Lidar Measurement Device with Target Tracking and Method for Use of Same

• US 20110026008A1
• Filed: 07/28/2009
• Published: 02/03/2011
• Est. Priority Date: 07/28/2009
• Status: Active Grant

• Current Assignee: Applied Concepts Incorporated (Emerson Electric Company)
• Original Assignee: Applied Concepts Incorporated (Emerson Electric Company)
• Inventors: Gammenthaler, Robert S.
• Granted Patent: US 8,125,622 B2
• Time in Patent Office: Days
• US Class Current: 356/28
• CPC Class Codes: G01S 17/42 Simultaneous measurement of distance and other co-ordinates indirect measurement G01S17/46
• CPC Class Codes: G01S 17/58 Velocity or trajectory determination systems; Sense-of-movement determination systems
• CPC Class Codes: G01S 17/86 Combinations of lidar systems with systems other than lidar, radar or sonar, e.g. with direction finders
• CPC Class Codes: G01S 17/88 Lidar systems specially adapted for specific applications
• CPC Class Codes: G08G 1/04 using optical or ultrasonic detectors
• CPC Class Codes: G08G 1/052 with provision for determining speed or overspeed speed measuring in general G01P

Abstract

A Lidar measurement device for vehicular traffic surveillance and method for use of same are disclosed. In one embodiment, video circuitry acquires video of a field of view having a target therein. A steerable laser progressively scans the field of view to identify targets. The steerable laser then progressively, repeatedly scans a sub-field of the field of view containing the target. A processing circuit portion determines target data of the target based upon range and time measurements associated with reflected laser range-finding signals from the scans of the sub-field. The processing circuit then integrates the target data into the video such that the video may displayed with an image of the target and target data, such as a speed measurement, associated therewith.

Claims

1. A Lidar measurement device for traffic surveillance, the Lidar measurement device comprising:

a video circuitry portion for acquiring video of a first field of view having a target therein, the video including an image of the target;

a steerable laser for progressively transmitting laser range-finding signals to a second field of view in a horizontal and vertical step-wise manner and receiving reflected laser range-finding signals from the target, the second field of view having the target therein, the second field of view being a sub-field of the first field;

a processing circuit portion for determining target data of the target based upon range and time measurements associated with the reflected laser range-finding signals, the processing circuit integrating the target data into the video such that the target data is associated with the image of the target; and

a display in communication with the processing circuit portion, the display for displaying the video including the image of the target having the target data associated therewith.

2. The Lidar measurement device for traffic surveillance as recited in claim 1, wherein the target data comprises data selected from the group consisting of speed measurement of the target, range measurement of the target, and heading of the target.

3. The Lidar measurement device for traffic surveillance as recited in claim 1, wherein the processing circuit portion comprises speed-measurement capabilities to determine a speed measurement of the target based upon the range and time measurements associated with the reflected laser range-finding signals.

4. The Lidar measurement device for traffic surveillance as recited in claim 1, wherein the processing circuit portion comprises range-finding capabilities to determine a range measurement of the target based upon the range and time measurements associated with the reflected laser range-finding signals.

5. The Lidar measurement device for traffic surveillance as recited in claim 1, wherein the processing circuit portion comprises direction-sensing capabilities to determine a heading of the target with respect to the Lidar measurement device based upon the range and time measurements associated with the reflected laser range-finding signals.

6. The Lidar measurement device for traffic surveillance as recited in claim 1, further comprising a synchronizer circuit portion for synchronizing the field of view between the video circuitry portion and steerable laser.

7. The Lidar measurement device for traffic surveillance as recited in claim 1, wherein the steerable laser and video circuitry portion comprise identical aspect ratios.

8. The Lidar measurement device for traffic surveillance as recited in claim 1, wherein the processing circuit portion further comprises image stabilization capabilities.

9. The Lidar measurement device for traffic surveillance as recited in claim 1, wherein the Lidar measurement device is operating in a stationary mode.

10. The Lidar measurement device for traffic surveillance as recited in claim 1, wherein the Lidar measurement device is operating in a moving mode.

11. The Lidar measurement device for traffic surveillance as recited in claim 1, wherein the second field of view comprises a sub-field of the first field equal to the first field.

12. A Lidar measurement device for traffic surveillance, the Lidar measurement device comprising:

a video circuitry portion for acquiring video including an image of the target;

a steerable laser for successively progressively transmitting laser range-finding signals to each of an identification space and a target space and receiving reflected laser range-finding signals from the target, the target space of view being a sub-field of the identification space;

a processing circuit portion for identifying a target based upon the reflected laser-range finding signals from the identification space and for determining target data of the target based upon range and time measurements associated with the reflected laser range-finding signals from the target space, the processing circuit integrating the target data into the video such that the target data is associated with the image of the target; and

a display in communication with the processing circuit portion, the display for displaying the video including the image of the target having the target data associated therewith.

13. The Lidar measurement device for traffic surveillance as recited in claim 12, wherein the target data comprises data selected from the group consisting of speed measurement of the target, range measurement of the target, and heading of the target.

14. The Lidar measurement device for traffic surveillance as recited in claim 12, wherein the identification space is scanned by a steerable laser prior to the target space.

15. The Lidar measurement device for traffic surveillance as recited in claim 12, wherein the processing circuit portion further comprises image stabilization capabilities.

16. The Lidar measurement device for traffic surveillance as recited in claim 12, wherein the Lidar measurement device is operating in a stationary mode.

17. The Lidar measurement device for traffic surveillance as recited in claim 12, wherein the Lidar measurement device is operating in a moving mode.

18. The Lidar measurement device for traffic surveillance as recited in claim 12, wherein the second field of view comprises a sub-field of the first field equal to the first field.

19. A method for operating a vehicular traffic surveillance Lidar measurement device, the method comprising:

acquiring video with the Lidar measurement device of a first field of view having a first aspect ratio, the first field of view operably having a target therein, the video including an image of the target;

progressively repeatedly scanning a second field of view having a second aspect ratio with laser range-finding signals from the Lidar measurement device, the second field of view operably having the target therein and being substantially similar to the first field of view, the second aspect ratio being substantially similar to the first aspect ratio;

based on the progressive repeated scanning of the second field of view, identifying the target and associated target space having the target therein;

progressively repeatedly scanning a third filed of view having a second aspect ratio with laser range-finding signals from the Lidar measurement device, the third field of view being the target space, the third field of view being smaller than the second field of view;

during the progressive repeated scanning of the third field of view, receiving reflected laser range-finding signals from the target at the Lidar measurement device;

determining target data of the target based upon range and time measurements associated with the reflected laser range-finding signals; and

integrating the target data into the video such that speed measurement is associated with the image of the target.

20. The method as recited in claim 19, wherein determining target data of the target further comprises determining target data selected from the group consisting of speed measurement of the target, range measurement of the target, and heading of the target.

21. The method as recited in claim 19, wherein the first field of view and the second field of view are identical.

22. The method as recited in claim 19, wherein the first aspect ratio and the second aspect ratio are identical.

23. The method as recited in claim 19, wherein progressively repeatedly scanning the second field of view further comprises horizontal and vertical step size scanning of the second field of view.

24. The method as recited in claim 19, further comprising performing an image stabilization to eliminate visible frame-to-frame jitter in the video.

25. The method as recited in claim 19, further comprising operating the vehicular traffic surveillance Lidar measurement device in a stationary mode.

26. The method as recited in claim 19, further comprising operating the vehicular traffic surveillance Lidar measurement device in a moving mode.

27. A system for operating a vehicular traffic surveillance Lidar measurement device, the method comprising:

means for acquiring video with the Lidar measurement device of a first field of view having a first aspect ratio, the first field of view operably having a target therein, the video including an image of the target;

means for progressively repeatedly scanning a second field of view having a second aspect ratio with laser range-finding signals from the Lidar measurement device, the second field of view operably having the target therein and being substantially similar to the first field of view, the second aspect ratio being substantially similar to the first aspect ratio;

based on the progressive repeated scanning of the second field of view, means for identifying the target and associated target space having the target therein;

means for progressively repeatedly scanning a third field of view having a second aspect ratio with laser range-finding signals from the Lidar measurement device, the third field of view being the target space, the third field of view being smaller than the second field of view;

during the progressive repeated scanning of the third field of view, means for receiving reflected laser range-finding signals from the target at the Lidar measurement device;

means for determining target data of the target based upon range and time measurements associated with the reflected laser range-finding signals; and

means for integrating the target data into the video such that speed measurement is associated with the image of the target.

28. The system as recited in claim 27, wherein determining target data of the target further comprises determining target data selected from the group consisting of speed measurement of the target, range measurement of the target, and heading of the target.