Patent ID: 8021115
Filing Date: 2011-09-20
Classification: B64C,F16F,Y10S

Abstract:
1. A rotary-wing aircraft rotor system which rotates about an axis of rotation, comprising: a rotor system having an N number of blades which rotates about an axis of rotation at a rotational speed of 1 P, such that said main rotor system produces NP vibrations; a sensor system which senses the NP vibrations; a multiple of masses coaxially disposed with said rotor system; a drive system to independently spin each of said multiple of masses about said axis of rotation at an angular velocity; a control system in communication with said sensor system and said drive system, said control system operable to identify variations of the NP vibrations to control an angular velocity of at least one of said multiple of masses to reduce the NP in-plane vibrations; and a generator driven by said main rotor system which powers an electric motor of said drive system, each of said multiple of masses driven by an electric motor, a phase of the voltage from said generator providing a phase reference to said control system indicative of a rotational speed of said main rotor system.