This invention relates to protective shields for space vehicles in general, and in particular, to telescopically retractable domes for providing thermal and micrometeoroid and orbital debris (“MMOD”) protection for docking mechanisms, hatches, and other equipment disposed on an exterior surface of a space vehicle, space station, space exploration habitat, and the like.
The environment of space is harsh and can subject the equipment used on the exterior of space vehicles, space stations, and space exploration habitats, such as hatches, docking mechanisms, antennae, cameras, sensors and the like, to a wide variety of potentially harmful agents, including strong thermal radiation and micrometeoroid impacts. Consequently, it is frequently desirable to provide a protective shield over the affected equipment to ameliorate the damaging effects of such elements. Conventional space vehicle protective doors and shields are typically generally planar in shape and cantilevered to one side of the area of the affected equipment when disposed in an open position, and can therefore interfere with the openings that they close, or the equipment on the surface of the vehicle that they are intended to protect, such as a docking ring or an antenna.
Consequently, a long-felt but as yet unsatisfied need exists for a simple, reliable protective shield, or cover, that can be deployed over a docking mechanism, hatch, or other equipment used on the surface of a space vehicle to provide at least thermal and MMOD protection for the equipment, and that overcomes the disadvantages of conventional doors and shields as discussed above.
In accordance an exemplary embodiment of the present invention, a simple, reliable, telescopically retractable dome is provided that can be deployed over a docking mechanism, hatch, or other equipment disposed on the surface of a space vehicle to provide at least thermal and MMOD protection for the equipment, and that is capable of being retracted substantially out of the way of the protected equipment when not in use, to avoid interference with access to and use of the equipment.
In an exemplary embodiment thereof, the protective dome comprises a plurality of rigid, arcuate segments subtended by a common angle, each having respective opposite ends respectively pinioned at opposite sides of the feature to be protected at about the surface of the vehicle for independent rotational movement of the segment about an axis extending through the opposite ends thereof, and through an arcuate path of revolution extending over the protected feature. Each of the rigid segments has a respective radial size that is arranged such that, in a deployed position of the dome, in which adjacent segments are rotated apart from each other at a maximum relative angle therebetween, the segments overlap at their respective edges, and combine with each other to form an arcuate shield over the protected feature that extends down to the surface of the vehicle. In a retracted position of the dome, in which adjacent segments are rotated together at a common angle relative to the surface of the vehicle, the segments are nested in a radial alignment with each other. Advantageously, the segments may comprise at least one of a thermal protection material and a micrometeoroid- and debris-resistant material, and a thermal seal may be disposed between adjacent segments to thermally insulate the feature more completely from ambient space when the dome is deployed over it.
In one exemplary embodiment, the arcuate segments each comprises a segment of a sphere, such that, in the deployed position, the dome is generally hemispherical in shape. In other embodiments, the segments may be polygonal in shape. In a “bi-fold” embodiment, the arcuate segments may comprise two groups, each defining a portion of the arcuate shield formed over the feature, which mate with each other at, e.g., a vertical plane extending through the feature when the dome is deployed. In this embodiment, an even number of segments is provided, half of which are grouped on one side of the protected feature, and the other half of which are grouped on an opposite side thereof.
In another advantageous embodiment, the protective dome may include a protective annular bezel having an internal diameter that is larger than the diameter of any of the segments, which is disposed on the surface of the vehicle and aligned generally concentrically with the feature, and the segments can be arranged to reside below an upper periphery of the bezel when the protective dome is in the fully retracted position.
A better understanding of the above and many other features and advantages of the present invention may be obtained from a consideration of the detailed description thereof below, particularly if such consideration is made in conjunction with the appended drawings, wherein like reference numerals are used to identify like elements illustrated in one or more of the figures.
A first exemplary embodiment of a rigid, telescopically retractable protective dome 10 for protecting a feature 1 on an exterior surface 2 of a space vehicle 3 in accordance with the present invention is illustrated in
In the particular telescoping dome 10 embodiments illustrated in the figures, each of the arcuate segments 12 comprises a segment of one of a plurality of radially nested spheres that are subtended by a common angle θ (see
The generally arcuate segments 12 of the rigid, telescoping dome 10 illustrated have respective radii 16 that are staggered in size such that, in a fully deployed position of the dome, as illustrated in
An alternative, “bi-fold” embodiment of a telescoping rigid protective dome 10 is illustrated in
The various embodiments of the telescoping, rigid protective domes 10 of the present invention may further advantageously comprise an annular protective bezel 20 having an internal diameter larger than the diameter of any of the spherical segments of the dome, which is disposed on the surface 2 of the vehicle 3 and aligned generally concentrically with the feature 1 protected by the dome, as illustrated in
A partial cross-sectional view of two adjacent arcuate segments 12 of an exemplary embodiment of a rigid protective dome 10 in accordance with the present invention is illustrated in
Perspective views of the protective dome 10 of
The rigid arcuate segments 12 of the telescoping protective domes 10 may be fabricated of a wide variety of materials, e.g., a metal or a composite, such as an epoxy resin, which may optionally be reinforced with a glass, metal or carbon-fiber mesh. Advantageously, the cover may be coated with or made to incorporate at least one of a thermal protection material and a micrometeoroid and orbital debris (“MMOD”) resistant barrier for shielding purposes.
By now, those of skill in this art will appreciate that many modifications, substitutions and variations can be made in and to the materials, apparatus, configurations and methods of implementation of the present invention without departing from its spirit and scope. Accordingly, the scope of the present invention should not be limited to the particular embodiments illustrated and described herein, as they are merely exemplary in nature, but rather, should be fully commensurate with that of the claims appended hereafter and their functional equivalents.
This application is related to U.S. application Ser. No. ______ [Attorney Docket No. M-15516 US], filed herewith, which is incorporated herein by reference in its entirety.
The invention described herein was made in the performance of work under NASA Contract No. NAS8-01099 and is subject to the provisions of Section 305 of the National Aeronautics and Space Act of 1958 (72 Stat.435: 42 U.S.C. 2457).