Resistance-voltage transformation system for sensors in dynamic strain measurement and structural health monitoring

Abstract

A resistance-voltage (R-V) transformation system used in dynamic strain measurement for a structure is provided. The system has single-channel (SC) circuit units each for producing a voltage corresponding to a resistance of a sensing element of a structural-strain sensing network. Each SC circuit unit has a R-V transformation module for converting the resistance into the voltage, a band-pass filter module for filtering the R-V transformation module output after a direct-current bias therein is removed, and a high-gain amplification module for amplifying the filter output. The band-pass filter module is configured such that an unwanted low-frequency component induced by resistance drift of the sensing element is removed while allowing a guided-wave signal component to pass through. Particularly advantageous for the sensing network using nanocomposite sensing elements, the R-V transformation system is useful for a wide range of sensor resistance values, mitigating adverse effects of resistance drift, and enabling simplicity in wiring.