US 10,890,668 B2
System and method for determining a velocity of a rotorcraft
Robert Earl Worsham, II, Weatherford, TX (US); Charles Eric Covington, Colleyville, TX (US); and Thomas Wayne Brooks, Grapevine, TX (US)
Assigned to Textron Innovations Inc., Providence, RI (US)
Filed by Textron Innovations Inc., Providence, RI (US)
Filed on Jun. 28, 2018, as Appl. No. 16/22,455.
Prior Publication US 2020/0003908 A1, Jan. 2, 2020
Int. Cl. G01S 19/52 (2010.01); B64C 13/50 (2006.01); G01C 21/16 (2006.01); G01S 19/14 (2010.01)
CPC G01S 19/52 (2013.01) [B64C 13/503 (2013.01); G01C 21/16 (2013.01); G01S 19/14 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method of operating a rotorcraft, the method comprising:
receiving a GPS carrier signal by a GPS sensor of the rotorcraft;
determining, by the GPS sensor, a groundspeed of the rotorcraft based on a Doppler shift of a received frequency of the GPS carrier signal;
receiving, by an attitude and heading reference system (AHRS) of the rotorcraft, acceleration data from an inertial sensor of the AHRS;
receiving, by the AHRS, an indication of groundspeed from the GPS sensor;
determining, by the AHRS, a velocity based on the groundspeed and the acceleration data;
receiving, at a flight control computer (FCC) of the rotorcraft, an indication of the velocity from the AHRS, determining, by the FCC, an actuator command based on the velocity; and
transmitting, by the FCC, the actuator command to a flight control device of the rotorcraft to control the flight control device according to the actuator command.