High-efficiency front-end interface for the vibrating-string strain gauge sensors

Abstract

Sensor networks are becoming a reality in different applications. As matter to fact, in mobile equipments and battery-operated instrumentation, the design of low-power systems becomes critical, and the vibrating-string strain gauges generally doesn't work with low tensions of the commercial wi-fi or zegbee modules. In addition, the reduction of the power-supply voltage also degrades the power of the desired signal, while the noise power remains noticeable. So a special interface is necessary. In this work, we propose a highefficiency method based on the gating of the electromagnetic coil of the vibrating-string at the minimum energy to overcome the mechanical damping. Experimental waveforms for a low-cost interface implementation are also given to demonstrate its validity. © 2010 Springer Science+Business Media B.V.