Deployable Antenna Reflectors Array Formed of Multiple Connected Gores
20240313415 ยท 2024-09-19
Inventors
- Juan M. Fernandez (Norfolk, VA, US)
- Andrew F. Paddock (Newport News, VA, US)
- Kevin DeMarco (Yorktown, VA, US)
Cpc classification
International classification
Abstract
Antenna reflectors having a diameter of 10 or more meters include dimensionally and thermally stable deformable composite reflective material that enables efficient packaging of solid surface segmented reflectors and a folding scheme and architecture that enables self-deployment to support S-band and above RF (?2 GHz) transmissions.
Claims
1. An antenna reflector array having at least a deployed position and a stowed position, the array comprising: a thin-shell elastic surface including multiple flexible radial gores discretely connected circumferentially to form a surface of revolution reflective surface on a first side thereof in the deployed position, wherein each of the multiple flexible gores is connected to two other of the multiple flexible gores at edges thereof by two or more thin-shell gore-to-gore connectors, further wherein the gore-to-gore connectors are located on a non-reflective side of each flexible gore; a backbone structure comprising multiple rigid arms for supporting the multiple connected, flexible gores, wherein each of the multiple flexible gores is attached to one of the multiple rigid arms on a non-reflective side thereof by discrete flexible connectors; and a deployment mechanism for changing the array between the deployed and stowed positions, the deployment mechanism including multiple rigid arms and a central circular hub, each of the multiple rigid arms including a hinge at one end thereof, the hinge being further connected to the central circular hub; wherein in the stowed position, each of the multiple flexible gores assumes a serpentine shape having at least one or more lobes.
2. The antenna reflector array of claim 1, where each of the multiple flexible gores includes doubly curved circumferential stiffeners as an inner skirt portion and an outer skirt portion formed of a thin composite material with a longitudinal curvature matching an inner and outer perimeter of the surface of revolution in a deployed position and a transverse curvature providing out-of-plane stiffness.
3. The antenna reflector array of claim 2, wherein the thin composite material is a shape memory composite (SMC) substrate and further wherein a shape of the inner skirt portion and outer skirt portion is controllable by an external stimulus between a first shape and a second shape, wherein the external stimulus is selected from the group consisting of mechanical load, heat, electrical field or magnetic field.
4. The antenna reflector array of claim 3, wherein the external stimulus is heat and further wherein each of the inner skirt portion and outer skirt portion include at least one controllable heater.
5. The antenna reflector array of claim 1, wherein each of the two or more gore-to-gore tabs is formed of a thin composite material and further wherein each of the one or more gore-to-gore connectors is controllable by an external stimulus between a first shape and a second shape, wherein the external stimulus is selected from the group consisting of mechanical load, heat, electrical field or magnetic field.
6. The antenna reflector array of claim 5, wherein a first shape of each of the one or more gore-to-gore connectors is selected from the group consisting of: a doubly curved shape wherein a longitudinal curvature matches a perimeter of the surface of revolution at its radial location in a deployed position and a transverse curvature providing out-of-plane stiffness; a single curved shape having either longitudinal or transverse curvature; and a flat shape.
7. The antenna reflector array of claim 5, wherein the thin composite material is a shape memory composite (SMC) substrate and each of the one or more gore-to-gore connectors includes at least one controllable heater to apply heat as the external stimulus.
8. The antenna reflector array of claim 1, wherein the multiple rigid arm hinges connected to the central hub are conFIG.d to be mechanically actuated synchronously.
9. The antenna reflector array of claim 1, wherein multiple rigid arm hinges connected to the central hub are passive and the deployed position is achieved by stored strain energy in the serpentine shape from the stowed position.
10. The antenna reflector array of claim 1, wherein at least one circular band or loop constrains the outer diameter of the reflector array in the stowed position, and further wherein the at least one circular band or loop controls a rate of deployment of the reflector array to the deployed position, wherein for two or more circular bands or loops, the rate of deployment is controlled by progressively increasing the diameter of two or more circular bands or loops.
11. The antenna reflector array of claim 2, wherein the inner skirt portion, the outer skirt portion and the gore-to-gore connectors assist in achieving the deployed position of the reflector array when actuated between a first shape and a second shape.
12. The antenna reflector array of claim 1, wherein each of the multiple flexible gores is comprised of an elastic thin-ply carbon fiber reinforced polymer (CFRP) laminate.
13. An antenna reflector array having at least a deployed position and a stowed position, the array comprising: a thin-shell elastic surface including multiple flexible radial gores discretely connected circumferentially to form a surface of revolution reflective surface on a first side thereof in the deployed position, wherein the surface is formed of two separate concentric gore rings comprised of multiple flexible connected gores and further wherein a first gore ring has a first inner circumference and a first outer circumference and a second gore ring has a second inner circumference and second outer circumference and further wherein the first inner circumference is the smallest circumference of the surface of revolution reflective surface and the second outer circumference is the largest circumference of the surface of revolution reflective surface; a deployment mechanism for changing the array between the deployed and stowed positions, the deployment mechanism including multiple first rigid arms, multiple second rigid arms and a central circular hub; and a backbone structure for supporting the multiple connected, flexible gores in each gore ring, wherein each of the multiple flexible gores in the first gore ring is attached to one of the multiple first rigid arms on a non-reflective side thereof by discrete flexible connectors, each of the multiple first rigid arms including a first hinge at a first end thereof, the first hinge being further connected to the central circular hub and a second hinge at a second end thereof, and further wherein each of the multiple flexible gores in the second gore ring is attached to one of the multiple second rigid arms on a non-reflective side thereof by discrete flexible connectors, each of the multiple second rigid arms being further connected to the second hinge of one of the multiple first rigid arms of a flexible gore in the first gore ring; wherein in the stowed position, each of the multiple flexible gores assumes a serpentine shape having at least one or more lobes.
14. The antenna reflector array of claim 13, where each of the multiple flexible gores includes a doubly-curved circumferential stiffener as an inner skirt portion and an outer skirt portion with a longitudinal curvature matching the inner and outer perimeters of the concentric ring surface of revolution in the deployed position and a transverse curvature providing out-of-plane stiffness, wherein the inner skirt portion and outer skirt portions are formed of a thin composite material and further wherein a shape of each of the inner skirt portion and outer skirt portions is controlled by an external stimulus between a first shape and a second shape, wherein the external stimulus is selected from the group consisting of mechanical load, heat, electrical field or magnetic field.
15. The antenna reflector array of claim 14, wherein the external stimulus is heat and further wherein each of the inner skirt portion and outer skirt portion include at least one controllable heater.
16. The antenna reflector array of claim 13, where each of the multiple flexible gores in the first gore ring is connected to two other of the multiple flexible gores in the first gore ring at edges thereof by two or more gore-to-gore connectors located on a non-reflective side of each flexible gore; and each of the multiple flexible gores in the second gore ring is connected to two other of the multiple flexible gores in the second gore ring at edges thereof by two or more gore-to-gore connectors located on a non-reflective side of each flexible gore.
17. The antenna reflector array of claim 13, wherein each of the two or more gore-to-gore connectors is formed of a thin composite material and further wherein each of the one or more gore-to-gore connectors is controllable by an external stimulus between a first shape and a second shape, wherein the external stimulus is selected from the group consisting of mechanical load, heat, electrical field or magnetic field, the first shape of each of the one or more gore-to-gore connectors is selected from the group consisting of: a doubly curved shape wherein a longitudinal curvature matches a perimeter of the surface of revolution at its radial location in a deployed position and a transverse curvature providing out-of-plane stiffness; a single curved shape having either longitudinal or transverse curvature; and a flat shape.
18. The antenna reflector array of claim 17, wherein the thin composite material is a shape memory composite (SMC) substrate and each of the one or more gore-to-gore connectors includes at least one controllable heater to apply heat as the external stimulus.
19. A system for stowing a deployed antenna reflector array comprising: a first circular central hub having multiple first pushrods connected thereto and second circular central hub having multiple second pushrods connected thereto, wherein each of the multiple first pushrods is mechanically connected to one of the multiple second pushrods; further wherein, the first circular central hub, the multiple first push rods and the multiple second push rods are located on a reflective side of a surface of revolution reflective surface of an array of multiple connected flexible radial gores and the second circular hub is located on an opposite side of the surface of the array; and the second circular central hub further being connected to multiple third pushrods at first ends thereof, wherein each of the multiple third pushrods is connected to the multiple second pushrods by links at second ends thereof; the first, second and third pushrods and links being capable of folding the deployed antenna array for stowing into a substantially cylindrical configuration with the multiple flexible connected gores each forming a serpentine shape with one or more lobes.
20. The system of claim 19, wherein the surface of revolution reflective surface is formed of two separate concentric gore rings comprised of multiple flexible connected gores and further wherein a first gore ring has a first inner circumference and a first outer circumference and a second gore ring has a second inner circumference and second outer circumference and further wherein the first inner circumference is the smallest circumference of the surface of revolution reflective surface and the second outer diameter is the largest diameter of the surface of revolution reflective surface.
Description
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0012] Example embodiments will become more fully understood from the detailed description given herein below and the accompanying drawings, wherein like elements are represented by like reference characters, which are given by way of illustration only and thus are not limitative of the example embodiments herein.
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DETAILED DESCRIPTION
[0028] It is to be understood that the invention may assume various alternative orientations and step sequences, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification, are simply exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise.
[0029] An exemplary drawing representation of a first antenna reflector array 100 in its fully deployed state is shown in
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[0032] In a first embodiment of the second antenna reflector array 100, the backbone support structure includes 6 single rigid arms 120, one for each gore as shown in
[0033] As shown in more detail in
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[0039] An exemplary drawing representation of antenna reflector array 100 in its fully deployed state with connected Ground Support Equipment (GSE) is shown in
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[0043] The deployment process of the reflector can occur via the following methods or combination thereof: 1) by the radial arm hinge connectors 125 affixed to the central hub being mechanically actuated synchronously, by for example a deployment motor; 2) by the radial arm hinge connectors 125 affixed to the central hub being passively rotated by moments created about their hinge joints 127 by the multiple connected gore surface folded in a serpentine pattern, releasing the strain energy stored in the elastic thin-shell material during the stowed process; 3) by at least one or more circular bands or loops constraining the outer diameter of the stowed reflector being panned out by a reeling mechanism that controls the rate of reflector deployment by progressively increasing the diameter of the bands or loops; 4) by the SMC substrate components post-bonded to the elastic reflective surface (skirts and gore-to-gore connectors) actuating between a second programmed shape and a first original shape.
[0044] Additional details supporting features of one or more embodiments herein may be found in the conference manuscript to Juan M. Fernandez et al., SEGMENTED, PLEAT-FOLDED AND RIB-SUPPORTED THIN-SHELL COMPOSITE ANTENNA REFLECTOR, 41.sup.st ESA Antenna Workshop on Large Deployable Antennas, 25-28 Sep. 2023 at ESA-ESTEC in Noordwijk, The Netherlands, the contents of which is incorporated herein by reference in its entirety.
[0045] All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.
[0046] The use of the terms a and an and the and similar referents in the context of describing the embodiments (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms comprising, having, including, and containing are to be construed as open-ended terms (i.e., meaning including, but not limited to,) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., such as) provided herein, is intended merely to better illuminate the features of the embodiments and does not pose a limitation on the scope of the embodiments unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the embodiments.
[0047] Preferred embodiments are described herein. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, these embodiments includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the embodiments unless otherwise indicated herein or otherwise clearly contradicted by context.