Development of a rodless type flexible pneumatic cylinder and its application

Abstract

Current virtual reality systems are not enough to realize a force feedback system for hands, arms, legs and so on. Furthermore, due to the ageing in Japanese society and the decreasing birthrate, an increasing problem of providing nursing care for the elderly has occurred. As a result, it is necessary to develop systems to aid in nursing care. The actuators required for such systems, need to be flexible so as not to injure the human body. The purpose of our study is to develop a flexible and lightweight actuator which can be safe enough to be mounted on the human body. In this paper, we proposed and tested rodless type of flexible pneumatic cylinder. The cylinder consists of a flexible tube as a cylinder or rod, steel balls as a piston and a duralumin slide stage that has balls and rollers. We investigated the characteristics of the tested cylinder. We also applied the tested cylinder as a rotary actuator of master-slave robot arm. As a result, we found that the tested cylinders had a "self holding function for positioning" under condition of no supply pressure. We confirmed that the tested cylinder was useful to apply as a wearable actuator with the advantages of flexibility, lightweight and easier positioning.