Accession Number : AD0784190

Title :   Experimental Verification of System Identification.

Descriptive Note : Final rept.,

Corporate Author : KAMAN AEROSPACE CORP BLOOMFIELD CONN

Personal Author(s) : Flannelly,W. G. ; Giansante,N.

Report Date : AUG 1974

Pagination or Media Count : 95

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 antiresonances 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. (Modified author abstract)

Descriptors :   *HELICOPTERS, *SYSTEMS ANALYSIS, *DYNAMIC RESPONSE, SYSTEMS ENGINEERING, IDENTIFICATION, EXPERIMENTAL DATA, CORRELATION TECHNIQUES, MASS, STIFFNESS, SHAKING, MODEL TESTS, DAMPING, COEFFICIENTS, MATHEMATICAL MODELS, DEGREES OF FREEDOM, MATRICES(MATHEMATICS)

Subject Categories : Helicopters
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE