Series Elastic Actuator Control Based on Active Damping Injection with Positive Torque Feedback

Abstract

The paper considers the control of serial elastic actuators (SEA) that have become a leading trend in the field of safe robotics and human-robot interaction. Many researchers in this field give particular attention to closed-loop impedance control. In particular, controlling the damping of substantially compliant SEA was considered by several authors in the last few years. One such approach is based on active damping injection that introduces a viscous friction term into the behavior of SEA spring via pure control action. The present paper proposes an extension of this approach that gives way to the explicit and simple tuning of the controller along with the well-defined behavior of the closed-loop system. For the proposed controller stability analysis and simulation studies are conducted.