Individual blade control for alleviation of helicopter ground resonance

摘要

Individual blade control (IBC) through blade root pitch actuation in the rotating system, based on rotor state feedback, is investigated as a means to alleviate ground resonance instability. ^Formal optimization techniques are used on two different model rotors to determine a combination of controller gains, for each rotor, that will alleviate resonance over a broad range of conditions. ^For both model rotors considered, IBC stabilized ground resonance over a wide range of rotational speeds and collective pitch values. ^The robustness of these IBC schemes is verified by their continued effectiveness in case of changes in fuselage inertia. ^IBC is shown to have a greater stabilizing effect on ground resonance than either aeroelastic couplings or active control through the swashplate based on fuselage state feedback. ^The optimized IBC used to alleviate ground resonance was found to improve aeromechanical stability in hover. ^(Author)