Rotary-wing drone comprising autonomous means for determining a position in an absolute coordinate system linked to the ground

摘要

The drone comprises: a vertical-view camera (132) pointing downward to pick up images of a scene of the ground overflown by the drone; gyrometer, magnetometer and accelerometer sensors (176); and an altimeter (174). Navigation means determine position coordinates (X, Y, Z) of the drone in an absolute coordinate system linked to the ground. These means are autonomous, operating without reception of external signals. They include image analysis means, adapted to derive a position signal from an analysis of known predetermined patterns (210), present in the scene picked up by the camera, and they implement a predictive-filter estimator (172) incorporating a representation of a dynamic model of the drone, with as an input the position signal, a horizontal speed signal, linear and rotational acceleration signals, and an altitude signal.