A thermal protection structure based on shape memory material and an aircraft

Abstract

The application provides a heat protection structure based on a shape memory material and an aircraft, and relates to the technical field of aircraft protection, and the heat protection structure is applied to the aircraft, and the heat protection structure based on the shape memory material comprises a heat protection assembly, the heat protection assembly comprises a center piece and a plurality of cells arranged in the circumferential direction of the center piece, the plurality of cells are movably connected with the center piece, and each two adjacent cells in the plurality of cells are movably connected; wherein each cell is deformed or deformed to recover relative to the center piece after a set condition is met, so that the heat protection assembly is switched between a folded and contracted state and an unfolded state; and a telescopic rod, the heat protection assembly is movably connected with the aircraft through the telescopic rod. The application can provide better heat protection for the aircraft, and can also significantly improve the strength, rigidity and shock resistance of the heat protection assembly.

Description

Technical Field

[0001] This invention relates to the field of aircraft protection technology, and more specifically, to a thermal protection structure based on shape memory materials and an aircraft. Background Technology

[0002] With the development of aerospace technology, spacecraft are flying faster and faster, and operating environments are becoming increasingly harsh. Effective thermal protection structures are one of the key conditions to ensure the safe flight of spacecraft.

[0003] Existing thermal protection structures can generally be divided into three types: flexible thermal protection structures, rigid ceramic tile thermal protection structures, and metal thermal protection structures. Flexible thermal protection structures are a type of blanket-like heat protection structure with superior deformation capacity and features such as light weight and good thermal shock resistance, but they are difficult to withstand external impact loads. Rigid ceramic tile thermal protection structures and metal thermal protection structures have better thermal protection effects, but they are difficult to deform and cannot adapt to more complex environments. Summary of the Invention

[0004] The present invention aims to solve the problem that existing thermal protection structures are unable to simultaneously achieve both impact load resistance and deformation capacity.

[0005] To address the aforementioned problems, in a first aspect, the present invention provides a thermal protection structure based on shape memory materials, applied to aircraft, comprising:

[0006] A thermal protection assembly, comprising a central component and a plurality of cells arranged circumferentially along the central component, wherein the plurality of cells are movably connected to the central component and each pair of adjacent cells are movably connected to each other.

[0007] Each of the cells deforms or recovers from the central component after meeting the set conditions, so that the thermal protection assembly switches between a folded and contracted state and an unfolded state.

[0008] The thermal protection assembly is movably connected to the aircraft via the telescopic pole, so that when the thermal protection assembly is in the deployed state, it is aligned with sunlight at a set angle.

[0009] Optionally, the cell unit includes a folded active metamaterial part, a thermal protection part, a crease part, and a plurality of substrates distributed at intervals on one side of the thickness direction of the folded active metamaterial part. The thermal protection part is provided on at least two sides of the substrate in the thickness direction, and the crease part is provided at the adjacent position of every two adjacent substrates.

[0010] Optionally, the folded active metamaterial portion includes a core portion and a skin that uniformly wraps around the core portion, wherein the skin on at least one side of the core portion is connected to the substrate through the thermal protection portion.

[0011] Optionally, the core portion includes one or more of the following: concave hexagonal, star-shaped, double-arrow-shaped, four-ligament chiral, and six-ligament chiral honeycomb structures.

[0012] Optionally, the thermal protection portion includes a first thermal protection portion and a second thermal protection portion. The first thermal protection portion is disposed on the side of the substrate away from the folded active metamaterial portion. The second thermal protection portion includes a flexible thermal protection portion and a rigid thermal protection portion. The rigid thermal protection portion is used to connect the skin and the substrate and matches the shape and number of the substrate. The crease portion includes the flexible thermal protection portion.

[0013] Optionally, a crease is formed between the plurality of cells and the central member, and a crease is formed between each pair of adjacent cells. The crease portion of each cell includes a first crease portion and a plurality of second crease portions. The first crease portion is used for folding and unfolding between the cells, and the plurality of second crease portions are used for folding and unfolding within the cell.

[0014] Optionally, the first crease portion is inclined at a set angle along the circumference of the central member, and multiple second crease portions are provided, which are symmetrically distributed on both sides of the first crease portion with the first crease portion as the axis of symmetry, and the second crease portions are evenly spread outward in a radial pattern along the first crease portion.

[0015] Optionally, the material used to fabricate the folded active metamaterial includes shape memory polymers and / or shape memory polymer composites, wherein the plurality of cells are integrally printed, or each cell is individually printed, and each pair of adjacent cells is connected to a protrusion via a slide rail, and an elastic locking component is provided at the connection point to limit the relative movement of the two.

[0016] Optionally, the setting conditions include the temperature of the folded active metamaterial reaching the glass transition temperature. The setting conditions correspond to one or more of the setting driving methods, including thermal driving, electric driving, radio frequency driving, microwave driving, and optical driving.

[0017] This invention, by arranging multiple cells along the circumference of the central component and movably connecting these cells to the central component, and by movably connecting any two adjacent cells, allows each cell to synchronously deform and reverse-deform relative to the central component under predetermined conditions. For example, this can achieve convergence and unfolding, respectively. Correspondingly, the thermal protection component presents a folded / contracted state and an unfolded state. Combined with the telescopic rod, this meets the thermal protection requirements of the aircraft during on-orbit flight. On the ground or in off-orbit flight, the thermal protection component can deform to a converged state, while upon reaching the designated orbit, it can deform to an unfolded state to meet deformation requirements in complex environments. Furthermore, the unfolded thermal protection component can directly face sunlight, providing better thermal protection for the aircraft. Because the multiple cells in the thermal protection component are arranged along the central component, they are tightly connected around it, significantly improving the strength, stiffness, and shock resistance of the thermal protection component.

[0018] Secondly, the present invention also provides an aircraft including a thermal protection structure based on shape memory material as described in any of the above embodiments.

[0019] The aircraft provided by this invention has the same beneficial effects as the thermal protection structure compared to the prior art, and will not be repeated here. Attached Figure Description

[0020] Figure 1 An unfolded view of the thermal protection structure of the aircraft in an embodiment of the present invention is shown;

[0021] Figure 2 A folding diagram of the thermal protection structure of the aircraft in an embodiment of the present invention is shown;

[0022] Figure 3 A side view of the thermal protection structure of an aircraft in an embodiment of the present invention is shown;

[0023] Figure 4 This invention illustrates a separate unfolded configuration of a thermal protection structure based on shape memory materials in an embodiment of the present invention. Figure 1 ;

[0024] Figure 5 This invention illustrates a separate unfolded configuration of a thermal protection structure based on shape memory materials in an embodiment of the present invention. Figure 2 ;

[0025] Figure 6 This invention illustrates a separate unfolded configuration of a thermal protection structure based on shape memory materials in an embodiment of the present invention. Figure 3 ;

[0026] Figure 7An intermediate state diagram of the folded thermal protection structure based on shape memory material in an embodiment of the present invention is shown;

[0027] Figure 8 This invention illustrates a single folded configuration of a thermal protection structure based on shape memory materials, as shown in an embodiment of the invention. Figure 2 ;

[0028] Figure 9 A rear view of a thermal protection structure based on shape memory material in an embodiment of the present invention is shown;

[0029] Figure 10 This diagram illustrates the state of the thermal protection structure based on shape memory material facing sunlight in an embodiment of the present invention.

[0030] Figure 11 A unit cell diagram of a thermal protection structure based on shape memory material in an embodiment of the present invention is shown;

[0031] Figure 12 A schematic diagram of the structure of the folded active metamaterial section in an embodiment of the present invention is shown;

[0032] Figure 13 This shows a front view of the unfolded thermal protection structure based on shape memory material in an embodiment of the present invention;

[0033] Figure 14 A schematic diagram of a six-ligament chiral honeycomb structure is shown in an embodiment of the present invention.

[0034] Figure 15 This diagram illustrates a double-arrow honeycomb structure as shown in an embodiment of the present invention.

[0035] Figure 16 This diagram illustrates a structure in which the sandwich structure is a concave hexagonal honeycomb structure in an embodiment of the present invention.

[0036] Figure 17 This diagram illustrates a four-ligament chiral honeycomb structure as the sandwich structure in an embodiment of the present invention.

[0037] Figure 18 This diagram illustrates a star-shaped honeycomb structure as shown in an embodiment of the present invention.

[0038] Figure 19 A separate folding diagram of the thermal protection structure in an embodiment of the present invention is shown;

[0039] Figure 20 A schematic diagram of the connections between cells in an embodiment of the present invention is shown;

[0040] Figure 21 A schematic diagram of the cell connection positions in an embodiment of the present invention is shown. Figure 1;

[0041] Figure 22 A schematic diagram of the cell connection positions in an embodiment of the present invention is shown. Figure 2 ;

[0042] Figure 23 A schematic diagram of the pin assembly in an embodiment of the present invention is shown.

[0043] Explanation of reference numerals in the attached drawings: 1. Aircraft; 2. Thermal protection component; 3. Telescopic rod; 4. Ball hinge; 5. Protrusion; 6. Cell; 7. Central component; 8. Thermal protection section; 9. Substrate; 10. Crease section; 101. First crease section; 102. Second crease section; 11. Folded active metamaterial section; 111. Skin; 112. Sandwich section; 12. Solar panel; 13. Elastic locking component; 131. Elastic pin; 1311. Pin section; 1312. Base; 1313. Spring; 132. Pin hole; 14. Slide rail; 15. Flexible thermal protection section; 16. Rigid thermal protection section. Detailed Implementation

[0044] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0045] It should be noted that relational terms such as "first" and "second" in this invention are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0046] In the description of this specification, references to terms such as "embodiment," "one embodiment," and "one implementation" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or implementation is included in at least one embodiment or illustrative implementation of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or implementation. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or implementations.

[0047] Reference Figure 1 , Figure 2 and Figure 3 As shown, this embodiment of the invention proposes a thermal protection structure based on shape memory material, applied to an aircraft 1. The thermal protection structure based on shape memory material includes: a thermal protection component 2, the thermal protection component 2 including a central component 7 and a plurality of cells 6 arranged circumferentially along the central component 7, the plurality of cells 6 being movably connected to the central component 7, and each pair of adjacent cells 6 being movably connected.

[0048] For example, the thermal protection component 2 includes six cells 6 and a central element 7, which appears in the form of a plate and includes a central plate, with multiple cells 6 arranged in an array around the central plate.

[0049] Each of the cell units 6 deforms or recovers from deformation relative to the central component 7 after meeting the set conditions, so that the thermal protection component 2 switches between a folded and contracted state and an unfolded state.

[0050] Since the plurality of cells 6 are movably connected to the central member 7, and each pair of adjacent cells 6 are movably connected, the cells 6 can fold, contract, and unfold relative to the central member 7.

[0051] For example, the thermal protection component 2 may be made of a shape memory polymer material to meet the requirements for deformation and deformation recovery.

[0052] For example, the spacecraft could be a satellite platform or a space station, and the thermal protection structure could be installed on the outer bulkhead of the satellite platform / space station.

[0053] Specifically, the set conditions may be that the cell 6 is equipped with a mechanical drive component (such as hydraulic drive) to drive the cell 6 to fold, shrink and unfold relative to the central component 7, or the cell 6 may be made of shape memory polymer composite material, so as to realize deformation and shape memory recovery at a certain temperature, and complete the switching of the thermal protection component 2 between the folded and unfolded state.

[0054] The telescopic pole 3 is used to connect the thermal protection component 2 to the aircraft 1 so that when the thermal protection component 2 is in the deployed state, it is aligned with the sunlight at a set angle.

[0055] The thermal protection component 2 is movably connected to the aircraft 1 via the telescopic rod 3, thereby adjusting the telescopic length of the telescopic rod 3. This allows the protective component in the deployed state to face the sunlight at a set angle, such as the deployed plane of cell 6 being perpendicular to the sunlight, thus providing better thermal protection for the aircraft 1 during its on-orbit flight.

[0056] In practical application, this embodiment utilizes multiple cells 6 arranged circumferentially along the central component 7, with each cell 6 movably connected to the central component 7. Furthermore, each adjacent cell 6 is movably connected to the central component 7. This allows each cell 6 to simultaneously deform and reverse-deform relative to the central component 7 under certain conditions, such as converging and unfolding. Correspondingly, the thermal protection component 2 presents a folded / contracted state and an unfolded state. Combined with the telescopic rod 3, this meets the thermal protection requirements of the aircraft 1 during on-orbit flight. On the ground or during off-orbit flight, the thermal protection component 2 can deform to a converging state. When the aircraft reaches its designated orbit, it can be driven to deform to an unfolded state to meet deformation requirements in complex environments. The unfolded thermal protection component 2 can directly face sunlight, providing better thermal protection for the aircraft 1. Moreover, because the multiple cells 6 in the thermal protection component 2 are arranged along the central component 7, they are tightly connected around the central component 7, significantly improving the strength, stiffness, and seismic resistance of the thermal protection component 2.

[0057] like Figure 4 , Figure 5 and Figure 6 and Figure 9 As shown, in an optional embodiment of the present invention, the telescopic rod 3 is provided in two sets. One set of telescopic rods 3 is fixedly installed on the outer wall of the aircraft 1, and its extended end is connected to the central member 7 through a ball hinge 4. The other set of telescopic rods 3 is hingedly installed on the outer wall of the aircraft 1, and its extended end is connected to the central member 7 through a ball hinge 4, so that the control end of the aircraft 1 can adjust the angle between the thermal protection component and the sunlight when it is deployed.

[0058] like Figure 11 and Figure 12 As shown, in an optional embodiment of the present invention, the cell 6 includes a folded active metamaterial portion 11, a thermal protection portion 8, a crease portion 10, and a plurality of substrates 9 spaced apart on one side of the thickness direction of the folded active metamaterial portion 11. The thermal protection portion 8 is provided on at least two sides of the substrate 9 in the thickness direction, and the crease portion 10 is provided at the adjacent position of each two adjacent substrates 9.

[0059] Specifically, the thermal protection part 8 is designed to reduce the impact of high temperature or other heat sources on the substrate 9 and the folded active metamaterial part 11. It is located at least on both sides of the substrate 9 and can provide all-round thermal protection, gradually reducing the heat from the sun-facing side. The substrate 9 serves as the main support part of the cell 6.

[0060] like Figure 12As shown, in an optional embodiment of the present invention, the folded active metamaterial part 11 includes a core part 112 and a skin 111 that uniformly wraps the core part 112. The skin 111 on at least one side of the core part 112 is connected to the substrate 9 through the thermal protection part.

[0061] Specifically, the foldable active metamaterial part 11 can be made of shape memory polymer material to meet the requirements of deformation and deformation recovery. The sandwich panel is placed inside the skin 111 to protect the sandwich panel, so that the sandwich panel and the skin 111 are as a whole to meet the requirements of the thermal protection structure on the track.

[0062] like Figure 14 , Figure 15 , Figure 16 , Figure 17 and Figure 18 As shown, as an optional embodiment of the present invention, the core portion 112 includes one or more of the following: concave hexagonal, star-shaped, double-arrow-shaped, four-ligament chiral, and six-ligament chiral honeycomb structures.

[0063] Specifically, the various types of honeycomb structures in the sandwich core 112 can be selected in practice. These types of honeycomb structures not only improve the buffering and shock absorption capacity of the cell 6, thereby improving the overall stiffness and strength of the thermal protection structure, but also further improve the heat absorption capacity, thereby improving the thermal protection capacity.

[0064] like Figure 11 and Figure 12 As shown, in an optional embodiment of the present invention, the thermal protection part 8 includes a first thermal protection part and a second thermal protection part. The first thermal protection part is disposed on the side of the substrate 9 away from the folded active metamaterial part 11. The second thermal protection part includes a flexible thermal protection part 15 and a rigid thermal protection part 16. The rigid thermal protection part 16 is used to connect the skin 111 and the substrate 9 and matches the shape and number of the substrate 9. The crease part 10 includes the flexible thermal protection part 15. Of course, the crease part 10 can also be made of other materials (such as flexible materials) to effectively resist folding damage. The flexible thermal protection part 15 is disposed on the side of the crease part 10 away from the folded active metamaterial part 11. The substrate 9 provides the main mechanical support.

[0065] Specifically, the first thermal protection part is located on the side of the substrate 9 away from the folded active metamaterial part 11, that is, the side away from the aircraft 1 when unfolded. The rigid thermal protection part 16 of the second thermal protection part is located between the skin 111 and the substrate 9. The flexible protection part can be bent to adapt to the crease and play a role in thermal protection. The rigid protection part matches each substrate 9, that is, the number and area of ​​the two are equal.

[0066] Cell 6 can also serve as the radar antenna of spacecraft 1. As spacecraft 1 operates in orbit, the radar antenna unfolds, and the substrate 9 provides a platform for the radar antenna.

[0067] The above-mentioned thermal protection structure can block heat when the cell 6 it is located in unfolds, and then absorb heat through the folded active metamaterial part 11, so as to achieve the layer-by-layer decomposition of heat and thus provide better thermal protection for the aircraft 1.

[0068] like Figure 6 , Figure 7 , Figure 8 , Figure 13 and Figure 19 As shown, in an optional embodiment of the present invention, a crease is formed between the plurality of cells 6 and the center member 7, and a crease is formed between each pair of adjacent cells 6. The crease portion 10 of each cell 6 includes a first crease portion 101 and a plurality of second crease portions 102. The first crease portion 101 is used for folding and unfolding between the cells 6, and the plurality of second crease portions 102 are used for folding and unfolding within the cell 6.

[0069] In practical application, this embodiment provides at least one first fold portion 101 within the cell 6. The first fold portion 101 divides the cell 6 equally, meaning the substrate 9 is distributed along the first fold portion 101 and the second fold portion 102. The first fold portion 101 and the second fold portion 102 are folds between the substrate 9. These folds facilitate the folding, contraction, and unfolding within the cell 6 (the folding active metamaterial portion 11 folds, contracts, and unfolds along with the substrate 9). The folds between the cell 6 facilitate the folding, contraction, and unfolding between the cell 6. During the folding deformation process, as the cell 6 folds and contracts along the folds and each cell 6 along... As the central component 7 folds, the folding and contraction of the cell 6 along the first crease 101 mainly occurs. After the folding and contraction reaches a certain extent, not only does the folding and contraction between cells 6 along the crease and the folding and contraction within the cell 6 along the first crease 101 occur, but also the folding and contraction within the cell 6 along the second crease 102 occurs, ultimately forming a folded and contracted state. The unfolding process is the reverse process. This origami-like method (folding or unfolding), along with the deformation of the cell 6 along the central component 7, causes deformation within the cell 6 and deformation between cells 6, which can enable the heat protection structure to achieve a large storage ratio.

[0070] like Figure 13As shown, in an optional embodiment of the present invention, the first crease portion 101 is inclined at a set angle along the circumference of the center member 7, and a plurality of second crease portions 102 are provided and symmetrically distributed on both sides of the first crease portion 101 with the first crease portion 101 as the axis of symmetry, and the second crease portions 102 are evenly spread outward in a radial pattern along the first crease portion 101.

[0071] In practical application, the first crease 101 and the second crease 102 are creases within cell 6. During the folding, shrinking, or unfolding process, cell 6 folds along the center member 7, shrinks within cell 6, and folds and shrinks between cells 6. The folding and shrinking process is as follows: each cell 6 simultaneously gathers along the crease between every two cells 6, and the cell 6 folds along the crease with the center member 7. Simultaneously, the first crease 101 within each cell 6 shrinks and gathers. Since the first crease 101 is tilted at a set angle along the circumference of the center member 7, the gathering reduces the distance from the center member 7 to the edge of cell 6. When the gathering reaches a set radius (the minimum distance from the center member 7 to the edge of cell 6), each cell 6 further moves along the second crease 102 in the same direction (e.g., counterclockwise or clockwise, etc.). Figure 7 The folding process (clockwise from a top-down view) involves folding cell 6 together along the first crease 101, with cells 6 fitting together. The outermost part of each cell 6 fits into the next outermost part of the cell 6 in the folding direction, ultimately making the outermost part of cell 6 form a certain angle (e.g., perpendicular) with the center member 7. The unfolding process is the reverse of this process and will not be described here. For the folding process, please refer to [link to folding process]. Figure 6 , Figure 7 and Figure 8 .

[0072] like Figure 13 , Figure 19 and Figure 20 As shown, as an optional embodiment of the present invention, the folded active metamaterial part 11 is made of a shape memory polymer and / or a shape memory polymer composite material, wherein the plurality of cells 6 are integrally printed, or each cell 6 is individually printed, and each pair of adjacent cells 6 is connected to the protrusion 5 by a slide rail 14, and an elastic locking component 13 for limiting the relative movement of the two is provided at the connection.

[0073] Specifically, in one embodiment, shape memory composite material is printed using 4D printing technology to form a folded active metamaterial part 11. The resin used in the composite material is an epoxy-based shape memory polymer or a cyanate-based shape memory polymer. The reinforcing elements in the composite material are carbon fibers, nanoparticles, carbon nanotubes grafted with carbon fibers, chopped fibers, etc. The matrix 9 can be made of C / C composite material, rigid fiber thermal protection material, or high-performance ceramic foam, etc. The matrix 9 can be pasted or printed on the surface of the folded active metamaterial part 11. The thermal protection part can be made of rigid fiber thermal protection material and / or high-performance ceramics, etc. The flexible thermal protection part 15 uses SiOC aerogel / flexible ceramic fiber composite material. The rigid thermal protection material can be C / C composite material or rigid fiber thermal protection material. Each cell 6 is integrally printed to form a thermal protection structure.

[0074] like Figure 21 , Figure 22 and Figure 23 As shown, in another embodiment, only the folded active metamaterial part 11 is integrally printed. The printed folded active metamaterial part 11 is fixed to the thermal protection part, the crease part 10, and the substrate 9 by a setting method, such as gluing or heat fusion. In this way, each individual cell 6 is isolated and connected to the protrusion 5 by a slide rail 14. The slide rail 14 and the protrusion 5 are respectively set at the connection of two adjacent cells 6, and the slide rail 14 and the protrusion 5 engage and can adapt to folding. During the folding process, the elastic locking component 13 can limit the relative movement of each two adjacent cells 6. The elastic locking component 13 includes a solid... A base 1312 is fixed at a certain part of cell 6 (such as the side edge of the folded active metamaterial part 11). The base 1312 can be right-angled. The bottom of the right angle is connected to cell 6, and the top is connected to a pin part 1311 by a spring 1313. The base 1312, spring 1313 and pin part 1311 constitute an elastic pin 131, which can adapt to folding and limit and lock cell 6. In addition, the elastic pin 131 cooperates with the pin hole 132. The elastic pin 131 and the pin hole 132 are respectively set on two adjacent cells 6. Furthermore, a strong magnetic layer or a fastener can be provided in the pin hole 132 to strengthen and fix the pin part 1311.

[0075] The integrated printing method provided above, or the method of printing part first and then fixing the other parts, realizes the folding connection between cells 6. The printing method forms the connection within cells 6, which can be selected for practical applications and ensures the realization of the thermal protection structure.

[0076] The set conditions include the temperature of the folded active metamaterial part 11 reaching the glass transition temperature. The set conditions correspond to one or more of the set driving methods, including thermal driving, electric driving, radio frequency driving, microwave driving, and optical driving.

[0077] Specifically, the glass transition temperature is the temperature at which the shape memory polymer and / or the shape memory polymer composite material undergoes a phase transition. In practice, this temperature can be determined based on the actual material, thereby achieving the temperature at which deformation or deformation recovery is realized. That is, the folded active metamaterial part 11 is kept in a folded and contracted state, and heating is stopped when the temperature of the folded active metamaterial part 11 reaches the glass transition temperature and then changes to an unfolded state. Alternatively, it is kept in an unfolded state, and heating is stopped when the temperature of the folded active metamaterial part 11 reaches the glass transition temperature and then changes to a folded and contracted state.

[0078] For example, if thermal drive is used, a resistive thin-film heater is attached to the lower surface of the thermal protection structure (the side of cell 6 closest to aircraft 1).

[0079] If an electric drive method is used, the shape memory composite material should be doped with one or more of the following conductive reinforcing phases: single-walled carbon nanotubes, multi-walled carbon nanotubes, graphene, carbon black, carbon nanopaper, carbon nanofibers, chopped carbon fibers, continuous carbon fibers, or mixed particles, and an external power source should be connected to the doped phases to form a circuit.

[0080] If microwave-driven methods are used, shape memory polymer composite materials should be doped with nanoparticles such as carbon nanotubes, graphene oxide, and silicon carbide.

[0081] If radio frequency (RF) driving is used, the shape memory polymer composite material should be doped with RF-sensitive particles such as carbon nanotubes.

[0082] If a light-driven method is used, optical fibers or other materials should be embedded in the shape memory polymer composite material.

[0083] If a combined driving method is adopted, the reinforcement doped in the shape memory polymer composite material shall include two or more combinations of doped materials (from the electric driving method to the optical driving method).

[0084] The driver program is:

[0085] If a heat-driven method is used: When the attached thin-film heater is energized, heating stops once the temperature reaches above the glass transition temperature, as the heat-protective structure deforms from a folded / contracted state to an unfolded state. Power can be supplied via solar panel 12.

[0086] If an electric drive method is used: when electricity is applied to the shape memory composite material, the heat protection structure deforms from the folded and contracted state to the unfolded state after the temperature reaches above the glass transition temperature, and then the heating stops.

[0087] If a microwave-driven method is used: a microwave field is applied to the shape memory composite material, and when the temperature reaches above the glass transition temperature, the thermal protection structure deforms from a folded and contracted state to an unfolded state and then the heating stops.

[0088] If radio frequency (RF) driving is used: an RF field is applied to the shape memory composite material. When the temperature reaches above the glass transition temperature, the thermal protection structure deforms from the folded and contracted state to the unfolded state and then the heating stops.

[0089] If a light-driven method is used: a light field is applied to the shape memory composite material, and when the temperature reaches above the glass transition temperature, the heat protection structure deforms from the folded and contracted state to the unfolded state and then the heating stops.

[0090] If a combined driving method is used: apply the corresponding excitation to the combined driving method selected for the shape memory composite material, and stop heating after the temperature reaches above the glass transition temperature, the thermal protection structure deforms from the folded and contracted state to the unfolded state.

[0091] The abundant shape memory materials and corresponding driving methods in the above embodiments can be selected for practical applications, providing reliable protection for the folding, contraction, and unfolding of the thermal protection structure of the aircraft 1.

[0092] like Figure 10 As shown, the present invention also provides an aircraft 1, including the thermal protection structure as described in any of the above embodiments. The aircraft 1 may be a satellite or a space station, etc. By configuring this thermal protection structure based on shape memory material, the aircraft 1 has good thermal protection function.

[0093] The specific implementation method of this embodiment can be referred to the corresponding implementation method described above, and will not be described again here.

[0094] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features of the invention herein.

[0095] While the present invention has been disclosed above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and all such changes and modifications will fall within the scope of protection of the present invention.

Claims

1. A thermal protection structure based on shape memory material, characterized in that, Applied to aircraft (1), including: A thermal protection component (2) includes a central component (7) and a plurality of cells (6) arranged circumferentially along the central component (7). The plurality of cells (6) are movably connected to the central component (7), and each pair of adjacent cells (6) are movably connected to each other. Each of the cells (6) deforms or recovers from deformation relative to the central member (7) after meeting the set conditions, so that the thermal protection assembly (2) switches between a folded and contracted state and an unfolded state. Telescopic rod (3), the thermal protection component (2) is movably connected to the aircraft (1) through the telescopic rod (3) so that when the thermal protection component (2) is in the deployed state, it is aligned with the sunlight at a set angle; The cell (6) includes a folded active metamaterial part (11), a thermal protection part (8), a crease part (10), and a plurality of substrates (9) spaced apart on one side of the thickness direction of the folded active metamaterial part (11). The thermal protection part (8) is provided on at least two sides of the thickness direction of the substrate (9). The crease part (10) is provided at the adjacent position of each pair of adjacent substrates (9). A crease is formed between the plurality of cells (6) and the center member (7), and a crease is formed between each pair of adjacent cells (6). The crease portion (10) of each cell (6) includes a first crease portion (101) and a plurality of second crease portions (102). The first crease portion (101) is inclined at a set angle along the circumference of the center member (7). There are multiple second crease portions (102), which are symmetrically distributed on both sides of the first crease portion (101) with the first crease portion (101) as the axis of symmetry. The second crease portions (102) are evenly spread outward in a radial pattern along the first crease portion (101).

2. The thermal protection structure based on shape memory material according to claim 1, characterized in that, The folded active metamaterial part (11) includes a core part (112) and a skin (111) that uniformly wraps the core part (112). The skin (111) on at least one side of the core part (112) is connected to the substrate (9) through the thermal protection part (8).

3. The thermal protection structure based on shape memory material according to claim 2, characterized in that, The core portion (112) includes one or more of the following: concave hexagonal, star-shaped, double-arrow-shaped, four-ligament chiral, and six-ligament chiral honeycomb structures.

4. The thermal protection structure based on shape memory material according to claim 2, characterized in that, The thermal protection part (8) includes a first thermal protection part and a second thermal protection part. The first thermal protection part is disposed on the side of the substrate (9) away from the folded active metamaterial part (11). The second thermal protection part includes a flexible thermal protection part (15) and a rigid thermal protection part (16). The rigid thermal protection part (16) is used to connect the skin (111) and the substrate (9) and matches the shape and number of the substrate (9). The crease part (10) includes the flexible thermal protection part (15).

5. The thermal protection structure based on shape memory material according to any one of claims 1-4, characterized in that, The folded active metamaterial part (11) is made of a shape memory polymer and / or a shape memory polymer composite material, wherein a plurality of cells (6) are integrally printed, or each cell (6) is individually printed, and each pair of adjacent cells (6) is connected to a protrusion (5) by a slide rail (14), and an elastic locking component (13) is provided at the connection to limit the relative movement of the two.

6. The thermal protection structure based on shape memory material according to any one of claims 1-4, characterized in that, The set conditions include the temperature of the folded active metamaterial part (11) reaching the glass transition temperature. The set conditions correspond to one or more of the set driving methods, including thermal driving, electric driving, radio frequency driving, microwave driving and optical driving.

7. An aircraft, characterized in that, Including the thermal protection structure based on shape memory material as described in any one of claims 1-6.

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