Mobile X-ray inspection system for large objects

• US 5,903,623 A
• Filed: 05/04/1998
• Issued: 05/11/1999
• Est. Priority Date: 02/12/1996
• Status: Expired due to Term

• Current Assignee: American Science and Engineering Incorporated (OSI Systems Incorporated)
• Original Assignee: American Science and Engineering Incorporated (OSI Systems Incorporated)
• Inventors: Tybinkowski, Andrew, Swift, Roderick
• Primary Examiner(s): Church, Craig E.
• Application Number:
  US09/072,212
• Time in Patent Office: 372 Days
• Field of Search: 378/57, 378/198
• US Class Current: 378/57
• CPC Class Codes: G01N 2223/419 computed tomograph
• CPC Class Codes: G01N 23/04 and forming images of the material
• CPC Class Codes: G01N 23/046 using tomography, e.g. computed tomography [CT]
• CPC Class Codes: G01N 23/20 by using diffraction of the radiation by the materials, e.g. for investigating crystal structure; by using scattering of the radiation by the materials, e.g. for investigating non-crystalline materials; by using reflection of the radiation by the materials
• CPC Class Codes: G01V 5/22 Active interrogation, i.e. by irradiating objects or goods using external radiation sources, e.g. using gamma rays or cosmic rays
• CPC Class Codes: G01V 5/222 measuring scattered radiation

Abstract

A device for inspecting a cargo container such as a motor vehicle or freight pallet, with penetrating radiation. A source of penetrating radiation is mounted on a moveable bed, thereby allowing a beam of penetrating radiation to sweep the large container. At least one detector is also mounted on the bed, ether on the side of the source or on a boom, so that, as the beam is scanned across the container, the container and any contents of the container are characterized by transmitted or scattered radiation, or both.

Claims

1. A device, for inspecting a large object with penetrating radiation, the device comprising:

(a) a self-propelled vehicle capable of on-road travel;

(b) a source of penetrating radiation, mounted on the vehicle, for providing a beam of penetrating radiation;

(c) a beam stop for absorbing the beam of penetrating radiation after traversal of the object; and

(d) at least one detector coupled to the vehicle, the at least one detector having a signal output

so that the beam is caused to traverse the object in a first direction as the vehicle is moved and the signal output characterizes the object.

2. A device according to claim 1, further including a control mechanism for control of the motion of the vehicle by an on-board operator during traversal by the beam of the object.

3. A device according to claim 1, wherein the source of penetrating radiation includes a source of penetrating radiation having an energy in substantial excess of 200 keV.

4. A device according to claim 1, wherein the source of penetrating radiation is an x-ray source.

5. A device according to claim 4, wherein the x-ray source is an x-ray tube.

6. A device according to claim 1, wherein the source of penetrating radiation includes an x-ray tube operating at a voltage in substantial excess of 200 kV.

7. A device according to claim 1, wherein the at least one detector is a backscatter detector.

8. A device according to claim 1, wherein the at least one detector is a transmission detector for detecting penetrating radiation transmitted through the object.

9. A device according to claim 1, wherein the at least one detector is a side scatter detector.

10. A device according to claim 1, wherein the at least one detector is a forward scatter detector.

11. A device according to claim 1, wherein the beam is a pencil beam scanned repeatedly along a second direction having a vertical component.

12. A device according to claim 1, wherein the at least one detector has a first element and a second element, the first element being movably mounted with respect to the second element, so that in a first position the first element is angularly disposed with respect to the second element and in a second position the first element is substantially coplanar with respect to the second element.

13. A device according to claim 1, wherein the beam of penetrating radiation is a pencil beam scanned repeatedly over an angle of regard, the angle having an orientation with respect to the horizontal, the device further comprising:

a steering arrangement for steering the orientation of the angle of regard with respect to the horizontal.

14. A device according to claim 1, further comprising a boom assembly having a detector region for supporting the at least one detector, the boom assembly movably linked to the vehicle, the boom assembly having a storage position substantially fixed with respect to the vehicle and an operation position transverse to the first direction.

15. A device according to claim 14, wherein the detector region includes a substantially vertical member disposed distally to the object with respect to the source of penetrating radiation.

16. A device according to claim 14, wherein the beam stop is coupled to the detector region of the boom assembly.

17. A device according to claim 14, wherein at least one detector is coupled to the substantially vertical member.

18. A device according to claim 14, wherein a transmission detector is coupled to the substantially vertical member for responding to penetrating radiation transmitted through the object, so as to provide a signal for forming a transmission image of the object.

19. A device, for inspecting a large object with penetrating radiation, the device comprising:

(a) a self-propelled vehicle capable of on-road travel, the vehicle including;

(i) a first drive train for propelling the vehicle for on-road travel; and

(ii) a second drive train, distinct from the first drive train, for propelling the vehicle in a first direction during inspection of the object;

(b) a source of penetrating radiation, mounted on the vehicle, for providing a beam; and

(c) at least one detector coupled to the vehicle, the at least one detector having a signal output

so that the beam is caused to traverse the object as the vehicle is moved and the signal output characterizes the object.

20. A device according to claim 19, wherein the first drive train includes a first source of power and the second drive train includes a second source of power, the second source of power being distinct from the first source of power.

21. A device according to claim 19, wherein the second drive train includes an hydraulic motor.

22. A device according to claim 19, wherein the second drive train includes an electric motor.

23. A device according to claim 19, wherein at least one of the first and the second drive trains includes an hydraulic coupling.

24. A device according to claim 19, further including a switchable gearbox for coupling no more than one of the first and second drive trains to wheels of the vehicle.

25. A device according to claim 19, further including a control mechanism for control of the motion of the vehicle by an on-board operator during traversal by the beam of the object.

26. A device according to claim 19, wherein the source of penetrating radiation includes a source of penetrating radiation having an energy in substantial excess of 200 keV.

27. A device according to claim 19, wherein the source of penetrating radiation is an x-ray source.

28. A device according to claim 27, wherein the x-ray source is an x-ray tube.

29. A device according to claim 19, wherein the source of penetrating radiation includes an x-ray tube operating at a voltage in substantial excess of 200 kV.

30. A device according to claim 19, wherein the at least one detector is a backscatter detector.

31. A device according to claim 19, wherein the at least one detector is a transmission detector.

32. A device according to claim 19, wherein the at least one detector is a side scatter detector.

33. A device according to claim 19, wherein the at least one detector is a forward scatter detector.

34. A device according to claim 19, wherein the beam is a pencil beam scanned repeatedly along a second direction having a vertical component.

35. A device according to claim 19, wherein the at least one detector has a first element and a second element, the first element being movably mounted with respect to the second element, so that in a first position the first element is angularly disposed with respect to the lower element and in a second position the first element is substantially coplanar with respect to the second element.

36. A device according to claim 19, wherein the source of penetrating radiation includes a source of a pencil beam of penetrating radiation that is scanned repeatedly over an angle of regard, the angle having an orientation with respect to the horizontal, the device further comprising:

a steering arrangement for steering the orientation of the angle of regard with respect to the horizontal.

37. A device according to claim 19, further comprising a boom assembly having a detector region for supporting the at least one detector, the boom assembly movably linked to the vehicle, the boom assembly having a storage position substantially fixed with respect to the vehicle and an operation position transverse to the first direction.

38. A device according to claim 37, wherein the detector region includes a substantially vertical member disposed distally to the object with respect to the source of penetrating radiation.

39. A device according to claim 37, further comprising a beam stop for absorbing penetrating radiation after traversal of the object, the beam stop coupled to the boom assembly.

40. A device according to claim 38, wherein the at least one detector is coupled to the substantially vertical member.

41. A device according to claim 38, wherein a transmission detector is coupled to the substantially vertical member for responding to penetrating radiation transmitted through the object, so as to provide a signal for forming a transmission image of the object.

42. A method, for producing an X-ray image of a large object, the method comprising:

(a) providing a device having;

(1) a self-propelled vehicle capable of on-road travel, the vehicle including;

a source of penetrating radiation, mounted on the vehicle, for providing a beam incident upon the large object;

(2) a beam stop for absorbing the beam of penetrating radiation after traversal of the object; and

(3) at least one detector coupled to the vehicle and having a signal output;

(b) moving the vehicle past the object so as to cause the object to be scanned; and

(c) processing the signal from the signal output of the detector to form an image of the object.

43. A method, for producing an X-ray image of a large object, the method comprising:

(a) providing a device having;

(1) a self-propelled vehicle capable of on-road travel, the vehicle including;

(i) a first drive train for propelling the vehicle for on-road travel; and

(ii) a second drive train, distinct from the first drive train, for propelling the vehicle during inspection of the large object;

(2) a source of penetrating radiation, mounted on the vehicle, for providing a beam incident upon the large object; and

(3) at least one detector coupled to the vehicle and having a signal output;

(b) using the second drive train to move the vehicle past the object so as to cause the beam to scan the object; and

(c) processing the signal from the signal output of the detector to form an image of the object.

44. A system for inspecting an object with penetrating radiation, the system comprising:

(a) a vehicle having wheels and an engine for propelling the vehicle on highways;

(b) a source of penetrating radiation, mounted on the vehicle, for providing a beam;

(c) a motorized scan drive, distinct from the engine, for moving the vehicle in a scan direction; and

(d) at least one detector mounted on the vehicle, the at least one detector having a signal output, so that the beam is caused to traverse the object as the vehicle is moved in the scan direction and the at least one detector provides a signal for characterizing the object.

45. A device, for inspecting a large object with penetrating radiation, the device comprising:

(a) a self-propelled vehicle capable of on-road travel;

(b) a source of penetrating radiation, mounted on the vehicle, for providing a pencil beam of penetrating radiation; and

(c) at least one detector coupled to the vehicle, the at least one detector having a signal output

so that the beam is caused to traverse the object in a first direction as the vehicle is moved and the signal output characterizes the object.

46. A device according to claim 45, further including a control mechanism for control of the motion of the vehicle by an on-board operator during traversal by the pencil beam of the object.

47. A device according to claim 45, wherein the source of penetrating radiation is an x-ray source.

48. A device according to claim 45, wherein the at least one detector is a backscatter detector.

49. A device according to claim 45, wherein the at least one detector is a transmission detector for detecting penetrating radiation transmitted through the object.

50. A device according to claim 45, wherein the at least one detector is a side scatter detector.

51. A device according to claim 45, wherein the at least one detector is a forward scatter detector.

52. A device according to claim 45, wherein the at least one detector has a first element and a second element, the first element being movably mounted with respect to the second element, so that in a first position the first element is angularly disposed with respect to the second element and in a second position the first element is substantially coplanar with respect to the second element.

53. A device according to claim 45, wherein the pencil beam is scanned repeatedly over an angle of regard, the angle having an orientation with respect to the horizontal, the device further comprising:

a steering arrangement for steering the orientation of the angle of regard with respect to the horizontal.

54. A device according to claim 45, further comprising a boom assembly having a detector region for supporting the at least one detector, the boom assembly movably linked to the vehicle, the boom assembly having a storage position substantially fixed with respect to the vehicle and an operation position transverse to the first direction.

55. A device according to claim 54, wherein the detector region includes a substantially vertical member disposed distally to the object with respect to the source of penetrating radiation.

56. A device according to claim 54, wherein at least one detector is coupled to the substantially vertical member.

57. A device according to claim 54, wherein a transmission detector is coupled to the substantially vertical member for responding to penetrating radiation transmitted through the object, so as to provide a signal for forming a transmission image of the object.