Wheatstone bridge approach to the inspection of composite materials

Abstract

Composite materials are used as main building blocks in aviation industry, due to better characteristics as compared with aluminium and alloys. Inspection methods for these materials must offer reliable information to enable a thorough assessment of the structural integrity of the aircraft. Non-destructive testing methods NDT are at the forefront of these techniques, where the associated sensors have to offer reliable data, based on flexible, non-contact and low cost equipament. The paper presents an eddy currents based NDT technique that enables the depiction of 1D and 2D flaws in carbon fibre reinforced polymer CFRP, where the associated electronic circuit block is based on a Wheatstone bridge for signal acquisition and processing purposes.