Development of Small-Sized Digital Servo Valve for Wearable Pneumatic Actuator

Recently, power assisted nursing care systems have received much attention and those researches have been done actively. In such a control system, an actuator and a control valve are mounted on the human body. Designing the system, the size and weight of the valve become serious concerns. At the same time, the valve should be operated with lower energy consumption because of the limited electrical power. The purpose of our study is to develop a small-sized, lightweight and lower energy consumption control valve. In our previous study, a new type of fluid control valve with a self-holding function using a permanent magnetic ball in a check valve, a cylindrical magnet and two solenoids was also proposed and tested. In this study, a digital servo valve with self-holding function is proposed and investigated experimentally. As a result, we can confirm that the tested digital servo valve can control the output flow rate in both supply and exhaust with low energy consumption.