Patent ID: 7900869

Claim:
An individual blade control system for controlling rotor pitch in a helicopter control system, the helicopter control system including pilot controls for generating pilot control inputs directing operation of a rotor assembly including a plurality of blades mounted to a rotor hub supported by a rotating shaft and a blade actuator responsive to the pilot control signals and coupled to the rotor assembly for controlling pitch of the blades, the individual blade control system comprising: at least one blade dynamics sensor for generating at least one blade dynamics signal representing a corresponding blade dynamics factor, a plurality of individual blade actuators, each blade actuator corresponding to a blade and controlling pitch of the corresponding blade, and a blade pitch controller, including an inner control loop for each blade for blade pitch position control by matching an actual pitch position of the blade actuator to a commanded actuator pitch position by comparing an actuator pitch position output representing the actual stroke position of the blade actuator with the corresponding commanded actuator pitch position and generating a corresponding corrected actuator position output to the blade actuator, and an outer control loop for reducing control loads on the blade actuators, including a system identification mechanism receiving the at least one blade dynamics signal and generating modeled outputs representing a linear T-matrix model of the helicopter control system, and a controller mechanism generating a commanded actuator stroke position output for each blade actuator, including an outer loop processor receiving flight control commands and the modeled outputs of the system identification mechanism and generating a commanded stroke output for each individual blade actuator, each commanded stroke output including a flight control command component and a control load reduction component.