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We propose a new strategy for dielectric elastomers based on three dimensional electrodes (in liquid, gel, and solid states) created by microstructured networks of pillar arrays. We demonstrate fabrication through the use of existing MEMS electroding technology and soft nanolithography techniques. The dielectric elastomer transducers can be configured for capacitive sensing or electrostatic actuation. In the proposed work, integrated microstructures form a network of soft microcapacitor arrays driven by rational combinations of liquid electronic conductors, ionic conducting gels, ionic conducting liquids, and stretchable metallic films. Fluid electrodes are a viable consideration for encapsulated material systems such as the one considered here. Micropillar arrays are fabricated using a soft nanolithography technique whereby the pillar structure is electroded with sputtered gold and eutectic Gallium–Indium (EGaIn) liquid metal. This creates a novel configuration whereby the working electrodes are integrated within the structure itself. We utilize an electrochemical technique to coat the cilia-like micropillar surface with EGaIn. The electroded micropillars enable large sensor stretches up to 60%. When configured for actuation, the array generates macroscopic deformations in response to lower voltages (< 1kV) than typically prescribed for dielectric elastomers (i.e. 2kV – 10 kV). When configured for sensing, our results show increased sensitivity in comparison to monolithic DE sensors. The micropillar sensor has high sensitivity (1.2 kPa-1) in the tactile sensing regime (<10kPa). We employ an experimental approach to investigate the influence of pillar size, shape, and aspect ratio on electromechanical performance. This paper presents characteristics of the sensing and actuation response.
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