DailyIndia.com, FL
10-03-07
Boffins develop technology to quickly detect leaks in spacecraft
From our ANI Correspondent
Washington, Oct 3:Iowa State University researchers have developed a
technology that allows for quick detection of leaks in spacecraft.
Spacecraft risk getting their thin aluminium skin pierced by tiny meteors and
spacecraft debris flying through space. Even a tiny hole would mean a leak of
pressurized air.
But, leaks are hard to detect because spacecraft are full of life-support systems,
computers, controls, gear and research equipment, all of which can hide a leak.
This apart, astronauts also can't hear the telltale hiss of escaping air, which
blows outside the spacecraft and away from searching ears.
"NASA wants to be able to find these leaks. Fixing them is easy. But the question
is, 'Where is the leak? It is important that astronauts find that leak as quickly as
they can. A spacecraft can only produce so much oxygen. NASA can't afford for
it to slowly and steadily blow into the cold vacuum of space," said Dale
Chimenti, an Iowa State University professor of aerospace engineering.
As part of the tests, Prof. Chimenti and his team have now developed a sensor
that can find leaks by detecting the small vibrations in a spacecraft's skin caused
by escaping air.
The inch across square sensor includes an array of 64 elements that detect
vibrations as they radiate along the spacecraft. The different elements pick up
the vibrations at different times.
These differences can be analyzed by a computer to determine the direction of
the leak. Information added from multiple sensors helps find a leak in about a
minute, compared to the weeks required to find one with NASA's current
handheld, ultrasonic detection devices.
Prof. Chimenti said a major challenge was accounting for a reinforcing grid that
rises from the back of a spacecraft's shell and affects the travel of vibrations.
He said the scientists solved the puzzle by targeting the frequency range
measured by the sensors. They focussed on lower frequencies and that reduced
the effects of the reinforcing grid.