Abstract
The use of planar-type sensors for the estimation of system properties has gained considerable importance in recent times because of its noncontact and nondestructive nature. The impedance of a coil in proximity of any conducting/nonconducting, magnetic/nonmagnetic surface is a complex function of many parameters, such as conductivity, permeability, and permittivity of near-surface materials, liftoff and coil pitch of the coil, etc. The transfer impedance (i.e., the ratio between the sensing voltage and the exciting current) of the planar-type microelectromagnetic sensors consisting of exciting and sensing coils is used for the estimation of the near-surface system properties. Two methods have been discussed for the postprocessing of output parameters from the measured impedance data. Based on the estimation of near-surface properties, it is possible to detect the existence of defects, to predict the degradation of material, fatigue, etc.
Original language | English |
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Pages (from-to) | 308-312 |
Number of pages | 5 |
Journal | IEEE Sensors Journal |
Volume | 4 |
Issue number | 3 |
DOIs | |
Publication status | Published - Jun 2004 |
Externally published | Yes |
Keywords
- Grid system
- Neural network model
- Nondestructive evaluation technique
- Planar-type sensors
- Property estimation