'Edge of Light'showing up the cracks and defects in aircraft panels
"Edge of Light" showing up the cracks and defects in aircraft panels
Keywords: Panels, Aircraft, Non-destructive testing, Corrosion
A scanning device known as the "Edge of Light" that examines the surface topography of a material is helping identify cracks in ageing aircraft panels,before they become a critical problem. The scanner, developed by researchers at the National Research Council of Canada (NRCC), reflects light off the surface of the material and measures variations in light intensity in an area at the very edge of the light beam. The NRCC is currently working to develop licensing agreements to develop the non-destructive inspection (NDI) technology for a variety of uses including forensic studies and forgery detection.
The "Edge of Light" scanner beams a rectangular band of light at an angle onto the surface of the material to be examined. In the main zone of the band,the intensity of the light reflected into the detector remains constant. At the edge of the band, the intensity of light reflected fluctuates dramatically due to variations in the topography of the material that cause the angle of the beam to be deflected. The detector inside the scanner operates in the centre of this"Edge of Light" zone giving a high resolution map of surface topography.
Tests on the lap joints used in commercial airlines using "Edge of Light"technology have been able to pick up deformation between rivets caused by corrosion. Corrosive material builds up over the top of the original material,altering the surface topography of the material. This is deleted by the "Edge of Light" technique, giving it, it is claimed, the advantage over existing NDI technology.
Further details are available from Materials World, Institute of Materials. Tel: +44 (0) 171 451 7395; Fax: +44 (0) 171 839 4534; E-mail: Andrew-Mclaughlin@materials.org.uk
