0
RESEARCH PAPERS

Cancellation of Discrete Time Unstable Zeros by Feedforward Control

[+] Author and Article Information
Eric Gross, Masayoshi Tomizuka, William Messner

Department of Mechanical Engineering, University of California, Berkeley, Berkeley, CA 94720

J. Dyn. Sys., Meas., Control 116(1), 33-38 (Mar 01, 1994) (6 pages) doi:10.1115/1.2900678 History: Received March 26, 1992; Revised October 20, 1992; Online March 17, 2008

Abstract

This paper presents a design methodology for the cancellation of unstable zeros in linear discrete time systems with tracking control objectives. Unstable zeros are defined to be those zeros of the rational transfer function that occur outside the unit circle. Unstable zeros cannot be canceled by feedback without compromising stability. In light of this fact, a feedforward scheme is used. Future desired trajectory information is required because the feedforward scheme is noncausal. The amount of future desired trajectory information that is required depends upon the zero locations and design specifications. It is shown that for a known plant with no zeros on the unit circle one can obtain a frequency response arbitrarily close to 1. Robustness issues and simulation results are discussed.

Copyright © 1994 by The American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In