Impedance Control of Series Elastic Actuators Using Acceleration Feedback

More and more robots are designed to help or substitute humans both in daily activities and dangerous scenarios. These robots should be able to cope with humans and with other robots and to move in houses, factories, hospitals and uncertain outdoor terrains. To accomplish these targets robots must be able to move safely in unstructured or uncertain environments and to display relatively high forces with high dynamical precision. Currently a widespread solution is that of using impedance controlled elastic joint robots. While impedance control allows to safely deal with unknown kinematic and dynamic environmental constraints, series elastic joints allows impedance controllers to be implemented on high force and high power density motors. This is because accurate impedance control is often implemented relying on a explicit inner force loop and series compliance can dramatically improve explicit force control robustness.