Winding type extension mechanism and flexible solar wing based on self-repairing shape memory polymer composite material

Abstract

The application discloses a winding type stretching mechanism based on a self-repairing shape memory polymer composite material and a flexible solar wing, and relates to the technical field of spacecraft power systems. The stretching mechanism comprises closable stretching pipes, flexible heating films, mounting brackets and winding drums which are arranged at intervals. The closable stretching pipes are made of a self-repairing shape memory polymer composite material, and are provided with open slits in the axial direction. In the deployment stage, the flexible heating films are powered on to generate thermal excitation to drive the stretching pipes to return to the initial shape and make the opposite sides overlap, so that the dynamic keys inside the material trigger interfacial diffusion and self-healing, and the slits at the overlapping positions are closed. The flexible heating films are used as the physical isolation layer and are arranged between the adjacent pipe walls, so that the unintended self-adhesion of the stretching pipes in the heated and wound state is effectively prevented, seamless closure of the stretching pipes is realized through the self-healing technology, and the requirements of high storage ratio and high deployment stiffness of the flexible solar wing are met.

Description

Technical Field

[0001] This invention relates to the field of spacecraft power system technology, and in particular to a winding extension mechanism and a flexible solar array based on a self-healing shape memory polymer composite material. Background Technology

[0002] With the increasing energy demands of modern satellites and space probes, ultra-large flexible solar arrays have become a core development direction for spacecraft power systems due to their advantages such as high packing ratio and light weight. To achieve compact packing and reliable on-orbit deployment of large-area solar arrays, existing technologies mostly employ roll-up extension mechanisms.

[0003] However, traditional winding extension mechanisms (such as ordinary composite open thin-walled tubes) require a through slit designed along the axial direction to achieve flattening and winding. This open structure results in insufficient torsional and bending stiffness of the extension tube after it is fully deployed in orbit, severely affecting the overall fundamental frequency and dynamic stability of ultra-large flexible solar arrays in complex space environments. While traditional closed tubes have high stiffness, current technologies cannot achieve flattening and winding with a high retraction ratio; that is, current technologies cannot simultaneously meet the requirements of high retraction ratio and high deployment stiffness for flexible solar arrays. Summary of the Invention

[0004] The purpose of this invention is to provide a winding extension mechanism and a flexible solar wing based on a self-healing shape memory polymer composite material, which can meet the requirements of high retraction ratio and high deployment stiffness of the flexible solar wing.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a winding extension mechanism based on a self-healing shape memory polymer composite material, comprising: Two spaced-apart closable extension tubes are made of self-healing shape memory polymer composite material. In the initial form, the wall of the circular tube segment of the closable extension tube has an axially open gap. The opposite sides of the open gap overlap to form an overlap area, and there is a straight extension section on the side of the circular tube segment. The extension sections of the two closable extension tubes are spaced-apart and opposite to each other. A flexible heating film is attached to the surface of a closable and extendable tube. In the flattened and rolled-up storage state, the heating film acts as a physical isolation layer between adjacent tube wall layers to prevent unintended self-adhesion between adjacent tube wall layers when heated. The mounting bracket is located at one end of two spaced-apart closable extension tubes; The reel is installed at the other end of two spaced-apart closable extension tubes. Before launch, its outer periphery is wound with a closable extension tube in a flattened and stored state and attached with a flexible heating film, which serves as a conformal storage base for the closable extension tube. During the on-orbit deployment phase, the heating film generates thermal excitation when energized, driving the closable extension tube to return from its flattened, wound, and stored state to its initial shape and tightly fitting the opposite sides of the overlapping area. This triggers the dynamic reversible bonds inside the polymer composite material to diffuse across the interface and self-heal, thus sealing the opening gaps.

[0006] Optionally, during the process of the closable extension tube returning from the flattened and wound state to the initial form, the two side walls of the closable extension tube naturally overlap and align after docking to form an overlap area, and the overlap area is located at the junction of the circular tube segment and the extension segment. In the initial form, the closable extension tube has an asymmetrical cross-sectional configuration, and the circular tube segment and the extension segment are continuously and integrally connected.

[0007] Optionally, a flexible heating film is attached to the surface of a closable extendable tube. When the closable extendable tube is in a flattened state, it is in the form of a stacked flat plate. The flexible heating film includes a first attachment film and a second attachment film. The first attachment film and the second attachment film are located on the upper and lower surfaces of the stacked flat plate, respectively, and are staggered along the width direction of the plate. On the orthographic projection plane perpendicular to the thickness direction of the plate, the projection areas of the first attachment film and the second attachment film are connected or overlapped to achieve uninterrupted continuous coverage in the width direction of the stacked flat plate.

[0008] Optionally, the closable extension tube, in its flattened temporary state, comprises an upper plate and a lower plate. One end of the lower plate is continuously and integrally connected to the lower side of the upper plate, and the remaining part of the lower plate is arranged parallel to and spaced apart from the upper plate. During the process of restoring from the flattened temporary state to the initial shape, the upper plate curls inward under thermal excitation to form a circular tube segment and an overlapping area, while the lower plate remains in a straight and extended state to form an extension section.

[0009] Optionally, the flexible heating film includes a third, a fourth, and a fifth attached film; the third attached film is located between the lower surface of the upper plate and the upper surface of the lower plate, and is attached to the lower surface of the upper plate; the fourth attached film is located on the upper surface of the upper plate; the third and fourth attached films are staggered in the width direction of the upper plate, and on the orthographic projection plane perpendicular to the thickness direction of the upper plate, the projection areas of the third and fourth attached films are connected or overlapped to achieve uninterrupted continuous coverage in the width direction of the upper plate; the fifth attached film is attached to the lower surface of the lower plate.

[0010] Optionally, the outer radius of the closable extension tube ranges from 30 mm to 80 mm, the wall thickness ranges from 1.5 mm to 4.0 mm, and the width of the extension section ranges from 20 mm to 40 mm.

[0011] Optionally, the overlap size of the opposite sides of the opening slit is 1 / 10 to 1 / 12 of the circumference of the circular pipe segment.

[0012] In a second aspect, the present invention also provides a flexible solar array, comprising a roll-up extension mechanism according to any implementation of the first aspect; and Flexible battery film laid on the extension sections of two closable extension tubes.

[0013] Alternatively, the flexible heating film can be powered by the power source of the spacecraft with the flexible solar panels installed.

[0014] Thirdly, the present invention also provides an on-orbit deployment method based on the flexible solar array of the second aspect, comprising the following steps: S1. Thermally driven unfolding step: The power supply drives the flexible heating film to heat up to above the glass transition temperature of the self-healing shape memory polymer composite material, so that the flattened, wound, and stored closable stretchable tube softens and releases internal stress, returning to its initial shape, while driving the flexible battery film laid on its extension section to unfold smoothly. S2, Gap Closure and In-situ Self-Healing Steps: Maintain or continue to raise the temperature of the flexible heating film to above the self-healing activation threshold of the self-healing shape memory polymer composite material and maintain it for a preset time, driving the dynamic reversible covalent bonds or supramolecular forces in the self-healing shape memory polymer composite material matrix to undergo cross-interface diffusion and physical entanglement, so that the opening gap of the extension tube is tightly attached and spontaneously fused and closed. S3. Cooling and curing step: Stop the power supply and allow it to cool naturally, so that the closable extension tube locks in the current configuration.

[0015] The above-described technical solution of the present invention has the following advantages: The present invention provides a winding extension mechanism based on self-healing shape memory polymer composite material. This mechanism utilizes a flexible heating film that has the dual functions of thermal excitation and physical isolation, effectively preventing the shape memory polymer from unexpectedly self-adheding under heat and in the stored state. The axial opening gaps are sealed by in-situ self-healing technology, achieving a balance between storage performance and load-bearing performance.

[0016] The flexible solar array provided by this invention adopts the above-mentioned winding extension mechanism based on self-healing shape memory polymer composite material, which improves the reliability of on-orbit deployment and can meet the requirements of high retraction ratio and high deployment stiffness of flexible solar array. Attached Figure Description

[0017] The accompanying drawings are provided for illustrative purposes only, and the proportions and quantities of the components in the drawings may not be consistent with the actual product.

[0018] Figure 1 This is a schematic diagram of a winding extension mechanism based on a self-healing shape memory polymer composite material in Embodiment 1 of the present invention; Figure 2This is a schematic diagram of the structure of a closable extension tube in its initial form (opening gap not yet healed) according to Embodiment 1 of the present invention; Figure 3 yes Figure 1 A frontal view of the end of the retractable extension tube; Figure 4 yes Figure 3 Enlarged diagram of part A in the diagram; Figure 5 This is a schematic diagram of the structure of a closable extension tube in its initial form (opening gap healed) according to Embodiment 1 of the present invention; Figure 6 This is a front view of the end of the closable extension tube in the flattened temporary state after a flexible heating film has been attached, according to Embodiment 1 of the present invention. Figure 7 yes Figure 6 A schematic diagram of the end structure after the intermediate pressure flattening state transforms into the initial state; Figure 8 This is a schematic diagram of the structure of the closable extendable tube in the flattened and wound storage state in Embodiment 1 of the present invention (flexible heating film is not shown). Figure 9 This is a schematic diagram of the structure of a closable extension tube in its initial form (opening gap not yet healed) according to Embodiment 2 of the present invention; Figure 10 yes Figure 9 A frontal view of the end of the retractable extension tube; Figure 11 yes Figure 10 Enlarged schematic diagram of part B in the diagram; Figure 12 This is a front view of the end of the closable extendable tube in the flattened temporary state after a flexible heating film has been attached, according to Embodiment 2 of the present invention. Figure 13 yes Figure 12 A schematic diagram of the end structure after the intermediate pressure flattening state transforms into the initial state; Figure 14 This is a schematic diagram of a flexible solar panel in a wound state according to Embodiment 3 of the present invention; Figure 15 This is a schematic diagram of the flexible solar array in the deployed state in Embodiment 3 of the present invention.

[0019] In the picture: 1: Winding extension mechanism; 11: Closable extension tube; 111: Overlap area; 112: Extension section; 12: Flexible heating film; 121: First attached film; 122: Second attached film; 123: Third attached film; 124: Fourth attached film; 125: Fifth attached film; 13: Install the bracket; 14: Roll; 2: Flexible battery film. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] It should be noted that, unless otherwise explicitly specified and limited, the terms "connection," "installation," and "fixation," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0022] Example 1 The present invention provides a winding extension mechanism 1 based on a self-healing shape memory polymer composite material, which is mainly used in deployable components (such as flexible solar panels) in the space environment.

[0023] like Figure 1 As shown, the winding extension mechanism 1 in this embodiment includes two spaced-apart closable extension tubes 11, a flexible heating film 12 for controlling the shape of the extension tubes, a mounting bracket 13, and a roll 14.

[0024] The closable extendable tube 11 is made of a self-healing shape memory polymer composite (SH-SMPC). This material possesses shape memory effect and interfacial self-healing properties, and can undergo phase transitions (such as glass transitions) upon thermal stimulation, thereby achieving reversible morphological switching. Simultaneously, it contains dynamic reversible covalent bonds or supramolecular forces, enabling cross-interfacial diffusion and recombination upon contact and reaching a specific temperature. It should be noted that the self-healing shape memory polymer composite used in this invention is an existing material and will not be described further here.

[0025] See Figures 2 to 4The closable extendable tube 11 has an asymmetrical cross-sectional configuration in its initial form (i.e., the deployed working state). Specifically, the main body of the closable extendable tube 11 is cylindrical (circular tube segment), and a straight extension segment 112 is provided at one end in its extension direction. The circular tube segment and the extension segment 112 are continuously and integrally connected. The main body of the closable extendable tube 11 has an axially open slot, and the opposite sides of the open slot overlap to form an overlapping area 111 with overlapping opposite sides.

[0026] See Figure 5 and Figure 6 The flexible heating film 12 is attached to the outer surface of the closable extension tube. When the winding extension mechanism 1 is in the flattened winding and storage state, the two closable extension tubes 11 are coiled in a stacked flat plate shape on the roll 14 (see...). Figure 7 and Figure 14 At this time, the flexible heating film 12 attached to the surface of the closable extension tube 11 not only serves as a heating element, but also as a physical isolation layer between adjacent tube wall layers to prevent the tube walls from unexpectedly self-adheding under heat or long-term contact, ensuring smooth separation when expansion is required.

[0027] In a specific example, the flexible heating film 12 includes a first attachment film 121 and a second attachment film 122. The first attachment film 121 and the second attachment film 122 are located on the upper and lower surfaces of the stacked flat plate, respectively, and are staggered along the width direction of the plate. On the orthographic projection plane perpendicular to the thickness direction of the plate, the projection areas of the first attachment film 121 and the second attachment film 122 are connected or overlapped to achieve uninterrupted continuous coverage in the width direction of the stacked flat plate.

[0028] See Figure 1 Mounting bracket 13 is located at one end of the two closable extendable tubes, serving as a fixed end for installation on the spacecraft. Drum 14 is mounted at the other end, serving as a conformal storage base for the closable extendable tube 11. Before launch, the closable extendable tubes are deformed from their initial shape to a flattened temporary state with a flexible heating film 12 attached (see [link to product details]). Figure 5 ), and fix it to the spool 14, i.e., in the flattened, wound, and stored state (see Figure 7 and Figure 14 ).

[0029] During the in-orbit deployment phase, when deployment is required, the flexible heating film 12 is energized to generate heat. This heat is transferred to the self-healing shape memory polymer composite material, raising its temperature above its glass transition temperature (Tg). The material transitions from a glassy state to a highly elastic state, releasing internal stress and allowing the closable extension tube 11 to extend as described above. Figure 1 As shown in the diagram. See also the following for details. Figure 5 pipe wall layer along Figure 5The arc-shaped arrow in the diagram indicates a return to a closed circular tube structure. The originally separated side overlap area 111 triggers dynamic bond recombination (self-healing) in the polymer composite material under thermal excitation, fusing and sealing the axial opening gap (see...). Figure 8 ), complete the deployment.

[0030] To balance the unfolding force and structural compactness, in this embodiment, the outer radius of the closable extension tube 11 is preferably between 30mm and 80mm, the wall thickness is preferably between 1.5mm and 4.0mm, and the width of the extension section 112 is preferably between 20mm and 40mm. The overlap size of the overlap area 111 (i.e., the side overlap width) is preferably 1 / 10 to 1 / 12 of the circumference of the circular tube segment of the closable extension tube 11 to ensure sufficient self-healing area and structural strength. In a specific example, when the cross-sectional geometric parameters of the closable extension tube 11 are set as follows: outer radius 50mm, wall thickness 2mm, extension section length (dimension extending outward from the circular tube segment) 30mm, and the overlap size of the overlap area 111 is 30mm, calculations have verified that the torsional constant (I) of the closed extension tube formed after self-healing is... t It can reach 173,717 mm. 4 The torsional constant (I) of the open extension tube before self-healing. t0 Only 482.1 mm 4 That is, after self-healing and reconstructing into a closed pipeline, the torsional stiffness of the extension pipe is increased to about 360 times that of the open form.

[0031] Example 2 See Figures 9 to 13 The difference between this second embodiment and the first embodiment is that it provides another type of closable extendable tube 11. The structure of this closable extendable tube 11 is different before it self-heals. When the closable extendable tube 11 is in a flattened temporary state (i.e., a flat plate state before deployment), as... Figure 12 As shown, it comprises an upper plate and a lower plate. One end of the lower plate is integrally connected to the lower side of the upper plate, while the remaining portion is arranged parallel to and spaced apart from the upper plate. See [link to documentation] for the process of restoring from the flattened temporary state to the initial shape. Figure 12 and Figure 13 The upper plate is rolled inward under thermal excitation to form a circular tube segment and an overlapping area, while the lower plate remains in a straight extension state to form the extension section 112.

[0032] Accordingly, see Figure 12 and Figure 13The arrangement of the flexible heating film 12 is also different. The flexible heating film 12 includes a third attachment film 123, a fourth attachment film 124, and a fifth attachment film 125. The third attachment film 123 is located between the lower surface of the upper plate and the upper surface of the lower plate, and is attached to the lower surface of the upper plate; the fourth attachment film 124 is located on the upper surface of the upper plate. The third attachment film 123 and the fourth attachment film 124 are staggered in the width direction of the upper plate. On the orthographic projection plane perpendicular to the thickness direction of the upper plate, the projection areas of the third attachment film 123 and the fourth attachment film 124 are connected or overlapped to achieve uninterrupted continuous coverage in the width direction of the upper plate. The fifth attachment film 125 is attached to the lower surface of the lower plate and is used for heating the extension section 112.

[0033] Example 3 See Figure 14 and Figure 15 This embodiment provides a flexible solar array, which includes a roll-up extension mechanism 1 (as a support frame) as described in Embodiment 1 or Embodiment 2, and a flexible battery film 2 laid on the extension sections 112 of two closable extension tubes 11. Before deployment, the entire flexible solar array is as follows: Figure 14 As shown, the entire solar array (including the flexible battery film) is coiled around a roll. When deployment is required, the flexible heating film 12 heats the closable extension tube 11, causing it to return to a cylindrical shape and achieve self-healing closure, serving as the main load-bearing truss of the solar array. The flexible battery film 2 laid within it is smoothly pulled out and flattened along two parallel and spaced extension sections 112 to form a solar power generation surface.

[0034] In this embodiment, the flexible heating film 12 is preferably powered by the power system of the spacecraft on which the flexible solar array is installed, which reduces the system weight, simplifies the structure and improves reliability.

[0035] This embodiment also provides an on-orbit deployment method based on the above-mentioned flexible solar array, including the following steps: Step S1: Thermally driven deployment The spacecraft's power supply drives the flexible heating film 12 to heat up to above the glass transition temperature (Tg) of the self-healing shape memory polymer composite material. At this time, the flattened, rolled-up, and retractable extendable tube 11 softens and releases the internally stored strain energy, utilizing its shape memory effect to return to its initial shape. During this process, the retractable extendable tube 11 drives the flexible battery film 2 laid on the extension section 112 to smoothly unfold and flatten into a solar power generation surface.

[0036] Step S2: Gap Closure and In-situ Self-Healing After the flexible heating film is extended into place, the temperature is maintained or increased to the self-healing activation threshold of the self-healing shape memory polymer composite material (usually slightly above Tg or reaching a specific dynamic bond activation temperature, depending on the material properties) and maintained for a preset time (depending on the material properties, as long as it can support the achievement of self-healing).

[0037] During this stage, the two side walls of the overlap area 111 of the closable extension tube 11 are tightly fitted together, and the dynamic reversible covalent bonds or supramolecular forces inside the material undergo cross-interface diffusion and physical entanglement, causing the opening gap of the overlap area 111 to fuse and close, thereby enabling the closable extension tube 11 to self-heal into a seamless, high-strength closed structure, improving the reliability of the structure during its on-orbit service.

[0038] Step S3: Cooling and curing By stopping the power supply (or reducing the heating power), the material is allowed to cool naturally to the space environment temperature through thermal radiation. The extension tube 11 can be closed to maintain its current deployed state and the opening gaps have healed, thus completing the entire deployment process.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that not every embodiment contains only one independent technical solution, and in the absence of conflict between solutions, the various technical features mentioned in each embodiment can be combined in any way to form other implementation methods that can be understood by those skilled in the art.

[0040] Furthermore, without departing from the scope of the present invention, modifications to the technical solutions described in the foregoing embodiments, or equivalent substitutions of some of the technical features, shall not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A winding extension mechanism based on a self-healing shape memory polymer composite material, characterized in that, include: Two spaced-apart closable extension tubes are provided. The closable extension tubes are made of self-healing shape memory polymer composite material. In the initial form, the wall of the circular tube segment of the closable extension tube has an axially open gap. The opposite sides of the open gap overlap to form an overlap area, and there is a straight extension section on the side of the circular tube segment. The extension sections of the two closable extension tubes are spaced-apart and opposite to each other. A flexible heating film is attached to the surface of the closable and extendable tube. In the flattened and wound storage state, the heating film serves as a physical isolation layer between adjacent tube wall layers to prevent unintended self-adhesion between adjacent tube wall layers when heated. The mounting bracket is located at one end of two spaced-apart closable extension tubes; A reel is installed at the other end of two spaced-apart closable extendable tubes. Before firing, the outer periphery of the reel is wound with the closable extendable tubes in a flattened and stored state and attached with the flexible heating film, serving as a conformal storage base for the closable extendable tubes. During the on-orbit deployment phase, the heating film generates thermal excitation when energized, driving the closable stretchable tube to return from a flattened, wound, and stored state to its initial shape and tightly fitting the opposite sides of the overlapping area. This triggers the dynamic reversible bonds inside the self-healing shape memory polymer composite material to diffuse across the interface and self-heal, thereby closing the opening gap.

2. The winding extension mechanism according to claim 1, characterized in that: During the process of the closable extendable tube returning from the flattened and wound state to its initial form, the overlapping area is located at the junction of the circular tube segment and the extension segment. In the initial form, the closable extendable tube has an asymmetrical cross-sectional configuration, and the circular tube segment and the extension segment are continuously and integrally connected.

3. The winding extension mechanism according to claim 2, characterized in that: The flexible heating film is attached to the surface of the closable stretchable tube. When the closable stretchable tube is in a flattened state, it is in the shape of a stacked plate. The flexible heating film includes a first attachment film and a second attachment film. The first attachment film and the second attachment film are located on the upper and lower surfaces of the stacked plate, respectively, and are staggered along the width direction of the plate. On the orthographic projection plane perpendicular to the thickness direction of the plate, the projection areas of the first attachment film and the second attachment film are connected or overlapped to achieve uninterrupted continuous coverage in the width direction of the stacked plate.

4. The winding extension mechanism according to claim 1, characterized in that: In its flattened temporary state, the closable extendable tube comprises an upper plate and a lower plate. One end of the lower plate is continuously and integrally connected to the lower side of the upper plate, and the remaining portion of the lower plate is arranged parallel to and spaced apart from the upper plate. During the process of restoring from the flattened temporary state to its initial shape, the upper plate curls inward under thermal excitation to form the circular tube segment and the overlapping area, while the lower plate remains in a straight and extended state to form the extended section.

5. The winding extension mechanism according to claim 4, characterized in that: The flexible heating film includes a third attachment film, a fourth attachment film, and a fifth attachment film; the third attachment film is located between the lower surface of the upper plate and the upper surface of the lower plate, and is attached to the lower surface of the upper plate; the fourth attachment film is located on the upper surface of the upper plate; the third and fourth attachment films are staggered in the width direction of the upper plate, and on the orthographic projection plane perpendicular to the thickness direction of the upper plate, the projection areas of the third and fourth attachment films are connected or overlapped to achieve uninterrupted continuous coverage in the width direction of the upper plate; the fifth attachment film is attached to the lower surface of the lower plate.

6. The winding extension mechanism according to claim 1, characterized in that: The outer radius of the closable extension tube ranges from 30mm to 80mm, the wall thickness ranges from 1.5mm to 4.0mm, and the width of the extension section ranges from 20mm to 40mm.

7. The winding extension mechanism according to claim 1, characterized in that: The overlap dimension of the opposite sides of the opening is 1 / 10 to 1 / 12 of the circumference of the circular pipe segment.

8. A flexible solar panel, characterized in that: Including the winding extension mechanism as described in any one of claims 1-7; and Flexible battery membrane laid on the extension sections of the two closable extendable tubes.

9. The flexible solar array according to claim 8, characterized in that: The flexible heating film is powered by the power supply of the spacecraft equipped with flexible solar panels.

10. An on-orbit deployment method based on the flexible solar array as described in claim 8 or 9, characterized in that: Includes the following steps: S1. Thermally driven unfolding step: The power supply drives the flexible heating film to heat up to above the glass transition temperature of the self-healing shape memory polymer composite material, so that the flattened, wound, and stored closable stretchable tube softens and releases internal stress, returning to its initial shape, while driving the flexible battery film laid on its extension section to unfold smoothly. S2, Gap Closure and In-situ Self-Healing Steps: Maintain or continue to raise the temperature of the flexible heating film to above the self-healing activation threshold of the self-healing shape memory polymer composite material and maintain it for a preset time, drive the dynamic reversible covalent bonds or supramolecular forces in the matrix of the self-healing shape memory polymer composite material to undergo cross-interface diffusion and physical entanglement, so that the opening gap of the extension tube is tightly attached and spontaneously fused and closed. S3. Cooling and curing step: Stop the power supply and allow it to cool naturally, so that the closable extension tube locks in the current configuration.

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