

[0072] Step 3: Making the cell: Install the upper plate 1 at the position where the upper receiving sleeve 2 is reserved with a thickness of t1, and install the middle plate 3 at the position where the upper receiving sleeve 2 is reserved with a thickness of t1. Then, fix the middle plate 3 and the upper receiving sleeve 2 and the upper plate 1 on the lower receiving sleeve 2 coaxially to the small end of the lower receiving sleeve 2 to obtain the complete cell 4.

[0073] Step 4: Arraying: Linearly array the 4 cells to obtain the impact-resistant structure;

[0074] Step 5: Install base plate: For impact-resistant structures that require filling, install base plate 5 at the large end of the receiving sleeve 2 below the bottom cell 4 to seal the bottom end of the impact-resistant structure, and then fill the receiving sleeve 2 with impact-resistant material.

[0075] In this embodiment, the arrayed structure can be sealed off at any location where a plate is added, i.e., the pre-reserved holes on the plate are removed, making the structure a semi-closed structure to facilitate subsequent filling.

[0076] In this embodiment, the stability of structural deformation can be controlled by adjusting the relative magnitudes of parameters t1 and t2 in step one. When t2 is less than t1, the structural deformation is more stable.

[0077] To further enhance the impact resistance of the structure, other impact-resistant materials or structures can be filled into the structural cavities. For example, shear-thickening gels. Shear-thickening gels are typical strain rate-sensitive materials; during impact, they are sensitive to impact velocity, exhibiting a "stronger impact, stronger resistance" effect, making them highly suitable for impact-resistant environments. As mentioned earlier, by adjusting the closed state of the plate, various filling states of shear-thickening gels, such as surface filling, partial filling, and full filling, can be achieved.

[0078] Specific Implementation Method Nine: Combining Figures 1 to 9 In this embodiment, in step one, the inner radius R1 of the large end of the receiving sleeve 2 and the inner radius R2 of the small end of the receiving sleeve 2 satisfy R1 = R2 + 2b. The undisclosed technical features in this embodiment are the same as in specific embodiment eight.

[0079] Specific Implementation Method Ten: Combining Figures 1 to 9 In this embodiment, the upper plate 1, the middle plate 3, and the bottom plate 5 are all square plates, and the width of each plate is L. Adjusting the parameter L can control the lateral length of the cell 4, thereby adjusting the distance between two adjacent receiving sleeves 2 in the array's impact-resistant structure. The undisclosed technical features in this embodiment are the same as in specific embodiment eight.

[0080] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. 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. A fillable zero Poisson's ratio impact-resistant structure, characterized in that: It includes multiple cells (4) evenly distributed in an array. Each cell (4) includes an upper plate (1), a middle plate (3) and two receiving sleeves (2). The middle plate (3) is horizontally arranged. Each of the upper and lower sides of the middle plate (3) is provided with a receiving sleeve (2). The receiving sleeves (2) are open at both ends and the sidewalls of the receiving sleeves (2) are curved. The small ends of the two receiving sleeves (2) are fixed to the end face of the middle plate (3) in the longitudinal direction. The interiors of the two receiving sleeves (2) are connected. The upper plate (1) is fixed to the upper end face of the large end of the upper receiving sleeve (2). The upper receiving sleeve (2) is connected to the lower receiving sleeve (2) of its upper adjacent cell (4). The upper plate (1) and the middle plate (3) are fixed to each adjacent cell (4). The cross-sectional shape of the receiving sleeve (2) is an inverse cosine curve.

2. The fillable zero Poisson's ratio impact-resistant structure according to claim 1, characterized in that: The upper plate (1) has a large through hole (1-1) in the middle, and the large end of the upper receiving sleeve (2) is connected to the large end of the lower receiving sleeve (2) of the adjacent upper cell (4) through the large through hole (1-1).

3. The fillable zero Poisson's ratio impact-resistant structure according to claim 2, characterized in that: The middle plate (3) has a small through hole (3-1) in the middle, and the small end of the upper receiving sleeve (2) is connected to the small end of the lower receiving sleeve (2) through the small through hole (3-1).

4. The fillable zero Poisson's ratio impact-resistant structure according to claim 1, characterized in that: A base plate (5) is fixedly attached to the lower end face of the large end of the sleeve (2) below the bottom cell (4), and the base plate (5) is fixedly attached between each two adjacent cells (4).

5. The fillable zero Poisson's ratio impact-resistant structure according to claim 4, characterized in that: The receiving sleeve (2) is filled with impact-resistant material.

6. The fillable zero Poisson's ratio impact-resistant structure according to claim 1, characterized in that: The inverse cosine curve of the upper supporting sleeve (2) satisfies the following functional relationship （1） The inverse cosine curve of the lower supporting sleeve (2) satisfies the following functional relationship （2） In formulas (1) and (2), , >0, >0, Used to adjust the height of cell (4), >0, Used to regulate the curvature of the surface in cell (4).

7. A method for manufacturing a fillable zero Poisson's ratio impact-resistant structure according to any one of claims 1-6, characterized in that: The method includes the following steps: Step 1: Draw the inverse cosine curve: The inverse cosine curve of the upper supporting sleeve (2) satisfies the following functional relationship （1） The inverse cosine curve of the lower supporting sleeve (2) satisfies the following functional relationship （2） In formulas (1) and (2), , >0, Used to adjust the height of cell (4), >0, Used to regulate the curvature of the surface in cell (4); The thickness of the upper plate (1) and the middle plate (3) is set to t1, the wall thickness of the receiving sleeve (2) is t2, the inner radius of the large end of the receiving sleeve (2) is R1, and the inner radius of the small end of the receiving sleeve (2) is R2. After drawing the inverse cosine curve, a thickness of t1 is reserved at the large end of the inverse cosine curve of the upper receiving sleeve (2) for subsequent installation of the upper plate (1), and a thickness of t1 is reserved at the small end of the inverse cosine curve of the upper receiving sleeve (2) for subsequent installation of the middle plate (3). Step 2: Making the receiving sleeve: Rotate the two inverse cosine curves obtained by 360 degrees along the y-axis to obtain the curved surfaces of the upper receiving sleeve (2) and the lower receiving sleeve (2), and make two receiving sleeves (2) respectively. Step 3: Making the cell: Install an upper plate (1) at the large end of the upper receiving sleeve (2) with a thickness of t1 reserved, and install an intermediate plate (3) at the small end of the upper receiving sleeve (2) with a thickness of t1 reserved. Then, fix the intermediate plate (3) and the upper receiving sleeve (2) and the upper plate (1) on the small end of the lower receiving sleeve (2) coaxially to obtain the complete cell (4). Step 4: Arraying: Linearly array the cells (4) to obtain the impact-resistant structure; Step 5: Install base plate: For impact-resistant structures that need to be filled, install base plate (5) at the large end of the receiving sleeve (2) below the bottom cell (4) to close the bottom end of the impact-resistant structure, and then fill the receiving sleeve (2) with impact-resistant material.

8. The method for manufacturing a fillable zero Poisson's ratio impact-resistant structure according to claim 7, characterized in that: In step one, the inner radius R1 of the large end of the receiving sleeve (2) and the inner radius R2 of the small end of the receiving sleeve (2) satisfy R1 = R2 + 2b.

9. The method for manufacturing a fillable zero Poisson's ratio impact-resistant structure according to claim 7, characterized in that: The upper plate (1), the middle plate (3) and the bottom plate (5) are all square plates. The width of the upper plate (1), the middle plate (3) and the bottom plate (5) is L. Adjusting the value of parameter L can control the lateral length of cell (4), thereby adjusting the distance between two adjacent receiving sleeves (2) in the array-backed impact-resistant structure.

Images