Adaptive Servo Control of Large Antenna Structures

  • R. J. Evans
  • I. M. Y. Mareels
  • L. J. Seiacea
  • D. N. Cooper
  • R. H. Middleton
  • R. E. Betz
  • R. A. Kennedy
Chapter

Abstract

This contribution considers the design of servo tracking loops for large antennae structures which exhibit lightly damped flexible modes. A cascaded loop control structure employing performance oriented adaptive feedforward in the outer loop is developed. The procedures for designing the inner current (motor drive), rate loop and position loop as well as the adaptive feedforward compensator are presented. It is demonstrated that this constitutes a practical and robust solution to the problem of controlling servo tracking systems in the presence of non trivial resonances. The control structure provides excellent tracking of parabolic trajectories as well as disturbance rejection. The conclusions are supported by analysis, simulation, and experimental results on 22m, 26m and 64m radio-astronomy and telecommunication antennae across Australia.

Keywords

Reference Trajectory Disturbance Rejection Gear Train Wind Disturbance Torque Disturbance 
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Copyright information

© Springer-Verlag London Limited 2001

Authors and Affiliations

  • R. J. Evans
    • 1
  • I. M. Y. Mareels
    • 1
  • L. J. Seiacea
    • 2
  • D. N. Cooper
    • 3
  • R. H. Middleton
    • 4
  • R. E. Betz
    • 4
  • R. A. Kennedy
    • 5
  1. 1.Department of Electrical and Electronic EngineeringThe University of MelbourneUSA
  2. 2.Tenix Defence SystemsMawson LakesUSA
  3. 3.Formerly Division of Telecomms and Industrial Physics CSIROAustralia
  4. 4.Department of Electrical and Computer EngineeringThe University of NewcastleAustralia
  5. 5.Department of Telecommunications, Research School of Information Sciences and EngineeringThe Australian National UniversityAustralia

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