We made low-resistance electrodes for a dielectric elastomer system (DES) without the use of thin film deposition or wet lab processes by utilizing a stretchable conductive fabric, Less EMF Stretch Conductive Fabric (SCF), for electrode material. Carbon-based DES electrodes are easy to make, but they have high resistances (kilo ohms) that hamper dynamic operation and reduce energy efficiency. Metal and hydrogel DES electrodes have much lower resistances (tens to hundreds of ohms), but they require complex manufacturing processes, such as thin film deposition or wet lab synthesis. Conductive fabrics can have low resistance and they can be made into DES electrodes with merely a laser cutter and a dry lab environment, but their stiffness may hinder DES performance. This work reports electrical and mechanical properties of SCF and a more compliant, though less conductive fabric, MedTex P70+B, and describes the assembly and performance of DES variable stiffness modules using them. SCF had low sheet resistance, less than 3.0 ohm/square even during 125% biaxial stretch, and both fabrics stretched beyond 200 % uniaxial elongation before mechanical failure. The assembly of modules with conductive fabric electrodes was comparable in terms of difficulty to that with carbon powder electrodes, and produced functional modules. However, the stiffness of the fabrics diminished DES stiffness-reduction performance to merely 12.8 % and 13.4 % compared to the 24.5 % stiffness reduction a DES module with carbon powder electrodes achieved. Future work should investigate or develop more compliant conductive fabrics that would yield greater DES performance.
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