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

Demisable Reaction-Wheel Assembly

A document discusses the concept of a demisable motor-drive-and-flywheel assembly [reaction-wheel assembly (RWA)] used in controlling the attitude of a spacecraft. “Demisable” as used here does not have its traditional legal meaning; instead, it signifies susceptible to melting, vaporizing, and/or otherwise disintegrating during re-entry of the spacecraft into the atmosphere of the Earth so as not to pose a hazard to anyone or anything on the ground. Prior RWAs include parts made of metals (e.g., iron, steel, and titanium) that melt at high temperatures and include structures of generally closed character that shield some parts (e.g., magnets) against re-entry heating.

Posted in: Briefs, TSP, Mechanical Components

Read More >>

Spatial and Temporal Low-Dimensional Models for Fluid Flow

A document discusses work that obtains a low-dimensional model that captures both temporal and spatial flow by constructing spatial and temporal four-mode models for two classic flow problems. The models are based on the proper orthogonal decomposition at two reference Reynolds numbers. Model predictions are made at an intermediate Reynolds number and compared with direct numerical simulation results at the new Reynolds number.

Posted in: Briefs, TSP, Information Sciences

Read More >>

Garrett Reisman, Astronaut, NASA Johnson Space Center, Houston, TX

In March 2008, astronaut Garrett Reisman flew aboard the Space Shuttle Endeavour to the International Space Station, where he spent 95 days living and working in space. After performing his first spacewalk to help install the Space Station’s new robotic manipulator, called Dextre, he returned to Earth in June aboard the Space Shuttle Discovery.

Posted in: Podcasts

Read More >>

Electrocatalytic Reduction of Carbon Dioxide to Methane

A room-temperature electrocatalytic process has been investigated as a means of removing carbon dioxide from air and restoring oxygen to the air. The process was originally intended for use in a spacecraft life-support system, but may also have potential utility in applications on Earth in which the methane and oxygen produced might be utilized or vented to the atmosphere.

Posted in: Briefs, GDM, Briefs, Green Design & Manufacturing, Remediation Technologies

Read More >>

Oxide Fiber Cathode Materials for Rechargeable Lithium Cells

Fibers have been investigated at Johnson Space Center as alternatives to other powders used as lithium-intercalation compounds in cathodes of rechargeable lithium-ion electrochemical cells. The fibers can be pressed and sintered to form a cathode, without need for a binder or a conductive additive. The inter-grain contacts of the fibers are stronger and offer reduced loss of capacity from cycle to cycle.

Posted in: Briefs, GDM, Briefs, Batteries, Electronics & Computers

Read More >>

Electromagnetically Clean Solar Arrays

The term “electromagnetically clean solar array” (EMCSA) refers to a panel that contains a planar array of solar photovoltaic cells. The cells are laminated with shielding, narrow-current-loop wiring, and structural supports. EMCSAs could be useful in applications that require limited electromagnetic interference.

Posted in: Briefs, GDM, Briefs, Energy, Renewable Energy, Solar Power

Read More >>

System for Removing Pollutants From Incinerator Exhaust

A system for removing pollutants - primarily sulfur dioxide and mixed oxides of nitrogen - from incinerator exhaust has been demonstrated at Johnson Space Center. The system is also designed secondarily to remove particles, hydrocarbons, and CO, and is intended for use in an enclosed environment.

Posted in: Briefs, GDM, Briefs, Green Design & Manufacturing, Remediation Technologies

Read More >>

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