Compactible structure for deployment in space

Abstract

The systems and methods described herein include foldable and deployable antenna structures that can include any combination of shape memory composites, expandable envelopes, and / or degradable materials.

Description

[Technical Field]

[0001] This application claims priority to U.S. Provisional Patent Application No. 63 / 091,918, entitled "Compactable Structures for Deployment in Space," filed October 14, 2020, which is incorporated herein by reference in its entirety. [Background technology]

[0002] Space structures must balance several functional attributes. For example, the stronger a material is, the longer it can last in space or the easier it can be deployed without failure. However, the heavier and larger the object can be, the exponentially increasing the cost of launching the object into space.

[0003] Space structures may also be limited in their design or material composition due to environmental conditions and changes imposed on the deployment of objects into space and / or their own deployment conditions. For example, an article for space deployment must transition through different environments. It may also be desirable to be able to deploy articles of any size. There may be various methods for deploying an object. The deployment of an object from a stowed state to a deployed or use state imposes forces and stresses on the object that may limit the materials of construction and / or the shape, size, orientation, configuration, and combinations thereof, of the deployed object.

[0004] Therefore, typical antennas for space applications are rigid structures made of conductive metals. The nominal size of the antenna is traditionally on the order of the radio waves being received, which can be on the order of 10–15 centimeters for S-band frequencies. This is the size of a typical U CubeSat, which must also include electronics, cameras, power sources, and other components. This poses logistical challenges for satellites that are preferably stowed during launch and deployed in orbit. Given their material construction limitations, such stowable configurations of conventional antennas are difficult. As a result, antennas used for small satellites are usually extremely limited in size. Therefore, the antenna's beam pattern may be compromised or narrowed to reduce size. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] US Patent Application Publication No. 2016 / 0288453 Summary of the Invention [Means for solving the problem]

[0006] The antennas and satellites described herein may include satellite-based structures. The satellite-based structures may be any desired object for use in space, such as an antenna and / or a solar sail. Any space structure may be within the scope of the present disclosure.

[0007] Exemplary embodiments include a satellite structure that is deployable from a stowed configuration to a deployed configuration. Exemplary embodiments of the satellite structure may include materials that allow bending or that allow the satellite structure to maintain the same shape in the stowed configuration, e.g., allow creep. Exemplary embodiments of the satellite structure may include materials and / or structural shapes (including sizes) that are insufficiently strong to withstand deployment forces from the stowed configuration to the deployed configuration.

[0008] Exemplary embodiments include a degradable layer (either as a bottom layer and / or a top layer) for covering the satellite base structure. The degradable layer can comprise a layer that is degradable in external space, such as upon contact with atomic oxygen and / or radiation. The degradable layer can be sufficiently strong, alone and / or in combination with the substrate layer and / or satellite base structure, to withstand deployment from a stowed configuration to a deployed configuration.

[0009] Thus, exemplary embodiments may include a method in which the degradable layer is configured to degrade once exposed to a degradable environment. In exemplary embodiments, the degradable layer degrades to expose the satellite base structure. In exemplary embodiments, the degradable layer may be used to protect and / or assist the satellite base structure until it is deployed to the deployed configuration.

[0010] Although the exemplary embodiments described herein are described in terms of using degradable layers to aid in deployment, degradable layers can be used for other purposes as well. In exemplary embodiments, the degradable layers can be degraded in space to reduce the mass of the system after deployment. The degradable layers can be used to protect and / or hold the satellite base structure in a desired configuration. In exemplary embodiments, the degradable layers can be used to hold the satellite base structure to a substrate layer. In exemplary embodiments, the substrate layer can also be degradable.

[0011] In an exemplary embodiment, a system including a satellite base structure is in a storage configuration. The satellite base structure can include a housing. The housing can protect the satellite base structure and / or hold the base structure in the storage configuration. The housing can reduce contact of the degradable layer with a degradative environment while in the storage configuration, such that the degradable layer does not degrade or the rate of degrading is reduced.

[0012] An exemplary embodiment includes a satellite base structure and an antenna made of degradable layers. The exemplary embodiment allows for transition of the antenna from a deformed, stowed configuration to a deployed configuration. The deformed configuration may be a folded configuration or may otherwise define a smaller dimension or volume for storage or transport. In the exemplary embodiment, the satellite base structure may be transformable between a stored configuration and a deployed configuration.

[0013] Exemplary embodiments may include a satellite base structure comprising a gossamer thin film, the satellite base structure may comprise a mesh foil, the satellite base structure may comprise a foil, or the satellite base structure may comprise a conductive material.

[0014] Exemplary embodiments may include a shape memory composite material. The shape memory composite material may include a conductive material to act as an antenna. The shape memory composite material may be made conductive through material selection of the fibers, resins holding the fibers, additives to the fibers and / or resin, coatings, and other methods described herein. The fibers may be conductive. The resin may be conductive. Metal or conductive powders, additives, or fillers may be added to the resin or fillers between the fibers. Metal strands may be incorporated with or used exclusively as composite fibers. Thin metal foils may be coated or used to cover all or part of a member made from a shape memory composite material. Conductive paint or other coatings may be applied to all or part of the surface of a component made from a shape memory composite material. Exemplary embodiments of shape memory composite structures for use as antennas are disclosed in PCT / US2020 / 48848, filed August 31, 2020, which is incorporated herein by reference in its entirety. Exemplary embodiments of degradable layers may be used as substrates and / or in combination with substrates and / or the described shape memory composites. Thus, degrading the degradable layer may be used to aid in the deployment of the shape memory composite, which may then be degraded, reducing the weight of the antenna after deployment and / or reducing / eliminating interference with the antenna. [Brief explanation of the drawings]

[0015] [Figure 1] 1A-1C illustrate example antenna shapes according to embodiments described herein. [Figure 2] 1A-1C illustrate example antenna shapes according to embodiments described herein. [Figure 3] 1A-1C illustrate example antenna shapes according to embodiments described herein. [Figure 4]1A-1C illustrate example antenna configurations according to embodiments described herein, including an envelope that may include a degradable layer. [Figure 5] 1A-1C illustrate example antenna configurations according to embodiments described herein, including an envelope that may include a degradable layer. [Figure 6] 1A-1C illustrate example antenna configurations according to embodiments described herein, including an envelope that may include a degradable layer. [Figure 7] 1A-1C illustrate example antenna configurations according to embodiments described herein, including an envelope that may include a degradable layer. [Figure 8] 1A-1C illustrate example antenna configurations according to embodiments described herein, including an envelope that may include a degradable layer. [Figure 9] 1A-1C illustrate example antenna configurations according to embodiments described herein, including an envelope that may include a degradable layer. [Figure 10] 1A-1C illustrate example antenna configurations according to embodiments described herein, including an envelope that may include a degradable layer. [Figure 11A] 1A-1C illustrate an exemplary deployment sequence according to embodiments described herein. [Figure 11B] 1A-1C illustrate an exemplary deployment sequence according to embodiments described herein. [Figure 11C] 1A-1C illustrate an exemplary deployment sequence according to embodiments described herein. [Figure 12] FIG. 1 illustrates an exemplary configuration according to embodiments described herein. [Figure 13A] 1A-1C illustrate an exemplary deployment sequence according to embodiments described herein. [Figure 13B] 1A-1C illustrate an exemplary deployment sequence according to embodiments described herein. [Figure 13C] 1A-1C illustrate an exemplary deployment sequence according to embodiments described herein. [Figure 14] FIG. 1 illustrates an exemplary system according to embodiments described herein. DETAILED DESCRIPTION OF THE INVENTION

[0016] The following detailed description illustrates the principles of the present invention by way of example, not by way of limitation. This description clearly enables any person skilled in the art to make and use the invention, and describes several embodiments, adaptations, modifications, alternatives, and uses of the invention, including what is presently believed to be the best mode for carrying out the invention. It should be understood that the drawings are diagrammatic and provide schematic representations of example embodiments of the invention and are not limiting of the invention, and that the drawings are not necessarily drawn to scale.

[0017] Exemplary embodiments may use a satellite base structure. The satellite base structure may comprise a metallic material, a conductive material, and / or a reflective material. The satellite base structure may be configured in a deployed configuration as an antenna, a solar sail, a reflector, or other space structure. The satellite base structure may comprise a material and / or a shape to achieve a purpose in space. In exemplary embodiments, the satellite base structure may be insufficiently strong (due to material selection and / or shape, size, orientation, etc.) for deployment from a stowed configuration to a deployed configuration through a desired deployment mechanism. In exemplary embodiments, the satellite base structure may be insufficiently shaped (due to magnetic permeability, shape, size, orientation, aperture, etc.) for deployment from a stowed configuration to a deployed configuration through a desired deployment mechanism. The deployment mechanism may be, for example, inflation. The deployment mechanism may be through an extension system that imposes a tensile force and / or a compressive force on the satellite base structure. The deployment mechanism may comprise unfolding the satellite base structure.

[0018] Exemplary embodiments may use dynamically deformable materials as support and deployment structures to support a satellite base structure. In exemplary embodiments, the satellite base structure comprises electrically conductive material to create an antenna configuration geometry. In exemplary embodiments, the dynamically deformable material may include electrically conductive material to create the antenna configuration. In exemplary embodiments, the dynamically deformable material may not include electrically conductive material, but may support an electrically conductive material in a desired configuration.

[0019] Exemplary embodiments may use an envelope contained within and / or supported by the satellite base structure. The envelope may be gas impermeable or semi-gas impermeable to allow expansion during deployment of the antenna. The envelope may be expanded to assist the antenna in transitioning to a deployed configuration. The envelope may be expanded to release the antenna from a stowed configuration. The envelope may act as a substrate to support electrically conductive material for creating the antenna configuration. The envelope may comprise a degradable material.

[0020] Exemplary embodiments may include a degradable layer disposed on the satellite base structure. The degradable layer may be used in combination with an envelope or alone. The degradable layer may be disposed on the satellite base structure to provide structural support and / or strength to the satellite base structure during deployment. Thus, the degradable layer may be a coating on all or a portion of the satellite base structure. The degradable layer may be a layer on all or a portion of the envelope (if present). The degradable layer may be a layer around the perimeter of the exterior surface defined by or created by all or a portion of the satellite base structure in the deployed configuration. In exemplary embodiments, the degradable layer is capable of dynamic deformation.

[0021] Although embodiments of the present invention may be described and illustrated herein in terms of particular antenna configurations, it should be understood that embodiments of the present invention are not limited thereto and may also be applicable to different antenna configurations.

[0022] While the exemplary embodiments are shown and described with respect to creating an omnidirectional antenna for free-space communications between a ground station and another spacecraft, other applications are within the scope of this disclosure. For example, directional antennas are within the scope of this disclosure. Other uses are also within the scope of this application, not just space communications between spacecraft. The exemplary embodiments also disclosed include different combinations and configurations of satellite-based structures that can be used for different purposes, such as solar sails. In this configuration, the satellite-based structures can comprise flat structures and / or sheets, grids, or other structures for reflecting solar energy and creating drag.

[0023] Any feature, component, configuration, and / or attribute described with respect to any one example may be used in combination with any other example. Thus, any step, feature, component, configuration, and / or attribute may be used in any combination and still be within the scope of the description. Features may be removed, added, duplicated, merged, subdivided, or otherwise recombined and still be within the scope of the description. The exemplary embodiments described herein are provided for example purposes only. Thus, any satellite-based structure may be used with or without an envelope according to the embodiments described herein. Any satellite-based structure may be used with or without a tear-off or breakaway retention device according to the embodiments described herein. Any satellite-based structure may be used with an inflation mechanism according to the embodiments described herein.

[0024] 1-10 illustrate exemplary antenna configurations according to embodiments described herein. In exemplary embodiments, the antenna structures 10, 20, 30, 40, 50, 60, 70, 80, 90, 100 may comprise a gossamer film, foil, or other material or size insufficient to reliably withstand deployment of the antenna structure from a stored configuration to a deployed configuration. Exemplary embodiments may comprise a satellite base structure 12, 22, 32, 42, 52, 62, 72, 82, 92, 102. The satellite base structure may be deformable to allow folding of the antenna under the application of an external force. Thus, the folded configuration may be dynamically determined based on the storage compartment or the applied external force. For example, the satellite base structure may be flexible or deformable along a length when a force is applied. In exemplary embodiments, the satellite base structure may flex at one or more locations around or along the structure. In an exemplary embodiment, the satellite-based structure can have a deployed shape that, once deployed, is maintained without the use of an external force. The predefined shape can be defined through relationships and connections with one or more other support structures, such as the envelope or shape-memory composite material described herein.

[0025] An exemplary embodiment includes a satellite base structure. An exemplary embodiment includes a support structure. The support structure includes a layer disposed on the satellite base structure, or on all or a portion of the satellite base structure. The support structure can include a degradable layer on all or a portion of the satellite base structure. The degradable layer can be configured to support the satellite base structure during storage and / or deployment. The degradable layer can then be configured to degrade and separate from the satellite base structure after degradation.

[0026] FIG. 1 illustrates an exemplary embodiment of an antenna configuration 10 in which a conductive material is configured as a quadrifilar (four helical conductor) helical antenna. As shown, the antenna structure includes a satellite base structure 12 comprising conductors. The conductive member defines four helical strands wrapped around a central longitudinal axis. The central longitudinal axis may include a conductive shaft. Opposite ends of the quadrifilar may include radial extensions connecting the individual helical strands to the longitudinal axis or central shaft at the opposite ends of the individual helical strands. The helical strands may be circumferentially offset by 90 degrees. The helical strands and the central shape may be made of a shape memory composite, allowing the entire structure to deform and flex in any unstructured or random configuration to fit within a desired storage space. Portions of the helical strands and / or the central portion may be made of a shape memory composite.

[0027] FIG. 2 illustrates an exemplary embodiment of an antenna configuration 20 defining a biconical antenna. As shown, the antenna may include a hub 24. Extending from opposite sides of the hub along the center of the antenna is a longitudinal axis defined for reference. A conductive shaft may be aligned with the longitudinal axis. As shown, five conductive members extend radially, extending longitudinally away from the hub on either side of the hub. The five members may extend radially outward a certain distance and then extend radially inward toward the longitudinal axis to couple to the shaft. The radially inward extending portions of the conductive members may extend only radially inward, such that the conductive members define a portion of a right triangle. Additionally, the conductive members may continue to extend longitudinally away from the hub as they extend radially inward, thus defining other curved, angled, or triangular shapes.

[0028] FIG. 3 illustrates an exemplary antenna configuration 30. Conductive material, as described herein, may be present within a satellite base structure 32. The conductive material may define one or more rectangular, square, quadrilateral, or other geometric shapes. These shapes may be arranged such that the plane of the shape includes or passes through the longitudinal axis of the antenna configuration defined for reference. These shapes may be circumferentially offset and arranged circumferentially around the longitudinal axis. Conductive shafts may be aligned with and / or define the longitudinal axis.

[0029] 4-10 illustrate exemplary antenna configurations according to embodiments described herein, including an envelope. The exemplary embodiments shown illustrate exemplary embodiments of the support structure described herein with dashed lines. The support structure is shown with different types of lines to distinguish between component parts for illustrative purposes and to improve understanding of the invention. The dashed lines are not intended to suggest or represent holes or apertures in the support structure, although the support structure may include such features. In exemplary embodiments, the support structure is gas impermeable as described herein.

[0030] In exemplary embodiments, the antenna structures 40, 50, 60, 70, 80, 90, 100 may be supported by support structures 46, 56, 66, 76, 86, 96, 106. The support structures 46, 56, 66, 76, 86, 96, 106 may be conductive or non-conductive. The support structures may provide other features for the antenna, such as shape support, signal effect, directional effect, storage retention, deployment actuation, or a combination thereof. In exemplary embodiments, the support structures comprise a flexible membrane. Thus, the support structures may be foldable and / or deformable in the same or similar manner as the antenna structures. The support structures may be dielectric membranes. The support structures may be fabrics, meshes, or sheets. The support structures may be Kapton, Mylar, Teflon, cotton, or other dielectric and / or non-conductive materials. Although shown as included with only a subset of exemplary embodiments, the support structures may be used with any antenna configuration described herein. The support structure may be coupled to the shape memory composite material, the conductive component, other components of the antenna, or a combination thereof.

[0031] In exemplary embodiments, the support structures 46, 56, 66, 76, 86, 96, 106 define a thin surface. The support structures 46, 56, 66, 76, 86, 96, 106 may include flexible materials coupled to other additional support structures, any combination of support structures, shape memory composite components, and / or conductive components. In exemplary embodiments, the support structures 46, 56, 66, 76, 86, 96, 106 define a gas-impermeable or semi-gas-impermeable surface. The support structures may be envelopes for defining an internal cavity. The support structures may be arranged to create a continuous gas-impermeable surface around the internal cavity. In exemplary embodiments, the support structures may be inflatable, as described more fully herein. In exemplary embodiments, the support structures may be inflatable to aid in the deployment of the antenna structures. The support structure may be configured to allow inserted fluid to vent after inflation and / or may be configured to retain fluid for a period of time after inflation. Thus, a gas-impermeable surface may include a surface that retains enough gas to assist in deployment and initial inflation, but allows the gas to vent thereafter. A gas-impermeable surface may be configured to retain enough gas for a desired amount of time, which may be longer than initial deployment and inflation, while still including a surface that vents over time.

[0032] In an exemplary embodiment, the support structure comprises a degradable material. Thus, the support structure may be configured to degrade after deployment of the satellite base structure. In an exemplary embodiment, the degradation may range from approximately one to five days. In an exemplary embodiment, the degradable material comprises a degradable polymer. For example, the degradable material may be Mylar, polyester, Kapton, polystyrene, or combinations thereof. In an exemplary embodiment, the degradable material is configured to degrade in the presence of atomic oxygen. In an exemplary embodiment, the degradable material is configured to degrade in the presence of solar radiation.

[0033] Figures 4-6 show exemplary configurations in which satellite base structures 42, 52, 62 are disposed within layers of support structures 46, 56, 66. Figure 4 shows an exemplary circular cylindrical support structure 46 having one spiral conductive element 42. Other spiral structures may be added to the support structure (as shown in Figure 1). Figure 5 shows an exemplary circular conical support structure 56 having one spiral conductive element 52 bonded to the support structure such that the diameter of the spiral conductive element tapers from one end of the antenna to the opposite end. The conical support structure may come to a point or may terminate at a smaller diameter end before coming to a point. Other spiral or patterned structures may also be added to the support structure.

[0034] Exemplary embodiments can also use combinations of dielectric and / or non-conductive layers to create composite antenna configurations with leads that may overlap each other but may or may not be in contact with each other. For example, a first cylindrical support structure can be used with conductive material, either on its interior and / or exterior surfaces. A second cylindrical support structure can be disposed on or inside the first cylindrical support structure, enclosing the conductive material between the first and second layers. The other side of the second cylindrical support structure, opposite the side in contact with the enclosed conductive material, can also include conductive material. Thus, an antenna can include a first conductive layer, a non-conductive and / or dielectric layer defining a first pattern, and a second conductive layer defining a second pattern. The antenna can include additional combinations of conductive and non-conductive and / or dielectric layers. Different layers can be used to create composite antenna configurations and to create different conductive patterns that can be electrically coupled and / or electrically isolated.

[0035] FIG. 6 illustrates an exemplary configuration having multiple support structures 66 and conductive members 62. As shown, different antenna shapes can be created. As can be seen in FIG. 6, the first antenna-shaped portion defines multiple radially extending conductive elements 62A. The second antenna-shaped portion defines multiple radially and longitudinally extending conductive elements 62B, creating a generally conical configuration. The first support structure can define a generally cylindrical shape, while the second support structure can define a generally conical shape. Each of the conductive elements can be coupled to a surface of the support structure. The support structures can define separate volumetric cavities. The support structure cavities can be connected or isolated. The volumetric cavities can be used to deploy and / or support the antenna according to the deployment methods described herein.

[0036] FIG. 7 illustrates an exemplary antenna structure 70 having the same conductive pattern as the antenna structure 60 of FIG. 6 . However, the shape of the support structure 76 is different to support the antenna conductive shape memory conductive components 72. As shown in FIG. 7 , at least some of the conductive components and / or shape memory composite components, or portions thereof, are off the surface of the support structure and only partially contact the support structure to support it. As shown, the support structure 76 defines a partial cone, or truncated cone. Radial conductive and / or shape memory composite components 72A are disposed along their entire surface of the support structure 76. However, radial longitudinal conductive components 72B extend within the support structure, away from the surface of the support structure 76. The conductive and / or shape memory composite components 72B are coupled at their terminal ends to the edges of the support structure 76.

[0037] FIG. 8 illustrates another exemplary antenna structure 80 having a support structure 86. The antenna structure 80 may be similar to the antenna structure of FIG. 3 having a similar conductive component 82 as component 32. The antenna structure 80 may also include a combination of a first component segment 82A extending along a surface of the support structure 86 and a second component segment 82B extending within the support structure 86. Those skilled in the art will recognize that other support structures 86 may also be used. For example, an annular support structure having a cross-sectional shape approximating the conductive component segment (i.e., the quadrilateral shown) may be used.

[0038] As shown in FIGS. 9-10 , the antenna may be defined by conductive traces formed on a support structure. The traces may be made of a conductive material. The traces may be made of a coating, fiber, wire, paint, or other structure supported on and / or in and / or through the support structure. The design of the antenna structures 90, 100 may be separated so that design considerations for the support are maximized while those for the antenna are also maximized. By decoupling the conductive material from the support structure, both design considerations may be improved. For example, fewer support structure components may be used, thus minimizing the package configuration while maintaining antenna response using an appropriate number of conductive components.

[0039] As shown in FIG. 9 , the antenna structure 90 can also include an additional support structure 99. The additional support structure can include a flexible material coupled to any combination of other additional support structures, support structures, shape memory composite components, and / or conductive components. The additional support structure can be used to support conductive components that may or may not be disposed on the support structure. In an exemplary embodiment, the additional support structure can be a string, an elongated flexible member, a wire, a band, or a combination thereof. The additional support structure can be used to reinforce one or more of the additional support structures, support structures, shape memory composite components, and / or conductive components. The additional support structure can be used to affect the shape, e.g., the deployed shape, of any combination of the additional support structures, support structures, shape memory composite components, and / or conductive components. For example, as can be seen in FIG. 9 , the additional support structure 99 can be used to reinforce the support structure 96 and also to create a reduced diameter cross-section by coupling the additional support structure 99 and / or support structure 96 to the interior of the antenna structure 90. Thus, additional support structures can be used to create complex shapes for use with novel antenna designs.

[0040] In an exemplary embodiment, any combination of the support structure, additional support structures, and / or other component parts of the system may comprise degradable materials.

[0041] In an exemplary embodiment, the shape memory composite material may be integrated with a support structure. The shape memory composite material may create a support structure.

[0042] In exemplary embodiments, the shape memory composite material can create a framework to which a support structure is attached. As described herein, the shape memory composite can reside within the support structure or can be bonded along the entire support structure. Also, the shape memory composite component can be bonded to the support structure along portions or points of the shape memory composite component. A combination of support structures and / or shape memory composite components can be used.

[0043] In exemplary embodiments, conductive materials may be combined with shape memory composite components. The conductive materials may be present within and / or on the surface of the shape memory composite, as described herein.

[0044] In exemplary embodiments, the conductive material may be supported by or on the support structure. The conductive material may be disposed on the support structure in any manner, such as on the surface of the support structure, within the support structure, and / or bonded to the support structure. In exemplary embodiments, the conductive material may be painted, coated, disposed on, woven into, or otherwise bonded to the support structure. For example, the conductive material may include thin copper sheet metal. The sheet metal may be patterned, disposed on, or bonded to the surface of the support structure. As another example, the conductive material may be a thin copper wire fiber. The fiber may be woven into or bonded to the support structure. The conductive material may be a metallic gossamer film or other conductive material. The conductive material may be a foil. The conductive material may be a coating. The conductive material may be a mesh foil. The conductive material may be a mesh.

[0045] In exemplary embodiments, additional structures may be used to deform and / or support the support structure and / or conductive components. In exemplary embodiments, the additional structures may include flexible components, which may also be shape-memory or non-shape-memory. The additional support structures may be coupled to the shape-memory components and / or support structures to bond the component parts together, define the deployed shape, support or create additional attachment points between the component parts, affect deployment, and otherwise contribute to the design of the antenna structure.

[0046] The exemplary embodiments described herein may use any combination of the features described herein. In exemplary embodiments, the antenna structure may include any combination of a support structure, a shape memory composite component, a conductive component, and additional structures, whether separate component parts and / or component parts integrated in one or more ways so that a single component part functions as two or more component parts. Exemplary embodiments include any combination of a support structure, a shape memory composite component, a conductive component, and additional structures with a flexible component. The flexible component comprises a component part that can bend at any point or along its length. In exemplary embodiments, any combination of a support structure, a shape memory composite component, a conductive component, and additional structures enables unstructured dynamic deformation. As described herein, unstructured dynamic deformation enables deflection that can be defined in a non-preconfigured or structurally limited manner by an external force that deforms the component.

[0047] 11A-12 illustrate exemplary embodiments of antenna systems 110, 120 including housings 111, 121A, 121B. The housings can be used to provide an external force to hold the antenna in a stowed configuration. Exemplary embodiments of the housings can be opened to remove the deformation force and allow the conductive components to unfold. The system can include an opening mechanism for opening the housing. The opening mechanism can include a hinge, a pyrotechnic door, an explosive bolt, a failure component, or any other system for restraining the antenna in its stowed state. In exemplary embodiments, the failure component is configured to withstand at least a threshold amount of applied force. The failure component is configured to intentionally fail when a force exceeding the threshold amount is applied. The failure component can be configured to apply a deformation force to restrain the shape memory component. The system can be configured to provide an additional force to deploy the antenna configured to overcome the threshold amount and cause the failure component to fail, releasing the antenna.

[0048] 11A-11C illustrate an exemplary deployment sequence according to embodiments described herein.

[0049] 11A, in which the antenna structure 112 is held in a stored position having a reduced storage volume through application of an external force; and, as seen in FIG. 11C, in which the antenna structure is fully deployed, having a larger volume when the external force is removed. In other words, the memorized or biased configuration may be a deployed configuration in which the antenna structure is configured for use as a deployable quadrifilar antenna configuration (as shown in FIG. 1) or other compact antenna configuration (as shown in FIGS. 2-13B or otherwise configured according to embodiments described herein). The antenna structure 112 may be disposed within the housing 111 in the stored configuration in an unstructured, deformed configuration.

[0050] As can be seen in FIG. 11B , the housing 111 may be opened or otherwise configured to remove the holding force on the antenna structure 112. In an exemplary embodiment, the housing may include a first part 111A and a second part 111B, where the first part and the second part may be separable. The first part 111A may be coupled to the second part 111B in the stowed configuration to provide a deformation force to hold the antenna structure in the stowed configuration. The first part 111A may be opened and / or separated from the second part 111B. When opened, the first part 111A may be held to the second part 111B, such as by a hinge or other connection. As shown in FIG. 12 , the first part 121A may be completely separated from the second part 121B. The first part and / or the second part may create a support substructure and / or a hub component for the antenna system.

[0051] 11C, once the deformation force is removed, the antenna structure 112 can fully deploy. Deployment may be through removal of a deformation force, such as that imparted to a shape memory composite component by a retention device. The retention device may be a housing or part of a housing and / or another component part described herein.

[0052] FIG. 12 illustrates an exemplary configuration according to embodiments described herein. FIG. 12 illustrates an exemplary antenna structure 120 including a shape memory composite component 122 and a support structure 126. The antenna structure 120 can include an outer housing configured to enclose the shape memory composite component and / or the support structure. The outer housing 123 can include portions that can be separated into a first portion 121A and a second portion 121B. The housings can be coupled together through a failure interface. For example, the failure can be through the application of a substance, an explosion, an ignition, or an additional force. The failure interface can be configured to hold the shape memory composite component in a stored, deformed configuration. The failure interface can be configured to fail under a desired condition. Upon failure, the shape memory composite material reverts to a memorized state, allowing the antenna structure to be deployed to a deployed configuration.

[0053] In exemplary embodiments, the support structure can define a gas-tight or semi-gas-tight cavity. During deployment, the support structure can be infused with a fluid to inflate it. The expansion of the support structure can be used to overcome the failure interface and release the antenna structure for deployment. The expansion of the support structure can assist the shape memory composite material in deploying to the memorized configuration. The expansion can be used to counter any creep or deformation that may occur in the antenna structure during extended periods of storage. The support structure can then release the expanding fluid over time. However, the shape memory composite material can then provide sufficient support to the antenna structure such that additional inflation fluid is not required to maintain the shape of the antenna structure during extended periods of deployment.

[0054] 13A-13C illustrate an exemplary deployment sequence according to embodiments described herein. Similar to the deployment shown in FIGS. 11A-11C, the antenna structure can include a shape memory composite component 132 that assumes a stowed configuration upon application of a deforming force. When the deforming force is removed and / or using a support structure defining an envelope that receives an inflation fluid, the antenna structure deploys and the shape memory composite component returns to its memorized configuration.

[0055] In an exemplary embodiment, the antenna structure is held within housings 131A, 131B, as seen in FIG. 13A. The housing can be a rigid structure to hold the antenna structure, including the shape memory composite component, and to apply a holding force to the antenna structure. FIG. 13A shows that the housing can include a first part 131A to partially enclose the antenna structure, with a second part 131B acting as a cover or lid for the first part 131A. The lid can be used to support the antenna structure or provide a holding force to the antenna structure for long-term storage.

[0056] Once ready for use and transport to space, second part 131B can be removed from first part 131A, as seen in FIG. 13B. First part 131A can thus define a first retention device for long-term storage. Long-term storage includes a time duration unknown herein, which may be a matter of minutes, hours, days, weeks, months, or years. In an exemplary embodiment, second retention device 131C provides a deformation force to continue to hold the antenna structure in a stowed configuration. Second retention device 131C can be used for short-term retention of the antenna structure. In an exemplary embodiment, short-term retention may be for a known, finite duration, even if the short-term retention is on the order of hours, weeks, months, or even years. As shown, second retention device 131C includes failure interface 133. The failure interface can be configured to tear, break, dissolve, or otherwise fail to allow the antenna structure to return to a memorized configuration. As shown, the second retention device 131C can define a thin covering sheet that includes a weakened portion that acts as the failure device 133. The weakened portion can include a portion of material that is perforated and therefore withstands less external force. Other configurations, such as thinner material cross-sections, perforations, tears, degradable materials, temperature-sensitive materials, and combinations thereof, may also be used and remain within the scope of the present disclosure.

[0057] FIG. 13C illustrates the deployment of the antenna structure as the shape memory material 132 overcomes the deformation force of the retention device 131C, such that the retention device 131C fails and the deformation force is removed. In an exemplary embodiment, the antenna structure includes a support structure 136 defining an expansion sleeve. The expansion sleeve may be inflated through the injection of one or more fluids, such as a gas, to apply additional force to the retention device 131C and overcome the failure interface 133. Thus, the injection of fluid into the expansion sleeve can release the antenna structure from the stored configuration and allow the shape memory composite component to return to the memorized configuration. The injection of fluid into the expansion sleeve can also assist the shape memory composite component in returning to the memorized configuration. The expansion sleeve can be inflatable or hold the expansion gas for a period of time to overcome or counteract potential creep that the antenna structure may experience from a longer duration in the shape memory composite component, or other shape retention of any component.

[0058] FIG. 14 illustrates an exemplary system according to embodiments described herein. As shown, an antenna system 140 can include one or more components within a housing 141. The housing 141 can be used for long-term storage. The housing can include a door 142. The door 142 can provide a deformation force to the antenna structure to hold the antenna in a stowed configuration. The housing and / or its door can be used to provide additional retention force in addition to the deformation force provided by the other component parts described herein. The additional retention force may be used for long-term storage and / or to provide additional environmental protection for the antenna assembly while stored in a terrestrial environment. Thus, the housing can be sealed between the housing 141 and the door 142. The door can be completely removed or simply opened using a hinge 143 or the like.

[0059] An exemplary embodiment of the system may include electronics for controlling portions of the system. For example, the sequencer 144 and / or electronics may include a communication system; an interface system for coupling to other electronic systems; a controller; a sequencer; and combinations thereof. The sequencer and / or electronics may communicate with the controller and / or enable operation of one or more of the system components described herein. For example, the controller may interface with a fluid injection system to inflate the inflation envelope described herein. For example, the controller may interface with a release mechanism for the antenna structure to remove the deforming force and allow the antenna to return to a memorized configuration. This may be by opening the housing door 142, by igniting an explosive to remove another faulty component, by inflating the inflation envelope with fluid to overcome a faulty interface, or a combination thereof.

[0060] An exemplary embodiment of the antenna system may include one or more actuators 145 for controlling one or more components of the system. As shown, an exemplary actuator may include a compressed gas canister and a controller. The compressed gas canister may be in fluid communication with the interior of the cavity of the inflation envelope created by the support structure described herein.

[0061] An exemplary embodiment of the antenna system can include an antenna structure 146. The antenna structure 146 can include one or more component parts including any combination of shape memory composite components, conductive components, support structures, housings, additional support structures, and the like.

[0062] Antenna designs according to embodiments described herein can transmit and receive circularly polarized waves, and it may be preferable for circularly polarized waves to travel through the ionosphere because the magnetic fields generated in the ionosphere by charged particles induce Faraday rotation in linearly polarized beams.

[0063] Antenna designs according to embodiments described herein may be omnidirectional to allow for any satellite orientation. Different antenna designs are provided and described herein merely by way of example. Some examples can provide both circular polarization and / or omnidirectionality. For example, an exemplary antenna design capable of providing both circular polarization and omnidirectionality can include a helical-shaped conductive component and / or define a biconical horn. Exemplary embodiments can use a polarizing feed. An exemplary helical design includes a quadrifilar (four helical conductor) helical antenna shown in FIG. 1. An exemplary biconical antenna design is shown in FIG. 2.

[0064] Exemplary embodiments described herein can include a shape memory component that can be dynamically deformed. Dynamic deformation, as used herein, includes unstructured deformation for storage and / or deployment. Exemplary embodiments of a shape memory component can bend, curve, or otherwise deform along the length of the shape memory component. Deformation can be along the entire length of the shape memory component or along a portion of the length. Dynamic deformation can fold into a smaller configuration, be stored in a SmallSat or other storage compartment, and be released to unfold into a deployed configuration. In exemplary embodiments, the shape memory component has a memorized configuration. During use, exemplary embodiments can include a stored configuration, in which the shape memory component can be retained through application of an external force in the deformed shape. Upon removal of the external force, such as a deforming force, the shape memory component unfolds into the memorized configuration. The memorized configuration can be a deployed configuration. Deployment can therefore be easy for shape memory component structures, since deployment simply requires removal of the mechanism that constrains the shape memory component (such as an antenna) in a folded or stored configuration.

[0065] In an exemplary embodiment, the shape memory component can include a shape memory composite. The shape memory composite can include fibers held in a matrix or resin. The shape memory component can be electrically conductive. To improve antenna gain, electrical conductivity can be increased by: (1) adding a metal powder to the matrix of the composite; (2) adding a thin metal foil wrapped around the shape memory composite component that creates the antenna; (3) adding a conductive paint applied to the surface of the shape memory component; and combinations thereof.

[0066] Exemplary shape memory composite materials include a substrate of one or more of carbon fiber, Vectran, Kevlar, fiberglass, fiberglass, plastic, or fiber metal. The substrate can include strands. The strands may be generally aligned along the length of the structure, may include one or more aligned configurations, may be wrapped or spirally arranged, may be woven, or any combination thereof. The shape memory composite material can include a substrate around and / or between the substrates. The substrate can be silicone, urethane, or epoxy. Exemplary shape memory composite materials are described in commonly owned patent application U.S. Patent Publication No. 2016 / 0288453, entitled "Composite Material." Exemplary embodiments include a high strain material to enable deformation. A high strain material typically has the ability to strain more than 3% without entering plastic deformation. In other words, the material can be indented more than 3%.

[0067] In exemplary embodiments, the shape memory composite material includes a fiber-to-resin volume fraction that can be controlled to achieve desired shape memory retention, even after extended storage in a folded / packaged state. An exemplary fiber-to-resin volume fraction is 52 to 65, i.e., 52 to 65 percent fiber or 48 to 35 percent matrix or resin. The average fiber-to-matrix ratio is about 58 percent. The fiber may be carbon, Kevlar, Vectran, nylon, etc., as described herein, and the resin may be urethane, silicone, epoxy, etc., as described herein as the matrix.

[0068] In an exemplary embodiment, a member constructed from a shape memory composite material may be electrically conductive to define the antenna shape. All portions of the component may be electrically conductive. The component may be made electrically conductive by incorporating an electrically conductive material into the shape memory material. The component material may include a metal powder, coating, wrapping, sheet, film, paint, strand, or combinations thereof. The electrically conductive material may be present in the fibers, resin, on the surface of the fibers, on the surface of the component material, or combinations thereof. In an exemplary embodiment, the shape memory composite component is electrically conductive to create the antenna shape by wrapping the component in a thin sheet of copper. The copper sheet may be glued or otherwise bonded to the exterior surface of the shape memory composite material shaft.

[0069] It should be emphasized that many variations and modifications may be made to the embodiments described herein, and that these elements are to be understood as particularly acceptable examples. All such modifications and variations are intended to be included within the scope of the present disclosure and protected by the following claims. Furthermore, the steps described herein may be performed all at the same time or in a different order than the steps listed herein. Furthermore, it will be apparent that the features and attributes of specific embodiments disclosed herein may be combined in different ways to form additional embodiments, all of which are within the scope of the present disclosure.

[0070] For reference purposes only, certain terminology may be used in the following description and is not intended to be limiting. For example, terms such as "upper" and "lower" refer to directions in the referenced drawings. Terms such as "front," "rear," "left," "right," "behind," and "side" describe the orientation and / or location of a component or portion of an element within a consistent, but arbitrary, frame of reference, as made clear by reference to the text and associated drawings describing the component or element under discussion. Additionally, terms such as "first," "second," "third," etc. may be used to describe individual components. Such terminology may include, among others, the above-mentioned words, derivatives thereof, and words of similar import.

[0071] As used herein, conditional language, such as, inter alia, "can," "could," "may," "for example," etc., is generally intended to convey that a particular embodiment includes a particular feature, element, and / or condition, unless specifically stated otherwise or as otherwise understood within the context in which it is used. However, such language also includes embodiments in which the feature, element, or condition is absent. Thus, such conditional language is generally not intended to imply that a feature, element, and / or condition is necessarily required for one or more embodiments, or that one or more embodiments necessarily exclude undescribed components from another embodiment.

[0072] Additionally, the following terminology may be used herein: The singular forms "a," "an," and "the" include plural referents unless the context clearly indicates otherwise. Thus, for example, a reference to an item includes a reference to one or more items. The term "ones" means one, two, or more and typically applies to the selection of some or all of a quantity. The term "plurality" means two or more of an item.

[0073] As used herein, the terms "about," "substantially," or "approximately" in connection with any numerical value, range, shape, distance, relative relationship, etc., indicate an appropriate dimensional tolerance within which a portion or collection of components can function for its intended purpose as described herein. Numerical ranges may also be provided herein. Unless otherwise indicated, each range is intended to include the endpoints and any quantity within the provided range. Thus, the range 2-4 includes 2, 3, and 4, as well as any subdivision between 2 and 4, such as 2.1, 2.01, and 2.001. Ranges also encompass any combination of ranges, such as 2-4 including 2-3 and 3-4.

[0074] As used in this specification and claims, the terms "comprises" and "comprising" and variations thereof mean that the specified features, steps or integers are inclusive. These terms are not to be interpreted to exclude the presence of other features, steps or components.

[0075] The features expressed in the foregoing description, or in the following claims, or disclosed in the accompanying drawings, in terms of their particular forms or means for performing a disclosed function or method or process for achieving a disclosed result, may, as appropriate, be used individually or in any combination to realize the invention in its diverse forms.

[0076] Although the embodiments of the present invention have been fully described with reference to the accompanying drawings, it should be noted that various changes and modifications will become apparent to those skilled in the art. It is understood that such changes and modifications are included within the scope of the embodiments of the present invention, as defined by the appended claims. Specifically, exemplary components are described herein. Any combination of these components may be used in any combination. For example, any component, feature, step, or part may be integrated, separated, subdivided, removed, duplicated, added, or used in any combination and remain within the scope of the present disclosure. The embodiments are merely exemplary and provide illustrative combinations of features, but are not limited thereto.

Claims

1. Conductive materials that create antenna configuration geometry a base structure for supporting the antenna; and a support structure to assist in deployment of the antenna, the support structure configured to decompose in the presence of atomic oxygen or solar radiation; An antenna comprising a stored configuration configured to fit within a reduced volume and a deployed configuration configured to fit within an increased volume, the increased volume being greater than the reduced volume.

2. An antenna as described in claim 1, wherein the support structure comprises a layer disposed on at least a portion of the conductive material, and the support structure is configured to decompose over a period of 1 to 5 days in the presence of atomic oxygen or solar radiation.

3. The antenna of claim 1 , wherein the base structure comprises a shape memory composite.

4. 4. The antenna of claim 3, wherein the antenna configuration geometry is an omnidirectional antenna for free space communications between a ground station and a spacecraft or between spacecraft.

5. 4. The antenna of claim 3, wherein the antenna configuration geometry is a quadrifilar helix antenna or a biconical antenna.

6. The antenna of claim 5 , wherein the support structure comprises a flexible membrane configured to create a dielectric membrane.

7. The antenna of claim 6 , wherein the support structure defines an envelope that creates an interior cavity, the envelope creating a gas semi-impermeable surface around the interior cavity.

8. The antenna of claim 7 further comprising an expansion system that supplies material to the interior cavity to expand the envelope.

9. The antenna of claim 8 , further comprising a vent configured to release material from the interior cavity after expansion of the envelope.

10. The antenna of claim 9 , wherein the conductive material is disposed on a surface of the base structure.

11. 11. The antenna of claim 10, wherein the base structure, the support structure, and the conductive material are each dynamically deformable to enable the antenna to be configured in a folded configuration and transitioned to an unfolded configuration.

12. The antenna of claim 11 , wherein the support structure is coupled to the base structure such that expansion of the envelope to deployment places the base structure in a desired configuration.

13. 13. The antenna of claim 12, wherein the support structure is configured to degrade in the presence of atomic oxygen or solar radiation over a period of 1 to 5 days.

14. The antenna of claim 12 further comprising a decomposable layer over at least a portion of the conductive material.

15. The antenna of claim 14 , further comprising a housing configured to apply a force to the base structure to maintain the base structure in the folded configuration.

16. storing the antenna in a stored configuration defining a reduced volume, the antenna comprising a shape memory material and an envelope; deploying the antenna to a deployed configuration defining an increased volume that is greater than the reduced volume; and Disintegrating the support structure defining at least a portion of the envelope after expansion of the envelope.

2. A method for deploying an antenna, comprising:

17. disposing the antenna within the housing to apply a retention force to the antenna to maintain the antenna in a retracted configuration; Opening the housing to remove the holding force on the antenna 17. The method of claim 16, further comprising:

18. The method of claim 17, wherein deployment of the antenna to the deployed configuration is through either the shape memory material returning to its memorized shape after removal of the retaining force, through expansion of the envelope, or a combination of the shape memory material and expansion of the envelope.

19. The method of claim 17, wherein deploying the antenna includes expanding the envelope and further includes allowing a support structure defining at least a portion of the envelope to degrade over a period of 1 to 5 days after expanding the envelope.

20. 20. The method of claim 19, wherein the antenna, after deployment, defines a quadrifilar helical antenna or a biconical horn.

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