Ultrasonic actuators for droplets displacement.

International audienc

Manipulations de gouttes sur une surface vibrante inclinée.

National audienc

Droplet ejector using Surface Acoustic Waves.

International audienc

Handling, detecting and positioning droplets using SAW.

International audienc

Remote vibration measurement: A wireless passive surface acoustic wave resonator fast probing strategy

International audienceSurface acoustic wave (SAW) resonators can advantageously operate as passive sensors which can be interrogated through a wireless link. Amongst the practical applications of such devices, structural health monitoring through stress measurement and more generally vibration characteristics of mechanical structures benefit from the ability to bury such sensors within the considered structure (wireless and battery-less). However, measurement bandwidth becomes a significant challenge when measuring wideband vibration characteristics of mechanical structures. A fast SAW resonator measurement scheme is demonstrated here. The measurement bandwidth is limited by the physical settling time of the resonator (Q/π periods), requiring only two probe pulses through a monostatic RADAR-like electronic setup to identify the sensor resonance frequency and hence stress on a resonator acting as a strain gauge. A measurement update rate of 4800 Hz using a high quality factor SAW resonator operating in the 434 MHz Industrial, Scientific and Medical band is experimentally demonstrated

A Pressure Sensor Based on a HBAR Micromachined Structure

International audienceIn this work, we propose a pressure sensor fabricated on compound LiNbO3/Silicon/Silicon substrates obtained by Au/Au bonding at room temperature and double face lapping/polishing of LiNbO3/silicon stack and a final gold bonding with a structured silicon wafer. Sensitivity of the final sensor to bending moments then is tested and results show pressure sensitivity of such devices