Patent ID: 6322324
Filing Date: 2001-11-27
Classification: B64C,Y02T,Y10S

Abstract:
A system for quasi-statically correcting tracking of a rotor blade of a helicopter rotor during operation, comprising:a trim tab mounted on the rotor blade and deflectable relative to the rotor blade so as to change a tracking path of the rotor blade;a rotor track and balance analyzer that includes sensors for acquiring rotor tracking and balance information and is operable to process said rotor tracking and balance information so as to predetermine a new tab position to which the trim tab should be deflected for bringing the tracking path of the rotor blade into alignment with a reference path;an actuator mounted to the rotor blade, the actuator having an actuating element coupled with the trim tab and formed of a smart material such that the actuating element deforms proportional to a stimulus applied to the actuating element, the actuator further including stimulus means for applying a stimulus to the actuating element upon supplying electrical power to said stimulus means, whereby the actuator deflects the trim tab when electrical power is supplied to the actuator;an electrical locking device operable when de-energized to lock the trim tab against deflection, and operable when energized to unlock to permit the trim tab to be deflected; anda trim actuation control system in communication with the rotor track and balance analyzer and the locking device, the trim actuation control system being arranged to energize the locking device and to supply electrical power to the actuator so as to deflect the trim tab to the new tab position predetermined in the rotor track and balance analyzer, and to then de-energize the locking device and cut off the electrical power to the actuator, the locking device fixing the trim tab in the new tab position.