Device and method for the detection of buried objects

• US 6,838,671 B2
• Filed: 04/12/2002
• Issued: 01/04/2005
• Est. Priority Date: 04/12/2002
• Status: Expired due to Term

• Current Assignee: Northrop Grumman Systems Corporation (Northrop Grumman Corporation)
• Original Assignee: Northrop Grumman Corporation
• Inventors: Compana, Stephen B., Terrill, Conrad W.
• Primary Examiner(s): Hannaher, Constantine
• Assistant Examiner(s): Gabor, Otilia
• Application Number:
  US10/121,291
• Publication Number:
  US 20030193429A1
• Time in Patent Office: 998 Days
• Field of Search: 250/349, 250/392, 250/366, 250/369, 250/367, 250/368, 89/11.3, 89/11.1, 86/50, 376/159, 376/154, 324/326, 324/329, 324/337, 348/155, 348/143, 701/23, 342/179, 342/24, 253/66
• US Class Current: 250/349
• CPC Class Codes: G01S 13/86 Combinations of radar systems with non-radar systems, e.g. sonar, direction finder
• CPC Class Codes: G01V 3/12 operating with electromagnetic waves operating with millimetre waves G01V8/005
• CPC Class Codes: G01V 3/15 specially adapted for use during transport, e.g. by a person, vehicle or boat
• CPC Class Codes: G01V 8/00 Prospecting or detecting by optical means

Abstract

A device and method for detection of buried objects (40) utilizing a down looking infrared array (140) having infrared detectors (170) positioned in a sensor array (30). This sensor array (30) may also contain ground penetrating radar (70) and EMI coils (80). All signals from the ground penetrating radar (70), EMI coils (80) and down looking infrared array (140) may be combined to generate alarms (1100). However, the down looking infrared array (140) may be utilized as a sole means of detecting buried objects (40). This device and method for detecting buried objects (40) utilizing down looking infrared array (140) reduces the cost of construction and maintenance of such a device.

Claims

1. A device for detecting buried objects, comprising:

a sensor array having a plurality of downward looking infrared detectors; and

a processor based system connected to the sensor array to receive and analyze signals received from the downward looking infrared detectors;

wherein the processor based system receives an image from the sensor array, determines a signal-to-noise ratio for each point in the image, and compares the signal-to-noise ratio with a predetermined threshold to create a binary image indicative of a buried object.

2. The device recited in claim 1, wherein the sensor array comprises:

a plurality of EMI coils connected to the processor based system; and

a plurality of ground penetrating radar sensors connected to the processor based system and wherein signals from the EMI coils and the ground penetrating radar sensors are processed.

3. The device recited in claim 2, wherein the processor-based system will combine signals received from the plurality of downward looking infrared detectors, the plurality of EMI coils and the plurality of ground penetrating radar sensors to determine if the buried object is present.

4. The device received in claim 1, wherein a downward looking infrared sensor of the plurality of downward looking infrared detectors comprises:

a lens to concentrate infrared radiation;

an infrared detection behind the lens to detect the infrared radiation;

a preamp connected to the infrared sensor to amplify a signal generated by the infrared sensor; and

a connection line connected to the preamp and the processor-based system.

5. The device recited in claim 4, wherein the plurality of downward looking infrared detectors are arranged in a row when mounted on the sensor array.

6. The device recited in claim 5, wherein the plurality of downward looking infrared detectors are arranged in a plurality of rows when mounted to the sensor array.

7. The device recited in claim 6, wherein the sensor array is mounted to a vehicle or pushcart.

8. The device recited in claim 7, wherein the buried object is a land mine.

9. A device for detecting buried objects, comprising:

a sensor array further comprising;

a plurality of downward looking infrared detectors;

a plurality of EMI coils; and

a plurality of ground penetrating radar sensors;

a processor based system connected to the sensor array to receive and analyze signals received from the plurality of downward looking infrared detectors, the plurality of EMI coils, and the plurality of ground penetrating radar sensors;

wherein the processor based system receives an image from the sensor array, determines a signal-to-noise ratio for each point in the image, compares the signal-to-noise ratio with a predetermined threshold to create a binary image of a detected buried object, dilates and shrinks the binary image to a single point at the center of the detected buried object.

10. The device recited in claim 9, wherein the processor-based system will combine signals received from the plurality of downward looking infrared detectors, the plurality of EMI coils and the plurality of ground penetrating radar sensors to determine if the buried object is present.

11. The device received in claim 9, wherein a downward looking infrared detector of the plurality of downward looking infrared detector comprises:

a lens to concentrate infrared radiation;

an infrared detector behind the lens to detect the infrared radiation;

a preamp connected to the infrared sensor to amplify a signal generated by the infrared detector; and

a connection line connected to the preamp and the processor-based system.

12. The device recited in claim 11, wherein the plurality of downward looking infrared detectors are arranged in a row when mounted to the sensor array.

13. The device recited in claim 12, wherein the plurality of downward looking infrared detectors are arranged in a plurality of rows when mounted to the sensor array.

14. The device recited in claim 13, wherein the sensor array is mounted to a vehicle or pushcart.

15. The device recited in claim 14, wherein the buried object is a land mine.

16. A method of detecting buried objects, comprising:

receiving an image from a plurality of downward looking infrared detectors;

passing the image through a two-dimensional spatial high pass filter;

determining the signal to noise ratio for each point in the image;

comparing the signal to noise ratio to a predetermined threshold;

thereby creating a binary image;

dilating and shrinking the binary image to a single point at the center of each detected object; and

mapping the single point to earth coordinates.

17. The method recited in claim 16, wherein receiving an image from a plurality of downward looking infrared detectors, further comprises:

receiving a plurality of signals from the plurality of downward looking infrared detectors;

receiving a plurality of signals from a plurality of ground penetrating radar sensors; and

receiving a plurality of signals from a plurality of EMI coils.

18. A method recited in claim 17, further comprising:

extracting features from the plurality of signals from the plurality of downward looking infrared detectors;

extracting features from the plurality of signals from the plurality of ground penetrating radar sensors; and

extracting features from the plurality of signals from the plurality of EMI coils.

19. The method recited in claim 18, further comprising:

fusing the extracted features from the plurality of signals from the plurality of downward looking infrared detectors, the extracted features from the plurality of signals from the plurality of ground penetrating radar sensors, and the extracted features from the plurality of signals from the plurality of EMI coils to generate alarms of the presence of a buried object.