Shape memory space shading mechanism with large folding-unfolding ratio and shading method

Abstract

The invention provides a shape memory space shading mechanism with a large folding-unfolding ratio and a shading method. The shading mechanism comprises a plurality of groups of shape memory pod rod unfolding mechanisms, shape memory locking and releasing mechanisms with the same number, shading films with the same number and fixing devices. The fixing device is installed at one end of an object to be shaded and fixes and supports the locking and releasing mechanism and the pod rod unfolding mechanism. The locking and releasing mechanism locks or releases the pod rod unfolding mechanism in the folded state after locking, so that the pod rod unfolding mechanism can be reliably fixed with the fixing device at the ascending section and the fixed constraint of the pod rod unfolding mechanism is relieved at the preset stage; the shape memory pod rod unfolding mechanism and the shading film are arranged in a penetrating manner and are connected with each other in a threading manner; a heating device is adhered to the surface of the shape memory pod rod unfolding mechanism, the shape memory pod rod unfolding mechanism can be heated to deform after being unfixed, and the shape memory pod rod unfolding mechanism drives the rolled shading film to unfold and cover the to-be-shaded object in the process of extending in the length direction of the to-be-shaded object.

Description

Technical Field

[0001] This invention belongs to the field of aircraft shading structure technology, and specifically relates to a large aspect ratio shape memory space shading mechanism and shading method, which can be used for shading and heat insulation of aircraft such as the final stage of launch vehicles. Background Technology

[0002] In the aerospace field, the design and performance of the rocket's final stage directly affect the spacecraft's orbital parameters and operational effectiveness. Cryogenic propellants offer advantages such as high specific impulse and non-toxicity, making them particularly advantageous for use in rocket final stages. However, under space radiation conditions, cryogenic propellants are prone to evaporation and difficult to store long-term. To achieve extended on-orbit operation, efficient heat insulation using light-shielding devices can be employed to block external light sources, such as sunlight and reflected light from the Earth, reducing propellant evaporation. This effectively improves the long-term on-orbit capability of rocket final stages, providing protection for spacecraft platforms in orbit and enhancing the deployment flexibility of space equipment.

[0003] The shading device needs to deploy to a sufficient area to protect platforms such as the rocket's final stage. Constrained by external aerodynamic loads during the rocket's ascent phase and the space of the rocket fairing, it requires a large unfolding ratio to achieve small-volume storage during launch and large-area deployment during operation, while also maintaining high reliability to complete the intended space mission. Traditional shading mechanisms primarily use mechanical springs or electric methods to retract and deploy the shading film. These traditional solutions suffer from complex structures, large size, and heavy weight. Mechanical springs are prone to high impact and are susceptible to changes in ambient temperature, leading to insufficient or excessive spring stiffness and performance instability. Electric methods are limited by power supply and the stability of the mechanical transmission system, and also face challenges such as large mass, low reliability, and high maintenance costs.

[0004] To address these issues, this invention proposes a space shading mechanism based on shape memory polymer composite material that combines locking and releasing functions with folding and unfolding functions. The aim is to improve the reliability and stability of the shading mechanism, reduce costs and energy consumption, and meet the shading requirements of the rocket's final stage.

[0005] This invention uses shape memory polymer composite material as the key component material, and utilizes its unique shape memory properties to realize the folding and unfolding of the light-shielding mechanism. It effectively solves the problems of complex structure, large mass, large volume, large impact and high energy consumption in traditional solutions. It has the characteristics of simple structure, high storage ratio, lightweight, high reliability and strong environmental adaptability. Summary of the Invention

[0006] To overcome the shortcomings of existing technologies, the inventors have conducted intensive research and provided a shape memory spatial light-blocking mechanism and method with a large fold-to-expansion ratio. The mechanism uses carbon fiber reinforced shape memory polymer matrix composite material as the key component material and utilizes its unique shape memory characteristics to realize the folding and unfolding of the light-blocking mechanism. This effectively solves the problems of complex structure, large size and mass, and low reliability in traditional solutions. It has the characteristics of simple structure, small mass, high reliability, and strong environmental adaptability.

[0007] The technical solution provided by this invention is as follows:

[0008] In a first aspect, a shape memory spatial light-blocking mechanism with a large fold-to-expansion ratio is provided, comprising a shape memory pod-like rod unfolding mechanism, a shape memory locking and releasing mechanism, a light-blocking film, and a fixing device; the fixing device is installed at one end of the object to be light-blocked, fixing and supporting the shape memory pod-like rod unfolding mechanism and the shape memory locking and releasing mechanism; the shape memory locking and releasing mechanism locks or releases the shape memory pod-like rod unfolding mechanism in a folded state, so that the shape memory pod-like rod unfolding mechanism remains in a folded state or changes from a folded state to a released state; multiple sets of shape memory pod-like rod unfolding mechanisms and multiple light-blocking films are arranged alternately, and the light-blocking films are connected to the shape memory pod-like rod unfolding mechanisms by threading; as the shape memory pod-like rod unfolding mechanism extends along the length direction of the object to be light-blocked, it drives the rolled-up light-blocking film to unfold and cover the object to be light-blocked.

[0009] Secondly, a large aspect ratio shape memory space shading method, implemented using the large aspect ratio shape memory space shading mechanism described in the first aspect, includes:

[0010] During the rocket launch preparation and launch phases, the first step involves the shape memory pod extension mechanism being softened by heating, allowing it to retract around the drum under external force to reach a retracted state. The second step involves the locking strap holding the retracted shape memory pod extension mechanism tightly, with the round hole at the end of the locking strap fitting onto the conical surface of the locking base. The third step involves the shape memory locking plate of the shape memory locking release mechanism being softened by heating, and then the locking ball at the end of the shape memory locking plate is inserted into the groove under external force and held in a locked state before cooling and solidifying, thus completing the fixation of the retracted, high-ratio shape memory space light-shielding mechanism.

[0011] During the on-orbit phase, when protection of the rocket's final stage is required, the high-ratio shape memory space shading mechanism heats the shape memory locking layer to its glass transition temperature. The shape memory locking layer automatically returns to its initial released state, completing the unlocking and release of the shape memory pod extension mechanism. Subsequently, the shape memory pod extension mechanism is heated to its glass transition temperature, utilizing the shape memory effect to return it from its initial retracted state to its extended state, causing the shading film to unfold, ultimately achieving the covering of the object to be shaded.

[0012] The light-blocking mechanism and method with a large refractive ratio shape memory space provided by the present invention have the following beneficial effects:

[0013] (1) This invention provides a shape memory space light-shielding mechanism and light-shielding method with a large folding-to-expansion ratio. The light-shielding mechanism retracts during the rocket launch ascent phase and expands after entering space to shield the rocket body structure. The light-shielding mechanism uses shape memory polymer-based composite material pod rods combined with aluminum-coated film material. The unique shape memory characteristics of the shape memory polymer-based composite material pod rods are used to realize the retraction and expansion of the light-shielding mechanism, which effectively solves the problems of complex structure, large volume and mass, and low reliability in traditional solutions. At the same time, by adding carbon fiber reinforced shape memory polymer-based composite material connecting pieces between the two pod rods, the overall coverage of the combined configuration box of the frustum section and the straight cylinder section is achieved.

[0014] (2) The present invention provides a large folding ratio shape memory space light-blocking mechanism and light-blocking method, which implements a pleated design on the light-blocking film and fixes a roll at the far end of the shape memory pod rod unfolding mechanism so that the light-blocking film does not interfere during the rolling and unfolding process.

[0015] (3) The present invention provides a large folding ratio shape memory space light-blocking mechanism and light-blocking method. The light-blocking mechanism adopts a split light-blocking design with multiple sets of shape memory pod rod unfolding mechanisms and pleated light-blocking film. Compared with the integrated light-blocking design, it reduces the difficulty of rolling and unfolding the light-blocking film. Each set of shape memory pod rod unfolding mechanisms has greater independence and does not need to be limited by the unfolding or retraction rate of adjacent shape memory pod rod unfolding mechanisms, thus improving the reliability of light blocking. Attached Figure Description

[0016] Figure 1 A schematic diagram of the collapsed state of a shape memory spatial shading mechanism with a large fold-to-expansion ratio;

[0017] Figure 2 A schematic diagram of the semi-expanded state of a shape memory spatial shading mechanism with a large fold-to-expansion ratio;

[0018] Figure 3 A schematic diagram of the fully unfolded state of a shape memory spatial shading mechanism with a large aspect ratio;

[0019] Figure 4 Schematic diagram of the shape memory locking release mechanism in the released state;

[0020] Figure 5 A schematic diagram of the locking mechanism for the shape memory pod rod unfolding mechanism of the shape memory locking and releasing mechanism;

[0021] Figure 6 A schematic diagram of the unfolded state of the shape memory pod rod unfolding mechanism;

[0022] Figure 7 This is a schematic diagram of the fixing device;

[0023] Figure 8 A light-blocking film designed for wrinkles. Detailed Implementation

[0024] The features and advantages of the present invention will become clearer and more apparent from the following detailed description.

[0025] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments.

[0026] like Figure 1 , Figure 2 , Figure 3 As shown, this invention provides a shape memory spatial light-blocking mechanism with a large folding-to-expansion ratio, including a shape memory pod-like rod unfolding mechanism 2, a shape memory locking and releasing mechanism 3, a light-blocking film 4, and a fixing device 5. The fixing device 5 is installed at one end of the object to be blocked 1, fixing and supporting the shape memory pod-like rod unfolding mechanism 2 and the shape memory locking and releasing mechanism 3. The shape memory locking and releasing mechanism 3 locks or releases the shape memory pod-like rod unfolding mechanism 2 in the folded state, so that the shape memory pod-like rod unfolding mechanism 2 remains in the folded state or changes from the folded state to the released state. Six sets of shape memory pod-like rod unfolding mechanisms 2 and six light-blocking films 4 are arranged alternately. The light-blocking film 4 is connected to the shape memory pod-like rod unfolding mechanism 2 by threading, which is convenient to disassemble. As the shape memory pod-like rod unfolding mechanism 2 extends along the length direction of the object to be blocked 1, it drives the rolled-up light-blocking film 4 to unfold and cover the object to be blocked 1.

[0027] like Figure 4 , Figure 5As shown, the main function of the shape memory locking and releasing mechanism 3 is to lock and release the shape memory pod rod unfolding mechanism 2. It includes a shape memory locking plate layer 31, a locking band 32, and a locking base 34. The shape memory locking plate layer 31 has a straight shape in the locked state and an arc shape in the released state, with a locking ball 33 at its end. One side of the locking base 34 has the shape memory locking plate layer 31 and a truncated cone with a groove 35, while the other side is fixed to the fixing bracket 51 of the fixing device 5 via a threaded connector. One end of the locking band 32 is fixed to the bracket 52 of the fixing device 5 via a threaded connector. The other end is provided with a round hole that can be fitted onto the cone; the locking band 32 holds the shape memory pod rod unfolding mechanism 2 in the retracted state, and the round hole at the end of the locking band 32 fits onto the outer cone with groove 35 of the locking base 34. When the shape memory locking plate layer 31 in the locked state is fixed to the locking base 34 by the threaded connector, the locking ball 33 at the end of the shape memory locking plate layer 31 is inserted into the groove 35 to form a constraint on the locking band 32; by heating the shape memory locking plate layer 31 to the glass transition temperature, the lock state is converted to the release state, thereby releasing the constraint on the end of the locking band 32.

[0028] like Figure 5 , Figure 6 As shown, the shape memory pod unfolding mechanism 2 includes an upper shape memory pod 21, an intermediate connecting joint 22, a lower shape memory pod 23, and a roll 24; the lower shape memory pod 23 and the roll 24 are connected by threads, and the upper shape memory pod 21, the intermediate connecting joint 22, and the lower shape memory pod 23 are connected by high-temperature resistant adhesive; the shape memory pod 21 and the lower shape memory pod 23 have an initial folded state (rolled shape) and a deformed unfolded state (straight rod shape), and the intermediate connecting joint 22 has an initial folded state (rolled shape) and a deformed state (straight rod shape). The shape memory pod unfolding mechanism 2 retracts by heating the upper shape memory pod 21, the middle connecting joint 22, and the lower shape memory pod 23 until they soften, and then using external force to roll the upper shape memory pod 21, the middle connecting joint 22, and the lower shape memory pod 23 around the roll 24 until they are completely retracted. The unfolding of the shape memory pod unfolding mechanism 2 is achieved by electrically heating the upper shape memory pod 21, the middle connecting joint 22, and the lower shape memory pod 23 to the glass transition temperature to realize the transition from the retracted state to the unfolded state.

[0029] like Figure 7 As shown, the fixing device 5 includes a fixing bracket 51 and a bracket 52. The bracket 52 is used to fix the locking band 32. The number of brackets is the same as the number of corresponding shape memory locking and releasing mechanisms 3. The bracket 52 and the fixing bracket 51 are fixedly connected by threaded fasteners.

[0030] like Figure 8As shown, the light-shielding film 4 adopts a multi-layer structure with alternating layers of highly reflective aluminized thin film material and polymer mesh layer. The polymer mesh layer between adjacent aluminized thin film layers can effectively block radiation and protect the aircraft from heat. The light-shielding film 4 adopts a pleated design to ensure that no interference occurs inside the light-shielding film 4 during the retraction and expansion process.

[0031] When using the above-mentioned large-ratio shape memory spatial shading mechanism to implement shading, it is achieved in the following way:

[0032] During the rocket launch preparation and launch phases, the first step involves the shape memory pod extension mechanism 2 being softened by heating and then retracted around the drum under external force to reach a retracted state. The second step involves the locking band 32 holding the retracted shape memory pod extension mechanism 2 tightly, with the round hole at the end of the locking band 32 fitting around the truncated cone on the locking base 34. The third step involves the shape memory locking plate 31 of the shape memory locking release mechanism 3 being softened by heating. Subsequently, under external force, the locking ball 33 at the end of the shape memory locking plate 31 is inserted into the groove 35 and held in a locked state, then cooled and solidified, thus completing the fixation of the retracted large-ratio shape memory space light-shielding mechanism.

[0033] During the on-orbit phase, when protection of the rocket's final stage is required, the high-ratio shape memory space shading mechanism heats the shape memory locking layer 31 to its glass transition temperature. The shape memory locking layer 31 automatically returns to its initial released state, completing the unlocking and release of the shape memory pod extension mechanism 2. Subsequently, the shape memory pod extension mechanism 2 is heated to its glass transition temperature, and using the shape memory effect, it returns from its initial retracted state to its extended state, driving the shading film 4 to unfold, ultimately achieving the shading of the object to be shaded 1.

[0034] The present invention has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present invention. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and embodiments of the present invention without departing from the spirit and scope of the invention, and all such modifications and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims.

[0035] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A shape memory spatial light-blocking mechanism with a large aspect ratio, characterized in that, It includes a shape memory pod stem unfolding mechanism (2), a shape memory locking and releasing mechanism (3), a light-blocking film (4), and a fixing device (5); The fixing device (5) is installed at one end of the object to be shaded (1), fixing and supporting the shape memory pod stick unfolding mechanism (2) and the shape memory locking and releasing mechanism (3); the shape memory locking and releasing mechanism (3) locks or releases the shape memory pod stick unfolding mechanism (2) in the folded state, so that the shape memory pod stick unfolding mechanism (2) remains in the folded state or changes from the folded state to the released state; multiple sets of shape memory pod stick unfolding mechanisms (2) and multiple light-blocking films (4) are arranged alternately, and the light-blocking films (4) are connected to the shape memory pod stick unfolding mechanism (2) by threading; as the shape memory pod stick unfolding mechanism (2) extends along the length direction of the object to be shaded (1), it drives the rolled-up light-blocking film (4) to unfold and cover the object to be shaded (1).

2. The large aspect ratio shape memory spatial light-blocking mechanism according to claim 1, characterized in that, The shape memory pod unfolding mechanism (2) includes an upper shape memory pod (21), a middle connecting joint (22), a lower shape memory pod (23), and a roller (24). The lower shape memory pod (23) and the roller (24) are connected, and the upper shape memory pod (21), the middle connecting joint (22), and the lower shape memory pod (23) are connected by high-temperature resistant adhesive.

3. The large aspect ratio shape memory spatial light-blocking mechanism according to claim 2, characterized in that, The shape memory pod rod (21) and the lower shape memory pod rod (23) have an initial coiled state and a straight rod state after deformation and unfolding. The intermediate connecting joint (22) has an initial coiled state and an arc state after deformation and unfolding. The coiling process of the shape memory pod rod unfolding mechanism (2) is to heat the upper shape memory pod rod (21), the intermediate connecting joint (22), and the lower shape memory pod rod (23) until softened, and to use external force to make the upper shape memory pod rod (21), the intermediate connecting joint (22), and the lower shape memory pod rod (23) roll around the coil (24) until completely coiled. The unfolding of the shape memory pod rod unfolding mechanism (2) is to convert the coiled state to the unfolded state by electrically heating the upper shape memory pod rod (21), the intermediate connecting joint (22), and the lower shape memory pod rod (23) to the glass transition temperature.

4. The large aspect ratio shape memory spatial light-blocking mechanism according to claim 1, characterized in that, The shape memory locking and releasing mechanism (3) includes a shape memory locking plate (31), a locking band (32), and a locking base (34); the shape memory locking plate (31) has a straight shape in the locking state and an arc shape in the releasing state, and a locking ball (33) is provided at the end; the locking base (34) has a shape memory locking plate (31) and a cone with a groove (35) on one side, and is fixed to the fixing bracket (51) of the fixing device (5) on the other side; one end of the locking band (32) is fixed to the fixing device (5). The other end is machined with a round hole; the locking band (32) holds the shape memory pod rod unfolding mechanism (2) in the folded state, and the round hole at the end of the locking band (32) is fitted onto the cone of the locking base (34). The locking ball (33) at the end of the shape memory locking sheet (31) in the locked state is inserted into the groove (35) to form a constraint on the locking band (32); by heating the shape memory locking sheet (31) to the glass transition temperature, the lock state is converted to the release state, and the constraint on the end of the locking band (32) is released.

5. The large aspect ratio shape memory spatial light-blocking mechanism according to claim 1, characterized in that, The light-shielding film (4) adopts a multi-layer structure with alternating layers of aluminum-coated thin film material and polymer mesh layer.

6. The large aspect ratio shape memory spatial light-blocking mechanism according to claim 1, characterized in that, The light-shielding film (4) adopts a pleated design so that no interference occurs inside the light-shielding film (4) during the folding and unfolding process.

7. The large aspect ratio shape memory spatial light-blocking mechanism according to claim 1, characterized in that, The fixing device (5) includes a fixing bracket (51) and a bracket (52). The fixing bracket (51) is equipped with a locking base (34) of the shape memory locking release mechanism (3) and a bracket (52). The bracket (52) is used to fix the locking band (32).

8. The large aspect ratio shape memory spatial light-blocking mechanism according to claim 7, characterized in that, The number of brackets (52) is the same as the number of shape memory locking and releasing mechanisms (3).

9. A light-shielding method for a large aspect ratio shape memory spatial light-shielding mechanism as described in claims 1 to 8, characterized in that, include: In the rocket launch preparation and launch phases, the first step is to soften the shape memory pod rod unfolding mechanism (2) by heating, and then retract it around the drum (24) under external force to reach the retracted state; the second step is to tighten the retracted shape memory pod rod unfolding mechanism (2) with the locking band (32), and the round hole at the end of the locking band (32) is fitted onto the outside of the cone on the locking base (34); the third step is to soften the shape memory locking sheet (31) of the shape memory locking release mechanism (3) by heating, and then the locking ball (33) at the end of the shape memory locking sheet (31) is inserted into the groove (35) under external force and kept in the locked state and cooled and solidified, thus completing the fixation of the retracted large folding ratio shape memory space light shielding mechanism; During the on-orbit phase, when it is necessary to protect the final stage of the rocket, the large-ratio shape memory space shading mechanism heats the shape memory locking layer (31) to the glass transition temperature, and the shape memory locking layer (31) automatically returns to the initial release state, completing the unlocking and release of the shape memory pod rod unfolding mechanism (2); then the shape memory pod rod unfolding mechanism (2) is heated to the glass transition temperature, and the shape memory effect is used to restore it from the initial folded state to the unfolded state, driving the shading film to unfold, and finally achieving the shading of the object to be shaded (1).

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