A Hybrid Electrical-Mechanical Wireless Magnetoelastic Sensor for Liquid Sample Measurements

摘要

This paper presents a hybrid passive wireless resonant electrical and mechanical sensor for enhanced sensitivity and specificity. Mechanical resonance measures the viscosity and electrical resonance measures the dielectric properties of liquid samples. The sensor is composed of two magnetoelastic (amorphous ferromagnetic ribbons) strips placed in parallel that are separated with a dielectric spacer forming a capacitor. An inductive coil is attached in parallel to this capacitor leading to an electrical resonant inductive-capacitive (L-C) tank. Both mechanical and electrical resonance frequencies are wirelessly measured using a single pickup coil hooked to an impedance analyzer. Several liquid samples, including food items, having different viscosity and dielectric properties are measured and key advantages of this sensor are demonstrated. This sensor can be used in food quality monitoring and can be integrated with passive RFIDs.