Buckling of Dielectric Elastomeric Plates for Soft, Microfluidic Pumps

Citation:

Tavakol, B. ; Bozlar, M. ; Froelicher, G. ; Stone, H. A. ; Aksay, I. A. ; Holmes, D. P. Buckling of Dielectric Elastomeric Plates for Soft, Microfluidic Pumps. In Society of Engineering Science ASME-AMD - Summer Meeting; Providence, RI, 2013.

Date Published:

July

Abstract:

Buckling of plates and rods are often avoided in design of structures; however, proper implementation of these
instabilities lead to advanced material functionality. In this work, we use the buckling of circular plates for pumping
fluids with a specific flow rate. Dielectric elastomers have been widely used in many applications such as soft
robotics, opto-electro-mechanical systems, and energy harvesting devices due to their unique mechanical and
electrical properties as well as their ability to convert electrical signals to mechanical actuations and vice versa. If we
confine a thin dielectric elastomeric plate at its edge and expose it to an electric field, it will undergo buckling. When
embedded within a microfluidic device, the out-of-plane deformation can be used as a pumping mechanism to inject
the fluids above or below the plate into channels. In order for the device to be compatible with fluids, the dielectric
film was sandwiched between two thin, flexible, solid electrodes that can not only be in direct contact with fluids, but
also undergo significant deformation without losing their functionality. We conducted experiments to quantify the
voltage-induced buckling instability and measured the flow rate as a function of voltage. In addition, the effect of
other boundary conditions such as volume and pressure difference between two sides of the thin film was investigated.
We also show that these pumps can be used in series and/or parallel to enhance the flow rate besides the pump
efficiency. Finally, we offer an analytical prediction that uses plate buckling theory to estimate the critical voltage for
buckling of confined dielectric plates.

Last updated on 08/21/2017