Abstract
Soft rubber actuators have possibilities to be useful devices in medical, nursing care and hard work area because of their flexibility. Actually, rubber soft actuators are researched by many researchers. However, there are usually driven with air pressure that needs for preparing some equipment. We suggest that the rubber soft actuators, which are driven with gas/liquid phase change of working fluid. When the working fluid changed from liquid to gas, it takes huge volume change. We assume that this volume change is utilizable phenomenon as pressure source of rubber actuator. In addition to that, this volume change is easy to be excited by heating. We fabricate the prototype bending actuator of silicone rubber by molding using 3D printed ABS resin mold. 3D printed plastic dies can withstand the temperature when rubber is cured. We prepare two different softness rubbers and fabricate the prototype actuators. In the experiments, the actuators, which are filled with water and ethanol, are heated inside of the constant temperature reservoir by its atmosphere. As a results of experiments, we confirmed that the all actuators are bended as temperature increasing. We suppose that the actuator is driven with gas/liquid phase change, because the prototypes have no materials which can produce the pressure. We show that gas/liquid phase change phenomenon has the potentials for becoming tiny pressure source of rubber soft actuators.
