Special Coverage

Lightweight Internal Device to Measure Tension in Hollow- Braided Cordage
System, Apparatus, and Method for Pedal Control
Dust Tolerant Connectors
Foldable and Deployable Power Collection System
Iodine-Compatible Hall Effect Thruster
Development of a Novel Electrospinning System with Automated Positioning and Control Software
Home

Release of a Stuck Solar Array or Antenna

Several options are examined that may also be useful in remotely controlled terrestrial environments. Goddard Space Flight Center, Greenbelt, Maryland Satellite launches experience approximately one deployment failure every two years. These failures include a solar array or antenna that fails to deploy because it is stuck due to a mechanism failure, or is snagged by a cable or thermal blanket. Knowledge of the exact circumstances of the deployable failure is limited. Ground commanding of the spacecraft is conducted in an attempt to free the stuck deployable.

Posted in: Briefs, Mechanical Components, Machinery & Automation

Read More >>

High-Heat-Flux-Capable Boundary Layer Vortex Generator and Boundary Layer Transition Device

Lyndon B. Johnson Space Center, Houston, Texas Afixed geometry device has been developed to promote boundary layer transition and generation of streamwise vorticity, and is capable of withstanding entry heating environments for the Space Shuttle Orbiter. Designed to have a total height above the surface of the same order as the local boundary layer thickness, this device is approximately 0.25 in. (≈0.6 cm) tall and 4 in. (≈10 cm) long for the Orbiter entry application. Because temperature exposure is a key design factor for entry systems, the geometry has been optimized to establish peak heating rates and peak surface temperatures that are close to being spatially consistent on the protuberance. A relatively thin cross-section of 0.4 in. (≈1 cm) provides significant thermal radiation relief via conduction through the aft surface of the geometry. Sufficient mechanical strength to satisfy launch, ascent, entry, and landing conditions has been maintained in the design.

Posted in: Briefs, Mechanical Components, Machinery & Automation

Read More >>

Piezoelectric-Actuated Rotary Ultrasonic Motor

This motor can be used where rotary actuation is required, particularly in cryogenic and high-temperature applications. NASA’s Jet Propulsion Laboratory, Pasadena, California This actuator was developed out of a need for a cryogenic actuator that can operate effectively in spite of the thermal mismatch involved with construction materials that have different expansion coefficients. Also, there is a need for a cryogenic motor that can drive infrared systems and produce minimal thermal energy that can interfere with their operation.

Posted in: Briefs, Mechanical Components, Machinery & Automation

Read More >>

Method for Exfoliation of Hexagonal Boron Nitride

Langley Research Center, Hampton, Virginia NASA’s Langley Research Center has developed a method for exfoliating commercially available hexagonal Boron Nitride (hBN) into nanosheets a few atomic layers thick. Currently, hBN has limited use because it is insoluble with limited dispersibility, despite hBN having excellent thermal conductivity and electrical insulation. Langley’s novel method provides for exfoliated hBN nanosheets that are soluble or suspendable in a variety of solvents, allowing for their bulk preparation and incorporation into composites, coatings, and films.

Posted in: Briefs, Materials

Read More >>

Sucrose-Treated Carbon Nanotube and Graphene Yarns and Sheets

Applications include structural materials for aerospace vehicles, space habitats, and lightweight but mechanically robust consumer devices. Langley Research Center, Hampton, Virginia NASA’s Langley Research Center has developed a method to consolidate carbon nanotube yarns and woven sheets and graphene sheets via the dehydration of sucrose. The resulting materials are lightweight and high strength. Sucrose is relatively inexpensive and readily available; therefore the process is cost-effective.

Posted in: Briefs, Materials

Read More >>

Method for Manufacturing a Thin Film Structural System

Applications include Earth- and space-based inflatable structures, and chemical and radiation sensors. Langley Research Center, Hampton, Virginia NASA’s Langley Research Center has developed a technology that uses commercially available additive print manufacturing to add various levels of structural hierarchy to thin-film surfaces. The approach adds very little mass to thin films, but provides substantial performance enhancements, such as increased damage tolerance to tearing and ripping. NASA developed this technology to provide new and improved ways to produce robust, ultra-lightweight space structures such as solar sails, solar shades, and antennas. Beyond space applications, the technology is well suited for other thin-film applications.

Posted in: Briefs, Materials

Read More >>

Integrated Ceramic Matrix Composite-Carbon/Carbon Structures for Large Rocket Engine Nozzles and Nozzle Extensions

The material system could be used in rocket propulsion components in which temperature, environmental reactivity, and economy are increasingly demanding. Marshall Space Flight Center, Alabama Low-cost access to space demands durable, cost-effective, efficient, and low-weight propulsion systems. Key components include boost and upper stage rocket engine nozzles and extensions. Nozzle material options include ablatives, actively cooled alloys, and radiation-cooled composites and metals, each of which has known limitations. Metallic nozzles have high density and limited temperature capability. Carbon/carbon (C/C) is an attractive alternative, but has manufacturability, oxidation resistance, and joining ability concerns.

Posted in: Briefs, Materials

Read More >>

White Papers

From The Design Lab: An Insider’s Guide To Laser Sintering
Sponsored by Stratasys Direct Manufacturing
Force Transfer Machines
Sponsored by Morehouse
Beyond Telematics: IoT
Sponsored by Bsquare
Stencil-less Jet Printing for PCB Assembly
Sponsored by Imagineering
The Best Springs You Haven't Tried Yet
Sponsored by Rotor Clip
Electropolishing for Hydraulics and Pneumatics
Sponsored by Able Electropolishing

White Papers Sponsored By:

The U.S. Government does not endorse any commercial product, process, or activity identified on this web site.