Conventional electronics are typically rigid, introducing unwanted stiffness to otherwise entirely soft systems. Emerging soft and stretchable electronics provide a platform for integrating driving electronics in soft robotics and structures. A stretchable electrode having strain-dependent resistance is the dielectric elastomer switch (DES). The DES enables direct control of artificial muscles, or dielectric elastomer actuators (DEA), a popular material in soft robotics. Electromechanically interacting DEA and DES together make up smart actuator networks, with the DES as piezoresistive-charge gates. The DES is a unique stretchable electrode in that it directly couples mechanical strain with a logic state change. We have previously demonstrated logic gates and memory elements using DES/DEA arrays. Performance, particularly speed and cycle life, were limited due largely to acrylic-based, viscoelastic materials and hand-made fabrication process. Here we present computing elements with enhanced performance, comprising silicone membranes and airbrushed silicone-based electrodes. We also demonstrate a new model - a dielectric elastomer digital oscillator. The oscillator provides the timing signal for sequential logic elements, which reduces number of wires and inputs needed for DE circuits. Finally, we also use the mechanosensitive DES to implement adjustable frequency of the DE oscillators.
|