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Design of a simple active controller to suppress helicopter air resonanceA coupled rotor/fuselage helicopter analysis with the important effects of blade torsional flexibility, unsteady aerodynamics, and forward flight is presented. Using this mathematical model, a nominal configuration is selected that experiences an air resonance instability throughout most of its flight envelope. A simple multivariable compensator using conventional swashplate inputs and a single body roll rate measurement is then designed. The controller design is based on a linear estimator in conjunction with optimal feedback gains, and the design is done in the frequency domain using the Loop Transfer Recovery method. The controller is shown to suppress the air resonance instability throughout wide range helicopter loading conditions and forward flight speeds.
Document ID
19890031506
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Takahashi, M. D.
(California Univ. Los Angeles, CA, United States)
Friedmann, P. P.
(California, University Los Angeles, United States)
Date Acquired
August 14, 2013
Publication Date
January 1, 1988
Subject Category
Aircraft Design, Testing And Performance
Meeting Information
Meeting: Annual Forum of the AHS
Location: Washington, DC
Country: United States
Start Date: June 16, 1988
End Date: June 18, 1988
Sponsors: AHS
Accession Number
89A18877
Funding Number(s)
CONTRACT_GRANT: NAG2-209
CONTRACT_GRANT: NAG2-477
Distribution Limits
Public
Copyright
Other

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