Smallsat attitude control and energy storage

mechanical and fluid systems
Smallsat attitude control and energy storage (GSC-TOPS-140)
Reaction spheres for multi-axis attitude control and energy storage on small satellites
Overview
This NASA technology reduces the overall size and net power consumption of conventional three-axis attitude control systems by replacing reaction wheel ensembles with reaction spheres.

The Technology
Reaction spheres technology operate on a physics similar to reaction wheels, which by the conservation of angular momentum uses a rotating flywheel to spin a body in the opposite direction. Sphere systems that utilize magnetic torqueing rather than mechanical are also smaller, are more reliable, have low friction losses, and have improved lifetime performance. The proposed reaction sphere provides improved performance over traditional wheels and satisfies the push for component miniaturization, increased pointing accuracy, and power efficiency on CubeSats. Primary aims are to develop a low-friction method to contain a sphere in spaceflight and determine the feasibility of on-orbit momentum storage to supplement battery power. With appropriate placement of permanent magnets, the sphere systems can generate relatively equal value of momentum and torques for any spin axis. This sphere at any speed, produces more momentum than the wheels, resulting in faster attitude stability.
Sochi, Russia 2014
Benefits
  • Infinite rotation degrees of freedom
  • Smaller, more reliable, low friction losses

Applications
  • Transportation
  • Generator manufacturing
Technology Details

mechanical and fluid systems
GSC-TOPS-140
GSC-17252-1
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Image of the SpaceSuit Roboglove Prototype
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Pilots in cockpit of a plane.
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