Comparison of Pointing Control Systems Utilizing Dahl and Coulomb Friction Model Compensation

Abstract

Bearing friction can be accurately modeled using the Coulomb friction model, provided the bearing is running. In an application where the bearing is rotated only a very small amount, the bearing does not actually rotate. Instead, the bearing undergoes plastic deformation. A nonlinear friction model was developed by P. R. Dahl of the Aerospace Corporation in the late sixties which addresses this region of placticity or compliance zone. Two friction compensation schemes for a single axis position servomechanism were developed and compared in this study. The first compensator was an integral control regulator/estimator which used the Coulomb friction model. The second, more complicated compensator, was an extended Kalman filter (EKF) design which used the DAHL friction model. The compensator designs were simulated using ProMatlab. Comparisons were made of the time response characteristics to determine if any increases in performance were worth the added complexity of the Dahl model EKF controller. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1991
Accession Number
ADA244266

Entities

People

  • Whitney J. Hulett

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • Space
  • Weapons Technologies

DTIC Thesaurus Topics

  • Bearings
  • Compensation
  • Control Systems
  • Estimators
  • Feedback
  • Filters
  • Frequency
  • Friction
  • Integrals
  • Kalman Filters
  • Mainframe Computers
  • Measurement
  • Moment Of Inertia
  • Regulators
  • Servomechanisms
  • Simulations
  • Square Waves

Fields of Study

  • Engineering

Readers

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

Technology Areas

  • Space
  • Space - Spacecraft Maneuvers