Characterisation of Self-locking High-contraction Electro-ribbon Actuators^*

Actuators are essential devices that exert force and do work. The contraction of an actuator (how much it can shorten) is an important property that strongly influences its applications, especially in engineering and robotics. While high contractions have been achieved by thermally- or fluidically-driven technologies, electrically-driven actuators typically cannot contract by more than 50%. Recently developed electro-ribbon actuators are simple, low cost, scalable electroactive devices powered by dielectrophoretic liquid zipping (DLZ) that exhibit high efficiency (~70%), high power equivalent to mammalian muscle (~100 W/kg), contractions exceeding 99%. We characterise the electro-ribbon actuator and explore contraction variation with voltage and load. We describe the unique self-locking behaviour of the electro-ribbon actuator which could allow for low-power-consumption solenoids and valves. Finally, we show the interdependence of constituent material properties and the important role that material choice plays in maximising performance.