Tilt Angle Measurement Based on Arrayed Eddy Current Sensors

Abstract

Eddy current (EC) sensor works based on the electromagnetic induction principle and has been widely applied in the industrial testing and evaluation due to its robustness and environmental adaptability. Meanwhile, tilt angle measurement is mainly based on the laser or visual method, which is strict with the measurement environment and not suitable for the industrial applications. In this paper, a novel tilt angle measurement method based on arrayed EC sensors is proposed. Both the simulation and experiments indicate that the measured error is approximately linear with tilt angle and the accuracy after compensation is 0.25 o . In conclusion, this research cannot only broaden the scope of EC application, but also overcome the shortcomings of existing angle measurement methods.

Eddy Current Measurement for Planar Structures

“…The probe tilt is identified as one of the major sources of noise in EC surface inspections [44]. The FEM and BEM methods can model the tilted probes naturally [45], while, for the analytical model, the geometry is no longer axisymmetric and special treatments are required to represent the electromagnetic field [15]. The tilt effect has been studied for decades employing the methods including the SOVP [46], and the electromagnetic field of arbitrary current source above a conductive half-space [47].…”

Analytical model of tilted driver–pickup coils for eddy current nondestructive evaluation

“…[3,4] Driver-pickup probes have an advantage over one-coil probes in that they have higher gain, wider frequency range, and immunity to thermal drift, because the driver and pickup coil can be individually designed for a specific application. [5] However, a probe sometimes tilts due to surface deformation [3] or poor surface treatment. [6] Basically, eddy current signals are fairly sensitive to probe inclination.…”