Drone equipped with a video camera sending sequences of images corrected for the wobble effect

Patent metadata

Field	Value
Publication number	US-10165185-B2
Application number	US-201615333014-A
Country	US
Kind code	B2
Filing date	Oct 24, 2016
Priority date	Nov 23, 2015
Publication date	Dec 25, 2018
Grant date	Dec 25, 2018

Abstract

The drone comprises a camera (14) having a rolling shutter digital sensor which sends video data (l) line by line. An inertial unit (26) sends a gyrometric signal representative of the variations in attitude (φ, θ, ψ) of the camera at a given instant. An image processing module (30) comprising an anti-wobble module receives the video data (l) and the gyrometric signal as inputs, and outputs video data processed and corrected for artifacts introduced by the vibrations of the motors of the drone. A complementary filtering module (36) applies a predetermined compensating transfer function to the gyrometric signal at the input of the anti-wobble module, which transfer function is an inverse transfer function of the frequency response of the gyrometric sensor of the inertial unit.

First claim

The invention claimed is:

1. A drone, comprising:
a camera comprising a lens, a digital sensor on which an image of a landscape is formed, and a rolling shutter mechanism for reading the digital sensor, which outputs video data line by line;
an inertial unit, comprising a gyrometric sensor capable of measuring variations in attitude of the drone and of outputting a gyrometric signal representative of rotations of the drone at a given instant relative to a given point of reference; and
an image processing module, comprising an anti-wobble module which receives the video data and the gyrometric signal as inputs, and outputs video data processed and corrected for artifacts introduced by vibrations produced by the drone,

wherein the drone further comprises, at the input of the image processing module:
a complementary filtering module which is capable of applying a predetermined compensating transfer function to the gyrometric signal at the input of the anti-wobble module, said predetermined compensating transfer function being an inverse transfer function of frequency response of said gyrometric sensor of the inertial unit.

2. A method for correcting a wobble artifact introduced by vibrations produced by a drone in a digital image received by a rolling shutter digital sensor of a camera of said drone,
in which the drone comprises an inertial unit comprising a gyrometric sensor capable of measuring variations in attitude of the drone and of outputting a gyrometric signal that is representative of rotations of the drone at a given instant relative to a given point of reference,
the method comprising:
a) in a preliminary step:
a1) measuring frequency response of said gyrometric sensor of the inertial unit;
a2) generating a digital filter having an inverse compensating transfer function of said frequency response of the gyrometric sensor; and
a3) loading said digital filter into a complementary filtering module at the input of an anti-wobble module of the drone, and

b) during operation of the drone, continuously and in real time:
b1) receiving the gyrometric signal sent by the inertial unit of the drone;
b2) applying the compensating transfer function loaded into the digital filter in step a3) to the gyrometric signal received in step b1); and
b3) applying the gyrometric signal filtered in step b2) to the anti-wobble module of the drone.

Assignees

• Parrot Drones

Inventors

• Eline Pierre

Classifications

• B64U2101/30

  for imaging, photography or videography · CPC title

• H04N23/6812 Primary

  based on additional sensors, e.g. acceleration sensors · CPC title

• H04N23/683

  performed by a processor, e.g. controlling the readout of an image memory · CPC title

• B64D47/08

  Arrangements of cameras · CPC title

• H04N5/23258 Primary

  Electricity · mapped topic