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On methods for application of harmonic control
16
Citations
0
References
1978
Year
Nonlinear ControlEngineeringAerospace EngineeringPitch ControlMechanical SystemsSystems EngineeringNonlinear Vibration ControlActive Vibration ControlControl DesignHarmonic ControlNasa ProgramRotor DynamicVibration ControlHigher HarmonicFlight Control
The paper presents data which confirm the effectiveness of higher harmonic blade pitch control in substantially reducing helicopter rotor vibratory hub loads. The data are the result of recent tests on a 2.7-m model conducted in the Langley Research Center's transonic dynamics wind tunnel. Several predictive analyses developed in support of the NASA program are shown capable of accurately predicting both amplitude and phase of the higher harmonic control input required to nullify a single 4/rev force or moment input. The use of multiple blade feathering inputs in the design of a flightworthy higher harmonic control system is discussed.