Control of a Large Space Structure Using Direct Output Feedback and Modal Suppression.

Abstract

Direct output feedback control using one or two controllers is applied to the NASA Ground Test Facility offset antenna model. This is a test structure designed to have the vibration characteristics associated with large space structures. The control problem is transformed from physical variables into modal variables and reformulated into a first order system. This system is truncated to a reduced order model with residual modes used only in performance evaluation. Optimal linear equadratic regulator techniques are used to design the gain matrices and full state feedback is approximated by use of generalized inverses of the observation matrices. Spillover is eliminated through the use of transformation matrices. The structure is shown to be controllable with this method. Alternative sensor placement is explored and found to cause improvement in performance. The torsion modes are found to be particularly important to the performance of the structure but need more sensing and actuation to be adequately controlled. Two controller systems require more sensors and actuators than available to achieve acceptable performance with this structure. keywords: Flexible space structures; Model reduction; Modal analysis. (Theses).

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1985
Accession Number
ADA163960

Entities

People

  • Eric E. Keller

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • Cyber
  • Sensors

DTIC Thesaurus Topics

  • Actuators
  • Air Force
  • Classification
  • Closed Loop Systems
  • Computer Programs
  • Computers
  • Control Systems
  • Differential Equations
  • Eigenvalues
  • Feedback
  • Large Space Structures
  • Modal Analysis
  • Observation
  • Resonant Frequency
  • Test And Evaluation
  • Test Facilities
  • Vibration

Readers

  • Adaptive Control and Estimation with Uncertainty in Dynamic Systems.
  • Robotics and Automation.
  • Structural Dynamics.

Technology Areas

  • Space
  • Space - Spacecraft Maneuvers