A novel actuator system featuring electric-responsive water layers: Preliminary experimental results

• We proposed a novel electric-responsive water layer actuator system.
• The proposed actuator system consists of electrodes and water.
• Salient characteristics such as response time, hysteresis and displacement controllable range are experimentally measured.
• The actuating force is estimated through a simple mechanical calculation.
• The influence of evaporation on actuating performance is evaluated by experiment
• In order to demonstrate the micro-displacement tracking performance of the proposed actuator, a proportional-integral-derivative controller is designed.
• The effectiveness of excellent tracking performance is validated by experiment.

This article presents a novel electric-responsive actuator which is discovered from one of nature phenomena. The proposed actuator is water itself which can convert electric energy into mechanical energy. Since the proposed actuator is activated by applying electric voltage to the water layer, it is called an electric-responsive water layer actuator (ERWLA in short) system. The micro-mechanism of this actuator system is based on the interaction between electric energy and the polarity of water which causes the flow of water, and subsequently generates mechanical motion. With this micro-mechanism, we can create actuating force to modulate dynamic motion using two hydrophobic materials featured by different properties of wettability. To demonstrate the effectiveness of the proposed ERWLA mechanism, actuating characteristics such as response time, maximum variation of displacement are evaluated. In addition, using a proportional-integral-derivative (PID) controller associated with the proposed actuator, control experiments are undertaken showing excellent displacement trajectory tracking control performance in micrometer range.