A Frequency Domain Identification Scheme for Flexible Structure Control

Abstract

Transfer function identification schemes for use in self-tuning control applications are considered. Frequency domain methods generally require less computational load than time domain methods, and for certain classes of systems may be more accurate. For control purposes, however, a time domain parameterization of the system transfer function is often preferred, because of the direct relationship to controller parameters. In this paper we present a new method called Time-varying Transfer Function Estimation (TTFE) in which system parameters are computed through identification in the frequency domain. The method is particularly well suited for flexible structure control problems, and a self-tuning control law with frequency shaping is derived and demonstrated on a flexible manipulator system.