Optimal selection of manipulator impedance for contact tasks

Abstract

This paper addresses position and force control of robotic manipulators that are in contact with environments that exhibit mechanical impedances covering a large continuous range, from very soft to very stiff. For robot programming, automation, teleoperation and haptics, such environments enforce a trade-off between position and force control, which can be accommodated by impedance controllers. In this work, we extend the concept of duality and consider impedance matching in order to optimise a combined position and force trajectory error metric. The analysis of numerical optimisation results provides clear guidance on the choice of target impedance parameters, based on environment and manipulator dynamics.