Improvements to LQGI/LTR Methodology for Plants with Lightly Damped or Low Frequency Poles

Abstract

LQG/LTR design has a tendency to invert the plant's dynamics, which is undesirable if there are plant poles near the imaginary axis. In this study, Static Output Feedback (SOF) is applied to reassign plant poles before LQG/LTR is applied. Alternatively, Robust Eigenstructure Assignment (REA) was used to design the target loop transfer function with an ideal eigenstructure to avoid the undesirable cancellations. Both methods were applied to several aircraft design problems. Results showed that the methods can be effectively used so that the LQG/LTR design has improved stability and performance; however, it was found that each method had strengths and weaknesses.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1992
Accession Number
ADA258841

Entities

People

  • An-chi Ju

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Aircrafts
  • Algorithms
  • Closed Loop Systems
  • Control Systems
  • Control Systems Engineering
  • Eigenvalues
  • Equations
  • Feedback
  • Flight Control Systems
  • Frequency
  • Frequency Bands
  • Frequency Domain
  • Kalman Filters
  • Linear Systems
  • Multiple Input Multiple Output
  • Transfer Functions
  • Unmanned Systems

Readers

  • Adaptive Control and Estimation with Uncertainty in Dynamic Systems.
  • Control Systems Engineering.
  • Systems Analysis and Design