Fractional Order Strain Feedback for Oscillation Damping of a Multi-Elastic-Link Arm Under Gravity

Abstract:
Common modeling approaches for elastic link robots involve a discretization or truncation of the actually infinite dimensional plant dynamics. Oscillation damping controllers resting upon such models likely excite the neglected dynamics, which endangers the closed loop stability. The paper presents a wavebased control concept, which circumvents any truncation or discretization and provides experimental results for a multi-link arm. The proposed approach is referenced against an existing feedback scheme relying on a truncated dynamics model. The comparison is based on experiments within the entire workspace of a multi-link experimental setup and considers payload changes as well as external disturbances.