VALIDITY OF DESCRIBING-FUNCTION TECHNIQUES FOR THE ANALYSIS OF THIRD-ORDER RELAYOPERATED SERVOMECHANISMS.

Abstract

The relay-operated servomechanism oscillates at finite amplitudes and frequencies with its input equal to zero. These amplitudes and frequencies can be predicted by a special technique which replaces the relay by a quasilinear model called the describing function. To gain confidence and understanding in this type of technique, an analog computer was used to obtain exact solutions for the system and these were compared to solutions obtained by the describing function technique. In this thesis the solution comparisons are presented in a graphical form along with relay characteristic gain-phase plots, motor load gain-phase plots and an explanation of the describing function technique. Describing function predictions were found to be within ten percent of computer solutions for the great part, however, in the region of incipient oscillation results were consistantly poor. (Author)

Document Details

Document Type
Technical Report
Publication Date
May 20, 1957
Accession Number
AD0620597

Entities

People

  • Gerald Wayne Meisenholder

Organizations

  • Massachusetts Institute of Technology

Tags

DTIC Thesaurus Topics

  • Amplitude
  • Analog Computers
  • Computers
  • Computing Devices
  • Frequency
  • Oscillation
  • Servomechanisms

Readers

  • Control Systems Engineering.
  • Regression Analysis.
  • Theoretical Analysis.