Design of an IPMC diaphragm for micropump application

Abstract

Micropumps have gained a great potential to be applied as biomedical devices and micro systems. Because of low driven voltage, flexible operation, and self sensing ability, the ionic polymer metal composite (IPMC) material has been used as diaphragm of micropumps. This paper presents a novel design of IPMC diaphragm which helps to produce larger deformation and increase the durability of IPMC actuator. Unlike the conventional design of using a single piece of IPMC material clamped at all edges, we use several IPMC actuators (clamped at single edge) to drive elastic thin films. By eliminating the edge constrains for IPMC actuators, the new diaphragm can provide significantly larger deformation. Moreover, new design separates the IPMC from the pumping fluid and thus allows solvent to cover the IPMC and maintain long operating duration.An incorporation of physical induced stress model of IPMC actuators and the visual ANSYS environment is proposed to analyze the characteristic of the proposed diaphragms in comparison with the conventional one. Experiments have also been carried out to demonstrate the effectiveness of proposed model. Experimental results show that the new diaphragm design can produce deformation up to 0.4mm and maintain stable operation over 35min corresponding to a 3V–0.05Hz input signal, while the conventional design can produce only 0.2mm in deformation and the pumping performance decreases rapidly after 8min.