Wheel-Rail Force Measurement Based on Wireless LC Resonance Sensing

Abstract

Wheel-rail contact force measurement is one of the key issues in rolling stock monitoring. Traditional methods using strain gauges are a relative measurement, which require strong bonding on the wheel webs with complicated telemetry transmission systems. This paper proposes a wireless inductive-capacitive (LC) resonance sensing approach for non-contact measurement of wheel-rail contact forces. The proposed LC resonance sensor is low-cost, high sensitivity, and consists of a dual-layer rectangular inductance coil and a parallel capacitor. Validation using a standard dog-bone specimen tested on a universal testing machine was performed, with the resonant frequency of the proposed LC resonance sensor increasing monotonically with loading force. Investigation of lift-off and aspect ratio of the inductance coil shows that lower lift-off and lower aspect ratio offer better sensitivity. The proposed LC resonance sensing with LDC chip approach has great potential for rolling stock monitoring.