METHOD AND APPARATUS FOR DETECTING AND CLASSIFYING EXPLOSIVES AND CONTROLLED SUBSTANCES

• US 20090147915A1
• Filed: 02/09/2009
• Published: 06/11/2009
• Est. Priority Date: 01/10/2003
• Status: Active Grant

• Current Assignee: Aaron L. Jestice
• Original Assignee: Aaron L. Jestice
• Inventors: Jestice, Aaron L.
• Granted Patent: US 8,358,731 B2
• Time in Patent Office: Days
• US Class Current: 378/64
• CPC Class Codes: G01T 3/00 Measuring neutron radiation G01T5/00 takes precedence
• CPC Class Codes: G01V 5/20 Detecting prohibited goods, e.g. weapons, explosives, hazardous substances, contraband or smuggled objects
• CPC Class Codes: G01V 5/234 Measuring induced radiation, e.g. thermal neutron activation analysis
• CPC Class Codes: Y02E 30/10 Nuclear fusion reactors

Abstract

A system for detecting and classifying small amounts of explosives and other controlled substances while rejecting confounders, including a source/detector array formed of a plurality of sources and a plurality of detectors, a signal processor coupled to the source/detector array for processing data received from the detectors, a classifier coupled to the signal processor for classifying data received from the signal processor according to a plurality of algorithms, a maximal rejection classifier coupled to the classifier; and a declarative decision module coupled to the maximal rejection classifier for rendering an accurate decision regarding the contents of the object is provided. The apparatus includes an enclosure, a shield layer disposed within the enclosure, a cavity disposed within the shield layer, a plurality of neutron sources and a detection array disposed within the cavity, and a transport mechanism for moving objects through the cavity past the sources and detection array. The cavity has one or more turns which preclude a straight line trajectory through the cavity. The shield layer is water-filled to prevent stray radiation from exiting the enclosure. The use of multiple lower power neutron sources and the particular geometry of the enclosure provide a compact, relatively lightweight explosive detection system which is practical for use in airports and other public locations.

Claims

1. A system for detecting explosives and controlled substances in an object, comprising:

a source/detector array comprising a plurality of sources and a plurality of detectors;

a signal processor coupled to the source/detector array for processing data received from the detectors;

a classifier coupled to the signal processor for classifying data received from the signal processor according to a plurality of algorithms;

a maximal rejection classifier coupled to the classifier; and

a declarative decision module coupled to the maximal rejection classifier for rendering a decision regarding the contents of the object.

2. The system of claim 1, further comprising an operator module coupled to the signal processor.

3. The system of claim 2, wherein the operator module is coupled to the declarative decision module.

4. An apparatus for detecting explosives and controlled substances in an object, comprising:

an enclosure;

a shield layer disposed within the enclosure;

a cavity disposed within the shield layer, said cavity comprising one or more turns which preclude a straight line trajectory through the cavity;

a source/detection array disposed within the cavity; and

a transport mechanism for moving objects through the cavity and past the source/detection array.

5. The apparatus of claim 4, wherein the shape of the enclosure is rectangular.

6. The apparatus of claim 5, wherein the dimensions of the enclosure are no more than about 6 meters in length, about 3 meters in width, and about 3 meters in height.

7. The apparatus of claim 4, wherein the shape of the enclosure is selected from the group consisting of rectangular, circular, triangular, and square.

8. The apparatus of claim 4, wherein the shield layer precludes gamma radiation from leaving the enclosure.

9. The apparatus of claim 4, wherein the shield layer comprises water, wherein the water is contained between the enclosure and the cavity.

10. The apparatus of claim 4, wherein the cavity has an opening at each end.

11. The apparatus of claim 4, wherein the ends of the cavity are disposed on opposite sides of the enclosure.

12. The apparatus of claim 4, wherein the cavity further comprises at least three connected segments.

13. The apparatus of claim 12, wherein at least two segments of the cavity are connected to at least another segment at an angle of less than or equal to 90 degrees.

14. The apparatus of claim 12, wherein at least two segments of the cavity are connected to at least another segment at an angle of greater than 90 degrees.

15. The apparatus of claim 4 wherein the shape of the cavity is selected from group consisting of rectangular, circular, triangular, and square.

16. The apparatus of claim 4, wherein the detection array is disposed around the transport mechanism.

17. The apparatus of claim 16, wherein the detection array further comprises a plurality of neutron sources and a plurality of gamma detectors.

18. The apparatus of claim 17, wherein the array is arranged such that an equal number of neutron sources are disposed on at least two sides of the array.

19. The apparatus of claim 17, wherein the array is arranged such that an equal number of gamma detectors are disposed on at least two sides of the array.

20. The apparatus of claim 17, wherein the plurality of neutron sources are low intensity neutron sources.

21. The apparatus of claim 17, wherein the plurality of neutron sources comprises at least 10 neutron sources.

22. The apparatus of claim 17, wherein the plurality of gamma detectors comprises at least 100 gamma detectors.

23-47. -47. (canceled)