Conference Paper

Portable eddy current NDT instrument using two different implementations.

DOI: 10.1109/EUROCON.2011.5929409 Conference: Proceedings of EUROCON 2011, International Conference on Computer as a Tool, 27-29 April 2011, Lisbon, Portugal
Source: DBLP

ABSTRACT This paper describes two implementations towards the development of a portable low-cost system capable of detecting defects on metallic surfaces through non-destructive testing. The defect detection is made via an eddy-current probe using a giant magnetoresistor (GMR) sensor. Both approaches use a computer mouse as a position device to locate the probe and deliver a graphical representation to facilitate the defect analysis. One implementation is based on a planar excitation coil, embedded power supplies and the signal processing is made by a dsPIC. The dsPIC controls the signal generation, the measurement procedure and the communication. The defect visualisation can be made in a LCD in real-time or transmitted to a PC. The other implementation uses a low-cost analog system to reduce the data processing required to detect the surface defects. The controller is a PIC microcontroller that does all the analog/digital conversions and transmits the defect data to a PC via wireless channel.

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