A remotely interrogatable passive microactuator using SAW correlation

In this paper, a novel remotely interrogatable ultrasonic microactuator is introduced utilising the complex signal processing functionality of an acoustic wave correlator. Fluid pumping can be achieved at ultrasonic frequencies by electrostatically actuating an edge clamped conducting diaphragm placed above the compressor IDT of the correlator. Secure interrogability of the wireless actuator is demonstrated by encoding the SAW correlator with a 5times2-bit Barker sequence and quantitatively deducing the code dependent diaphragm motion using finite element analysis. Moreover, the displacement optimization of the microactuator is addressed by the analyses of the device response for various acoustic mode excitations.