Support structure, support system with variable Poisson's ratio and preparation method thereof

Abstract

The present invention relates to the field of 3D material printing technology, and in particular to a support structure, a support system with a variable Poisson's ratio, and a preparation method thereof. The support structure includes: a first force-bearing seat, a second force-bearing seat, a first support member, and a second support member; the first support member is close to each other in its first position and the second position of the second support member, and is away from each other at both ends. Under the first condition, the lateral stiffness of the first support member is greater than that of the second support member, and under the second condition, the lateral stiffness of the first support member is less than that of the second support member. The present application provides a support structure, a support system with a variable Poisson's ratio, and a preparation method thereof. According to the material properties of the first support member and the second support member arranged in the above-mentioned structure, they can be compressed under different conditions and protrude in different directions. They can be used as a component of a support system that regulates the Poisson's ratio online according to the conditions, so that it has the ability to convert the Poisson's ratio into positive and negative.

Description

Technical Field

[0001] The present invention relates to the technical field of 3D material printing, and in particular to a support structure, a support system with a variable Poisson's ratio, and a preparation method thereof. Background Art

[0002] When a material is subjected to axial tension or compression, it not only deforms axially but also expands and contracts transversely. The ratio of the transverse strain to the longitudinal strain is defined as the Poisson's ratio. Conventional materials have a positive Poisson's ratio, meaning they contract axially when stretched and expand transversely when compressed. However, through appropriate design of the material's three-dimensional structure, a negative Poisson's ratio can be achieved. This means that when subjected to axial tension, the material expands transversely instead of contracting. This characteristic is also known as the "tensile expansion" effect. This negative Poisson's ratio imparts advantages over conventional materials. For example, it can improve the material's shear modulus, resilience, and fracture resistance. Furthermore, negative Poisson's ratio materials broaden their application. For example, in medicine, negative Poisson's ratio materials can be delivered in a contracted state to the site of a blood clot. Then, through axial tension, they expand transversely, propping up the blood vessel and resolving the blockage. Negative Poisson's ratio materials have been researched and applied in areas such as wave manipulation, vibration suppression, and multimode configuration. In fact, the above materials can be classified as "metamaterials". Although the definition of metamaterials has not yet been unified, the academic community generally believes that metamaterials have two key characteristics: they can exhibit unconventional properties different from traditional materials; and these properties originate from the spatial structure of the metamaterial, rather than the material itself that constitutes it.

[0003] Metamaterials can also exhibit another unique property: variable stiffness. When a structure is deformed axially by tension or compression, the ratio of the axial load to the deformation is the stiffness. Most structures maintain constant stiffness when the deformation is not too large. However, the stiffness can be varied through appropriate design of the material structure. Common stiffness variation properties include stiffness hardening, where the larger the deformation, the greater the increase in load required to produce a unit deformation, resulting in a "harder" structure; and stiffness softening, where the larger the deformation, the smaller the increase in load required to produce a unit deformation, resulting in a "softer" structure. Variable stiffness properties have broad application prospects and can be used for wave manipulation, resonance suppression, load adaptation, and more. In particular, bistable properties, where the force provided by the structure has a definite upper limit, can flexibly absorb large impacts and exhibit excellent cushioning and energy absorption properties.

[0004] Currently, researchers have proposed a variety of metamaterial structures with negative Poisson's ratios and variable stiffness. However, these structures have some shortcomings. Most structures have fixed properties after manufacture, making them difficult to adjust dynamically, and their posture cannot be dynamically adjusted according to conditions. For example, a support system made of negative Poisson's ratio materials always has a negative Poisson's ratio, and the posture of the supporting structure that constitutes the support system cannot be dynamically adjusted according to conditions. This limits its application scenarios. Therefore, there is an urgent need for a support structure that can form a support system with online control of the Poisson's ratio according to conditions. Summary of the Invention

[0005] The present invention provides a support structure, a support system with a variable Poisson's ratio, and a preparation method thereof, to address the defects in the prior art that, after the support structure is manufactured, its posture cannot be dynamically adjusted according to conditions, and the support system composed of the support structure cannot online adjust the Poisson's ratio according to conditions, and does not have the ability to convert the Poisson's ratio between positive and negative.

[0006] The present invention provides a support structure comprising:

[0007] The first force bearing seat;

[0008] The second force bearing seat;

[0009] a first support member, wherein one end of the first support member is connected to the first force-bearing seat, and the other end of the first support member is connected to the second force-bearing seat;

[0010] a second support member, one end of the second support member being connected to the first force-bearing seat, and the other end of the second support member being connected to the second force-bearing seat;

[0011] wherein the first support member is connected to the second support member at a first position and the second support member at a second position, so that the first support member and the second support member are close to each other in the first position and the second position, one end of the first support member and one end of the second support member are far away from each other, and the other end of the first support member and the other end of the second support member are far away from each other, the first position is between one end and the other end of the first support member, and the second position is between one end and the other end of the second support member;

[0012] Under the first condition, the stiffness of the first support member in the direction perpendicular to the line connecting the first force-bearing seat and the second force-bearing seat is greater than that of the second support member; under the second condition, the stiffness of the first support member in the direction perpendicular to the line connecting the first force-bearing seat and the second force-bearing seat is less than that of the second support member.

[0013] According to a support structure provided by the present invention, the first support member includes: a polylactic acid support member;

[0014] The second support member includes: a thermoplastic polyurethane elastic support member;

[0015] At a first temperature, the polylactic acid support member has a stiffness greater than that of the thermoplastic polyurethane elastic support member in a direction perpendicular to a line connecting the first force-bearing seat and the second force-bearing seat;

[0016] At the second temperature, the thermoplastic polyurethane elastic support member has a stiffness greater than that of the polylactic acid support member in a direction perpendicular to a line connecting the first force-bearing seat and the second force-bearing seat.

[0017] A supporting structure provided according to the present invention further includes:

[0018] a first connecting portion, the first connecting portion being disposed at the first position;

[0019] The second connecting portion is provided at the second position, and the second supporting member at the second position is connected to the first supporting member at the first position through the second connecting portion and the first connecting portion.

[0020] According to a support structure provided by the present invention, the first connecting portion includes: a first protrusion between one end and the other end of the first support member and extending toward and close to the second support member;

[0021] The first connection portion includes a first protrusion between one end and the other end of the first support member and extending toward the second support member.

[0022] According to a support structure provided by the present invention, the first support member is constrained by the first force-bearing seat, the second force-bearing seat and the first connecting portion to form an arc-shaped structure;

[0023] The second supporting member is constrained by the first force-bearing seat, the second force-bearing seat and the second connecting portion to form an arc-shaped structure.

[0024] According to a support structure provided by the present invention, the first support member is constrained by the first force-bearing seat, the second force-bearing seat and the first connecting portion to present a sinusoidal curve structure;

[0025] The second supporting member is constrained by the first force-bearing seat, the second force-bearing seat and the second connecting portion to present a sinusoidal curve structure.

[0026] The present invention also provides a support system with a variable Poisson's ratio, comprising:

[0027] A supporting structure capable of protruding in different directions under pressure under different conditions, and having an accommodation space formed inside the supporting structure;

[0028] A plurality of supporting bodies are provided in the accommodating space.

[0029] According to a variable Poisson's ratio support system provided by the present invention, under a first condition, the Poisson's ratio of the variable Poisson's ratio support system is less than 0; under a second condition, the Poisson's ratio of the variable Poisson's ratio support system is greater than 0.

[0030] According to a variable Poisson's ratio support system provided by the present invention, at a first temperature, the Poisson's ratio of the variable Poisson's ratio support system is less than 0; at a second temperature, the Poisson's ratio of the variable Poisson's ratio support system is greater than 0.

[0031] The present invention also provides a method for preparing a support system with a variable Poisson's ratio, comprising:

[0032] By using 3D printing technology, the support system with a variable Poisson's ratio as in the embodiment of the present invention is integrally printed; or,

[0033] The support structure and the plurality of support bodies in the support system with a variable Poisson's ratio as in the embodiment of the present invention are prepared separately and assembled.

[0034] The present invention provides a support structure, which includes: a first force-bearing seat, a second force-bearing seat, a first support member and a second support member; the first force-bearing seat and the second force-bearing seat have the function of fixing and positioning the end of the first support member and the end of the second support member, the first support member is close to each other in its first position and the second position of the second support member, and is away from each other at both ends, under the first condition, the lateral stiffness of the first support member is greater than that of the second support member, and under the second condition, the lateral stiffness of the first support member is less than that of the second support member. The support structure provided by the present application, according to the first support member and the second support member arranged in the above structure and the material properties of the first support member and the second support member, can be compressed under different conditions and protrude in different directions, and can be used as a component of a support system that adjusts the Poisson's ratio online according to the conditions, so that it has the ability to convert the Poisson's ratio into positive and negative.

[0035] Furthermore, the present invention provides a support system with a variable Poisson's ratio, which adopts a support structure that can protrude in different directions under pressure under different conditions. Therefore, under different conditions, it will exhibit different Poisson's ratio characteristics, realizing the conditional regulation of the structural Poisson's ratio and having the ability to convert the Poisson's ratio into positive and negative.

[0036] Furthermore, the present invention provides a method for preparing a support system with a variable Poisson's ratio, which adopts technologies such as 3D printing or machining, and can directly print and produce the support system with a variable Poisson's ratio in the above-mentioned embodiment of the present invention. It can also prepare the support structure and multiple support bodies separately and then assemble them. The preparation process is flexible, fast and highly reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0038] Figure 1 is a schematic structural diagram of a support structure in a free state provided in one embodiment of the present invention;

[0039] Figure 2 is a schematic structural diagram of a support structure provided in one embodiment of the present invention under a first condition, when the first force-bearing seat and the second force-bearing seat are under pressure;

[0040] Figure 3 It is a structural schematic diagram of a support system with a variable Poisson's ratio provided in one embodiment of the present invention.

[0041] Reference numerals:

[0042] 1: First force-bearing seat; 2: Second force-bearing seat; 3: First support member; 4: Second support member; 5: First connecting portion; 6: Second connecting portion; 7: Support body. DETAILED DESCRIPTION

[0043] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0044] In the description of the embodiments of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as limiting the embodiments of the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance.

[0045] In the description of the embodiments of the present invention, it should be noted that, unless otherwise specified or limited, the terms "connected" and "connection" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; and direct connections or indirect connections through an intermediary. Those skilled in the art will understand the specific meanings of the above terms in the embodiments of the present invention based on the specific circumstances.

[0046] In the embodiments of the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, a first feature being "above," "above," or "above" a second feature may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. A first feature being "below," "below," or "below" a second feature may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0047] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0048] The following combination Figure 1-Figure 2 The present invention describes a support structure comprising a first force-bearing seat 1 , a second force-bearing seat 2 , a first support member 3 and a second support member 4 .

[0049] One end of the first support member 3 is connected to the first force-bearing seat 1, and the other end of the first support member 3 is connected to the second force-bearing seat 2; one end of the second support member 4 is connected to the first force-bearing seat 1, and the other end of the second support member 4 is connected to the second force-bearing seat 2.

[0050] Specifically, the first force-bearing seat 1 and the second force-bearing seat 2 serve as force-bearing components, respectively. On the one hand, they can withstand the extrusion force or the tensile force, and on the other hand, they have the function of fixing and positioning the ends of the first support member 3 and the second support member 4. Preferably, the first force-bearing seat 1 and the second force-bearing seat 2 can adopt a flat plate structure.

[0051] The first support member 3 is connected to the second support member 4 at the first position, so that the first support member 3 and the second support member 4 are close to each other in the first position and the second position, one end of the first support member 3 and one end of the second support member 4 are far away from each other, and the other end of the first support member 3 and the other end of the second support member 4 are far away from each other. The first position is located between one end and the other end of the first support member 3, and the second position is located between one end and the other end of the second support member 4. The first position of the first support member 3 is connected to the second position of the second support member 4, so that the first position and the second position are close to each other, and the positions of the two ends of the first support member 3 and the second support member 4 are far away from each other. The first position is located in the middle of the first support member 3, and the second position is located in the middle of the second support member 4. The connection between the first support member 3 and the second support member 4 forms a structure that is wide at both ends and narrow in the middle. The structural diagram of the structure in the free state (that is, when no force is applied to the first force-bearing seat 1 and the second force-bearing seat 2) is as shown in FIG. Figure 1 shown.

[0052] Under the first condition, the first support member 3 has a stiffness greater than that of the second support member 4 in the direction perpendicular to the line connecting the first force-bearing seat 1 and the second force-bearing seat 2; under the second condition, the first support member 3 has a stiffness less than that of the second support member 4 in the direction perpendicular to the line connecting the first force-bearing seat 1 and the second force-bearing seat 2. It should be understood that when the first force-bearing seat 1 and the second force-bearing seat 2 are subjected to force, Figure 1 In the illustrated structure, a vertical force is applied to the first and second force-bearing seats 1 and 2. Under the first and second conditions, the stiffness relationship between the first and second support members 3 and 4 in a direction perpendicular to the line connecting the first and second force-bearing seats 1 and 2 changes. In other words, the lateral stiffness relationship between the first and second support members 3 and 4 changes. The first and second conditions can vary depending on the actual application environment, the properties of the materials used for the first and second support members 3 and 4, and the shape and size relationship of the first and second support members 3 and 4. These conditions can include temperature, humidity, and irradiation intensity, among others. The following embodiments illustrate temperature as the only condition.

[0053] In one feasible implementation: under the first condition, when the first force-bearing seat 1 and the second force-bearing seat 2 are compressed, the degree of lateral protrusion of the first support member 3 and the second support member 4 will increase accordingly, but the first support member 3 is connected and constrained at the first position and the second support member 4 at the second position. Since the first support member 3 and the second support member 4 have the same shape and size, and the Young's modulus of the material of the first support member 3 is larger, the lateral stiffness of the first support member 3 at the connection is greater than that of the second support member 4. Therefore, the first support member 3 plays a leading role, forcing the second support member 4 to protrude in the opposite direction, that is, Figure 2The overall structure shown here protrudes to the right. Conversely, under the second condition, since the first and second support members 3 and 4 have the same shape and size, and the Young's modulus of the first support member 3 is smaller than that of the second support member 4, the lateral stiffness of the second support member 4 at the connection is greater than that of the first support member 3. Therefore, the second support member 4 plays a dominant role, forcing the first support member 3 to protrude, and the overall structure protrudes to the left.

[0054] In another feasible implementation, under both the first and second conditions, the Young's modulus of the material of the first support member 3 is greater than that of the second support member 4. However, under the first condition, the Young's modulus of the material of the first support member 3 is significantly greater, while under the second condition, while still greater, the difference is comparable. In this case, simply reducing the thickness of the first support member 3 appropriately can achieve the same effect of greater lateral stiffness of the first support member 3 at the connection location under the first condition, while achieving the opposite effect under the second condition.

[0055] From this, it can be seen that the first support member 3 and the second support member 4 arranged according to the above-mentioned structure and the material properties of the first support member 3 and the second support member 4 will protrude in different directions under pressure under different conditions, and can be used as a component of a support system that can online adjust the Poisson's ratio according to the conditions, so that it has the ability to convert the Poisson's ratio into positive and negative.

[0056] The present invention provides a support structure, which includes: a first force-bearing seat 1, a second force-bearing seat 2, a first support member 3 and a second support member 4; the first force-bearing seat 1 and the second force-bearing seat 2 have the function of fixing and positioning the end of the first support member 3 and the end of the second support member 4, the first support member 3 is close to each other in its first position and the second position of the second support member 4, and is away from each other at both ends, under a first condition, the stiffness of the first support member 3 along the direction perpendicular to the line connecting the first force-bearing seat 1 and the second force-bearing seat 2 is greater than that of the second support member 4, and under a second condition, the stiffness of the first support member 3 along the direction perpendicular to the line connecting the first force-bearing seat 1 and the second force-bearing seat 2 is less than that of the second support member 4. The support structure provided by the present application, according to the first support member 3 and the second support member 4 arranged in the above structure and the material properties of the first support member 3 and the second support member 4, can be compressed under different conditions and protrude in different directions, and can be used as a component of a support system that adjusts the Poisson's ratio online according to conditions, so that it has the ability to convert the Poisson's ratio into positive and negative.

[0057] In one embodiment of the present invention, the first support member 3 includes: a polylactic acid support member; the second support member 4 includes: a thermoplastic polyurethane elastic support member. In the above selection, ensure that at the first temperature, the stiffness (i.e., lateral stiffness) of the polylactic acid support member in the direction perpendicular to the line connecting the first force-bearing seat 1 and the second force-bearing seat 2 is greater than that of the thermoplastic polyurethane elastic support member; ensure that at the second temperature, the stiffness (i.e., lateral stiffness) of the thermoplastic polyurethane elastic support member in the direction perpendicular to the line connecting the first force-bearing seat 1 and the second force-bearing seat 2 is greater than that of the polylactic acid support member. Specifically, the first support member 3 is made of polylactic acid (full name: polylactic acid; abbreviated: PLA) material, and the second support member 4 is made of thermoplastic polyurethane elastomer rubber (full name: Thermoplastic polyurethanes; abbreviated: TPU) material. For example: the first support member 3 and the second support member 4 have the same shape and size. The first temperature is 25°C. At this temperature, the Young's modulus of polylactic acid (PLA) is greater than that of thermoplastic polyurethane (TPU). Therefore, the lateral stiffness of the PLA support member is greater than that of the TPU elastic support member. The second temperature is 80°C. At this temperature, PLA undergoes a glass transition, and its Young's modulus rapidly decreases, falling below that of TPU. Therefore, the lateral stiffness of the PLA support member is less than that of the TPU elastic support member. Of course, other materials with the above properties can also be used, such as polyurethane (PU) and silicone. The Young's modulus of silicone is sensitive to humidity. Therefore, below a certain humidity, the Young's modulus of silicone rubber is high. Above a certain humidity, silicone rubber absorbs water and softens rapidly, while polyurethane has a high Young's modulus. Alternatively, soft rubber and silicone can be used. Silicone ages and hardens more quickly after UV exposure. Therefore, the Young's modulus of soft rubber is high before irradiation, while that of silicone rubber is high after irradiation. However, it is worth noting that this method is one-way and difficult to recover after irradiation.

[0058] In one embodiment of the present invention, the support structure further includes: a first connecting portion 5 and a second connecting portion 6. The first connecting portion 5 is located at a first position; the second connecting portion 6 is located at a second position; and the second support member 4 is connected to the first support member 3 at the first position through the second connecting portion 6 and the first connecting portion 5 at the second position. In this embodiment, the first connecting portion 5 is located at the first position of the first support member 3 and is made of the same material as the first support member 3; the second connecting portion 6 is located at the second position of the second support member 4 and is made of the same material as the second support member 4. By connecting the first connecting portion 5 and the second connecting portion 6, the first support member 3 at the first position is connected to the second support member 4 at the second position, thereby constraining each other. Under different conditions, the first support member 3 and the second support member 4 respectively dominate the deformation.

[0059] In one embodiment of the present invention, the first connecting portion 5 includes: a first protrusion extending between one end and the other end of the first support member 3 toward the second support member 4; the first connecting portion 5 includes: a first protrusion extending between one end and the other end of the first support member 3 toward the second support member 4. Preferably, the first protrusion is located at the geometric center of the first support member 3, and its protruding direction is perpendicular to the first support member 3; the second protrusion is located at the geometric center of the second support member 4, and its protruding direction is perpendicular to the second support member 4. The first protrusion is connected to the second protrusion to ensure that in the connected position, the first support member 3 and the second support member 4 are arranged close to each other, while at the two end positions, the first support member 3 and the second support member 4 are arranged away from each other.

[0060] In one embodiment of the present invention, the first support member 3 is constrained by the first force-bearing seat 1, the second force-bearing seat 2, and the first connecting portion 5 to form an arc-shaped structure; the second support member 4 is constrained by the first force-bearing seat 1, the second force-bearing seat 2, and the second connecting portion 6 to form an arc-shaped structure. In this embodiment, under the connection constraints of the first connecting portion 5 and the second connecting portion 6, the first position of the first support member 3 is adjacent to the second position of the second support member 4 and is connected thereto, and both are in an arc-shaped structure. When a force is applied to the first force-bearing seat 1 and the second force-bearing seat 2, the arc-shaped structures of the first support member 3 and the second support member 4 will change.

[0061] In one embodiment of the present invention, the first support member 3 is constrained by the first force-bearing seat 1, the second force-bearing seat 2 and the first connecting portion 5, and is in a sinusoidal structure; the second support member 4 is constrained by the first force-bearing seat 1, the second force-bearing seat 2 and the second connecting portion 6, and is in a sinusoidal structure. In this embodiment, when no force is applied to the first force-bearing seat 1 and the second force-bearing seat 2, due to the constraints and limitations of the first connecting portion 5 and the second connecting portion 6, the first support member 3 and the second support member 4 are in a sinusoidal structure, and their protruding ends are close to each other. When force is applied to the first force-bearing seat 1 and the second force-bearing seat 2, the curved structures of the first support member 3 and the second support member 4 may change. Of course, according to actual needs, the curved structures of the first support member 3 and the second support member 4 may also be curved structures of other shapes.

[0062] The following combination Figure 3 The present invention provides a support system with a variable Poisson's ratio, which includes a support structure and a plurality of support bodies 7 .

[0063] The support structure can protrude in different directions when subjected to pressure under different conditions, and an accommodation space is formed inside the support structure; the support body 7 is disposed in the accommodation space.

[0064] Specifically, the support structure is located between the first force-bearing seat 1 and the second force-bearing seat 2. The first force-bearing seat 1 and the second force-bearing seat 2 bear extrusion force or tensile force and can force the support structure to deform. Based on the description of the above embodiment, the support structure presents the characteristic of protruding in different directions under different conditions. The support structure in this embodiment. The accommodating space formed inside the support structure is filled with a support body 7. The support body 7 acts as a loose support member in the accommodating space, which provides a function of strengthening or weakening rigidity when the support structure is compressed and deformed, which is specifically described in the following embodiments.

[0065] It can be understood that the support structure used in the variable Poisson's ratio support system can be the support structure in the above embodiment of the present invention, and one or more support structures are used to form an accommodating space for accommodating the support body.

[0066] It should be understood that the variable Poisson's ratio support system in this embodiment includes one or more support structures. These can be two, forming a two-dimensional support system, or three or more, forming a three-dimensional support system. An appropriate number of support structures can be designed and arranged according to actual needs. When only one support structure is used, it can be a three-dimensional columnar structure with a housing space formed within the columnar structure for accommodating the support body.

[0067] The present invention provides a support system with a variable Poisson's ratio, which adopts a support structure that can protrude in different directions under pressure under different conditions. Therefore, under different conditions, it will exhibit different Poisson's ratio characteristics, realizing the conditional regulation of the structural Poisson's ratio and having the ability to convert the Poisson's ratio into positive and negative.

[0068] In one embodiment of the present invention, under a first condition, the Poisson's ratio of the variable Poisson's ratio support system is less than 0; under a second condition, the Poisson's ratio of the variable Poisson's ratio support system is greater than 0. In this embodiment, the support body 7 can be made of materials such as TPU, PLA, ABS resin, or nylon. Preferably, the first condition in this embodiment is at a first temperature, and the second condition is at a second temperature. That is, at the first temperature, the Poisson's ratio of the variable Poisson's ratio support system is less than 0; at the second temperature, the Poisson's ratio of the variable Poisson's ratio support system is greater than 0. At the first temperature, the variable Poisson's ratio support system exhibits a negative Poisson's ratio characteristic. Increased deformation causes the structure to contract laterally, resulting in a tighter interior, thus exhibiting a stiffness-hardening characteristic. At the second temperature, the variable Poisson's ratio support system exhibits a positive Poisson's ratio characteristic. Increased deformation causes the structure to expand laterally, resulting in a looser interior, thus exhibiting a stiffness-softening characteristic. Thus, this embodiment achieves switching between stiffness-softening and stiffness-hardening characteristics based on changing conditions.

[0069] In one embodiment of the present invention, Figure 3 As shown, the support body 7 can adopt a two-dimensional structure or a three-dimensional structure. Preferably, the support body 7 in this embodiment adopts a cylindrical structure, and a plurality of support bodies 7 with the above cylindrical structure can be filled in the accommodation space of the support system. Preferably, five support bodies 7 of appropriate volume are filled in the accommodation space. Of course, the number of support bodies 7 arranged can be adjusted accordingly according to the volume of the support body 7 and the accommodation space. The present invention is not limited to the implementation method of the above embodiment.

[0070] The present invention also provides a method for preparing a support system with a variable Poisson's ratio. The method for preparing a support system with a variable Poisson's ratio comprises the following steps:

[0071] By using 3D printing technology, a support system with a variable Poisson's ratio as in the above embodiment of the present invention is printed as a whole; or, a support structure and multiple support bodies 7 in the support system with a variable Poisson's ratio as in the above embodiment of the present invention are prepared separately and assembled.

[0072] Specifically, the variable Poisson's ratio support system in the above embodiment of the present invention is implemented using 3D printing technology. It can be printed as a whole according to the above structure, or the support structure and support body 7 can be prepared or printed separately and then assembled to form the variable Poisson's ratio support system. If silicone material is used, it can be cured in a mold.

[0073] The present invention provides a method for preparing a support system with a variable Poisson's ratio, which adopts technologies such as 3D printing or machining, and can directly print and produce the support system with a variable Poisson's ratio in the above-mentioned embodiment of the present invention. It can also prepare the support structure and multiple support bodies 7 separately and then assemble them. The preparation process is flexible, fast and highly reliable.

[0074] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in one location or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of the present embodiment. Persons of ordinary skill in the art will be able to understand and implement the present invention without inventive effort.

[0075] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A support system with a variable Poisson's ratio, characterized in that: include: A supporting structure capable of protruding in different directions under pressure under different conditions, and having an accommodation space formed inside the supporting structure; a plurality of supporting bodies, wherein the supporting bodies are arranged in the accommodating space; The supporting structure comprises: The first force bearing seat; The second force bearing seat; a first support member, wherein one end of the first support member is connected to the first force-bearing seat, and the other end of the first support member is connected to the second force-bearing seat; a second support member, one end of the second support member being connected to the first force-bearing seat, and the other end of the second support member being connected to the second force-bearing seat; wherein the first support member is connected to the second support member at a first position and the second support member at a second position, so that the first support member and the second support member are close to each other in the first position and the second position, one end of the first support member and one end of the second support member are far away from each other, and the other end of the first support member and the other end of the second support member are far away from each other, the first position is between one end and the other end of the first support member, and the second position is between one end and the other end of the second support member; Under the first condition, the stiffness of the first support member in the direction perpendicular to the line connecting the first force-bearing seat and the second force-bearing seat is greater than that of the second support member; under the second condition, the stiffness of the first support member in the direction perpendicular to the line connecting the first force-bearing seat and the second force-bearing seat is less than that of the second support member.

2. The variable Poisson's ratio support system according to claim 1, characterized in that: The first support member includes: a polylactic acid support member; The second support member includes: a thermoplastic polyurethane elastic support member; At a first temperature, the polylactic acid support member has a stiffness greater than that of the thermoplastic polyurethane elastic support member in a direction perpendicular to a line connecting the first force-bearing seat and the second force-bearing seat; At the second temperature, the thermoplastic polyurethane elastic support member has a stiffness greater than that of the polylactic acid support member in a direction perpendicular to a line connecting the first force-bearing seat and the second force-bearing seat.

3. The variable Poisson's ratio support system according to claim 1, characterized in that: Also includes: a first connecting portion, the first connecting portion being disposed at the first position; The second connecting portion is provided at the second position, and the second supporting member at the second position is connected to the first supporting member at the first position through the second connecting portion and the first connecting portion.

4. The variable Poisson's ratio support system according to claim 3, characterized in that: The first connection portion includes a first protrusion between one end and the other end of the first support member and extending toward the second support member.

5. The variable Poisson's ratio support system according to claim 3 or 4, characterized in that: The first support member is constrained by the first force-bearing seat, the second force-bearing seat and the first connecting portion to form an arc-shaped structure; The second supporting member is constrained by the first force-bearing seat, the second force-bearing seat and the second connecting portion to form an arc-shaped structure.

6. The variable Poisson's ratio support system according to claim 5, characterized in that: The first support member is constrained by the first force-bearing seat, the second force-bearing seat and the first connecting portion to present a sinusoidal curve structure; The second supporting member is constrained by the first force-bearing seat, the second force-bearing seat and the second connecting portion to present a sinusoidal curve structure.

7. The variable Poisson's ratio support system according to claim 1, characterized in that: Under the first condition, the Poisson's ratio of the variable Poisson's ratio support system is less than 0; Under the second condition, the Poisson's ratio of the variable Poisson's ratio support system is greater than zero.

8. The variable Poisson's ratio support system according to claim 7, characterized in that: At a first temperature, the variable Poisson's ratio support system has a Poisson's ratio of less than 0; At the second temperature, the variable Poisson's ratio support system has a Poisson's ratio greater than zero.

9. A method for preparing a support system with a variable Poisson's ratio, characterized in that: include: By 3D printing technology, the support system with a variable Poisson's ratio as claimed in any one of claims 1 to 8 is integrally printed; or, The support structure and the plurality of support bodies in the support system with a variable Poisson's ratio according to any one of claims 1 to 8 are prepared separately and assembled.

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