Ikhana undergoes tiny sensor experience

Valley Press on ^ | Wednesday, August 6, 2008. | ALLISON GATLIN

[BenLurkin]

EDWARDS AFB - Engineers at NASA Dryden Flight Research Center are testing extremely small sensors - about the diameter of a human hair - to monitor changes in an airplane wing's shape during flight, hoping to harness the information to improve aircraft efficiency and safety by controlling the changes.

"We want to be able to change the shape of a wing," said Lance Richards, Dryden's Advanced Structures and Measurement group lead.

"The first step in changing the shape of a wing is knowing the shape."

The fiber-optic sensors, unlike traditional sensors and strain gauges, are extremely lightweight and are small enough not to disturb the flow of air over the wing.

With their small size, hundreds may be placed across the surface of the wing, each one equivalent to a bulky conventional sensor or strain gauge, Richards said.

The fiber optics also are immune to the problem of electromagnetic interference.

"They just have tremendous benefits," he said.

The sensor system has been undergoing flight testing affixed to the wings of Dryden's Ikhana unmanned aircraft.

Shallow strips of paint and filler material were removed from the wings' surface in order to embed the fiber optics on top of the structural surface.

Once painted over, the small sensors were hardly noticeable, Richards said.

The fiber-optic sensors eventually may be embedded in the composite structure of wings, integrated into the manufacturing process.

Traditional strain gauges are also in place on the wings to provide the data with which to validate the new technology.

The tests have been successful in proving the fiber-optic sensors' ability to accurately collect the necessary information, Richards said.