Development of intelligent McKibben actuator (1st report, realization of position servo system by soft displacement sensor)

This study aims at development of Intelligent McKibben actuator, in which micro displacement/ pressure sensors and micro valves are integrated. In this first report, development of rubber displacement sensor and its application to servo system using McKibben actuator are reported. Recently McKibben actuator attracts engineers because of light weight, high output power and high compliance. But in case of servo control using it, the systems need encoders or potentiometers, so the systems tend to grow in size and to take away from compliance at present. To solve thus problems, soft rubber sensor was developed, which was made of rubber covered its surface with conductive resin thinly. Electrical resistance of rubber sensor changes in response to extending motion of the rubber. We built the rubber sensor into McKibben actuator and named it Intelligent McKibben actuator. Servo system using single Intelligent McKibben actuator was realized, and tested. Furthermore, we fabricated a robot arm system configured by two Intelligent McKibben actuators. Experimental results showed that the actuator has good potential for realizing polymer-made intelligent actuator.