Fliud lens device construction and actuator performance based on electroactive polymers

http://tartu.ester.ee/record=b2655261~S1*es

A Kirigami Approach of Patterning Membrane Actuators

Ionic electroactive polymer actuators are typically implemented as bending trilayer laminates. While showing high displacements, such designs are not straightforward to implement for useful applications. To enable practical uses in actuators with ionic electroactive polymers, membrane-type film designs can be considered. The significantly lower displacement of the membrane actuators due to the lack of freedom of motion has been the main limiting factor for their application, resulting in just a few works considering such devices. However, bioinspired patterning designs have been shown to significantly increase the freedom of motion of such membranes. In this work, we apply computer simulations to design cutting patterns for increasing the performance of membrane actuators based on polypyrrole doped with dodecylbenzenesulfonate (PPy/DBS) in trilayer arrangements with a polyvinylidene fluoride membrane as the separator. A dedicated custom-designed device was built to consistently measure the response of the membrane actuators, demonstrating significant and pattern-specific enhancements of the response in terms of displacement, exchanged charge and force

Autofocus Fluid Lens Device with Implementation of Dielectric Electroactive Polymer Actuators

We produced an autofocus liquid lens based on meniscus changes of an oil/water interface caused by fieldinduced deformation of a dielectric elastomer stack actuator (DESA). The new DESA design integrated in the liquid lens is based on a circular actuator with a round hole in the middle (diameter: 4 mm) where the oil/water interface is located. Due to the surface tension between the two immiscible liquids (oil/water) a meniscus forms in proximity of the hole of the actuator membrane that can operate as a lens. The goal of this research was to apply and investigate encapsulated dielectric elastomer actuators (DEA) in liquid environments for producing a prototype autofocus lens. When the DEA membrane is applied a high voltage, the hole dimension changes by contraction of the DEA membrane, together with the curvature of the meniscus formed between oil and water. Consequently, the focus plane of a laser beam passing through the liquid lens changes. Configurations with DESA actuator or single-layered membranes are tested. Depending on the DEA membrane thicknesses (45 to 100 μm), the maximum applied voltage varied from 1150 to 2250 V