Process for the indentification of objects

• US 20070081723A1
• Filed: 10/11/2005
• Published: 04/12/2007
• Est. Priority Date: 10/11/2005
• Status: Active Grant

• Current Assignee: Northrop Grumman Systems Corporation (Northrop Grumman Corporation)
• Original Assignee: Northrop Grumman Corporation
• Inventors: Thai, Bea, Aboutalib, Omar, Ramroth, Richard
• Granted Patent: US 7,627,170 B2
• Time in Patent Office: Days
• US Class Current: 382/170
• CPC Class Codes: G06V 20/64 Three-dimensional objects
• CPC Class Codes: G06V 2201/11 Technique with transformation invariance effect

Abstract

The invention is a process for identifying an unknown object. In detail, the process includes the steps of: 1) compiling data on selected features on a plurality of segments of a plurality of known objects; 2) illuminating the unknown object with a laser radar system; 3) dividing the unknown object into a plurality segments corresponding to each of the segments of the known objects; 4) sequentially measuring selected features of each of the plurality of segments of the unknown object; and 5) comparing the sequentially measuring selected features of each of the plurality of segments of the unknown object to the selected features on the plurality of segments of the plurality of known objects.

Claims

1. A process for identifying an unknown object, the process comprising the steps:

compiling data on selected features of a plurality of segments of a plurality of known objects;

illuminating the unknown object by means of a laser radar system;

dividing the unknown object into a plurality segments corresponding to each of the segments of the known objects;

sequentially measuring selected features of each of the plurality of segments of the unknown object; and

comparing the sequentially measuring selected features of each of the plurality of segments of the unknown object to the selected features on the plurality of segments of the plurality of known objects.

2. The process as set forth in claim 1 wherein in the step of compiling data on selected features on a plurality of segments of a plurality of known objects the plurality of segments of the plurality of known objects are bottom and top segments.

3. The process as set forth in claim 1 wherein in the step of compiling data on selected features on a plurality of segments of a plurality of known objects the plurality of segments of the plurality of known objects are bottom, middle and top segments.

4. The process as set forth in claim 3 wherein the in the step of compiling data on selected features on a plurality of segments of a plurality of known objects includes the step of making piecewise pixel-pair invariant measurements of each of the plurality of segments of the known objects.

5. The process as set forth in claim 1, or 2, or 3, or 4, wherein the step of sequentially measuring selected features of each of the plurality of segments of the unknown object includes the steps of comparing the piecewise pixel-pair invariant measurements of each of the plurality of segments of the unknown object until a match is found.

6. The process as set forth in claim 5 wherein the pixel-pair invariant measurements include the distance between first and second pixels of the pixel-pairs, the angle between the normals, {circumflex over (N)}_P and {circumflex over (N)}_Q, to the to the surface area about the first and second pixels, the normalized distance between the first and second pairs along {circumflex over (N)}_P+{circumflex over (N)}_Q, and the normalized distance between the first and second pairs along {circumflex over (N)}_P*{circumflex over (N)}_Q.

7. The process as set forth in claim 6 wherein the pixel-pair invariants are selected from those having angles between normals to their respective surfaces of between 80 and 100 degrees.

8. The process as set forth in claim 7 wherein the step of dividing the unknown object into a plurality segments corresponding to each of the segments of the known objects includes the step of determining the slope of the ground the object is residing on.

9. The process as set forth in claim 8 wherein the step of making piecewise pixel-pair invariant measurements of each of the plurality of segments of the unknown object is conducted with the source of the laser radar at an angle of between 30 and 60 degrees to the slop of the unknown object.