Elastomer-based electroadhesion can be an effective method to provide tunable adhesion between robots and grasped objects or surfaces. However, there has been little work to develop models of electroadhesion and characterization of adhesive performance relative to these models. In this paper, a basic friction model is proposed to describe the critical shear force for a single electrode electroadhesive fabricated from conductive PDMS encased in parylene. The use of parylene results in thin dielectrics that require only tens of Volts to achieve shear pressures greater than 100 kPa. The experimental results gathered by characterizing voltage, dielectric thickness, adhesive area, and adhesive thickness follow the trends predicted by theory with some important deviations that are studied using high speed video capture of the soft adhesive failure.

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For electroosmotic pumping, a large direct-current (DC) electric field (10+ V/cm) is applied across a liquid, typically an aqueous electrolyte. At these high voltages, water undergoes electrolysis to form hydrogen and oxygen, generating bubbles that can block the electrodes, cause pressure fluctuations, and lead to pump failure. The requirement to manage these gases constrains system designs. This article presents an alternative polar liquid for DC electrokinetic pumping, propylene carbonate (PC), which remains free of bubbles up to at least 10 kV/cm. This offers the opportunity to create electrokinetic devices in closed configurations, which we demonstrate with a fully sealed microfluidic hydraulic actuator. Furthermore, the electroosmotic velocity of PC is similar to that of water in PDMS microchannels. Thus, water could be substituted by PC in existing electroosmotic pumps.

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