Real-time image motion correction or stabilization system and methods for projectiles or munitions in flight

Patent metadata

Field	Value
Publication number	US-10979643-B1
Application number	US-202016907593-A
Country	US
Kind code	B1
Filing date	Jun 22, 2020
Priority date	Feb 14, 2018
Publication date	Apr 13, 2021
Grant date	Apr 13, 2021

Abstract

The present invention relates to projectiles and munitions, and more specifically to such in flight. More particularly the present invention relates to projectiles and munitions in flight equipped with one or more image sensors adapted for acquiring image data of the environment surrounding the projection or munition in flight. The present invention further relates to systems and methods for correcting or stabilizing motion effects and artifacts present in the image data related to the movement or motion of the projectile or munition in flight, including spin or rotation of the projectile or munition.

First claim

The invention claimed is:

1. A real-time image motion correction or stabilization system for a projectile or munition in flight comprising:
a projectile or munition comprising at least one sensor adapted to acquire image data periodically or substantially continuously during flight of the projectile or munition, and a processor adapted to receive image data from the at least one sensor;
a feature selection algorithm comprised in the processor and adapted to identify at least two key features in the image data based on the image data acquired during flight of the projectile or munition;
a motion vector application algorithm comprised in the processor and adapted to apply vectors of motion corresponding to the at least two key features in the image data, the vectors of motion characterizing movement associated with the at least two key features within the image data;
a motion estimation algorithm comprised in the processor and adapted to estimate motion of the image sensor based on the vectors of motion corresponding to the identified at least two key features in the image data;
a stabilization algorithm comprised in the processor and adapted to correct or stabilize movement of the image data based at least in part on the vectors of motion and the estimated motion of the image sensor by shifting one or more images or frames of image data based at least in part on the estimated motion; and
at least one actuator adapted to activate and/or deactivate at least one activatable flow effector to guide the projectile or munition toward a target based at least in part on the corrected or stabilized image data.

2. The system of claim 1 , wherein motion of the image data exhibits an amplitude of 25 degrees or more and a frequency of 0.1 Hz or greater, and the processor and algorithms are adapted to perform the method on image data exhibiting such motion.

3. The system of claim 1 , wherein the processor is further adapted to send a command to the at least one sensor to switch focus of the image data from one of the at least two key features to another of the at least two key features while capturing image data.

4. The system of claim 1 , wherein the motion estimation algorithm is adapted to estimate motion of the image sensor by correlating a distance and direction of the movement associated with the at least two key features within the image data based at least in part on the vectors of motion.

5. The system of claim 1 , wherein the at least two key features identified are not the horizon and the at least one activatable flow effector is selected from the group consisting of wings, canards, strakes, spoilers, body fins, tailfins or vertical stabilizers, tailplanes or horizontal stabilizers, winglets, active vortex generators, flow deflectors, balloons, and microbubbles.

6. The system of claim 1 , wherein the feature selection algorithm is adapted to identify pixels or voxels as the key features, and is further adapted to calculate a corner quality measure at every pixel or voxel in the image data by calculating a covariation matrix of derivatives and computing eigenvalues.

7. The system of claim 6 , wherein the feature selection algorithm is further adapted to sort the pixels or voxels according to their calculated quality measure and the pixels or voxels with the highest calculated quality measure are selected and identified as key features to be used in tracking and correction or stabilization of motion of the image data.

8. A real-time image motion correction or stabilization system for a projectile or munition in flight comprising:
a projectile or munition comprising at least one sensor adapted to acquire image data periodically or substantially continuously during flight of the projectile or munition, and a processor adapted to receive image data from the at least one sensor;
a feature selection algorithm comprised in the processor and adapted to identify at least two key features in the image data based on the image data acquired during flight of the projectile or munition;
a motion vector application algorithm comprised in the processor and adapted to apply vectors of motion corresponding to the at least two key features in the image data, the vectors of motion characterizing movement associated with the at least two key features within the image data;
a motion estimation algorithm comprised in the processor and adapted to estimate motion of the image sensor based on the vectors of motion corresponding to the identified at least two key features in the image data; and
a stabilization algorithm comprised in the processor and adapted to correct or stabilize movement of the image data based at least in part on the vectors of motion and the estimated motion of the image sensor by shifting one or more images or frames of image data based at least in part on the estimated motion,
wherein motion of the image data exhibits an amplitude of 25 degrees or more and a frequency of 0.1 Hz or greater, and the processor and algorithms are adapted to perform the method on image data exhibiting such motion.

9. The system of claim 8 , further comprising at least one actuator adapted to activate and/or deactivate at least one activatable flow effector to guide the projectile or munition toward a target based at least in part on the corrected or stabilized image data.

10. The system of claim 8 , wherein the processor is further adapted to send a command to the at least one sensor to switch focus of the image data from one of the at least two key features to another of the at least two key features while capturing image data.

11. The system of claim 8 , wherein the motion estimation algorithm is adapted to estimate motion of the image sensor by correlating a distance and direction of the movement associated with the at least two key features within the image data based at least in part on the vectors of motion.

12. The system of claim 8 , wherein the at least two key features identified are not the horizon.

13. The system of claim 8 , wherein the feature selection algorithm is adapted to identify pixels or voxels as the key features, and is further adapted to calculate a corner quality measure at every pixel or voxel in the image data by calculating a covariation matrix of derivatives and computing eigenvalues.

14. The system of claim 13 , wherein the feature selection algorithm is further adapted to sort the pixels or voxels according to their calculated quality measure and the pixels or voxels with the highest calculated quality measure are selected and identified as key features to be used in tracking and correction or stabilization of motion of the image data.

15. A real-time image motion correction or stabilization system for a projectile or munition in flight comprising:
a projectile or munition comprising at least one sensor adapted to acquire image data periodically or substantially continuously during flight of the projectile or munition, and a processor adapted to receive image data from the at least one sensor;
a feature selection algorithm comprised in the processor and adapted to identify at least one key feature in the image data acquired during flight of the projectile or munition;
a motion vector application algorithm comprised in the processor and adapted to apply vectors of motion corresponding to the at least one key feature in the image data, the vectors of motion characterizing movement associated with the at least one key feature within the image data;
a motion estimation algorithm comprised in the processor and adapted to estimate motion of the image sensor based on the vectors of motion corresponding to the identified a

Assignees

• Orbital Res Inc

Inventors

• Jankowski Michael
• Russell Douglas E

Classifications

• F42B15/01 Primary

  Arrangements thereon for guidance or control ({steering arrangements F42B10/60}; aircraft flight control B64C; guidance systems other than those installed aboard F41G7/00, F41G9/00; locating by use of radio or other waves G01S; flight control in general G05D1/00; computer aspects G06]) · CPC title

• H04N23/6811

  based on the image signal · CPC title

• H04N23/683 Primary

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

• G06T7/246

  using feature-based methods, e.g. the tracking of corners or segments · CPC title

• F42B10/02

  Stabilising arrangements · CPC title