Water Driven Soft Actuator

In this paper, a water driven soft actuator is introduced. Soft actuators driven by various external stimuli, such as air pressure, temperature, pH, electric field, and light have been reported in the past. Although they are very attractive, they often require hard external devices for driving and the response speeds are often slow. The developed water driven actuator was with sodium polyacrylate wrapped by stretchable meshed nylon. Through some experiments, it was confirmed that swell and shrink phenomena of the developed device occur depending on the fluid flow. The phenomena could be found when adequate quantity of sodium polyacrylate was inside of the nylon. The amount of sodium polyacrylate that is required for the phenomenon was investigated. Through the experiments, it was confirmed that the displacement and the response speed of the swell and shrink were large and fast, respectively, in spite of its simple implementation.