Airborne IR fire surveillance system providing firespot geopositioning

• US 6,281,970 B1
• Filed: 03/12/1999
• Issued: 08/28/2001
• Est. Priority Date: 03/12/1998
• Status: Expired due to Term

• Current Assignee: Synergistix LLC
• Original Assignee: Synergistix LLC
• Inventors: Williams, John H., Cooper, Guy F.
• Primary Examiner(s): Buczinski, Stephen C.
• Application Number:
  US09/267,513
• Time in Patent Office: 900 Days
• Field of Search: 356/141.2, 356/141.5, 356/141.4, 702/150, 702/151, 702/152, 702/153, 701/214, 701/223, 250/342, 250/332, 250/334, 250/339.15, 348/144, 244/3.16, 340/578
• US Class Current: 356/141.4
• CPC Class Codes: G01S 19/51 Relative positioning
• CPC Class Codes: G01S 19/53 Determining attitude
• CPC Class Codes: G01S 3/781 Details
• CPC Class Codes: G01S 3/789 using rotating or oscillating beam systems, e.g. using mirrors, prisms
• CPC Class Codes: G01S 5/16 using electromagnetic waves other than radio waves
• CPC Class Codes: G08B 17/005 for forest fires, e.g. detecting fires spread over a large or outdoors area fire fighting forest fires A62C3/02
• CPC Class Codes: G08B 17/12 Actuation by presence of radiation or particles, e.g. of infrared radiation or of ions

Abstract

A system for airborne detection of fires and transmission of fire location and characteristic data to the system ground station. The system includes an airborne pod and an associated ground station. The pod uses a passive infrared (IR) scanning system which employs a rotating and nutating mirror within an air slipstream driven propeller/spinner and is optically coupled to an infrared detector. A computer in the pod receives fire pod GPS position, IR detector fire spot detection pulse or ‘hit’ plus fire spot characteristics, spinner/mirror rotation and nutation angle at the ‘hit’ time and pod platform attitude relative to North-East-down using an on board Inertial Measurement Unit (IMU). The computer then calculates the firespot GPS location, and processes associated firespot characteristic data and downlinks this data to the ground station. Onboard pod video scene cameras also provide operational video that is also downlinked to the ground station.

Claims

1. An aircraft borne system for detecting and locating forest or other fire spots, vehicles, and other IR emitting sources on a terrain, the system comprising:

a means for establishing the position of the aircraft borne system within a reference frame; and

a means for scanning terrain and receiving and measuring IR emitting source photons and determining the position of the IR emitting source relative to the aircraft borne system by determining position vectors from the aircraft borne system to the IR emitting sources which comprises a rotating optics head containing a rotating and nutating mirror contained in a spinner rotationally mounted to a pod which scans the terrain and reflects the IR photons to a photon detector.

2. The aircraft borne system of claim 1, wherein the means for establishing the position of the aircraft borne system within a reference frame, and the means for scanning terrain and receiving and measuring IR emitting source photons and determining the position of the IR emitting source relative to the aircraft borne system are contained in a pod detectably carried by an aircraft.

3. The aircraft borne system of claim 2, wherein the pod is self-contained and needs no power from the aircraft.

4. The aircraft borne system of claim 1, wherein the means for establishing the position of the aircraft borne system within the reference frame comprises a global positioning system.

5. The aircraft borne system of claim 4, wherein the means for establishing the position of the aircraft borne system within the reference frame further comprises an altimeter.

6. The aircraft borne system of claim 5, wherein the altimeter comprises one of a radio altimeter, a corrected precision barometric altimeter, or a GPS that gives vertical position plus a pre-set reference to a reference ground altitude.

7. The aircraft borne system of claim 1, wherein the means for establishing the position of the aircraft borne system within the reference frame further comprises means for determining the system'"'"'s attitude.

8. The aircraft borne system of claim 7, wherein the means for determining the system'"'"'s attitude comprises one of an inertial measurement means, and a radio direction finding means.

9. The aircraft borne system of claim 1, wherein the means for scanning terrain and receiving and measuring IR emitting source photons and determining the position of the IR emitting source relative to the aircraft borne system further comprises an optical angle encoder which reads the rotation angle position of the mirror and a nutation angle reader to determine a directional vector from the aircraft borne system to the IR source.

10. The aircraft borne system of claim 9, wherein the nutation angle reader comprises a laser and a linear array of CCDs.

11. The aircraft borne system of claim 1, wherein the spinner has a propeller and is slipstream driven to rotate the spinner and in turn the optics head.

12. The aircraft borne system of claim 2, further comprising telemetry means for providing communication between the pod and a ground station.

13. The aircraft borne system of claim 12, further comprising a video camera and an IR camera which can be commanded from the ground station to pan and zoom via an onboard camera control unit.

14. The aircraft borne system of claim 1, wherein the means for scanning terrain and receiving and measuring IR emitting source photons and determining the position of the IR emitting source relative to the aircraft borne system further characterizes the IR emitting source target as to intensity and spectrum.

15. The aircraft borne system of claim 2, wherein the means for determining the position of the IR emitting source relative to the pod comprises means to compute the target location using the pod'"'"'s GPS location data, IMU attitude data with respect to local North East Down coordinate frame which also determines true North, and the pod'"'"'s altitude above ground determined by map memory ground elevation data matched to the pod'"'"'s real time GPS coordinates.

16. A system for detecting and locating forest or other fire spots, vehicles, and other IR emitting sources on a terrain, the system comprising:

(a) a self-contained pod that is detachably attachable to an aircraft and does not need power from the aircraft, the pod having

a means for establishing the position of the aircraft borne system within in a reference frame comprising a GPS, an altimeter, and means for determining the pod'"'"'s attitude,

a means for scanning terrain and receiving and measuring IR emitting source photons and determining the position of the IR emitting source relative to the aircraft borne system, comprising a rotating optics head containing a rotating and nutating mirror which scans the terrain and reflects the IR photons to a photon detector, an optical angle encoder which reads the rotation angle position of the mirror, and a nutation angle reader to determine a directional vector from the aircraft borne system to the IR source, and telemetry means; and

(b) a ground station with telemetry means for communication with the telemetry means of the self-contained pod.

17. The system of claim 16, wherein the nutation angle reader comprises a laser and a linear array of CCDs.

18. The system of claim 17, wherein the mirror is contained in a spinner rotationally mounted to a pod.

19. The system of claim 18, further comprising a video camera and an IR camera which can be commanded from the ground station to pan and zoom via an onboard camera control unit.

20. The system of claim 16, wherein the means for scanning terrain and receiving and measuring IR emitting source photons and determining the position of the IR emitting source relative to the aircraft borne system further characterizes the IR emitting source target as to intensity and spectrum.

21. The system of claim 16, the ground station pre-filters incoming telemetry from the pod on a map for ground station operator use, and the ground station includes a transceiver to communicate via a relay transceiver on the pod set to communicate with ground units at or closing in to the IR source.

22. The system of claim 21, wherein the ground station further includes an operator alarm triggered by a pre-set fire intensity and temperature level received from the pod telemetry.

23. The system of claim 21, wherein the ground station further includes archival recording of voice, telemetry/map display, video downlink which can be shared with other users.

24. The system of claim 21, wherein the means for determining the position of the IR emitting source relative to the pod comprises means to compute the target location using the pod'"'"'s GPS location data, IMU attitude data with respect to local North East Down coordinate frame which also determines true North, and the pod'"'"'s altitude above ground determined by map memory ground elevation data matched to the pod'"'"'s real time GPS coordinates.

25. The system of claim 21, further including satellite relay capability on the pod and the ground station for transmission of all downlink video and telemetry plus uplink commands to the pod plus relay voice/data communications from the ground station via the pod to the ground units.

26. The system of claim 16, wherein the means for determining the position of the IR emitting source relative to the pod comprises means to compute the target location using the pod'"'"'s GPS location data, a radio direction finder to determine a vector to a fixed beacon at a ground based location or a geosynchronous satellite and compass to determine true north, and the pod'"'"'s altitude above ground determined by map memory ground elevation data matched to the pod'"'"'s real time GPS coordinates.

27. The system of claim 16, wherein the aircraft is a remotely piloted vehicle.

28. An aircraft borne system for detecting and locating forest or other fire spots, vehicles, and other IR emitting sources on a terrain, the system comprising:

a means for establishing the position of the aircraft borne system within a reference frame;

a means for scanning terrain and receiving and measuring IR emitting source photons and determining the position of the IR emitting source relative to the aircraft borne system by determining position vectors from the aircraft borne system to the IR emitting sources; and

telemetry means for providing communication between the pod and a ground station; and

a video camera and an IR camera which can be commanded from the ground station to pan and zoom via an onboard camera control unit

wherein the means for establishing the position of the aircraft borne system within a reference frame, the means for scanning terrain and receiving and measuring IR emitting source photons and determining the position of the IR emitting source relative to the aircraft borne system, telemetry means, and video camera and IR camera are contained in a pod detectably carried by an aircraft.