Method and apparatus for high resolution 3D imaging

• US 20060006309A1
• Filed: 07/06/2004
• Published: 01/12/2006
• Est. Priority Date: 07/06/2004
• Status: Active Grant

• Current Assignee: Topcon Positioning Systems Incorporated (Topcon Corporation)
• Original Assignee: Voxis, Inc. (Topcon Corporation)
• Inventors: Chen, William, Dimsdale, Jerry, Lewis, Andrew
• Granted Patent: US 7,697,748 B2
• Time in Patent Office: Days
• US Class Current: 250/206.100
• CPC Class Codes: G01C 11/06 by comparison of two or more pictures of the same area
• CPC Class Codes: G01C 15/002 Active optical surveying means optical plumbing G01C15/105
• CPC Class Codes: G01C 21/1656 with passive imaging devices, e.g. cameras
• CPC Class Codes: G01C 21/183 Compensation of inertial measurements, e.g. for temperature effects
• CPC Class Codes: G01S 17/89 for mapping or imaging

Abstract

A system and method for imaging a three-dimensional scene having one or more objects. The system includes a light source, a detector array, a timing circuit, an inertial guidance system and a processor connected to the timing circuit and the inertial guidance system. The light source generates an optical pulse and projects the optical pulse on an object so that it is reflected as a reflected pulse. The detector array includes a plurality of detectors, wherein the detectors are oriented to receive the reflected pulse. The timing circuit determines when the reflected pulse reached detectors on the detector array. The inertial guidance system measures angular velocity and acceleration. The processor forms a composite image of the three-dimensional scene as a function of camera position and range to objects in the three-dimensional scene.

Claims

1. A method of imaging a three-dimensional scene having one or more objects, comprising:

providing a camera, wherein the camera includes an inertial guidance system and one or more optical detectors;

transmitting a first optical pulse so that a portion of the first optical pulse is reflected from the scene as a first reflected pulse;

detecting arrival of the first reflected pulse at the one or more detectors;

moving the camera relative to objects in the scene;

monitoring angular velocity and acceleration;

determining camera position and trajectory as a function of the angular velocity and acceleration;

transmitting a second optical pulse so that a portion of the second optical pulse is reflected from the scene as a second reflected pulse;

detecting arrival of the second reflected pulse at the one or more detectors; and

forming a composite image of the three-dimensional scene as a function of camera position, camera trajectory and range to objects in the three-dimensional scene.

2. The method of claim 1, wherein the inertial guidance system includes gyroscopes and accelerometers.

3. The method of claim 1, wherein the inertial guidance system includes a global positioning system, gyroscopes and accelerometers.

4. The method of claim 1, wherein forming a composite image of the three-dimensional scene includes simultaneously estimating both a camera trajectory and range image registration as a function of angular velocity, acceleration and the range to objects in the three-dimensional scene.

5. The method of claim 4, wherein the inertial guidance system includes gyroscopes and accelerometers.

6. The method of claim 4, wherein the inertial guidance system includes a global positioning system, gyroscopes and accelerometers.

7. A camera for imaging a three-dimensional scene having one or more objects, comprising:

a light source, wherein the light source generates an optical pulse and projects the optical pulse on an object so that it is reflected as a reflected pulse;

a detector array, wherein the detector array includes a plurality of detectors, wherein the detectors are oriented to receive the reflected pulse;

a timing circuit connected to the detector array, wherein the timing circuit determines when the reflected pulse reached detectors on the detector array;

an inertial guidance system which measures angular velocity and acceleration; and

a processor connected to the timing circuit and the inertial guidance system, wherein the processor forms a composite image of the three-dimensional scene as a function of camera position and range to objects in the three-dimensional scene.

8. The camera according to claim 7, wherein the light source is a laser.

9. The camera according to claim 7, wherein the processor uses information from the inertial guidance system and the timing circuit to simultaneously estimate both a camera trajectory and range image registration.

10. The device according to claim 9, wherein the light source is a laser.

11. The device according to claim 10, wherein the detectors are avalanche photodiodes operating in non-linear Geiger mode.

12. A device for imaging a three-dimensional scene having one or more objects, including:

a pulsed light source;

means for transmitting light toward said objects;

optics for collecting light during the time for light to transit from said pulsed light source, reflect from said objects, be collected and focused by said optics;

a plurality of detectors oriented for receiving the collected light and converting the collected light into an electrical signal; and

timing means, connected to the detectors, for determining a transit time for a pulse to leave the pulsed light source, reflect off the objects and return to one or more of the plurality of deflectors; and

an inertial guidance system which measures angular velocity and acceleration; and

a processor connected to the timing means and the inertial guidance system, wherein the processor forms a composite image of the three-dimensional scene as a function of range to objects in the three-dimensional scene and angular velocity and acceleration of the camera as measured by the inertial guidance system.

13. The device according to claim 12, wherein the light source is a laser.

14. The device according to claim 13, wherein the detectors are avalanche photodiodes operating in non-linear Geiger mode.

15. The device according to claim 12, wherein the processor uses information from the inertial guidance system and the timing means to simultaneously estimate both a camera trajectory and range image registration.

16. The device according to claim 12, wherein the light source is a laser.

17. The device according to claim 13, wherein the detectors are avalanche photodiodes operating in non-linear Geiger mode.

18. A method of imaging a three-dimensional scene having one or more objects, comprising:

providing a camera, wherein the camera includes an inertial guidance system and one or more optical detector arrays;

transmitting a first optical pulse so that a portion of the first optical pulse is reflected from the scene as a first reflected pulse;

detecting arrival of the first reflected pulse at the one or more optical detector arrays;

recording first range information as a function of the arrival of the first reflected pulse;

moving the camera relative to objects in the scene;

recording angular velocity and acceleration information;

transmitting a second optical pulse so that a portion of the second optical pulse is reflected from the scene as a second reflected pulse;

detecting arrival of the second reflected pulse at the one or more optical detector arrays;

recording second range information as a function of the arrival of the second reflected pulse;

estimating camera trajectory and range image registration as a function of the recorded first range information, the recorded second range information, the recorded angular velocity information and the recorded acceleration information; and

forming a composite image of the three-dimensional scene as a function of camera position, camera trajectory, the recorded first range information and the recorded second range information.

19. The method of claim 18, wherein the inertial guidance system includes gyroscopes and accelerometers.

20. The method of claim 18, wherein the inertial guidance system includes a global positioning system, gyroscopes and accelerometers and wherein estimating camera trajectory and range image registration includes estimating camera trajectory and range image registration as a function of a global positioning measurement.

21. A system for imaging a three dimensional scene, comprising:

a focal plane array range imaging optical pulsing camera; and

an inertial guidance system, connected to the camera, wherein the inertial guidance system provides angular velocity and acceleration information corresponding to movements of the camera; and

a processor, connected to the camera and to the inertial guidance system, wherein the processor estimates camera trajectory and range image registration as a function of range information measured by the camera and the angular velocity and acceleration measured by the inertial guidance system and wherein the processor forms a composite image of the three-dimensional scene as a function of camera position, camera trajectory and range information measured by the camera.

22. The system of claim 21, wherein the inertial guidance system includes gyroscopes and accelerometers.

23. The system of claim 21, wherein the inertial guidance system includes a global positioning system, gyroscopes and accelerometers and wherein the processor estimates camera trajectory and range image registration as a function of camera position, camera trajectory, range information measured by the camera and a global positioning measurement measured by the global positioning system.

24. The system of claim 21, wherein the light source is a laser.

25. The system of claim 24, wherein the detectors are avalanche photodiodes operating in non-linear Geiger mode.

26. The system of claim 21, wherein the processor uses information from the inertial guidance system and the camera to simultaneously estimate both a camera trajectory and range image registration.

27. The system of claim 26, wherein the inertial guidance system includes gyroscopes and accelerometers.

28. The system of claim 26, wherein the inertial guidance system includes a global positioning system, gyroscopes and accelerometers and wherein the processor estimates camera trajectory and range image registration as a function of camera position, camera trajectory, range information measured by the camera and a global positioning measurement measured by the global positioning system.

29. The system of claim 26, wherein the inertial guidance system includes a level, a global positioning system, gyroscopes and accelerometers and wherein the processor estimates camera trajectory and range image registration as a function of camera position, camera trajectory, range information measured by the camera and a global positioning measurement measured by the global positioning system.

30. The system of claim 26, wherein the inertial guidance system includes a compass, a level, a global positioning system, gyroscopes and accelerometers and wherein the processor estimates camera trajectory and range image registration as a function of camera position, camera trajectory, range information measured by the camera and a global positioning measurement measured by the global positioning system.

31. A method for collecting range images from a focal plane array imaging optical pulsing camera and placing them on a common coordinate system, the method comprising:

attaching an inertial guidance system to the camera, wherein the inertial guidance system includes a set of gyroscopes and accelerometers;

continuously measuring the set of gyroscopes and accelerometers;

recording first range information at a first camera position;

recording second range information at a second camera position;

determining an estimated camera motion in moving the camera from the first to the second camera position consistent with the first and second range information and the measurements from the set of gyroscopes and accelerometers attached to the camera; and

forming a composite image from the first and second range images;

wherein forming a composite image includes determining alignment of the first and second range images as a function of the estimated camera motion.

32. The method of claim 31, wherein determining an estimated camera motion includes estimating camera trajectory and range image registration as a function of the recorded first range information, the recorded second range information and the measurements from the set of gyroscopes and accelerometers attached to the camera.

33. The method of claim 31, wherein the inertial guidance system further includes a global positioning system and wherein determining an estimated camera motion includes estimating camera trajectory and range image registration as a function of the recorded first range information, the recorded second range information and the measurements from the global positioning system and the set of gyroscopes and accelerometers attached to the camera.