Moving imager camera for track and range capture

• US 6,693,666 B1
• Filed: 12/11/1997
• Issued: 02/17/2004
• Est. Priority Date: 12/11/1996
• Status: Expired due to Term

• Current Assignee: Vulcan Patents LLC
• Original Assignee: Interval Research Corporation
• Inventors: St. Hilaire, Pierre, Kalayjian, Nicholas R., Baker, Henry H., Woodfill, John I.
• Primary Examiner(s): Garber, Wendy R.
• Assistant Examiner(s): NGUYEN, LUONG TRUNG
• Application Number:
  US08/989,202
• Time in Patent Office: 2,259 Days
• Field of Search: 348/169, 348/208, 348/219, 348/316, 348/347, 348/348, 348/357, 348/97, 348/308, 348/208.4, 348/208.5, 348/208.6, 348/208.7, 348/208.14, 348/219.1, 348/79, 348/240.99, 359/676
• US Class Current: 348/219.1
• CPC Class Codes: G01C 11/02 Picture taking arrangements specially adapted for photogrammetry or photographic surveying, e.g. controlling overlapping of pictures

Abstract

A precision motion platform carrying an imaging device under a large-field-coverage lens enables capture of high resolution imagery over the full field in an instantaneous telephoto mode and wide-angle coverage through temporal integration. The device permits automated tracking and scanning without movement of a camera body or lens. Coupled use of two or more devices enables automated range computation without the need for subsequent epipolar rectification. The imager motion enables sample integration for resolution enhancement. The control methods for imager positioning enable decreasing the blur caused by both the motion of the moving imager or the motion of an object'"'"'s image that the imager is intended to capture.

Claims

1. A moving imager camera comprising:

a first positioning mechanism capable of three-dimensional movement;

a first imaging device having an imaging surface, the first imaging device being mounted upon a surface of the first positioning mechanism such that the first imaging device moves in concert with motion of the surface of the first positioning mechanism;

a first measurement system operable to determine a position of the first imaging device within an external frame of reference defined by three axes X, Y, and Z;

a first lens having a focal surface and a field of coverage, the first lens arranged such that the focal surface coincides with the imaging surface of the first imaging device, the field of coverage of the first lens being larger than the optically sensitive area of the imaging surface; and

a processor configured to perform an automated range computation to determine the distance from the camera to an object within the field of coverage, the automated range computation comprising comparing (1) data associated with a first set of image data generated by the first imaging device while in a first position of the first imaging device within the field of coverage of the first lens with (2) data associated with a second set of image data generated by the first image device while in a second position of the first imaging device within the field of coverage of the first lens;

wherein the position of the first lens relative to the object remains fixed during the generation of the first set of image data and the second set of image data and the automated range computation is based at least in part on parallel epipolar geometry.

2. A moving imager camera as recited in claim 1 further including a computer system for controlling motion of the first positioning mechanism.

3. A moving imager camera as recited in claim 1 wherein the first positioning mechanism includes first and second platforms, the first platform operable to move along the X axis of the external frame of reference, the second platform operable to move along the Y axis, the surface of the first positioning mechanism being arranged such that the surface moves in concert with the first and second platforms.

4. A moving imager camera as recited in claim 3 wherein the first positioning mechanism further includes a third platform operable to move along the Z axis of the external frame of reference and the surface of the first positioning mechanism is an upper surface of the third platform.

5. A moving imager camera as recited in claim 3 wherein the first positioning mechanism further includes at least one actuator for actuating one of the first and second platforms.

6. A moving imager camera as recited in claim 5 further including a control system for controlling the operation of the at least one actuator.

7. A moving imager camera as recited in claim 6 wherein the at last one actuator is a stepper motor.

8. A moving imager camera as recited in claim 7 wherein the control system is a differential control system capable of microstepping the stepper motor.

9. A moving imager camera as recited in claim 6 wherein the at least one actuator is a servo motor.

10. A moving imager camera as recited in claim 1 wherein the imaging device is a digital imaging device.

11. A moving imager camera as recited in claim 10 wherein the digital imaging device includes a photosensitive integrated circuit, the photosensitive integrated circuit having an array of photosensitive elements that is the imaging surface of the imaging device.

12. A moving imager camera as recited in claim 11 wherein the photosensitive integrated circuit is operable to process signals generated at the array of photosensitive elements.

13. A moving imager camera as recited in claim 10 wherein the imaging surface of the first imaging device is an array of imaging pixels, the resolution of the array being at least 512 pixels by 512 pixels.

14. A moving imager camera as recited in claim 1 wherein the first measurement system includes an interferometer system operable to determine the position of the first imaging device in the focal plane.

15. A moving imager camera as recited in claim 1 wherein the first measurement system is a sonar based ranging system operable to determine the position of the first imaging device in the focal plane.

16. A moving imager camera as recited in claim 1 wherein the first lens is a lens designed for a 35 millimeter camera.

17. A moving imager camera as recited in claim 1 wherein the first lens is a lens designed for an advanced photo system (APS) camera.

18. A moving imager camera as recited in claim 1 further comprising a computer controlled focusing mechanism.

19. A moving imager camera as recited in claim 18 wherein the computer controlled focusing mechanism is a lens focusing mechanism.

20. A moving imager camera as recited in claim 18 wherein the computer controlled focusing mechanism is a back focusing mechanism.

21. A moving imager camera as recited in claim 18 wherein the computer controlled focusing mechanism uses stereo-computed range to determine focusing distance.

22. A moving imager camera as recited in claim 1 further comprising a computer controlled zoom mechanism providing adaptive selection of the effective field of view.