A two-dimensional bar code reader capable of seeing through paint may prove to be the foundation of a handheld three-dimensional ultrasound camera that it is hoped will vastly facilitate the non-destructive inspection of composite aerostructures.

Norwegian ultrasound specialist DolphiTech and EADS Innovation Works hope by the end of 2012 to have ready a prototype that they expect will be able to see through 8-10mm of composite material and provide images good enough to determine whether a structure has sustained damage not visible by normal surface inspection.

DolphiTech managing director Terje Melandso said the handheld camera should be fast and easy enough to use so that technicians in the field can take pictures of an area of an aircraft that has suffered an impact and either see immediately that there is no damage, or send a digital file to remote specialists who could make a fly-no fly judgment.

The camera would also be useful in manufacturing, to inspect for flaws in areas that are not normally accessible to larger scanners, he says.

The 2D barcode reader is valuable, he says, because if codes are embossed or engraved in a surface they can still be read if the surface has been painted or slightly damaged. The DolphiTech camera used a 16,000-element transducer to produce its 2D image in nine to 10 seconds, and a 3D version for aerospace or other industrial applications should be as easy to use as a video camera.

But, he says, while the scanner is in principle similar to the 3D ultrasound cameras now used in medical applications - for example to examine unborn babies - it is much less expensive.

The main thrust of the work with EADS Innovation Works will be to increase the area visible to the scanner, which currently sees a 3cm by 3cm (0.4 inch by 0.4 inch) patch. Melandso notes that this capability should be useful in the factory to inspect, say, the area around a drilled hole if there is any suspicion that it is not sound. However, such a small area limits the camera's usefulness to inspectors in the field, as they would have to know quite specifically where to look for damage, as it would be impracticable to scan large areas of, say, a fuselage.

EADS Innovation Works hopes the DolphiTech camera will complete its range of mobile non-destructive testing tools.

Source: Flight International