Soft dielectric elastomer actuator micropump

Abstract

This paper presents a miniaturized soft dielectric elastomer actuator (DEA) micropump which was demonstrated in microfluidic application. A strain-induced pre-stretched DEA undergoes expansion when subjected to high voltage, providing a two-way actuation in the presence of a pull-up spring. The DEA has been integrated with a microfluidic device with a diffuser element that enables it to pump the liquid in a controlled manner. At 4.2 kV applied voltage, a maximum deflection of 0.42 mm has been recorded, whereby a higher voltage causes the DEA layer to show severe wrinkle formation before it ruptures and fails. The dynamic response deflection of each repetitive actuation cycle has achieved high reliability at the low operating frequencies of 0.1 Hz and 0.25 Hz respectively, with standard deviations of 1.4% and 1.25%. The performance of the device has been determined by measuring the effective deflection at each frequency cycle. The experimental characterization of the fabricated micropump has shown a maximum flow rate of 42 μL/s at an optimum operating frequency of 3 Hz.