Multi-variable velocity feedback controller for piezoelectric tube scanner: A “mixed” negative-imaginary and small-gain approach

摘要

This paper presents the design and implementation of a multi-input multi-output (MIMO) velocity feedback controller (VFC) based on a recent theoretical results on “mixed” negative-imaginary and small-gain approach to damp the first resonant mode of a piezoelectric tube scanner (PTS) used in atomic force microscopes (AFMs). The identification of the MIMO dynamics of the PTS is done by using the measured data and the “mixed” negative-imaginary and small-gain approach is used to establish the internal stability between the PTS and the velocity feedback controller. Experimental results are presented to demonstrate the effectiveness of the proposed controller.