Patent ID: 8435002

Claim:
A rotary blade rotating hub mounted rotating assembly vibration control system for a rotary blade rotating hub assembly experiencing a vibration of a plurality of vibration frequencies while rotating at an operational rotation frequency about a rotating assembly center axis of rotation, said rotating assembly vibration control system comprising: a first imbalance mass concentration rotor, a second imbalance mass concentration rotor, a third imbalance mass concentration rotor, and a fourth imbalance mass concentration rotor, said first imbalance mass concentration rotor having a first imbalance mass concentration rotor center axis rotation centered on said rotating assembly center axis of rotation, said second imbalance mass concentration rotor having a second imbalance mass concentration rotor center axis rotation centered on said rotating assembly center axis of rotation, said third imbalance mass concentration rotor having a third imbalance mass concentration rotor center axis rotation centered on said rotating assembly center axis of rotation, said fourth imbalance mass concentration rotor having a fourth imbalance mass concentration rotor center axis rotation centered on said rotating assembly center axis of rotation, said first imbalance mass concentration rotor and said second imbalance mass concentration rotor driven at a first rotation speed greater than said rotating assembly operational rotation frequency while controlling the rotational position of said first imbalance mass concentration and said second imbalance mass concentration to produce a first rotating net force vector to inhibit a first vibration frequency, said third imbalance mass concentration rotor and said fourth imbalance mass concentration rotor driven at a second rotation speed greater than said rotating assembly operational rotation frequency while controlling the rotational position of said third imbalance mass concentration and said fourth imbalance mass concentration to produce a second rotating net force vector to inhibit a second vibration frequency.