System identification and control of a flexible manipulator

Abstract

The Observabilty Range Space Extraction (ORSE) algorithm used to identify a an initially overparameterized discrete-time state-space model for a single-link flexible manipulator. A controller named PDPC is designed to control rigid body motion, have a zero tracking error and minimum vibration.--Abstract.

The Observability Range Space Extraction (ORSE) algorithm is successfully applied to identify an initially overparameterized discrete-time state-space model for a single-link flexible manipulator. Several critical issues related to the experiments and the implementation of the ORSE algorithm are addressed. A new model reduction and updating technique is proposed and applied to reduce the identified models. To quantify the contribution of individual modes to the responses, a new measure referred to as modal response magnitude (MRM) is developed and successfully applied to obtain a lower-order model by retaining the most significant modes. To correct errors caused by the model reduction, either the reduced input or output matrix is recalculated by a least squares solution. Based on the updated reduced-order models, a controller named as PDPC is designed to ensure a good tracking accuracy and robustness to payload changes. The experimental results show that the PDPC control structure is effective in controlling rigid body motion to have a zero tracking error and the minimum vibration as well.