Modal parametric identification of flexible mechanical structures in mechatronic systems

Abstract

To shorten the development and production time of mechatronic systems, an integrated servo-mechanical design procedure combining mechanical structure prototyping and fast servo evaluation is essential. In this paper, a modal parametric identification procedure is developed for estimation of residues, damping ratios, and natural frequencies of resonant modes for linear-time-invariant flexible mechanical systems. The coefficients and residues of the transfer function model are optimized via two subsequent least squares error optimization criteria in modal summation form. The proposed methodology is verified with experimental frequency responses measured from a commercial dual-stage hard disk drive using a laser Doppler vibrometer. Our results show the effectiveness and robustness of the proposed system identification algorithm for estimating the modal parameters of flexible mechanical structures in mechatronic systems.