KR101652708B1

KR101652708B1 - Reconfigurable deployble tubes with superelastic materials

Info

Publication number: KR101652708B1
Application number: KR1020150082807A
Authority: KR
Inventors: 노진호; 이수용; 권오현; 김진성
Original assignee: 한국항공대학교산학협력단
Priority date: 2015-06-11
Filing date: 2015-06-11
Publication date: 2016-08-31

Abstract

Disclosed is a variable opening type tube using a superelastic material. The variable opening type tube of the present invention comprises a tube body which is hollow inside and a tube extending in the longitudinal direction inside the tube body, And a plurality of stiffeners that are disposed with the stiffener disposed therebetween.

Description

{RECONFIGURABLE DEPLOYABLE TUBES WITH SUPERELASTIC MATERIALS}

The present invention relates to a variable deployment tube using a superelastic material.

Recently, the meteorological environment is rapidly changing around the world, and it is attempted to develop satellites having high performance for precise and rapid prediction of global weather. Specifically, research on ultra-large space structures for advanced satellite mission and maximizing performance has been conducted mainly in developed countries such as the United States, Europe, and Japan.

In particular, the structure technology that develops in space orbit is a core technology required for all space structures such as communication / image opening antenna, solar panel and so on. However, since the conventional unfolded space structure mostly follows the mechanical expansion method, the weight of the expansion device takes a relatively large proportion, and the deployment mechanism parts may occupy 90% or more of the total structure.

According to such a conventional mechanical expansion method, excessive weight problems and a problem of securing a storage space existed. To cope with such problems, enormous research and development costs were forced to be put into. The background technology of the present application is disclosed in Korean Patent Laid-Open Publication No. 2011-0133756.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the problems of the prior art described above and to provide a variable expansion type tube that can be folded into a small volume that can be accommodated in a small space and uses a superelastic material that can be deployed without additional mechanical devices do.

The present invention also provides a variable deployment tube using a superelastic material that can be repeatedly accommodated and deployed.

The present invention also provides a variable deployment type tube made of a thin composite material excellent in non-rigidity and non-rigidity so that an additional expansion device is not required, and which is light in weight and can be carried and moved freely using a super elastic material.

The present invention also provides a variable expansion type tube using a superelastic material, which can control the speed and shape of the self-expanding shape by controlling the temperature of the shape memory polymer composite material.

The present invention also provides a variable deployment type tube using a superelastic material capable of improving durability and reliability in a space environment.

It is to be understood, however, that the technical scope of the present invention is not limited to the above-described technical problems, and other technical problems may exist.

According to an aspect of the present invention, there is provided a variable expansion type tube using a super elastic material, the tube including a hollow tube body and a tube body extending in the longitudinal direction in the tube body, And a plurality of stiffeners disposed at intervals along the circumference of the tube body.

According to one example of this embodiment, the plurality of stiffeners may have a pair arranged in mutually symmetrical manner when viewed in cross section.

According to an example of this embodiment, the stiffener may be a wire having a superelastic material.

According to one example of this embodiment, the super elastic material may be a material including shape memory alloys.

According to one embodiment of the present invention, the super elastic material may be a material having elastic restoring force that is easily deformed without damage and residual deformation of the material corresponding to the external force, and is restored to the shape before the deformation.

According to one embodiment of the present invention, the tube body may be made of a material including a TWF (Triaxially Woven Fabric Silicon) including TWF carbon fiber and silicone resin.

According to one example of this embodiment, a capton film may be formed on the surface of the tube body.

According to one embodiment of the present embodiment, the cross-sectional surface may be formed in a shape, and the shape memory member may be disposed inside the tube body so as to extend in the longitudinal direction.

According to an embodiment of the present invention, the shape memory member includes an upper flange and a lower flange, which are disposed so as to be in contact with the inner circumference of the tube body and spaced apart from each other by a predetermined distance, . &Lt; / RTI >

According to one example of this embodiment, the upper flange or the lower flange and the web may be at right angles to each other.

According to the example of this embodiment, the plurality of stiffeners may be provided in an area where the upper and lower flanges of the shape memory member are not disposed.

According to an example of this embodiment, the shape memory member may further include a heat unit for providing a predetermined heat.

According to one example of this embodiment, the heat unit may include a heat line that is placed in contact with at least one of upper and lower flanges and webs of the shape memory member, and a power source unit that is electrically connected to the heat line.

According to an example of this embodiment, the heat unit may include carbon nanotube particles included in the shape memory member.

According to an embodiment of the present invention, the carbon nanotube particle can heat the shape memory member by a microwave provided from the outside.

The above-described task solution is merely exemplary and should not be construed as limiting the present disclosure. In addition to the exemplary embodiments described above, there may be additional embodiments described in the drawings and the detailed description of the invention.

According to the above-described task solution of the present invention, it is possible to fold in a compact shape (volume) that can be stored in a small space, and it is possible to self-expand according to need without using a mechanical expansion structure, The storage efficiency can be greatly improved and the development system can be simplified by the self development method, so that the manufacturing cost can be reduced and the reliability in the development process can be greatly improved.

In addition, high torsional rigidity can be ensured through the tube structure, and by combining the tube structure with the stiffeners arranged along the circumference of the tube structure, the moment of inertia can be maximized and high bending rigidity can be ensured.

In addition, the present invention is made of a thin film composite material excellent in non-strength and non-rigidity so that an additional expansion device is not necessary, so that it is light in weight and can be carried and moved freely.

Further, by using the shape memory member which has the characteristic of super elasticity that can be easily deformed at a predetermined temperature or more and can be restored to the initial shape, it is possible to control the self-developed speed and shape through temperature control on the shape memory member .

Further, by forming a capton film coated with aluminum on the surface of the tube body, it is possible to shield the UV in a space environment and prevent extreme temperature changes, thereby improving durability and reliability.

Further, the effects obtainable here are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the following description will be.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a view of a variable deployment tube using a superelastic material according to one embodiment of the present invention.
FIG. 2 is a developed view of a variable deployment type tube using a folded super elastic material. FIG.
3 is a view showing a variable expansion type tube using a superelastic material including a shape memory member.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. It should be understood, however, that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In the drawings, the same reference numbers are used throughout the specification to refer to the same or like parts.

Throughout this specification, when a part is referred to as being "connected" to another part, it is not limited to a case where it is "directly connected" but also includes the case where it is "electrically connected" do.

Throughout this specification, when a member is "on " another member, it includes not only when the member is in contact with the other member, but also when there is another member between the two members.

Throughout this specification, when an element is referred to as "including " an element, it is understood that the element may include other elements as well, without departing from the other elements unless specifically stated otherwise.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a view of a variable deployment tube using a superelastic material according to one embodiment of the present invention.

As shown in FIG. 1, the variable deployment tube 100 using a superelastic material may include a tube body 10.

The variable opening type tube 100 using the super elastic material can withstand a high strain and can restore the initial shape after deformation due to the elastic restoring force.

The variable opening type tube 100 using the super elastic material can be applied to an expansion type large space structure (Antenna, .Refletor, Solar array, etc.), contributing to weight reduction of a space expanding structure. Also, the deployable tube 100 can be applied to a small portable tent and ground antenna.

The variable expansion type tube 100 using such a super elastic material can be applied as a source technology for the development of ultra-large and lightweight space structures, and the weight can be reduced to 1/00 level compared to conventional space structures, It is possible to reduce the development cost of the space structure to 1/10 or less by reducing the storage efficiency and the launching cost.

Hereinafter, the structure of the variable expansion tube 100 using the superelastic material will be described in detail.

Referring to FIG. 1, a variable deployment tube 100 using a superelastic material may include a tube body 10.

The tube body 10 may be formed in a tube shape. Here, the tube shape may mean a hollow cylinder shape or a pipe shape. At least one of both ends of the tube body 10 may be opened. In addition, the tube body 10 may be provided in the form of an ultra-thin skin so that the variable-expansion tube 100 can be folded or wound as compact as possible (see FIG. 2) have.

The tube body 10 may be a material including a TWF (Triaxially Woven Fabric Silicon) mixed with a TWF (Carbon Fiber Woven Fabric) carbon fiber and a silicone resin. Illustratively, the tube body 10 can be made of a boom structure having a circular (including elliptical) cross section, using an ultra thin skin having a predetermined thin thickness.

TWFS has the property of superelasticity that it can withstand high strain without damaging the material and restore the initial shape after deformation by elastic restoring force. By combining the tube main body 10 with the stiffener 30 disposed along the circumference of the tube main body 10, folding for accommodating the external force is easy, and when there is no external force, And a deformable tube 100 that can have a predetermined torsional stiffness and bending stiffness after the shape restoration can be provided.

Also, a capton film (not shown) coated with aluminum may be formed on the surface of the tube main body 10. Capton film can improve the durability and reliability of the developed tube 100 by shielding UV and preventing extreme temperature changes in a space environment.

Further, the variable deployment type tube 100 using a super elastic material may include a plurality of stiffeners 30.

The plurality of stiffeners 30 may be arranged to extend in the longitudinal direction of the tube body 10 and be spaced apart along the circumference of the tube body 10. [ Further, the plurality of stiffeners 30 may have a rod shape. The stiffener 30 is arranged around the tube body 10 to reinforce the tube body 10 at the maximum distance from the center of the tube body 10 so that a high moment of inertia can be secured, A plurality of stiffeners 30 may be disposed along the inner periphery of the tube body 10. [

And the plurality of stiffeners 30 may have a pair disposed in mutually symmetrical relationship when viewed in cross section. 1, the plurality of stiffeners 30 may be arranged symmetrically or vertically symmetrically to form a pair of two stiffeners 30. However, the present invention is not limited to this, and a desired bending stiffness Are arranged in such a number that they can be ensured.

The plurality of stiffeners 30 may be wires having a superelastic material. Superelasticity means the property of returning to the shape before deformation without damage and residual deformation of the material even after large deformation. Such a superelastic material may also be a material containing a shape memory material such as shape memory alloys. When the plurality of stiffeners 30 are made of a material containing a shape memory material, the plurality of stiffeners 30 can easily deform when the external force is applied and return to the initial shape when no external force is applied . The superelastic characteristics by the shape memory material can be understood from the description of the shape memory member 20 to be described later.

As described above, according to the present invention, by organically combining a plurality of stiffeners 30 formed of wires of super-elastic material and a tube structure of a thin film having a super elastic property, the torsional rigidity and the bending rigidity Can be improved.

FIG. 2 is a developed view of a variable deployment type tube using a folded super elastic material. FIG. As shown in FIG. 2, the variable expansion type tube 100 using the folded super elastic material has an initial elasticity due to the elastic restoring force of the tube body 10 and the stiffener 30, Can be deployed on its own.

It is preferable that the plurality of stiffeners 30 are disposed in the region of the tube main body 10 where the upper and lower flanges 21 (the upper flange and the lower flange) of the shape memory member 20 to be described later are not disposed.

3 is a view showing a variable expansion type tube using a superelastic material including a shape memory member. As shown in FIG. 3, the deformable tube 100 using a super elastic material may include a shape memory member 20.

The shape memory member 20 is formed in a shape of a cross section and can be disposed in the tube body 10 in a longitudinal direction. More specifically, the shape memory member 20 includes upper and lower flanges 21 disposed to face the inner circumference of the tube main body 10 so as to face each other with a predetermined distance therebetween, a web 21 connecting the upper and lower flanges 21, (22).

At this time, the upper and lower flanges 21 and the web 22 may be arranged at right angles to each other. Also, the webs 22 can interconnect the middle of the upper and lower flanges 21 (center in FIG. 1).

In addition, the upper and lower flanges 21 may have a thickness and a protruding length such that the tube body 10 has a thickness equal to or less than a predetermined thickness and can be bent (or wound). Here, the thickness of the upper and lower flanges 21 means the thickness in the vertical direction of FIG. 1, and the protruding length of the upper and lower flanges 21 means the length protruding in the left-right direction with respect to the web 22. Further, the upper and lower flanges 21 may be provided to have a thickness and a protruding length capable of securing predetermined bending rigidity. That is, the upper and lower flanges 21 preferably have a thin thickness or a short protruding length in terms of compact bending (or winding), but have a thick thickness and a long protruding length in terms of ensuring a predetermined bending rigidity desirable. Therefore, the upper and lower flanges 21 can be designed to have appropriate thicknesses and protruding lengths in consideration of both sides.

The shape memory member 20 may be made of a material including a Shape Memory Polymer Composite (SMPC) in which WF (Woven Fabric) carbon fiber and SMP resin are mixed.

For reference, a shape memory polymer (SMP) is a polymer that stores an initial shape and returns to its original shape from a deformed shape when the temperature exceeds a glass transition temperature. The mechanism to restore strain is a change in entropy resulting from the elasticity of the shape memory polymer. The molecular structure of the shape memory polymer is similar to the network structure, and the cross-link molecular chains and reversible molecules connecting the molecular structures are complex. The molecular chain serves as a non-reversible phase that can not go back once it is cured and prevents free movement.

On the other hand, the reversible phase takes a large part in the shape memory polymer and plays an elastic role in deformation and recovery. When the temperature exceeds a certain temperature, the reversible phase becomes fluid and flowability is improved. This temperature is called the glass transition temperature (Tg). When the external force is applied above the glass transition temperature, the molecular chains of the shape memory polymer are aligned and the entropy is reduced. At this time, when the temperature is rapidly lowered to below the glass transition temperature, the unstable reversible phase is stabilized again and the modified form is maintained.

In addition, if heat is applied at a temperature above the glass transition temperature, the molecular chains move through the stored strain energy and return to the original shape.

The thermo-mechanical properties of shape memory polymers change with temperature and time. That is, there is a temperature dependent shape memory effect (SME: Shape Memory Effect) and time-dependent viscoelasticity characteristic.

The shape memory polymer composite material (SMPC) including the shape memory polymer has a superelasticity elastic restoring force capable of large deformation due to a very low rigidity of the material at a specific temperature (Tg) or higher and restored to its initial shape, And has a characteristic of storing the shape before deformation.

A manufacturing process of the shape memory polymer composite material (SMPC) will be described below as an example.

Shape memory polymer (SMP) is made of polyurethane material and DiALEX MP4510 / MP5510 of Mitsubishi Heavy Industries, Ltd. can be used. The resin and the curing agent are mixed and cured in a weight ratio of 2: 3.

The carbon fiber may be T-300 class woven fabric manufactured by Toray Co., Ltd. of Japan. The carbon fiber is laminated in a mold, the mixed shape memory polymer is poured on it, and a vacuum pressure is applied to induce the shape memory polymer to be impregnated into the entire fiber.

While holding the vacuum pressure, put in an oven and cure at 70 ° C for 2 hours. At this time, since the curing rate of the SMPC is very fast within 3 minutes, bubbles are generated on the surface or a solidification phenomenon occurs. Therefore, the process must be changed so that the air bubbles can pass through the fibers.

A breather that uniformly distributes vacuum pressure was attached to the side of the carbon fiber. The liquid shape memory polymer was poured on the carbon fiber and pushed to the breather by the rubber stopper to prevent the occurrence of the core. Thus, a more stable state of the synthetic memory polymer composite material can be produced, which has a function of absorbing surplus resin by making a path to escape of bubbles.

In addition, by impregnating carbon nanotubes (CNTs) in the synthetic memory polymer, the temperature of the synthetic memory polymer can be controlled by using a micro-wave.

On the other hand, the shape memory member 20 may have an initial shape extending along the longitudinal direction of the tube main body 10. Further, the shape memory member 20 can have a superelastic elastic restoring force capable of large deformation and being restored to its initial shape at a temperature equal to or higher than a preset temperature. Further, the shape memory member 20 may have a stiffness lower than a predetermined stiffness at a temperature lower than a predetermined temperature so as to be deformed by an external force applied at a predetermined temperature or higher. That is, the shape memory member 20 can be easily deformed in response to an external force that is lowered in rigidity at a temperature equal to or higher than a preset temperature, and can have an elastic restoring force to restore the initial shape.

Then, at the temperature lower than the preset temperature, the elastic restoring force of the shape memory member 20 may be lost.

That is, the shape memory member 20 easily deforms at a predetermined temperature or higher, and when the temperature is lowered, the deformed shape can be maintained without being restored to the initial shape. The shape memory member 20 can be returned to the shape before the deformation (initial shape) if the temperature is raised to a predetermined temperature or more.

The shape memory member 20 has a low rigidity capable of being folded into an arbitrary shape at the time of external force application at a temperature equal to or higher than a preset temperature, and can be automatically expanded to an initial shape if there is no external force.

FIG. 2 is a developed view of a variable deployment type tube using a folded super elastic material. FIG. Referring to FIG. 2, the bendable deformable tube 100 can be automatically deployed to its initial shape without additional external force, while exhibiting elastic elastic restoring force characteristics at a temperature higher than a preset temperature.

On the other hand, the variable expansion tube 100 using a super elastic material may include a heat unit (not shown).

The heat unit can provide a predetermined heat to the shape memory member 20. The heat unit may include a heat source (not shown) and a power source (not shown) electrically connected to the heat line, which are disposed in contact with at least one of the upper and lower flanges 21 and the web 22 of the shape memory member 20 . The power supply unit may be provided at any one of the opposite ends of the tube main body 10.

As the heat is supplied to the shape memory member 20 through the above-described heat ray and the power source portion, the development speed and shape of the shape memory member 20 can be controlled through temperature regulation.

Also, as another embodiment of the heat unit, the heat unit may be a carbon nanotube (CNT) particle contained in the shape memory member 20. In this case, the carbon nanotube particle can raise the temperature of the shape memory member 20 by the microwave provided from the outside. According to this, the heat unit may include a microwave generating apparatus that generates a microwave applied to the carbon nanotube particles.

It will be understood by those of ordinary skill in the art that the foregoing description of the embodiments is for illustrative purposes and that those skilled in the art can easily modify the invention without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed in a similar fashion may also be implemented.

The scope of the present invention is defined by the appended claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

100: Variable expansion tube using ultra-elastic material
10: tube body
20: Shape memory member
30: Stiffener

Claims

As a variable expansion type tube using a super elastic material,
A tube body having a hollow interior;
A plurality of stiffeners extending in the longitudinal direction within the tube body, the plurality of stiffeners being spaced along the circumference of the tube body; And
And a shape memory member having a cross section formed in an I-shape and extending in the longitudinal direction within the tube body,
Wherein the stiffener is a wire having a superelastic material.

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The method according to claim 1,
Wherein the superelastic material comprises shape memory alloys.

The method according to claim 1,
The ultra-elastic material may be,
Wherein the deformable tube is made of a material having elastic restoring force that is easily deformed without damage and residual deformation of the material in response to an external force and restored to the shape before the deformation.

The method according to claim 1,
Wherein the tube body is made of a material comprising a TWF (Triaxially Woven Fabric Silicon) including TWF carbon fibers and a silicone resin.

The method according to claim 1,
And a capton film is formed on the surface of the tube body.

delete

The method according to claim 1,
The shape memory member
An upper flange and a lower flange disposed to face the inner circumference of the tube body and disposed to face each other with a predetermined distance therebetween; And
And a web connecting said upper flange and said lower flange.

10. The method of claim 9,
Wherein the upper flange or the lower flange and the web are at right angles to each other.

9. The method of claim 8,
Further comprising a heat unit for providing a predetermined heat to the shape memory member.

12. The method of claim 11,
The thermal unit may include:
A heat wire arranged in contact with at least one of an upper flange, a lower flange and a web of the shape memory member; And
And a power supply unit electrically connected to the heat line.

12. The method of claim 11,
Wherein the heat unit includes carbon nanotube (CNT) particles included in the shape memory member.

14. The method of claim 13,
Wherein the carbon nanotube particles are heated by a microwave provided from the outside to increase the temperature of the shape memory member.