Foldable Solid RF Reflector Architectures
Aerospace
Foldable Solid RF Reflector Architectures (LAR-TOPS-383)
Enabling Deployable, Large-scale Reflectors in a Small Packaged Volume
Overview
Inventors at the NASA Langley Research Center have designed innovative foldable large-scale parabolic reflectors. This solution addresses the challenges of scaling solid surface reflectors to beyond
10-meter diameter, enabling higher gains, improved data transfer rates, and superior overall performance.
Leveraging an independently developed shape memory composite, two new foldable reflector architectures were designed that may be deployed through embedded compliant mechanisms. The concentric stack-and-connect architecture features a set of rigid reflective panels that packages concentrically while the umbrella architecture utilizes a thin shell reflective surface that stows like an umbrella.
These designs overcome the scaling complexities of other solid reflectors and prioritize lightweight materials and high packing efficiency. The precisely controlled deployment mechanisms ensure accurate shaping and alignment, making it an ideal solution for space communications and radio astronomy.
The Technology
NASA's foldable large-scale parabolic reflector technology introduces two innovative architectures:
Concentric Stack and Connect (shown on the right): This design uses a stack of lightweight rigid panels (e.g., hexagons) made of a carbon composite sandwich construction that are arranged concentrically, resulting in a compact stowed design. Each panel is deployed from the stack one at a time by activating pairs of tubular composite hinges, and a second mechanism closes the gap between the deployed panels to create a seamless reflective surface.
Umbrella (shown below): Employing a set of thin-shell composite gores suspended from stiff backbone ribs, this design allows the entire paraboloid to be folded and unfolded like an umbrella. A novel apparatus consisting of a set of mechanically actuated push and pull rods enables the controlled and synchronized stowage of the multiple flexible connected gores each forming a serpentine shape with one or more lobes. Structural deformable composite elements are incorporated around the perimeter and between the gores to increase the deployed stiffness of the overall reflector and enable the synchronized gore deployment.
Both architectures use shape memory composite elements that are initially folded during transportation. Upon reaching the destination, the shape memory composite is heated, triggering the shape memory effect and causing the actuators to extend slowly, unfolding the reflector to its desired shape. The lightweight deformable composite materials in the parabolic reflectors enable the compact stowage, reducing mass and volume needs during transport. Additionally, precise control over the deployment process ensures accurate shaping and alignment, enhancing overall system performance.
Benefits
- Lightweight: Implementing polymer composite panels and actuators significantly reduces the weight of the reflectors.
- Compact Packaging: The foldable reflectors may be packed in smaller volumes than other solid reflectors.
- Precise, Controllable Deployment: The shape memory composite actuators enable highly controlled deployment of the reflectors.
- Scalability: Enables construction of solid reflectors exceeding 10 meters in diameter.
- Enhanced Performance: Moving to solid reflectors at and above 10 meters can significantly improve gains and data transfer rates.
Applications
- Radio Astronomy/Communications: the 10-meter diameter reflectors will support S-band and above (> 2 GHz) RF data transmissions.
- Satellite Communications: High-gain reflectors for data transmission.
- Space Exploration: Deployable reflectors for lunar and planetary communication systems.
Technology Details
Aerospace
LAR-TOPS-383
LAR-20353-1
LAR-20513-1
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