A space debris protection structure and design method

Abstract

The present invention relates to a space debris protection structure and design method, which belongs to the field of space debris protection technology, and solves the problem that the spacecraft protection structure in the prior art has a large uplink volume and can only protect millimeter-level space debris. A space debris protection structure includes a mesh protection layer, a wave impedance protection layer, an energy-containing protection layer, an energy-absorbing protection layer, and a sandwich structure; the mesh protection layer, the wave impedance protection layer, the energy-containing protection layer, and the energy-absorbing protection layer are arranged in sequence from the outside to the inside along the impact direction of the space debris; and the protection layers are connected by a sandwich structure. A protection structure is provided that can meet the uplink constraint and protect large-sized space debris.

Description

Technical Field

[0001] The present invention relates to the field of space debris protection technology, and in particular to a space debris protection structure and a design method. Background Art

[0002] In recent years, with the rise of global commercial spaceflight and the intensive implementation of low-orbit Internet constellation plans, the number and growth rate of space debris in orbit have increased significantly, resulting in a significant increase in the probability of spacecraft in orbit being hit by debris, and the safety of the space environment faces new challenges. According to the current growth trend of space debris, in a few years, 3 to 4 spacecraft will fail each year due to debris impact.

[0003] It is estimated that in recent years, there are 900,000 centimeter-sized debris in the near-Earth orbit. However, due to the limitations of technology level, launch cost, uplink mass, volume and other factors, the current spacecraft protection structure can only protect millimeter-sized space debris and can only observe and track some centimeter-sized space debris, which cannot meet the current spacecraft protection needs. There is no spacing between the protective layers in the protective structures of patents CN102490912A, CN107140238A, and CN115817861A, which makes it impossible to reduce the impact energy of space debris by expanding the debris cloud, limiting the protective capability of the protective structure; the spacing between the protective layers in the protective structures of patents CN102514737A and CN105109709A is fixed, resulting in a large upward size and volume, limiting the number of protective layers of the protective structure; the protective structures of patents CN111152942A and CN114455099A achieve the spacing between the protective layers through inflation, which requires the design of an inflation device and a sealing structure, and has a complex structure. At the same time, the structure can only protect against one impact of space debris. After the impact, the protective capability is greatly or completely lost due to the loss of airtightness; the protective structure of patent CN116062191A achieves the spacing between the protective layers through electromechanical drive, which requires a motor to be implemented and the corresponding mechanical structure to be designed, and has a complex structure and a heavy device.

[0004] Therefore, it is necessary to design a protective structure that can both meet the uplink constraints and protect against large-sized space debris. Summary of the invention

[0005] In view of the above analysis, an embodiment of the present invention aims to provide a space debris protection structure and a design method, so as to reduce the uplink size of the protection structure and enhance the ability of the spacecraft to protect against hypervelocity impacts of large-sized space debris.

[0006] On the one hand, an embodiment of the present invention provides a space debris protection structure, including a mesh protection layer, a wave impedance protection layer, an energy-containing protection layer, an energy-absorbing protection layer, and a sandwich structure;

[0007] The mesh protection layer, wave impedance protection layer, energy-containing protection layer and energy-absorbing protection layer are arranged in sequence from outside to inside along the impact direction of space debris; and each protection layer is connected by a sandwich structure.

[0008] Furthermore, the debris protection structure includes two usage states:

[0009] State 1: folded state, during the ascent of the spacecraft, the sandwich structure is in a compressed state;

[0010] State 2: Deployment state: after the spacecraft reaches orbit, the sandwich structure is deployed along the direction of the space debris impact.

[0011] Furthermore, the mesh protective layer is one of aluminum alloy wire mesh, alloy steel wire mesh, and titanium alloy wire mesh.

[0012] Furthermore, the wave impedance protection layer is composed of three high-strength alloys or fiber materials arranged in a density gradient.

[0013] Specifically, the high-strength alloy is one or more of titanium alloy, aluminum alloy, and magnesium alloy, and the fiber material is one or more of polyimide fiber, silicon carbide fiber, basalt fiber, Kevlar fiber, carbon fiber, and PBO fiber.

[0014] Preferably, the energetic protective layer is composed of energetic materials, and the energetic material components are polytetrafluoroethylene / aluminum or aluminum / nickel

[0015] Preferably, the energy absorbing protective layer is an aramid fiber cloth filled with a shear thickening liquid.

[0016] On the other hand, the present invention also provides a method for designing a space debris protection structure, which is used for designing the space debris protection structure, and comprises the following steps:

[0017] S1. Input the orbit information of the spacecraft and obtain the impact conditions of the space debris under the orbit according to the space debris simulation software;

[0018] S2. Determine the design plan of the protection structure, and determine the number, size, thickness and spacing of each type of protection layer based on the constraints including uplink mass, size, volume, protection area and space debris impact conditions;

[0019] S3, establish a numerical simulation model and obtain simulation results. If the simulation result shows that it cannot provide effective protection, return to S2, optimize and determine the protection structure design scheme. If the simulation result shows that it can provide effective protection, proceed to the next step S4;

[0020] S4. Determine the ground test plan. If the ground test verification capability cannot meet the impact conditions, then establish equivalent impact conditions that meet the ground test verification capability based on the principle of equivalent damage effect; if the ground test verification capability meets the impact conditions, conduct the test according to the actual impact conditions;

[0021] S5. Conduct ground verification tests, prepare various types of protective layers and sandwich structures, establish a ground verification test system according to the design plan and impact conditions, and conduct ground verification tests;

[0022] S6. Determine the test results and the effect of the protective structure. If the protective structure can effectively protect against debris impact, the design scheme is feasible. If the protective structure cannot effectively protect against debris impact, analyze the cause of the failure. If it is a problem with the protective structure design scheme, return to step S2 to optimize and determine the protective structure design scheme. If it is a problem with the ground test scheme, return to step S4 to optimize and determine the ground test scheme.

[0023] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0024] 1. The present invention effectively improves the ability of spacecraft to protect against hypervelocity impacts of large-sized space debris by rationally designing and combining protective layers with different functions.

[0025] 2. The present invention adopts a sandwich structure to connect protective layers with different functions, so as to adjust the distance between each protective layer; when the sandwich structure is folded, the upward size and volume are greatly reduced; after the sandwich structure is unfolded, the intervals between each protective layer can be used to effectively reduce the impact energy of space debris by expanding the debris cloud; compared with conventional protective structures, the upward size and volume of the protective structure are greatly reduced while the protective capability is improved.

[0026] 3. The present invention determines the size of the protection target and the main parameters of the protection structure according to the protection requirements of space debris, and realizes the reliability verification of the space debris protection structure through a design method combining numerical simulation with ground verification tests.

[0027] 4. The present invention can adjust the thickness, area and number of layers of each protective layer according to the uplink weight, size requirements and the distribution information of the debris size on the track, and is flexibly applicable to the protection of space debris of various sizes.

[0028] In the present invention, the above-mentioned technical solutions can also be combined with each other to achieve more preferred combination solutions. Other features and advantages of the present invention will be described in the subsequent description, and some advantages can become obvious from the description, or can be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained through the contents particularly pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The drawings are only for the purpose of illustrating particular embodiments and are not to be considered limiting of the present invention. Like reference symbols denote like components throughout the drawings.

[0030] Figure 1 It is a state where the space debris protection structure is deployed;

[0031] Figure 2 It is a folded state of the space debris protection structure;

[0032] Figure 3 It is a schematic diagram of a design method for a space debris protection structure.

[0033] Reference numerals:

[0034] 1-mesh protection layer; 2-wave impedance protection layer; 3-energy-containing protection layer; 4-energy-absorbing protection layer; 5-sandwich structure; 6-heating plate. DETAILED DESCRIPTION

[0035] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0036] Limited by factors such as technological level, launch cost, uplink mass and volume, the current spacecraft protection structure can only protect millimeter-level space debris, and can only observe and track some centimeter-level space debris. In order to improve the protection capability, a multi-layer protection structure is designed to increase the uplink size and volume and limit the number of protection layers of the protection structure. It is very necessary to design a protection structure that can meet the uplink constraints and protect against large-sized space debris.

[0037] A specific embodiment of the present invention discloses a space debris protection structure, such as Figure 1 , 2 shown.

[0038] It includes a mesh protective layer, a wave impedance protective layer, an energetic protective layer, an energy absorbing protective layer, a sandwich structure and a heating plate; the mesh protective layer, the wave impedance protective layer, the energetic protective layer and the energy absorbing protective layer are arranged from outside to inside along the impact direction of space debris; the protective layers are connected by a sandwich structure, and a heating plate is attached to the surface of the sandwich structure.

[0039] Specifically, the sandwich structure is made of shape memory polymer material, which can be a commercially available material, such as a polyurethane composite system, polyester, polyolefin or epoxy system polymer, which has a shape memory effect and can perform folding and autonomous memory unfolding actions at a set temperature.

[0040] Exemplarily, the heating plate has a resistance wire inside, which is connected to a DC power supply inside the spacecraft through a wire. When the power supply is energized to the heating plate, the resistance wire generates heat to increase the temperature of the heating plate and heat the sandwich structure.

[0041] In one possible design, the mesh protective layer is one of aluminum alloy wire mesh, alloy steel wire mesh, and titanium alloy wire mesh; metal materials commonly used in aerospace engineering are used, and the advantage of the light weight of the mesh structure is utilized. The thickness of the mesh protective layer is designed according to the size of the fragments. The thickness of the mesh protective layer is greater than 1 / 8 of the diameter of the fragments, and preferably greater than 1 times the diameter of the fragments, so as to achieve a balance between the protection capability and the weight of the protective layer; the mesh protective layer has the ability to break up large-sized space debris and reduce the kinetic energy of space debris. The space debris forms a primary debris cloud after passing through the mesh protective layer; under the same surface density conditions, the mesh protective layer has the characteristics of more overlapping layers and greater thickness in local positions compared to conventional plate-shaped protective screens, thereby increasing the shock wave period when space debris collides and achieving the purpose of increasing the force of breaking space debris; at the same time, the mesh protective layer produces fewer secondary fragments after being impacted, the debris cloud is more dispersed, and the damage effect on the subsequent protective layer is lower.

[0042] In a possible design, the wave impedance protection layer is composed of three high-strength alloys or fiber materials arranged in a density gradient; the high-strength alloy is one or more of titanium alloy, aluminum alloy, and magnesium alloy, and the fiber material is a space debris protection material with good performance such as polyimide fiber, silicon carbide fiber, basalt fiber, Kevlar fiber, carbon fiber, PBO fiber, etc.; the wave impedance protection layer has the ability to further break up space debris and convert the kinetic energy of space debris into internal energy, and the primary debris cloud forms a secondary debris cloud after passing through the wave impedance protection layer; the wave impedance protection layer changes the propagation path and internal energy conversion efficiency of the shock wave generated by the impact of space debris in the protection layer through the density gradient characteristics, and at the same time increases the diffusion area of ​​the debris cloud and reduces the damage effect on the rear protection screen;

[0043] Furthermore, due to the existence of the sandwich structure, there is a gap between the wave impedance protection layer and the energetic protection layer. The gap distance allows the debris cloud passing through the wave impedance protection layer to be fully expanded, thereby further increasing the area of ​​the debris cloud impacting the energetic layer, and can fully utilize the energy release effect of subsequent energetic materials to reduce the kinetic energy of the debris or vaporize the debris.

[0044] In a possible design, the energetic protective layer is made of an energetic material with the composition of polytetrafluoroethylene / aluminum or aluminum / nickel; the energy density released by the reaction of the two energetic materials, the reaction temperature generated and the structural strength are balanced, which can meet the design requirements of the energetic protective layer of the present invention; the energetic protective layer has the ability to significantly reduce the kinetic energy of space debris, promote phase change of fragments, and reduce the number of secondary fragments, and the secondary debris cloud forms a tertiary debris cloud after passing through the energetic protective layer; the energetic material is sufficiently insensitive under quasi-static or static loads, and can undergo an impact detonation reaction under high-speed impact to release a large amount of energy, thereby forming a reverse impulse on the fragments to reduce the kinetic energy of the space debris, and at the same time generate high temperature and high pressure to promote phase change of fragments and reduce the number of secondary fragments.

[0045] In one possible design, the energy-absorbing protective layer is an aramid fiber cloth filled with a shear-thickening liquid; the aramid fiber cloth filled with the shear-thickening liquid can absorb rapid impact energy based on the special rheological properties of the shear-thickening liquid, effectively improve the energy absorption of the material, and has a high tensile elastic modulus; exemplarily, the shear-thickening liquid is composed of a dispersed phase and a dispersion medium, which can be a nano-SiO2 / PEG dispersion system; the energy-absorbing protective layer has the ability to absorb and transform the kinetic energy of space debris and intercept space debris, and the tertiary debris cloud forms millimeter-scale fragments that pose no threat to spacecraft after passing through the energy-absorbing protective layer; the energy-absorbing protective layer has high strength, high toughness, and high viscosity characteristics, and the shear-thickening liquid filled inside can increase the interaction force between material particles as the shear force generated by the impact of space debris increases, thereby enhancing the strain rate effect of the material and improving the ability to absorb and transform the kinetic energy of space debris.

[0046] For example, the sandwich structure is made of shape memory polymer material by 3D printing technology, and the sandwich structure is formed by a plurality of arms cross-connected to each other, and the structural deformation is achieved by thermal stimulation. Figure 1 As shown, the sandwich structure is a cross-arm structure, the two ends of the cross-arm are respectively connected to the upper and lower surfaces of two adjacent layers of the debris protection structure, the cross-arm is made of shape memory polymer material, and a heating plate is attached to the surface of the cross-arm.

[0047] Furthermore, the debris protection structure includes two usage states:

[0048] State 1: folded state, during the ascent of the spacecraft, the sandwich structure is in a compressed state;

[0049] State 2: Deployment state. After the spacecraft reaches the orbit, the heating plate on the surface of the sandwich structure is heated by the power supply inside the spacecraft, and the sandwich structure is deployed along the direction of the space debris impact based on the material properties of the shape memory polymer.

[0050] For example, Figure 2As shown, before ascending, the sandwich structure is in a compressed state, which can effectively reduce the ascending size and volume of the protective structure; after being installed in place on orbit, the heating plate is heated by the power supply in the spacecraft, and the sandwich structure is expanded along the impact direction of space debris based on the characteristics of shape memory polymer materials, thereby increasing the spacing between each protective layer, increasing the diffusion path of the debris cloud, increasing the effective area, and reducing the damage effect of space debris; the sandwich structure has a macro expansion rate of more than 200% along the impact direction of space debris;

[0051] When the debris protection structure intercepts large-sized space debris, such as space debris with a size of 3 cm, it is first broken up by the mesh protection layer to promote the large-sized space debris to break up and form a primary debris cloud; then it is broken up and converted into kinetic energy by the wave impedance protection layer to promote the primary debris cloud to further break up and partially change phases to form a secondary debris cloud; then it is acted upon by the energetic protection layer to greatly reduce the kinetic energy of the secondary debris cloud and promote the phase change of most of the debris to form a tertiary debris cloud; finally, it is acted upon by the energy-absorbing protection layer to absorb and convert the kinetic energy of the tertiary debris cloud to ensure that the debris passing through the energy-absorbing protection layer are all fragments below the millimeter level that pose no threat to the spacecraft.

[0052] The space debris protection structure provided by the present invention can be used to effectively protect spherical space debris with an impact speed of more than 5 km / s and a diameter of more than 1 cm.

[0053] When the mesh protective layer is made of alloy steel wire mesh, such as 1Cr18Ni9Ti, the density of each layer is 0.2-1.2g / cm 2 , thickness is 1-6mm; the wave impedance protection layer is made of titanium alloy-aluminum alloy-fiber, such as Ti6Al4V-Al2014-Kevlar KM2, and the density of each layer is 0.82~2.328g / cm 2 , thickness is 3-8mm; the energetic protective layer is made of PTFE / Al, and the density of each layer is 0.22-1.32g / cm 2 , thickness is 1-6mm; the energy absorption and protection layer is made of aramid fiber cloth, and the density of each layer is 0.16-0.96g / cm 2 , thickness is 1 to 6 mm; in the unfolded state, the interval between adjacent protective layers is 50 to 400 mm; in the folded state, the interval between adjacent protective layers is 10 to 100 mm.

[0054] When the above protection structure is adopted, the folded volume is 500~82500cm 3 ; The weight is 0.3 to 10 kg; numerical simulation and ground verification have shown that this protective structure has not failed, and can effectively enhance the spacecraft's ability to protect against hypersonic impacts from large-sized space debris.

[0055] On the other hand, the present invention also provides a space debris protection structure design method for designing and verifying the space debris protection structure, such as Figure 3 As shown, the following steps are included:

[0056] S1. Input the orbit information of the spacecraft and obtain the impact conditions of the space debris under the orbit according to the space debris simulation software;

[0057] The space debris simulation software can be ORDEM2000, MASTER or SDEEM2015; the impact conditions are, for example, spherical space debris with a speed of 7 km / s and a diameter of 3 cm;

[0058] S2. Determine the design plan of the protection structure, and determine the number, size, thickness and spacing of each type of protection layer based on the constraints including uplink mass, size, volume, protection area and space debris impact conditions;

[0059] Combined with the existing data, the parameters of the protective structure are estimated. For example, the thickness of the mesh protective layer is 4 mm, the material is 1Cr18Ni9Ti, and the surface density is 0.8 g / cm 2 The wave impedance protection layer is 4mm thick, made of Ti6Al4V-Al2014-KevlarKM2, with thicknesses of 2mm-1mm-1mm and surface density of 1.419g / cm 2 ; The thickness of the energetic protective layer is 3mm, the material is PTFE / Al, and the surface density is 0.66g / cm 2 ; The thickness of the energy-absorbing protective layer is 2mm, the material is aramid fiber cloth, and the surface density is 0.29g / cm 2 ; In the unfolded state, the distance between adjacent protective layers is 240mm; in the folded state, the distance between adjacent protective layers is 48mm.

[0060] S3, establish a numerical simulation model and obtain simulation results. If the simulation result shows that it cannot provide effective protection, return to S2, optimize and determine the protection structure design scheme. If the simulation result shows that it can provide effective protection, proceed to the next step S4;

[0061] Autodyn or LS-DYNA software is used for simulation; Shock or Tillotson is used as the material state equation, Johnson Cook or Steinberg Guinan is used as the material model, and Grady SpallModel is used as the failure model.

[0062] S4. Determine the ground test plan. If the ground test verification capability cannot meet the impact conditions, then establish equivalent impact conditions that meet the ground test verification capability based on the principle of equivalent damage effect; if the ground test verification capability meets the impact conditions, conduct the test according to the actual impact conditions;

[0063] If the impact speed exceeds 7 km / s or the size of the spherical fragments exceeds the millimeter level, the ground verification capability cannot meet the impact conditions, and equivalent impact conditions need to be established based on the equivalence principle;

[0064] S5. Conduct ground verification tests, prepare various types of protective layers and sandwich structures, establish a ground verification test system according to the design plan and impact conditions, and conduct ground verification tests; specific test steps are as follows:

[0065] (1) Fixing the protective structure into the impact cavity;

[0066] (2) Install the speed measuring device and high-speed photography device at appropriate locations;

[0067] (3) installing the simulated debris into the launch device;

[0068] (4) Adjust the parameters of the launch device, turn on the speed measuring device and high-speed photography device, and evacuate the impact chamber to a vacuum;

[0069] (5) Conducting impact tests;

[0070] S6. Determine the test results and the effect of the protective structure. If the protective structure can effectively protect against the impact of debris, the design solution is feasible. If the protective structure cannot effectively protect against the impact of debris, analyze the cause of the failure. If it is a problem with the design solution of the protective structure, return to step S2 to optimize and determine the design solution of the protective structure. If it is a problem with the ground test solution, return to step S4 to optimize and determine the ground test solution.

[0071] The failure of the protective structure means that all protective structures are penetrated; check the ground verification system parameter settings and the equipment itself. If there are any problems, return to step S4 to correct the ground test parameters; if there are no problems, return to step S2 to optimize the number, size, thickness of various protective layers of the protective structure and the spacing distance parameters of each protective layer.

[0072] The reliability verification of space debris protection structure is achieved through a design method that combines numerical simulation with ground verification tests.

[0073] The technical solution of the present invention is explained below in conjunction with specific embodiments.

[0074] Example 1

[0075] Design a space debris protection structure to protect spherical space debris with an impact velocity of 7 km / s and a diameter of 3 cm.

[0076] The protective structure of the present invention, that is, the mesh protective layer, the wave impedance protective layer, the energy-containing protective layer, and the energy-absorbing protective layer are arranged in sequence from outside to inside along the impact direction of space debris, and the intervals between the layers are adjusted using a sandwich structure.

[0077] The mesh protective layer is 4mm thick, made of 1Cr18Ni9Ti, and has a density of 0.8g / cm 2 The wave impedance protection layer is 4mm thick, made of Ti6Al4V-Al2014-KevlarKM2, with thicknesses of 2mm-1mm-1mm and surface density of 1.319g / cm 2 ; The thickness of the energetic protective layer is 3mm, the material is PTFE / Al, and the surface density is 0.66g / cm 2 ; The thickness of the energy-absorbing protective layer is 2mm, the material is aramid fiber cloth, and the surface density is 0.29g / cm 2 ; In the unfolded state, the distance between adjacent protective layers is 240mm; in the folded state, the distance between adjacent protective layers is 48mm.

[0078] The folded volume of the protective structure is 14940cm 3 ; The weight is 3kg; numerical simulation and ground verification have shown that this protective structure has not failed.

[0079] Example 2

[0080] The space debris protection structure is designed to protect spherical space debris with an impact velocity of 5 km / s and a diameter of 1 cm.

[0081] The protective structure of the present invention, that is, the mesh protective layer, the wave impedance protective layer, the energy-containing protective layer, and the energy-absorbing protective layer are arranged in sequence from outside to inside along the impact direction of space debris, and the intervals between the layers are adjusted using a sandwich structure.

[0082] The mesh protective layer is 2mm thick, made of 1Cr18Ni9Ti, and has a density of 0.4g / cm 2 The wave impedance protection layer is 4mm thick, made of Ti6Al4V-Al2014-KevlarKM2, with thicknesses of 2mm-1mm-1mm and surface density of 1.314g / cm 2 ; The thickness of the energetic protective layer is 4mm, the material is PTFE / Al, and the surface density is 0.88g / cm 2 ; The thickness of the energy-absorbing protective layer is 4mm, the material is aramid fiber cloth, and the surface density is 0.58g / cm 2 ; In the unfolded state, the distance between adjacent protective layers is 200mm; in the folded state, the distance between adjacent protective layers is 40mm.

[0083] The folded volume of the protective structure is 1340cm 3 ; The weight is 0.6kg; Numerical simulation and ground verification have shown that this protective structure has not failed.

[0084] Comparative Example 1

[0085] Design a space debris protection structure to protect spherical space debris with an impact velocity of 7 km / s and a diameter of 3 cm.

[0086] Adopt 6-layer aluminum plate protection structure.

[0087] Each layer of aluminum plate is 4mm thick, made of 6A06-T6, and the distance between two adjacent layers is 200mm. The volume of the protective structure is 90000cm 3 ; The weight is 6kg; Numerical simulation and ground verification have shown that this protective structure has not failed.

[0088] Comparative Example 2

[0089] A three-layer aluminum plate protection structure is designed to make the volume and weight of the protection structure close to those in Example 1. Numerical simulation and ground tests are used to verify whether this protection structure can protect spherical space debris with an impact speed of 7 km / s and a diameter of 3 cm.

[0090] 3-layer aluminum plate protection structure, each layer of aluminum plate is 3.8mm thick, the material is 6A06-T6, the distance between two adjacent layers is 73mm, the volume of the protection structure is 15030cm 3 ; The weight is 3kg; both numerical simulation and ground verification show that this protective structure has failed.

[0091] It can be seen from Example 1 and Comparative Example 1 that when the same protection requirements are met, the protection structure of the present invention has an uplink volume and weight that are much lower than those of the existing structure; it can be seen from Example 1 and Comparative Example 2 that when the uplink volume and weight of the protection structure are close, the protection structure of the present invention can meet the protection requirements, while the existing structure is penetrated; it can be seen from Examples 1 and 2 that the present invention can flexibly adapt to the protection of space debris of various sizes by adjusting the thickness of each protection layer.

[0092] In summary, compared with conventional protection structures, the present invention can not only effectively protect against large-sized space debris, but also significantly reduce the uplink size and volume of the protection structure while improving the protection capability.

[0093] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A space debris protection structure, characterized in that: Including mesh protective layer, wave impedance protective layer, energy-containing protective layer, energy-absorbing protective layer, and sandwich structure; The mesh protection layer, wave impedance protection layer, energy-containing protection layer, and energy-absorbing protection layer are arranged in sequence from outside to inside along the impact direction of the space debris; the protection layers are connected by a sandwich structure, the sandwich structure is made of shape memory polymer material through 3D printing technology, and the sandwich structure is formed by a plurality of arms cross-connected to each other, and structural deformation is achieved through thermal stimulation; A heating sheet is attached to the surface of the sandwich structure, and the sandwich structure is made of a shape memory polymer material, which can fold and unfold autonomously at a set temperature; After being installed in place on orbit, the heating plate is heated by the power supply in the spacecraft, and the sandwich structure is unfolded along the impact direction of the space debris based on the material properties of the shape memory polymer, thereby increasing the spacing between the protective layers, making the diffusion path of the debris cloud longer and the effective area larger; Applicable to spherical space debris with an impact speed of more than 5 km / s and a diameter of more than 1 cm.

2. The space debris protection structure according to claim 1, characterized in that: The debris protection structure includes two usage states: State 1: Folded state, during the ascent of the spacecraft, the debris protection structure is in the folded state; State 2: Deployment state: after the spacecraft reaches orbit, the sandwich structure unfolds along the impact direction of space debris.

3. The space debris protection structure according to claim 1, characterized in that: The mesh protective layer is one of aluminum alloy wire mesh, alloy steel wire mesh and titanium alloy wire mesh.

4. The space debris protection structure according to claim 1, characterized in that: The wave impedance protection layer is composed of three high-strength alloys or fiber materials arranged in a density gradient.

5. The space debris protection structure according to claim 4, characterized in that: The high-strength alloy is one or more of titanium alloy, aluminum alloy, and magnesium alloy, and the fiber material is one or more of polyimide fiber, silicon carbide fiber, basalt fiber, Kevlar fiber, carbon fiber, and PBO fiber.

6. The space debris protection structure according to claim 1, characterized in that: The energetic protective layer is composed of energetic materials, and the energetic material components are polytetrafluoroethylene / aluminum or aluminum / nickel.

7. The space debris protection structure according to claim 1, characterized in that: The energy absorbing protective layer is an aramid fiber cloth filled with a shear thickening liquid.

8. A method for designing a space debris protection structure, characterized in that: The design of the space debris protection structure according to any one of claims 1 to 7 comprises the following steps: S1. Input the orbit information of the spacecraft, and obtain the impact conditions of the space debris under the orbit according to the space debris simulation software, the impact speed is more than 5 km / s, and the diameter is more than 1 cm of spherical space debris; S2. Determine the design plan of the protection structure, and determine the number, size, thickness and spacing of each type of protection layer based on the constraints including uplink mass, size, volume, protection area and space debris impact conditions; It comprises a mesh protective layer, a wave impedance protective layer, an energetic protective layer, an energy absorbing protective layer, a sandwich structure and a heating sheet; the mesh protective layer, the wave impedance protective layer, the energetic protective layer and the energy absorbing protective layer are arranged in sequence from outside to inside along the impact direction of the space debris; S3, establish a numerical simulation model and obtain simulation results. If the simulation result shows that it cannot provide effective protection, return to S2, optimize and determine the protection structure design scheme. If the simulation result shows that it can provide effective protection, proceed to the next step S4; S4. Determine the ground test plan. If the ground test verification capability cannot meet the impact conditions, then establish equivalent impact conditions that meet the ground test verification capability based on the principle of equivalent damage effect; if the ground test verification capability meets the impact conditions, conduct the test according to the actual impact conditions; S5. Conduct ground verification tests, prepare various types of protective layers and sandwich structures, establish a ground verification test system according to the design plan and impact conditions, and conduct ground verification tests; the surface of the sandwich structure is affixed with a heating plate, and the sandwich structure is made of shape memory polymer material, which can fold and unfold autonomously at a set temperature; S6. Determine the test results and the effectiveness of the protective structure. If the protective structure can effectively protect against debris impact, the design is feasible; If the protective structure cannot effectively protect against debris impact, the cause of the failure is analyzed. If it is a problem with the protective structure design plan, return to step S2 to optimize and determine the protective structure design plan. If it is a problem with the ground test plan, return to step S4 to optimize and determine the ground test plan.

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