Electroactive Pressure Sensors for Smart Structures

A hardware-software interface for smart electroactive pressure sensors has been designed with the objective of providing a low power consumption and high performance impact monitoring system, integrated in new smart structures. The interface is specifically designed for its use with distributed pressure sensors based on conductive polymers. Their low cost and flexibility make them suitable for placing on large surfaces. The smart sensor integrates a microprocessor, a radio chip and a complete analog front end based on a period-modulated oscillator. The software developed implements new interface applications for this hardware in TinyOS. The response of the sensor, both loading and unloading, to different impact energies first, and then to different probe stiffness is presented. The behaviour of the sensor to impact is also compared to the response in static, and the different factors affecting the sensor response in both conditions are described. Comparing and contrasting the sensor signal with that of an impact pendulum shows that the sensor is suitable for measuring impact in both flexible and rigid structures.