A Pulsed-Biasing Strain Gauge Measurement System for Wireless Sensing Applications

This paper presents a pulsed-biasing strain gauge measurement system for wireless sensing applications. The use of pulsed-biasing on the strain gauge can reduce the power consumption of the sensor, which is crucial for low-power wireless sensors. Moreover, without using a constant bias current, power dissipated on the resistive bridge that includes the strain gauge can be reduced. Such reduction can also reduce measurement errors from an increased strain gauge temperature. A strain gauge wireless sensor was constructed using commercially available components. Measurement results show that the pulsed-biasing technique can be implemented with a duty cycle down to around 40% with negligible measurement error at a data rate of 32 Hz. The power saved is equivalent to an increased operation time of 50%.