System and method for traffic monitoring, speed determination, and traffic light violation detection and recording

• US 7,616,293 B2
• Filed: 04/29/2005
• Issued: 11/10/2009
• Est. Priority Date: 04/29/2004
• Status: Expired due to Fees

• Current Assignee: Optotraffic, LLC
• Original Assignee: Sigma Space Corp.
• Inventors: Field, Christopher, Marzouk, Marzouk, Seas, Antonios, Sirota, J. Marcos
• Primary Examiner(s): Tarcza; Thomas H
• Assistant Examiner(s): Ratcliffe; Luke D
• Application Number:
  US11/118,540
• Publication Number:
  US 20050242306A1
• Time in Patent Office: 1,656 Days
• Field of Search: 356/28, 356 301- 315, 356 401- 41, 356 501- 515, 356 6- 22, 356/28.5
• US Class Current: 356/28
• CPC Class Codes: G01V 8/20 using multiple transmitters or receivers
• CPC Class Codes: G08G 1/052 with provision for determining speed or overspeed speed measuring in general G01P

Abstract

A system of lasers and detectors to detect the presence of objects and determine their speed is disclosed. The system comprises of a pair of lasers and a pair of detectors focused through a single lens or a pair of lenses. An electronic board that accompanies the lasers and detectors is used to provide the logic and decision making mechanism. Data collected and processed by the system yields such information as whether an object is present, whether the object is stationary or is moving, and subsequent speed information. The described system is also capable of providing additional information concerning the characteristics of the moving object such as its profile and length, and indication of a traffic violation.

Claims

1. A device for sensing an object on a surface, comprising:

a first laser focused through a single lens on said surface;

a first controller which controls radiation emission from said first laser;

a first detector arranged which receives at least a portion of radiation emitted from said first laser and reflected or scattered back through said single lens and which provides a first signal upon receiving said portion of radiation emitted from said first laser;

a second laser focused through said single lens on the surface;

a second controller which controls radiation emission from said second laser;

a second detector which receives at least a portion of radiation emitted from said second laser and reflected or scattered back through said single lens and which provides a second signal upon receiving said portion of radiation emitted from said second laser;

a processor which analyzes said first signal and said second signal, said processor being operationally attached to said first controller, said second controller, said first detector, and said second detector;

a recording device including a camera which receives an output from said processor and documents information about said object on said surface; and

a traffic signal status detector which obtains a status of a traffic control signal;

wherein, said processor analyzes first signal and said second signal to detect said object on said surface and provides an output indicative of a range to said object if detected on said surface, measure, at least one time delay between said first signal and said second signal, calculates a velocity of said object if detected on said surface using said at least one measured time delay, and obtains said status of said traffic control signal from said traffic signal status detector; and

wherein, if said obtained status of said traffic control signal is such that said object on said surface should stop before a traffic violation occurs said processor triggers said camera and records at least one picture of said object on said surface, calculates an amount of time for said object to travel a predetermined distance on said surface, and triggers said camera to take at least one additional picture of said object on said surface.

2. The device according to claim 1, wherein said first laser and said second laser comprise a laser diode.

3. The device according to claim 1, further comprising:

a mirror with at least one aperture which enables radiation from at least one of said first laser and said second laser to pass therethrough, said mirror being aligned to reflect radiation reflected or scattered back through said lens to at least one of said first detector and said second detector.

4. The device according to claim 3, wherein a dimension of the at least one aperture in said mirror is sized and configured such that only eye-safe radiation levels are allowed to pass therethrough.

5. The device according to claim 1, wherein at least one of said first and said second laser is focused in a narrow rectangular spot on said surface with a long side of said rectangular spot being aligned perpendicular to a travel path of said object on said surface.

22. The device according to claim 1, wherein the device for sensing said object on said surface is arranged as an autonomous transportable device including an integrated electric power source.

6. A system for sensing an object moving along a path and recording information about said object, said system comprising:

a first laser and a second laser focused through a single lens on a surface of said path;

a first controller and a second controller which control radiation emission from said first laser and said second laser, respectively;

a first detector and a second detector which receive at least a portion of radiation emitted from said first laser and said second laser respectively and reflected back through said single lens and which provide a first signal and a second signal respectively upon receiving said portions of radiation emitted from said first laser and said second laser respectively;

a processor which analyzes said first signal and said second signal, said processor being operationally attached to said first control, said second controller, said first detectors and said second detector;

a recording device including a camera which receives an output from said processor and documents information about said object along said path; and

a traffic signal status detector which obtains a status of a traffic control signal;

wherein, said processor analyzes said first signal and said second signal to detect said object along said path and provides an output indicative of a range to said object detected along said path, measure at least one time delay between said first signal and said second signal, calculates a velocity of said object detected along said path using said at least one measured time delay, and obtains said status of said traffic control signal from said traffic signal status detector; and

wherein, if said obtained status of said traffic control signal is such that said object if detected along said, path should stop before a traffic violation occurs said processor triggers said camera and recording at least one picture of said object along said path, calculates an amount of time for said object to travel a predetermined distance along said path, and triggers said camera to at least one additional picture of said object along said path.

7. The system according to claim 6, further comprising:

a mirror with at least one aperture to enable radiation from at least one of said first laser and second laser to pass therethrough, said mirror being aligned to reflect radiation reflected back through said lens to at least one of said first detector and said second detector.

8. The system according to claim 7, wherein the size of the at least one aperture in said mirror is sized and configured such that only Class 1 or 2 radiation levels, as defined by FDA 21 CFR 1040.10 are allowed to pass therethrough.

9. The system according to claim 6, said processor further comprising:

at least one time delay counter which measures a time from radiation transmission by at least one of said first laser and said second laser to radiation detection by at least one of said first detector and said second detector respectively.

10. The system according to claim 9, wherein said processor determines if an object is present on said path.

11. The system according to claim 10, wherein said processor provides output to said recording device to determine a profile of said object.

12. The system according to claim 9, wherein said first laser and said second laser are focused on different points on said surface of said path and wherein said points are separated by a known distance.

13. The detector system according to claim 12, wherein at least one of said first laser and said second laser is focused in narrow rectangular spot on said surface of said path with a long side of said rectangular spot being aligned perpendicular to said path of said object on said surface of said path.

23. The system according to claim 6, wherein, the system for sensing said object on said surface is arranged as an autonomous transportable system including an integrated electric power source.

24. The system according to claim 6, wherein the system, for sensing said object on said surface is arranged as an autonomous transportable system for traffic monitoring, and wherein, said recording device includes a digital recording media collocated on a support structure of said traffic monitoring system.

14. A method of determining speed of an object along a path, comprising:

providing a first laser and a second laser focused respectively through a single lens on a first focus point and a second focus point on a surface of said path;

controlling radiation emission from said first and second lasers;

detecting at least a portion of radiation emitted from said first and second laser and reflected back through said single lens and providing a signal upon receiving said radiation;

processing said signal to detect the presence of an object on said path; and

displaying an output indicating the presence of said object if detected;

detecting said object with said first laser;

detecting said object with said second laser;

measuring a time delay between detecting by said first laser and detecting by said second laser; and

calculating a velocity of said object based on a front of said object by dividing a known distance between said first focus point and said second focus point by said time delay between detecting by said first laser and detecting by said second laser

ceasing detecting said object with said first laser;

ceasing detecting said object with said second laser;

measuring the time delay between ceasing detecting by said first laser and ceasing detesting by said second laser; and

calculating the velocity of said object based on a back of said object by dividing said known distance between said first focus points and said second focus point by said time delay between ceasing detecting by said first laser and ceasing detecting by said second laser;

obtaining an input indicating a status of a traffic control signal;

if the traffic control signal indicates that said object on said surface of said path should stop and said velocity of said object is such that it is unlikely that the object can stop before a violation occurs, triggering an imaging device and recording at least one picture of said object;

calculating an amount of time for said object to travel a predetermined distance; and

taking at least one additional picture of said object;

wherein said signal upon receiving said radiation comprises a time delay.

15. The method according to claim 14, wherein at least one of said first laser and said second laser is focused in narrow rectangular spot on said surface with a long side of said rectangular spot being aligned perpendicular to a travel path of an object on said surface.

16. The method according to claim 14, said providing step further comprising:

providing a mirror with at least one aperture to enable radiation form at least one of said first laser and said second laser to pass therethrough, said mirror being aligned to reflect radiation reflected back through said single lens to at least one of said first detector and said second detector.

17. The method according to claim 14, said processing step further comprising:

calculating a height of the object if the time delay for receiving said radiation is less than an expected time delay if no object is present.

18. The method according to claim 14, further comprising the steps of calculating an acceleration of said object by determining a difference between said velocity calculated based on said front of said object and said velocity calculated based on said back of said object and dividing by a time period between starting detection of said object by said first laser and ceasing detecting of said object by said first laser.

19. The method according to claim 14, further comprising a step of calculating an average velocity of said object along said path.

20. The method according to claim 18, further comprising a step of calculating an average acceleration of said object along said path.

21. The method according to claim 14, wherein the status of the traffic control signal is obtained by a traffic signal status detector using a line of sight observation of said traffic control signal.