Infra-red sensor system for intelligent vehicle highway systems

• US 5,416,711 A
• Filed: 10/18/1993
• Issued: 05/16/1995
• Est. Priority Date: 10/18/1993
• Status: Expired due to Term

• Current Assignee: Grumman Aerospace Corporation (Northrop Grumman Corporation)
• Original Assignee: Grumman Aerospace Corporation (Northrop Grumman Corporation)
• Inventors: Cheung, Lim, Gran, Richard
• Primary Examiner(s): Teska, Kevin J.
• Assistant Examiner(s): MCFADDEN, SUSAN IRIS
• Application Number:
  US08/138,736
• Time in Patent Office: 575 Days
• Field of Search: 364/436, 364/437, 364/438, 364/439, 364/496, 364/497, 364/498, 364/499, 364/550, 364/551.01, 340/933, 340/934, 340/935, 340/936, 340/937, 340/541, 340/905
• US Class Current: 701/117
• CPC Class Codes: G08G 1/04 using optical or ultrasonic detectors

Abstract

An infra-red sensor system for all weather, day and night traffic surveillance of ground based vehicles. The infra-red sensor system comprises system comprises an infra-red, focal plane array detector, signal processors, a communications interface and a central computer. The infra-red, focal plane array detector senses the heat emitted from vehicles passing within the field of view. Information collected from the array detector is input to signal processors which are programmed with tracking algorithms and other application specific algorithms to extract and calculate meaningful traffic data from the infra-red image captured by the array detector. The meaningful data includes the location, speed and acceleration of all vehicles passing within the field of view of the array detector. The information from the signal processors is transmitted to the central computer via the communications interface for further processing and dissemination of information.

Claims

1. A sensor unit comprising:

(a) detector means including an infra-red focal plane array for capturing images of interest;

(b) an electro-optics module having means for focusing said images of interest onto said detector means, means for controlling said detector means, an array of multiple distributed processors, and means for generating a respective one set of video signals from each of at least selected images captured by said detector means and for transmitting each set of signals to at least a plurality of the distributed processors; and

(c) a remote electronics module for conditioning and transforming said video signals from said electro-optics module into a form suitable for digital signal processing, said remote electronics module is connected to said electro-optics module via an interface module contained within said electro-optics module; and

wherein

the sensor unit further includes

i) an array of multiple distributed processors, and

ii) signal circuitry for generating a respective set of signals representing each of at least selected ones of said images, and for transmitting each set of signals to at least a plurality of the distributed processors.

2. The sensor unit according to claim 1, wherein said detector means is a charge-coupled device imager.

3. The sensor unit according to claim 2, wherein said electro-optics module and said remote electronics module are separated a predetermined distance to avoid interference.

4. The sensor unit according to claim 3, wherein said means for focusing images of scenes of interest is a multi-field of view telescopic lens with a built-in miniaturized internal thermoelectric heater/cooler blackbody calibrator that can be slid in or out of the main optics path.

5. The sensor unit according to claim 3, wherein said means for focusing images of scenes of interest is a standard visual band camera lens.

6. An infra-red sensor system for tracking ground based vehicles to determine traffic information, said system comprising:

(a) a sensor unit having at least one array detector for continuously capturing images of a particular traffic corridor, a first portion of said sensor unit being mounted on an overhead support structure such that said at least one array detector has an unobstructed field of view of said traffic corridor;

(b) a signal processor unit connected to said sensor unit for extracting data contained within said images captured by said at least one array detector and calculating traffic information therefrom, including the location, number, weight, axle loading, velocity, acceleration, lateral acceleration, and emission content of said ground based vehicles passing within the field of view of said at least one array detector; and

(c) a local controller unit connected to said signal processor unit for providing and controlling a communications link between said infra-red sensor system and a central control system, said central control system comprising a central computer operable to process information from a multiplicity of infra-red sensor systems;

wherein

at least one said array detector includes an infra-red focal plane array; and

the sensor unit further includes

i) an array of multiple distributed processors, and

ii) signal circuitry for generating a respective set of signals representing each of at least selected ones of said images, and for transmitting each set of signals to at least a plurality of the distributed processors.

7. The infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 6, wherein said sensor unit comprises two array detectors, a first of said two array detectors being a passive infra-red focal plane array and a second of said two array detectors being a visual band charge-coupled device imager.

8. The infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 7, wherein said sensor unit further comprises:

(a) an electro-optics module having means for focusing images of said traffic corridor onto said two array detectors, means for controlling said two array detectors and means for generating video signals from images captured by said two array detectors; and

(b) a remote electronics module for conditioning and transforming said video signals from said electro-optics module into a form suitable for input to said signal processor unit, said remote electronics module is connected to said electro-optics module via an interface module contained within said electro-optics module.

9. The infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 8, wherein said electro-optics module is contained within said first portion of said sensor unit and said remote electronics module being mounted remotely from said electro-optics module to eliminate interference therewith.

10. The infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 9, wherein said signal processor unit comprises:

(a) signal conditioning circuitry for electrically processing said video signals from said remote electronics module and transforming said video signals into a format suitable for digital signal processing;

(b) an array of multiple distributed processors and associated memory, said associated memory comprising a plurality of algorithms which said array of multiple distributed processors utilize to calculate the location, number, weight, axle loading, velocity, acceleration, lateral acceleration, and emission content of said ground based vehicles passing within the field of view of said two array detectors, said array of multiple distributed processors receive input from signal conditioning circuitry;

(c) a local host computer for providing a user interface with said array of multiple distributed processors, and for providing control signals for operating said infra-red sensor system, said local host computer providing a link to said local controller unit, and said local host computer comprises means for controlling local area traffic signals; and

(d) a bi-directional data bus interconnecting and providing a data link between said signal conditioning circuitry, said array of multiple distributed processors and associated memory, and said local host computer.

11. The infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 10, wherein said signal conditioning circuitry comprises window processing circuitry for partitioning said video signals into multiple sub-regions so that each sub-region can be directed to one of several signal processors which comprise said array of multiple distributed processors.

12. The infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 11, wherein said signal processor unit is housed in a single chassis, said chassis comprising a power supply for said signal processor unit.

13. The infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 12, wherein said array of multiple distributed processors and associated memory and said window processing circuitry are expandable.

14. The infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 13, wherein said local controller unit comprises a microprocessor based controller having a data interface and modem for providing a two-way communication link between said infra-red sensor system and said central computer.

15. The infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 14, wherein said data interface is a serial RS-232 compatible data line.

16. A passive, all weather, day/night infra-red sensor system for tracking ground based vehicles to determine traffic information, said system comprising:

(a) a sensor unit having two array detectors for continuously capturing images of a particular traffic corridor, a first portion of said sensor unit being mounted on an overhead support structure such that said two array detectors have an unobstructed field of view of said traffic corridor, a first of said two array detectors being a passive infra-red focal plane array and a second of said two array detectors being a visual band charge-coupled device imager, wherein the sensor unit further includes an array of multiple distributed processors, and signal circuitry for generating a respective set of signals representing each of at least selected ones of said images and for transmitting each set of signals to at least a plurality of the distributed processors;

(b) a signal processor unit connected to said sensor unit for extracting data contained within said images captured by said two array detectors and calculating traffic information therefrom, including the location, number, weight, axle loading, velocity, acceleration, lateral acceleration, and emission content of said ground based vehicles passing within the field of view of said two array detectors; and

(c) a local controller unit connected to said signal processor unit for providing and controlling a communications link between said infra-red sensor system and a central control system, said central control system comprising a multiplicity of infra-red sensor systems.

17. The passive, all weather, day/night infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 16, wherein sensor unit comprises a seismic sensor.

18. The passive, all weather, day/night infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 16, wherein said sensor unit comprises an acoustic sensor.

19. The passive, all weather, day/night infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 16, wherein said passive infra-red focal plane array is a staring mosaic sensor having 480×

640 pixel elements being operable to respond to a broad range of frequencies.

20. The passive, all weather, day/night infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 19, wherein said sensor unit further comprises:

(a) an electro-optics module having means for focusing images of said traffic corridor onto said two array detectors, means for controlling said two array detectors, and means for generating video signals from images captured by said two array detectors; and

(b) a remote electronics module for conditioning and transforming said video signals from said electro-optics module into a form suitable for input to said signal processor unit, said remote electronics module is connected to said electro-optics module via an interface module contained within said electro-optics module.

21. The passive, all weather, day/night infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 20, wherein said electro-optics module is contained within said first portion of said sensor unit and said remote electronics module being mounted remotely from said electro-optics module to eliminate interference therewith.

22. The passive, all weather, day/night infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 21, wherein said signal processor unit comprises:

(a) signal conditioning circuitry for electrically processing said video signals from said remote electronics module and transforming said video signals into a format suitable for digital signal processing;

(b) an array of multiple distributed processors and associated memory, said associated memory comprising a plurality of algorithms which said array of multiple distributed processor utilize to calculate the location, number, weight, axle loading, velocity, acceleration, lateral acceleration, and emission content of said ground based vehicles passing within the field of view of said two array detectors, said array of multiple distributed processors receive input from said signal conditioning circuitry;

(c) a local host computer for providing a user interface with said array of multiple distributed processors, and for providing control signals for operating said infra-red sensor system, said local host computer providing a link to said local controller; and

(d) a bi-directional data bus interconnecting and providing a data link between said signal conditioning circuitry, said array of multiple distributed processors and associated memory, and said local host computer.

23. The passive, all weather, day/night infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 22, wherein said signal conditioning circuitry comprises window processing circuitry for partitioning said video signals into multiple sub-regions so that each sub-region can be directed to one of several signal processors which comprise said array of multiple distributed processors.

24. The passive, all weather, day/night infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 23, wherein said signal processor unit comprises means for processing said multiple sub-regions in the temporal domain and the spatial domain.

25. The passive, all weather, day/night infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 24, wherein said sensor unit comprises spectral filters such that said signal processor unit is operable to process data in the spectral domain.

26. The passive, all weather, day/night infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 25, wherein said signal processor unit is housed in a single chassis, said chassis comprising a power supply for said signal processor unit.

27. The passive, all weather, day/night infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 26, wherein said array of multiple distributed processor and associated memory and said window processing circuitry is expandable.

28. The passive, all weather, day/night infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 27, wherein said local controller unit comprises a microprocessor based controller having a data interface and modem for providing a two-way communication link between said infra-red sensor system and said central computer.

29. The passive, all weather, day/night infra-red sensor system for tracking ground based vehicles to determine traffic information according to claim 28, wherein said data interface is a serial RS-232 compatible data line.

30. A passive infra-red sensor unit comprising:

(a) an electro-optics module having at least one passive infra-red focal plane array detector for continuously capturing images of scenes of interest, means for focusing images of said scenes of interest onto said at least one array detector, means for controlling said at least one array detector, an array of multiple distributed processors, and means for generating a respective one set of video signals from each of at least selected images captured by said at least one array detector and for transmitting each set of signals to at least a plurality of the distributed processors; and

(b) a remote electronics module for conditioning and transforming said video signals from said electro-optics module into a form suitable for digital signal processing, said remote electronics module is connected to said electro-optics module via an interface module contained within said electro-optics module.

31. The passive infra-red sensor unit according to claim 30, wherein said electro-optics module and said remote electronics module are separated a predetermined distance to avoid interference.

32. The passive infra-red sensor unit according to claim 31, wherein said at least one passive infra-red focal array detector is a staring mosaic sensor having 480×

640 pixel elements being operable to respond to a broad range of frequencies.

33. The passive infra-red sensor unit according to claim 32, wherein said means for focusing images of scenes of interest is a multi-field of view telescopic lens with a built-in miniaturized internal thermoelectric heater/cooler blackbody calibrator that can be slid in or out of the main optics path.

34. The passive infra-red sensor unit according to claim 32, wherein said means for focusing images of scenes of interest is a visual bond standard camera lens.

35. A sensor system comprising:

(a) a sensor unit having at least one detector means for continuously capturing images of interest;

(b) a signal processor unit linked to said sensor unit for extracting data contained within said images; and

(c) a local controller unit linked to said signal processor unit for providing and controlling a communications link between said sensor system and a central controller system, said central control system comprising a central computer operable to process, utilize, and disseminate the data from said signal processor;

wherein

at least one said array detector includes an infra-red focal plane array; and

the sensor unit further includes

i) an array of multiple distributed processors, and

ii) signal circuitry for generating a respective set of signals representing each of at least selected ones of said images, and for transmitting each set of signals to at least a plurality of the distributed processors.

36. The sensor system according to claim 35, wherein said at least one detector means is a charged-coupled device imager.

37. The sensor system according to claim 36, wherein said sensor unit further comprises:

(a) an electro-optics module having means for focusing said images of interest onto said charged-coupled device imager, means for controlling said charged-coupled device imager, and means for generating video signals from images captured by said charged-coupled device imager; and

(b) a remote electronics module for conditioning and transforming said video signals from said electro-optics module into a form suitable for input to said signal processor unit, said remote electronics module is linked to said electro-optics module via an interface module.

38. The sensor system according to claim 37, wherein said electro-optics module is contained within a first portion of said sensor unit and said remote electronics module being mounted remotely from said electro-optics module to eliminate interference therewith.

39. The sensor system according to claim 38, wherein said signal processor unit comprises:

(a) signal conditioning circuitry for electrically processing said video signals from said remote electronics module and transforming said video signals into a format suitable for digital signal processing;

(b) an array of multiple distributed processors and associated memory, said array of multiple distributed processors receiving input from said signal conditioning circuitry, and said associated memory comprising a plurality of algorithms which are implemented by said array of multiple distributed processors;

(c) a local host computer for providing a user interface with said array of multiple distributed processors, and for providing control signals for operating said sensor system, said local host computer providing a link to said local controller unit; and

(d) a bi-directional data bus interconnecting and providing a data link between said signal conditioning circuitry, said array of multiple distributed processors and associated memory, and said local host computer.

40. The sensor system according to claim 39, wherein said signal conditioning circuitry comprises window processing circuitry for partitioning said video signals into multiple sub-regions so that each sub-region can be directed to one of several signal processors which comprise said array of multiple distributed processors.

41. The sensor system according to claim 40, wherein said signal processor unit is housed in a single chassis, said chassis comprising a power supply for said signal processor unit.

42. The sensor system according to claim 41, wherein said array of multiple distributed processors and associated memory, and said window processing circuitry are expandable.

43. The sensor system according to claim 42, wherein said local controller unit comprises a microprocessor based controller having a data interface and modem for providing a two-way communication link between said sensor system and said central computer.

44. The sensor system according to claim 43, wherein said data interface is a serial RS-232 compatible data line.