Micro pneumatic valves for wearable robotic systems

This paper describes small-sized pneumatic valves applicable to wearable robotic systems. Pneumatic actuators, especially McKibben actuators and balloon actuators, have been utilized in wearable robotic systems. Although these actuators are light in weight, their control valves are heavy and bulky, hindering the performance of wearable systems. Compact control valves to drive pneumatic actuators are therefore needed. Miniaturized unconstrained valves are novel pneumatic control valves, which, together with their driver circuits (PZT drivers), can drive pneumatic actuators. We have developed miniaturized valves and PZT drivers. A prototype valve 7mm in radius and 9mm in height was capable of controlling 0.5 MPa pressure with 3 l/min flow. Experiments performed to evaluate the developed system showed that these miniaturized unconstrained valves could drive a robotic finger and a manipulator.