A novel diaphragm micropump actuated by conjugated polymer petals: Fabrication, modeling, and experimental results

Micropumps have promising applications in biomedical devices and micro total analysis systems. Conjugated polymer actuators provide an important potential mechanism for realizing micropumps because of their amenability to miniaturization and low actuation voltages. In this paper we present a novel, conjugated polymer petal-actuated diaphragm micropump, which is in contrast to the typical diaphragm design of using a single piece of soft actuation material clamped at all edges. We show through analysis and experiments that the new design, by alleviating the edge constrains, can provide significantly larger diaphragm deformation and consequently higher flow rate. A physics-based, control-oriented model is developed to predict the diaphragm deformation and the flow rate given the actuation voltage input. Experiments conducted on a polypyrrole (PPy)-actuated micropump, fabricated through PDMS-based MEMS processes, have validated the dynamic model. A maximum flow rate of 1260 mu L/min is achieved for the petal-actuated diaphragm pump under an actuation voltage of 4 V. while in comparison, the pump with traditional diaphragm design generates no observable flow under the same voltage. (C) 2009 Elsevier B.V. All rights reserved.