Experimental Verification of System Identification

Abstract

Laboratory testing of helicopter system identification by single- point excitation showed correlation among the parameters identified by free-body shaking at two different points and theoretically derived parameters of the test specimen. Among the parameters investigated were the mass and stiffness matrices of five- and six-degree-of-freedom models and the structural damping coefficient of a continuous specimen. Experimentation demonstrated the identification of mathematical models having more degrees of freedom than modes in the measurements, a method of obtaining modal parameters by antiresonance theory, an engineering solution to the problem of imaginary antiresonance in Biot's Equation and Duncan's Equation for transfer impedances, a method of obtaining static influence coefficients by free-body testing without assumption of a mass matrix, and a method of determining static structural test loads of helicopter maneuvers.

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Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1974
Accession Number
AD0784190

Entities

People

  • N. Giansante
  • W. G. Flannelly

Organizations

  • Kaman Corporation

Tags

Communities of Interest

  • Advanced Electronics
  • Air Platforms
  • Ground and Sea Platforms
  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Accuracy
  • Aerospace Industry
  • Aircrafts
  • Center Of Gravity
  • Dynamic Response
  • Elastic Properties
  • Engineering
  • Engineers
  • Equations
  • Equations Of Motion
  • Frequency
  • Helicopters
  • Measurement
  • Resonant Frequency
  • Rotary Wing Aircraft
  • Static Tests
  • Test Equipment

Fields of Study

  • Engineering
  • Physics

Readers

  • Control Systems Engineering.
  • Tribology (the study of the boundary interaction between sliding surfaces, lubrication, wear and friction).