System and method for the measurement of full relative position and orientation of objects

• US 7,193,556 B1
• Filed: 02/02/2004
• Issued: 03/20/2007
• Est. Priority Date: 09/11/2002
• Status: Expired due to Fees

• Current Assignee: U.S. Government
• Original Assignee: The United States Of America As Represented By The Secretary Of The Army
• Inventors: Rastegar, Jahangir S., Pereira, Carlos M.
• Primary Examiner(s): Gregory; Bernarr E.
• Application Number:
  US10/708,008
• Time in Patent Office: 1,142 Days
• Field of Search: 244 31- 33, 342/59, 342 61- 64, 342/118, 342134-147, 342/175, 342188-197, 342450-465, 342174-158, 342352-367, 89/11.1, 89/65, 343705-718, 343772-786
• US Class Current: 342/62
• CPC Class Codes: F41G 7/34 based on predetermined target position data
• CPC Class Codes: F42B 15/01 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 Class Codes: G01S 5/0247 Determining attitude
• CPC Class Codes: G01S 5/14 Determining absolute distances from a plurality of spaced points of known location
• CPC Class Codes: G01S 7/024 using polarisation effects in waveguides H01P1/165; for aerials H01Q, e.g. H01Q15/22, H01Q15/24, H01Q19/195

Abstract

A system for measuring a position and orientation of an object in flight relative to a reference coordinate system is provided. The system including: three or more illuminating sources, each disposed in a predefined position, the three or more illuminating sources together emitting a plurality of distinct polarized radio frequency signals to provide temporally synchronized, pulsed radio frequency signals that illuminate the object; one or more waveguide cavities disposed on the object for receiving the plurality of distinct polarized radio frequency signals from each of the three or more illuminating sources in flight; and a processor for measuring a time for the plurality of distinct polarized radio frequency signals to propagate from each of the three or more illuminating sources to the one or more waveguide cavities and the level of signal received at the waveguide cavities and to determine a position of the object relative to the three or more illuminating sources based on the measured times and the orientation of the object relative to the reference coordinate system based on the measure levels of received signals.

Claims

1. A system for measuring a position of an object in flight relative to a reference location, the system comprising:

three or more illuminating sources, each disposed in a predefined position, the three or more illuminating sources together emitting a plurality of distinct polarized radio frequency signals to provide temporally synchronized, pulsed radio frequency signals that illuminate the object;

one or more sensors disposed on the object for receiving the plurality of distinct polarized radio frequency signals from each of the three or more illuminating sources in flight; and

a processor for measuring a time for the plurality of distinct polarized radio frequency signals to propagate from each of the three or more illuminating sources to the one or more sensors and to determine a position of the object relative to the three or more illuminating sources based on the measured times.

2. The system of claim 1, wherein the receiver further calculates the distance of the object from the a reference point located at a known position relative to the three or more illuminating sources by determining an intersection point of spheres having the illuminating sources as centers, and the travel distances as radii, and by setting the distance of the intersection point of the spheres as the distance traveled by the object in flight relative to the reference location.

3. The system of claim 1, wherein the one or more sensors comprises three or more sensors each comprising a waveguide cavity, the processor measuring an angular orientation of the waveguide cavities relative to at least one of the three or more illuminating sources based on a level of the signal received at the waveguide cavities in flight.

4. The system of claim 3, wherein each of the three or more sensors are disposed on a surface which is not parallel to the other of the three or more sensors.

5. The system of claim 1, wherein the object comprises a munition.

6. The system of claim 5, wherein the reference location comprises a gun emplacement for firing the munition.

7. The system of claim 1, wherein the one or more sensors are embedded within the object.

8. A method for measuring a position of an object in flight relative to a reference location, the method comprising:

disposing three or more illuminating sources in predefined positions;

emitting a plurality of distinct polarized radio frequency signals from the three or more illuminating sources to provide temporally synchronized, pulsed radio frequency signals that illuminate the object;

disposing one or more sensors on the object for receiving the plurality of distinct polarized radio frequency signals from each of the three or more illuminating sources in flight;

measuring a time for the plurality of distinct polarized radio frequency signals to propagate from each of the three or more illuminating sources to the one or more sensors; and

determining a position of the object relative to the three or more illuminating sources based on the measured times.

9. The method of claim 8, wherein the determining comprises calculating the distance of the object by determining an intersection point of spheres having the illuminating sources as centers, and the travel distances as radii, and by setting the distance of the intersection point of the spheres to a reference location as the distance traveled by the object in flight relative to the reference location.

10. The method of claim 8, wherein the one or more sensors comprises three or more waveguide cavities and the method further comprises:

measuring a level of the signal received at each of the waveguide cavities from any one of the three or more illuminating sources; and

determining an angular orientation of the object based on the measured levels of the signal received at the waveguide cavities in flight.

11. The method of claim 10, wherein each of the three or more sensors are disposed on a surface which is not parallel to the other of the three or more sensors.

12. The method of claim 8, wherein the object comprises a munition.

13. The method of claim 12, wherein the reference location comprises a gun emplacement for firing the munition.

14. The method of claim 8, wherein the one or more sensors are embedded within the object.

15. A munition comprising:

a casing having a nose and tail;

two or more fins disposed on the tail; and

at least a first of three or more sensors disposed on the casing and others on one or more fins, wherein the at least first of the sensors are embedded in the casing and one or more fins and receive a plurality of distinct polarized radio frequency signals from one or more illuminating sources for determining at least one of a position and orientation of the object relative to a reference location, and

at least one fin having a first sensor embedded in a longitudinal surface and a second sensor embedded in a radial surface.

16. A system for measuring an orientation of an object in flight relative to a reference coordinate system, the system comprising:

an illuminating source disposed in a predefined position, the illuminating source emitting a distinct polarized radio frequency signal to illuminate the object;

three or more waveguide cavities disposed on the object for receiving the distinct polarized radio frequency signal from the illuminating source in flight; and

a processor for measuring a level of signal received by each of the three or more the waveguide cavities from the illuminating source and to determine an orientation of the object relative to the illuminating source based on the levels of measured signals.

17. The system of claim 16, wherein the object is a munition and the illuminating source is located at a gun emplacement for firing the munition.

18. A method for measuring an orientation of an object in flight relative to a reference coordinate system, the method comprising:

disposing an illuminating source in a predefined position;

emitting a distinct polarized radio frequency signal from the illuminating source to illuminate the object;

disposing three or more waveguide cavities on the object for receiving the distinct polarized radio frequency signal from the illuminating source in flight;

measuring a level of signal received by each of the three or more waveguide cavities; and

determining an orientation of the object relative to the illuminating source based on the measured level of received signals.