Development and control of 1-DOF manipulator using electrostrictive rubber actuator

Recently, flexible and light actuators that mimic muscle fibers have been actively researched. Here, we focused on an electroactive polymer (EAP) dielectric elastomer. To construct the actuator, the dielectric elastomer is rolled into a tube, and extended by applying a voltage across its electrodes. In this paper, we experimentally obtained a static characteristic model of the electrostrictive rubber actuator, and proposed a control method. We then incorporated the actuator into a 1-DOF manipulator, and constructed a controller from a mechanical equilibrium model of this manipulator. Finally, the constructed controller was tested in a series of experiments. The angle of the arm fell below the desired angle because of friction in the joint and the spring characteristics of actuators. However, we confirmed that the controller reduced the influence of the load by torque feedback. We also investigated the influence of joint stiffness.