Rotating carriage assembly for use in scanning cargo conveyances transported by a crane

• US 20080084963A1
• Filed: 09/24/2007
• Published: 04/10/2008
• Est. Priority Date: 01/31/2003
• Status: Active Grant

• Current Assignee: Varex Imaging Corporation
• Original Assignee: Varian Medical Systems Incorporated (Siemens AG)
• Inventors: Clayton, James, Bjorkholm, Paul
• Granted Patent: US 7,783,003 B2
• Time in Patent Office: Days
• US Class Current: 378/57
• CPC Class Codes: G01N 23/04 and forming images of the material
• CPC Class Codes: G01V 5/226 using tomography
• CPC Class Codes: G21K 5/10 with provision for relative movement of beam source and object to be irradiated

Abstract

In one example, a radiation scanning system and method rotates a cargo conveyance after removal from a ship for proper orientation with respect to a scanning source and detector, for scanning. A movable carriage may be provided on a crane system, to rotate the cargo conveyance. A rotating flywheel on the carriage rotates in a direction opposite the direction of rotation of the cargo conveyance, to counterbalance angular momentum generated by the rotating conveyance, to avoid or minimize twisting of the carriage. Feedback is provided to control the rotation of the flywheel. Once the cargo conveyance is in the predetermined position, the conveyance is moved between the radiation source and detector for scanning by a vertically extending radiation beam.

Claims

1. A radiation scanning system for scanning an object, comprising:

a crane system to move the object from a first location to a second location;

a radiation source proximate to the crane system; and

a radiation detector proximate to the crane system, the radiation detector positioned to receive radiation interacting with an object;

wherein the source and detector are positioned such that an object may be moved between the source and the detector by the crane system;

the radiation scanning system further comprising;

a carriage to be coupled to the crane system to engage the object and to move the object from the first location to the second location;

wherein the carriage is configured to rotate the object.

2. The radiation scanning system of claim 1, wherein:

the carriage is configured to rotate the object from a first orientation to a second orientation, prior to moving the object between the radiation source and radiation detector.

3. The radiation scanning system of claim 2, further comprising:

a rotatable member coupled to the carriage;

wherein;

the carriage is configured to rotate the object in a first direction; and

the rotatable member is rotatable in a second direction opposite to the first direction.

4. The radiation scanning system of claim 3, further comprising:

a feedback system to control rotation of the rotatable member based, at least in part, on a weight of a cargo conveyance engaged by the carriage.

5. The radiation scanning system of claim 4, wherein the feedback system comprises:

a controller to determine a speed of rotation of the rotatable member to counteract, at least in part, the angular momentum generated by rotation of the second member; and

a motor coupled to the controller and to the rotatable member, to rotate the rotatable member at the speed determined by the controller.

6. The radiation scanning system of claim 5, further comprising:

a sensor coupled to the carriage to determine a weight of the object.

7. The radiation scanning system of claim 1, wherein:

the source and the detector are separated by a space; and

the object is movable horizontally by the carriage through the space.

8. The radiation scanning system of claim 7, wherein:

the source is adapted to emit a vertically diverging beam towards the detector.

9. The radiation scanning system of claim 1, wherein:

at least one of the source and the detector are supported by the ground.

10. The radiation scanning system of claim 9, wherein:

the source and the detector are within a profile defined by the crane system.

11. The radiation scanning system of claim 1, wherein:

the source and the detector are supported by the crane system.

12. The radiation scanning system of claim 1, wherein:

the carriage is configured to rotate the object without twisting that would interfere with scanning.

13. A method for radiation scanning an object, comprising:

suspending an object in the air;

rotating the object to a predetermined orientation with respect to a radiation source, prior to scanning the object;

scanning the object by a radiation source while in the predetermined orientation; and

detecting radiation after interacting with the object.

14. The method of claim 13, further comprising:

moving the object between the source and the detector, during scanning.

15. The method of claim 13, comprising rotating the object to the predetermined orientation without twisting that would interfere with scanning.

16. The method of claim 13, further comprising:

counterbalancing, at least in part, angular momentum generated by rotating the object.

17. The method of claim 16, comprising:

rotating the object in a first direction; and

counterbalancing the angular momentum by rotating a member coupled to the object in a second direction opposite the first direction.

18. The method of claim 17, comprising:

rotating the object at a first speed;

determining a weight associated with the object; and

rotating the rotatable member at a second speed based, at least in part, on the weight and the first speed of the object.

19. The method of claim 13, comprising:

suspending the object by lifting the object off of a ship.

20. The method of claim 19, further comprising:

rotating the object to a second predetermined orientation after detecting radiation; and

lowering the object onto a truck while in the second orientation.

21. The method of claim 13, comprising:

suspending the object by lifting the object off of a truck.

22. The method of claim 21, further comprising:

rotating the object to a second predetermined orientation after detecting radiation; and

lowering the object onto a ship while in the second orientation.

23. A radiation scanning system for scanning an object, comprising:

a crane system to move the object from a first location to a second location;

a radiation source proximate to the crane system; and

a radiation detector proximate to the crane system, the radiation detector positioned to receive radiation interacting with an object;

wherein the source and detector are positioned such that an object may be moved between the source and the detector by the crane system;

the radiation scanning system further comprising;

a carriage to be coupled to the crane system to engage the object and to move the object from the first location to the second location; and

a rotatable member coupled to the carriage;

wherein;

the carriage is configured to rotate the object in a first direction from a first orientation to a second orientation; and

the rotatable member is rotatable in a second direction opposite to the first direction.

24. A method for radiation scanning an object, comprising:

suspending an object in the air;

rotating the object to a predetermined orientation with respect to a radiation source, prior to scanning the object;

counterbalancing, at least in part, angular momentum generated by rotating the object;

scanning the object by a radiation source while in the predetermined orientation; and

detecting radiation after interacting with the object.

25. A crane to move an object, the crane comprising:

a support;

a boom arm supported by the support;

a carriage movably supported by the boom arm to engage an object and to move the object from a first location to a second location;

a rotatable member coupled to the carriage;

wherein the carriage is configured to rotate the object in a first direction; and

the rotatable member is configured to rotate in a second direction opposite to the first direction.