NRL brings inertia of space to robotics research

Jul 18, 2012
Precision honed to within +/-0.0018 inches tolerance across its surface, the Gravity Offset Table (shown right) will allow scientists to emulate the inertia of space in the laboratory using full-size spacecraft and robotic arms like the Front-End Robotic Enabling Near-Term Demonstration (FREND) arm pictured center. Credit: US Naval Research Laboratory

The U.S. Naval Research Laboratory Spacecraft Engineering Department's space robotics research facility recently took possession of a one-of-a-kind 75,000 pound Gravity Offset Table (GOT) made from a single slab of solid granite.

To emulate the of found in space on full-scale replica spacecraft on requires not only a hefty amount of air to 'float' the object, but a precision, frictionless, large surface area that will allow researchers to replicate the effects of inertia on man-made objects in space.

"We accomplish this by floating models of spacecraft and other resident space objects on air bearings –similar to the dynamics of an upside-down air hockey table," said Dr. Gregory P. Scott, space robotics scientist. "Based on the inertia of the 'floating' system, a realistic spacecraft response can be measured when testing thrusters, attitude control algorithms, and responses to contact with other objects."

Currently, the grappling, or capture, of spacecraft in orbit is accomplished by specifically engineered pre-configured couplers and mating mechanisms. To capture and service a 'free-flying' orbiting spacecraft that has no conventional coupling mechanism, researchers must first be able to demonstrate minimal rates of error in a cost effective and efficient manner using many spacecraft configurations here on Earth.

Honed by Precision Granite® to federal 'AAA' specifications, the 20 feet by 15 feet, 1.5-foot thick single piece of granite is within +/- 0.0018 inches flat across its surface. The precision GOT will allow NRL researchers to precisely simulate the frictionless motion of objects in space and understand the dynamics of docking and servicing satellites on-orbit — a function of increasing importance as rising launch costs and the addition of new orbiting spacecraft can be offset by the repair or updating of assets already in Earth orbit.

Quarried from the Raymond Granite Quarry, Clovis, Calif., the 450 cubic-foot, 37.5 ton GOT slab is thought to be the largest, single slab, precision granite table in the world with tolerances capable of allowing engineers to simulate service of full-scale satellite with significant structural flexibility to a degree of accuracy unmatched by any other space robotics facility.

Explore further: Total lunar eclipse before dawn on April 4th

Related Stories

Venus Express spacecraft fires main engine

Feb 20, 2006

One hundred days after its launch to Venus, the European Space Agency's Venus Express has successfully tested its main engine for the first time in space.

U.S.-French satellite prepared for launch

May 01, 2008

A U.S.-French spacecraft designed to continue a long-term survey of Earth's oceans has arrived in the United States for its final launch preparations.

Recommended for you

Total lunar eclipse before dawn on April 4th

16 hours ago

An unusually brief total eclipse of the Moon will be visible before dawn this Saturday, April 4th, from western North America. The eclipse happens on Saturday evening for Australia and East Asia.

Cassini: Return to Rhea

Mar 30, 2015

After a couple of years in high-inclination orbits that limited its ability to encounter Saturn's moons, NASA's Cassini spacecraft returned to Saturn's equatorial plane in March 2015.

Comet dust—planet Mercury's 'invisible paint'

Mar 30, 2015

A team of scientists has a new explanation for the planet Mercury's dark, barely reflective surface. In a paper published in Nature Geoscience, the researchers suggest that a steady dusting of carbon from p ...

It's 'full spin ahead' for NASA soil moisture mapper

Mar 30, 2015

The 20-foot (6-meter) "golden lasso" reflector antenna atop NASA's new Soil Moisture Active Passive (SMAP) observatory is now ready to wrangle up high-resolution global soil moisture data, following the successful ...

What drives the solar cycle?

Mar 30, 2015

You can be thankful that we bask in the glow of a relatively placid star. Currently about halfway along its 10 billion year career on the Main Sequence, our sun fuses hydrogen into helium in a battle against ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.