Vehicle lamp control

• US 6,611,610 B1
• Filed: 03/20/2000
• Issued: 08/26/2003
• Est. Priority Date: 04/02/1997
• Status: Expired due to Term

• Current Assignee: Gentex Corporation
• Original Assignee: Gentex Corporation
• Inventors: Roberts, John K., Tonar, William L., Stam, Joseph S., Bechtel, Jon H., Poe, G. Bruce, Reese, Spencer D.
• Primary Examiner(s): Patel, Jayanti K.
• Assistant Examiner(s): Tabatabai, Abolfazl
• Application Number:
  US09/528,389
• Time in Patent Office: 1,254 Days
• Field of Search: 382/104, 250/208.1, 250/208, 250/214, 250/226, 250/573, 250/574, 340/930, 340/933
• US Class Current: 382/104
• CPC Class Codes: B60Q 1/085 due to special conditions, e.g. adverse weather, type of road, badly illuminated road signs or potential dangers B60Q1/10, B60Q1/12, B60Q1/1423 take precedence
• CPC Class Codes: B60Q 1/143 combined with another condition, e.g. using vehicle recognition from camera images or activation of wipers
• CPC Class Codes: B60Q 1/18 being additional front lights bracket mounted headlights B60Q1/0483
• CPC Class Codes: B60Q 2300/054 Variable non-standard intensity, i.e. emission of various beam intensities different from standard intensities, e.g. continuous or stepped transitions of intensity
• CPC Class Codes: B60Q 2300/056 Special anti-blinding beams, e.g. a standard beam is chopped or moved in order not to blind
• CPC Class Codes: B60Q 2300/112 Vehicle speed
• CPC Class Codes: B60Q 2300/114 Vehicle acceleration or deceleration
• CPC Class Codes: B60Q 2300/116 Vehicle at a stop
• CPC Class Codes: B60Q 2300/122 Steering angle
• CPC Class Codes: B60Q 2300/134 Yaw
• CPC Class Codes: B60Q 2300/142 Turn signal actuation
• CPC Class Codes: B60Q 2300/144 Rearward ratio actuation
• CPC Class Codes: B60Q 2300/21 Manual control
• CPC Class Codes: B60Q 2300/312 Adverse weather
• CPC Class Codes: B60Q 2300/314 Ambient light
• CPC Class Codes: B60Q 2300/32 Road surface or travel path
• CPC Class Codes: B60Q 2300/322 Road curvature
• CPC Class Codes: B60Q 2300/332 on city roads
• CPC Class Codes: B60Q 2300/3321 Detection of streetlights
• CPC Class Codes: B60Q 2300/333 on suburban or country roads
• CPC Class Codes: B60Q 2300/334 : on motorways
• CPC Class Codes: B60Q 2300/337 : Tunnels or bridges
• CPC Class Codes: B60Q 2300/41 : preceding vehicle
• CPC Class Codes: B60Q 2300/42 : oncoming vehicle
• CPC Class Codes: B60Q 2400/30 : Daytime running lights [DRL], e.g. circuits or arrangements therefor
• CPC Class Codes: G06V 10/141 : Control of illumination
• CPC Class Codes: G06V 20/10 : Terrestrial scenes scenes under surveillance with static cameras G06V20/52; scenes perceived from the exterior of a vehicle G06V20/56; scenes perceived from the interior of a vehicle G06V20/59
• CPC Class Codes: G06V 20/584 : of vehicle lights or traffic lights

Abstract

A system and method of automatically controlling vehicle headlamps includes an image sensor and a controller to generate headlamp control signals.

Claims

1. A method of automatically controlling vehicle headlamps in a system comprising an image sensor generating a plurality of pixel levels from a scene being imaged and a controller to generate headlamp control signals, the method comprising the steps of:

receiving pixel levels from the image sensor;

identifying at least one group of contiguous pixels that is associated with a light source;

analyzing the associated group of pixels to determine at least one of the following properties of the pixel group;

the number of pixels in the group, the width, the height, a total gray scale value, and a centroid location; and

selectively generating a headlamp control signal in accordance with the at least one property determined in the analysis.

2. The method of claim 1, wherein the step of identifying a group of pixels associated with a single light source identifies a plurality of pixels meeting a pixel criteria.

3. The method of claim 2, wherein the step of identifying a group of pixels identifies a contiguous group of pixels meeting a pixel criteria.

4. The method of claim 2, wherein the step of identifying a plurality of pixels meeting a pixel criteria identifies individual pixels having levels above a pixel threshold level.

5. The method of claim 1, wherein the step of analyzing determines the size of at least one group of pixels.

6. The method of claim 5, wherein the at least one property is whether the light source size is greater than a threshold size.

7. A method of automatically controlling vehicle headlamps in a system comprising an image sensor generating a plurality of pixel levels from a scene being imaged and a controller to generate headlamp control signals, the method comprising the steps of:

receiving pixel levels from the image sensor;

identifying at least one group of pixels that is associated with a light source;

analyzing the associated pixels to identify the centroid of at least one group of pixels; and

selectively generating a headlamp control signal as a function of the identified centroid.

8. A method of automatically controlling vehicle headlamps in a system comprising an image sensor generating a plurality of pixel levels from a scene being imaged and a controller to generate headlamp control signals, the method comprising the steps of:

receiving pixel levels from the image sensor;

identifying at least one group of pixels that is associated with a light source; and

analyzing the associated pixels to determine the average level of the pixel levels,

wherein the headlights are not controlled responsive to a group of pixels that is greater than the threshold size if the average pixel level in that group of pixels is less than an average pixel level threshold.

9. A method of automatically controlling vehicle headlamps in a system comprising an image sensor generating a plurality of pixel levels from a scene being imaged and a controller to generate headlamp control signals, the method comprising the steps of:

receiving pixel levels from the image sensor;

identifying at least one group of pixels that is associated with a light source;

analyzing the associated pixels to determine the total pixel level for at least one group of pixels; and

selectively generating a headlamp control signal in accordance with the results of the analysis.

10. The method of claim 9, where the total pixel level is the sum of the grey scale values for all of the pixels in a group of pixels.

11. The method of claim 9, where the step of analyzing the associated pixels includes determining whether the total pixel level exceeds a threshold total pixel level.

12. The method of claim 10, further including a threshold total pixel level for the headlights and a threshold total pixel level for tail lights.

13. A method of automatically controlling vehicle headlamps in a system comprising an image sensor generating a plurality of pixel levels from a scene being imaged and a controller to generate headlamp control signals, the method comprising the steps of:

receiving pixel levels from the image sensor;

identifying at least one group of pixels that is associated with a light source;

analyzing the associated pixels to determine the average pixel level for at least one group of pixels; and

selectively generating a headlamp control signal in accordance with the results of the analysis.

14. The method of claim 13, wherein the condition is a threshold average pixel level, and the controller ignores certain light sources where the average pixel level for the group of pixels is below the average pixel level.

15. A method of automatically controlling vehicle headlamps in a system comprising an image sensor generating a plurality of pixel levels from a scene being imaged and a controller to generate headlamp control signals, the method comprising the steps of:

receiving pixel levels from the image sensor;

analyzing an image input with red filtering to identify objects of interest;

analyzing an image input without red filtering in those areas where objects were identified in the step of analyzing with red filtering; and

selectively generating a headlamp control signal in accordance with the results of the steps of analyzing.

16. The method of claim 15, further including the step of comparing pixels levels in the image generated with red filtering to pixel levels in the image generated without red filtering for each of the objects of interest.

17. The method of claim 15, wherein the step of analyzing an image input with red filtering includes identifying groups of contiguous pixels meeting a threshold criteria to identify objects.

18. The method of claim 17, wherein the step of analyzing an image input without red filtering includes searching for groups of contiguous pixels in areas corresponding to objects identified in the step of analyzing an image input without red filtering.

20. The method of claim 18, further including controlling one or more fog lights responsive to the ambient light sensor and the image sensor.

19. A method of automatically controlling vehicle beadlamps in a system comprising an image sensor generating a plurality of pixel levels from a scene being imaged and a controller to generate headlamp control signals, the method comprising the steps of:

receiving pixel levels from the image sensor;

receiving an ambient light level; and

analyzing an image input from the image sensor according to the ambient light level to selectively generate a headlamp control signal in accordance with the results of the analysis, wherein daytime running lights are enabled when the ambient light level is above a first threshold, low beam headlamps are enabled when the ambient light level is below the first threshold, and the low beam headlamps and high beam headlamps are enabled when the ambient light level is below a second threshold, and wherein the high beam headlamps are controlled automatically responsive to the pixel levels from the image sensor, the second threshold representing a lower ambient light level than the first threshold.

21. The method of claim 19, wherein the step of controlling includes evaluating the pixels of the image sensor to determine if they meet a fog criteria if the ambient light level measured by the ambient light sensor is within a predetermined range.

22. A method of automatically controlling vehicle headlamps in a system comprising an image sensor generating a plurality of pixel levels from a scene being imaged and a controller to generate headlamp control signals, the method comprising the steps of:

receiving pixel levels from the image sensor;

analyzing the image input from the image sensor to determine the number of AC light source objects in the image; and

selectively generating a headlamp control signal in accordance with the results of the steps of analyzing, and inhibiting operation of the high beams when the number AC light source objects exceeds a threshold.

23. The method as defined in claim 22, wherein the step of analyzing the image to detect objects monitors the frequency of occurrence of objects within a predetermined period.

24. The method as defined in claim 23, wherein the predetermined period is a predetermined number of frames.

25. A method of automatically controlling vehicle headlamps in a system comprising an image sensor generating a plurality of pixel levels from a scene being imaged and a controller to generate headlamp control signals, the method comprising the steps of:

receiving pixel levels from the image sensor;

analyzing the image input from the image sensor to determine the number of objects in the image; and

selectively generating a headlamp control signal in accordance with the results of the steps of analyzing, wherein the vehicle headlamps are not adjusted responsive to detection of an object unless it appears in a threshold number of frames,

wherein the threshold number of frames is a function of the brightness of the objects detected.

26. The method of claim 25, wherein the brighter the object detected, the smaller will be the threshold number of frames.

27. A method of automatically controlling vehicle beadlamps in a system comprising an image sensor generating a plurality of pixel levels from a scene being imaged and a controller to generate headlamp control signals, the method comprising the steps of:

receiving pixel levels from the image sensor;

analyzing the image input from the image sensor to determine the number of objects in the image; and

selectively generating a headlamp control signal in accordance with the results of the steps of analyzing, wherein the vehicle headlamps are not adjusted responsive to detection of an object unless it appears in a threshold number of frames,

wherein the brightness of the headlamps are gradually altered after an object is detected for the threshold number of frames.

28. The method of claim 27, wherein after an object is detected for the threshold number of frames, the high beams may be adjusted responsive to each successive frame in which the object appears.

29. The method of automatically controlling vehicle headlamps in a system comprising an image sensor generating a plurality of pixel levels from a scene being imaged and a controller to generate headlamp control signals, the method comprising the steps of:

receiving pixel levels from the image sensor;

analyzing the image input from the image sensor to determine the number of objects in the image; and

selectively generating a headlamp control signal in accordance with the results of the steps of analyzing, wherein the vehicle headlamps are not adjusted responsive to detection of an object unless it appears in a threshold number of frames,

wherein the headlamp brightness is increased after the image clears for the threshold number of frames.

30. The method of claim 29, wherein the headlamp brightness is dimmed after an object is detected in the image for the threshold number of frames.

31. A method of automatically controlling vehicle headlamps in a system comprising an image sensor generating a plurality of pixel levels from a scene being imaged and a controller to generate headlamp control signals, the method comprising the steps of:

receiving pixel levels from the image sensor;

identifying pixels that are associated with an object;

analyzing the associated pixels and storing information associated with at least one detected object in an object list;

analyzing the objects in the object list to generate a light list; and

selectively generating a headlamp control signal in accordance with an analysis of the light list.

32. The method of claim 31, wherein the stored information includes the brightness of at least one object detected.

33. The method of claim 32, wherein the stored information includes the location of at least one object detected.

34. The method of claim 31, wherein the stored information includes the locations and brightness of the brightest object detected.

35. A method of automatically controlling vehicle headlamps in a system comprising a sensor for sensing light sources forward of the vehicle and a controller to generate headlamp control signals, the method comprising the steps of:

detecting the passage of an oncoming vehicle; and

if, following passage of the oncoming vehicle, the sensor does not sense any light sources and the high beams are OFF, the high beams are controlled to produce a fast return to bright.

36. The method of claim 35, wherein the control of the high beams to produce a fast return to bright includes an expedited fade to bright.

37. The method of claim 35, wherein the control of the high beams to produce a fast return to bright comprises turning the high beams ON without delay.

38. A method of automatically controlling vehicle headlamps in a system comprising a sensor for sensing light sources forward of the vehicle and a controller to generate headlamp control signals, the method comprising the steps of:

detecting the passage of a preceding vehicle; and

if, following passage of the preceding vehicle, the sensor does not sense any light sources and the high beams are OFF, the high beams are controlled to produce a tail light delayed return to bright.

39. The method of claim 38, wherein the tail light delayed return to bright is longer than a return to bright following detection of headlights from an oncoming vehicle.

40. The method of claim 38, wherein the tail light delayed return to bright is variable.

41. The method of claim 38, wherein the tail light return to bright is dependent on the detection of glare light.

42. The method of claim 41, wherein the high beams are turned on when glare is detected.

43. The method of claim 42, wherein if glare is not detected in a maximum threshold time after detecting the cleared image, the high beams are turned ON even if glare has not been detected.

44. A method of automatically calibrating the aim of an image sensor in a controlled vehicle, comprising the steps of:

detecting a distant light of an oncoming vehicle;

detecting a straight road condition; and

generating a new average value from the location of the distant oncoming light averaged with a stored average if the straight road condition is detected, and

storing the new average value as the stored average signal.

45. The method of claim 44, wherein the step of detecting a distant light comprises detecting a faint light near the center of the image sensor.

46. The method of claim 44, further including the step of detecting elevation change of the controlled vehicle.

47. The method of claim 44, wherein the step of detecting a straight road detects the lateral movement of the controlled vehicle over a period of time.

48. The method of claim 47, wherein the period of time is from the time that the distant light is detected until a time period after the distant vehicle and the controlled vehicle have passed.

49. The method of claim 47, wherein lateral movement is detected by determining the lateral movement of the distant headlight.

50. The method of claim 47, wherein lateral movement is detected using a global positioning system.

51. The method of claim 47, wherein lateral movement is detected from a compass.

52. The method of claim 47, wherein lateral movement is detected from operation of the steering system.

53. The method of claim 44, wherein the average value is used to calibrate the aim of the image sensor.

54. The method of claim 44, wherein the average value is used to determine a region of analysis in the image obtained by the image sensor.

55. The method of claim 44, wherein the aim of the image sensor is calibrated only when the vehicle is traveling at a speed falling within a predetermined range of speeds.

58. The method of claim 51, wherein the image analyzed is shifted when the vehicle turn signal is actuated.

59. The method of claim 51, wherein the specified sensitivity is altered by altering thresholds to which the pixel levels are compared during the step of analyzing.

56. A method of automatically controlling vehicle headlamps in a system comprising an image sensor generating a plurality of pixel levels from a scene being imaged and a controller to generate headlamp control signals, the method comprising the steps of:

receiving pixel levels from the image sensor;

analyzing the pixel levels associated with a scene at a specified sensitivity, wherein the specified sensitivity is altered in response to a vehicle turn; and

selectively generating a headlamp control signal in accordance with the results of the analysis.

57. The method of claim 56, wherein the image analyzed is shifted when the vehicle turns.

60. A method of automatically controlling vehicle headlamps in a system comprising an image sensor generating a plurality of pixel levels from a scene being imaged and a controller to generate headlamp control signals, the method comprising the steps of:

receiving pixel levels from the image sensor;

analyzing the pixel levels associated with a scene, wherein the analysis is altered when the vehicle turns; and

selectively generating a headlamp control signal in accordance with the results of the analysis,

wherein the analysis of the image is altered when the vehicle heading as detected from a compass is altered.

61. The method of claim 60, wherein the analysis is altered after actuation of the vehicle brakes following actuation of the vehicle'"'"'s turn signal.

62. A method of automatically controlling vehicle headlamps in a system comprising an image sensor generating a plurality of pixel levels from a scene being imaged and a controller to generate headlamp control signals, the method comprising the steps of:

receiving pixel levels from the image sensor, wherein the pixel levels are acquired and stored while the vehicle headlamps are momentarily deactivated;

analyzing the pixels to detect objects; and

selectively generating a headlamp control signal in accordance with the results of the analysis.

63. The method of claim 62, wherein the vehicle includes semiconductor radiation emitter light source, wherein the light is flashed off for a very short interval.

64. The method of claim 63, wherein the off interval is less than 60 ms.

65. A method of automatically controlling vehicle headlamps in a system comprising an image sensor generating a plurality of pixel levels from a scene being imaged through a windshield, a windshield wiper for clearing the windshield, and a controller to generate headlamp control signals, the method comprising the steps of:

receiving signals indicative of the location of the windshield wiper;

receiving pixel levels from the image sensor when the windshield wiper is not in front of the image sensor;

analyzing the associated pixels to identify objects; and

selectively generating a headlamp control signal in accordance with the results of the analysis.

66. The method of claim 65, further including the step of monitoring the window using an image sensor focused on the window to detect the presence of the windshield wiper in the field of view of the image sensor for detecting objects.

67. The method of claim 65, further including the step of monitoring the windshield wipers to detect their position.

68. A vehicle system, comprising:

an image sensor for detecting lights;

an ambient light sensor;

a glare sensor;

an electrochromic element for controlling the reflectivity of a mirror;

headlights; and

a controller coupled to the image sensor, the ambient light detector, the glare sensor, the electrochromic element, and the headlights, wherein the controller is operable to control the headlights responsive to the image sensor and the ambient light sensor, and the controller being further operable to control the transmittance of the electrochromic element responsive to the ambient light sensor and the glare sensor, and further comprising a rearview mirror assembly adapted for mounting to a vehicle and supporting said electrochromic element, wherein said controller is carried on said rearview mirror assembly.

69. A method of operating an image sensor generating a plurality of pixel levels from a scene being imaged, the method comprising the steps of:

receiving pixel levels from the image sensor;

identifying a bad pixel if a pixel continuously detects light when adjacent pixels do not detect light; and

selectively compensating for the identified pixels.

70. The method of claim 69, wherein the step of identifying a pixel that continuously detects light comprises determining that the pixel detects light over a predetermined number of frames.

71. The method of claim 70, wherein the step of identifying includes detecting when a pixel detects light above a pixel threshold over a predetermined number of frames and adjacent frames do not detect light above a pixel threshold over the predetermined number of frames.

72. The method of claim 69, wherein the step of selectively compensating comprises generating an average of the adjacent pixels and substituting the generated average for the pixel level measurement of the bad pixel.

73. A method of automatically controlling vehicle headlamps in a system comprising an image sensor generating a plurality of pixel levels from a scene being imaged and a controller to generate headlamp control signals, the method comprising the steps of:

receiving pixel levels from the image sensor;

analyzing the image input from the image sensor using different thresholds for different pixels based on their pixel location;

changing the different thresholds for the pixels based on their pixel location as the vehicle changes direction; and

selectively generating a headlamp control signal in accordance with the results of the steps of analyzing.

74. The method of claim 73, wherein the step of analyzing the image includes using a spatial look-up table, the spatial look-up table having different thresholds for different pixels based on their pixel location.

75. The method of claim 74, wherein the step of changing thresholds includes shifting the pixels associated with the values stored in the spatial look-up table as the vehicle changes direction.

76. The method of claim 75, wherein the step of shifting the pixels includes shifting the pixels responsive to operation of the vehicle steering system.

77. The method of claim 75, wherein the step of shifting the pixels includes shifting the pixels responsive to a global positioning system input.

78. The method of claim 75, wherein the step of shifting the pixels includes shifting the pixels responsive to a compass input.

79. The method of claim 73, wherein the high beams are controlled responsive to those pixels from the image sensor exceeding its respective pixel threshold.

80. A method of automatically controlling vehicle headlamps in a system comprising an image sensor generating a plurality of pixel levels from a scene being imaged and a controller to generate headlamp control signals, the method comprising the steps of:

receiving pixel levels from the image sensor;

analyzing the image input from the image sensor using different thresholds for different pixels based on their pixel location, the different thresholds rendering the image sensor more sensitive to one side of the car than the other side of the car; and

selectively generating a headlamp control signal in accordance with the results of the steps of analyzing.

81. The method of claim 80, wherein the step of analyzing the image includes using a spatial look-up table, the spatial look-up table having different thresholds for different pixels based on their pixel location.

82. The method of claim 81, wherein the spatial look-up table has values which render the image sensor more sensitive to one side of the car than the other side of the car.

83. The method of claim 80, wherein the image sensor is more sensitive to the side of the car on which the driver sits.

84. The method of claim 80, wherein the high beams are controlled responsive to those pixels from the image sensor exceeding its respective pixel threshold.