Design and analysis of a differential waveguide structure to improve magnetostrictive linear position sensors

Implementation of High-Precision Magnetostrictive-Type Liquid Level Measurement System UsingWavelet Transform

Precise measurement of levels of liquids stored in tanks is essential for monitoring and predicting disasters by detecting leakages or arbitrary discharge of toxic materials. Therefore, tanks are typically equipped with a series of liquid level sensors. A magnetostrictive-type level sensor is composed of a waveguide, a current pulse interrogator, and a sensing coil for detecting reflective torsional signals caused by Wiedemann effect, which is themain principle of operation of magnetostrictive-type liquid level sensors. In order to implement a high-precision magnetostrictivetype liquid level measurement system, we used time–frequency analysis techniques such as wavelet transform (WT) to precisely detect the reflected signals. By using time–frequency analysis techniques such as short-time Fourier transform (STFT) and WT, a robust and precise liquid level measurement system can be implemented even in noisy environments.

Design of compensation coils for EMI suppression in magnetostrictive linear position sensors

This paper presents recent development on magnetostrictive linear position sensors (MLPS). A new compensation coil structure improves the EMI suppression and accuracy considerably. Furthermore, experimental results indicate that the new structure can improve the accuracy to ± 0.13 mm nearly double the ± 0.2 mm obtained with traditional structures. As another design continuation after the differential waveguide structure, this new structure is a practical and reliable implementation technique for the commercialization of MLPS.