Method for regulating the beam range of at least one headlamp of a vehicle and light control device

• US 9,114,754 B2
• Filed: 04/23/2012
• Issued: 08/25/2015
• Est. Priority Date: 04/28/2011
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Ehlgen, Tobias, Nordbruch, Stefan, Foltin, Johannes
• Primary Examiner(s): Badii, Behrang
• Assistant Examiner(s): TESTARDI, DAVID A
• Application Number:
  US14/114,083
• Publication Number:
  US 20140129081A1
• Time in Patent Office: 1,219 Days
• Field of Search: 701/36
• US Class Current: 1/1
• CPC Class Codes: B60Q 1/0023 the element being a sensor, e.g. distance sensor, camera
• CPC Class Codes: B60Q 1/10 due to vehicle inclination, e.g. due to load distribution
• CPC Class Codes: B60Q 1/115 by electric means details of the electric drive components, e.g. motors, shafts, ball joints B60Q1/076
• CPC Class Codes: B60Q 2200/38 Automatic calibration of motor-driven means for adjusting headlamps, i.e. when switching on the headlamps, not during mounting at factories
• CPC Class Codes: B60Q 2300/324 Road inclination, e.g. uphill or downhill
• CPC Class Codes: G01M 11/064 by using camera or other imaging system for the light analysis
• CPC Class Codes: G01M 11/068 with part of the measurements done from inside the vehicle

Abstract

A method for beam range regulation of at least one headlamp of a vehicle includes: reading in a camera image of at least one camera of the vehicle, the camera image including at least a part of a representation of a projection surface of a light cone of the headlamp in front of the vehicle; determining at least one coordinate of at least one predefined brightness transition and/or of a predefined brightness inhomogeneity in the camera image; comparing the coordinate with a target coordinate in order to obtain a difference of the coordinate from the target coordinate, the target coordinate representing a coordinate at which the predefined brightness transition or the predefined brightness inhomogeneity is expected; and controlling the headlamp with a beam range modification signal that is a function of the difference, in order to modify the beam range.

Claims

1. A method for beam range regulation of at least one headlamp of a vehicle, comprising:

reading in a camera image of at least one camera of the vehicle, wherein the camera image includes at least a part of a representation of a projection surface of a light cone of the headlamp in front of the vehicle;

determining at least one coordinate of at least one of (i) predefined brightness transition in the camera image, and (ii) a predefined brightness inhomogeneity in the camera image, and additionally determining an unevenness contour of the surface of a roadway by determining a height contour of the roadway surface over a predefined distance by traveling the roadway with the vehicle over the predefined distance;

comparing the determined coordinate to a target coordinate to obtain a difference between the determined coordinate and the target coordinate, wherein the target coordinate represents a coordinate at which the at least one of the predefined brightness transition and the predefined brightness inhomogeneity is expected, and wherein the target coordinate is adapted corresponding to the unevenness contour of the roadway surface for a repeated pitching motion of the vehicle caused by the unevenness contour of the roadway surface; and

controlling the headlamp with a beam range modification signal to modify the beam range, wherein the beam range modification signal is a function of the difference between the determined coordinate and the target coordinate.

2. The method as recited in claim 1, further comprising:

initializing the headlamp before the step of reading in the camera image, wherein the initializing includes controlling the headlamp with an initialization signal in order to modify the size of the projection surface.

3. The method as recited in claim 2, wherein:

the determining step additionally includes determining at least a part of an outline of the projection surface; and

the comparing step additionally includes comparing the outline of the projection surface to a target outline in order to obtain a difference.

4. The method as recited in claim 3, wherein:

in the comparing step, the target coordinate is read out from a memory, the target coordinate having been determined in a preceding step of calibration and stored in the memory.

5. The method as recited in claim 1, further comprising:

determining a reflectivity of a roadway in front of the vehicle from the camera image information, wherein the determined reflectivity is used in the determining of the at least one coordinate.

6. The method as recited in claim 1, wherein:

the unevenness contour of the roadway surface is determined by one of (i) determining a height contour of a roadway by traveling the roadway with the vehicle, or (ii) a pitch sensor.

7. The method as recited in claim 1, further comprising:

modifying the target coordinate by adapting the target coordinate to a variable parameter using a learning algorithm.

8. A light control device for beam range regulation of at least one headlamp of a vehicle, comprising:

a device for reading in a camera image of at least one camera of the vehicle, wherein the camera image includes at least a part of a representation of a projection surface of a light cone of the headlamp in front of the vehicle;

a device for determining at least one coordinate of at least one of (i) predefined brightness transition in the camera image, and (ii) a predefined brightness inhomogeneity in the camera image, and for additionally determining an unevenness contour of the surface of a roadway by determining a height contour of the roadway surface over a predefined distance by traveling the roadway with the vehicle over the predefined distance;

a device for comparing the determined coordinate to a target coordinate to obtain a difference between the determined coordinate and the target coordinate, wherein the target coordinate represents a coordinate at which the at least one of the predefined brightness transition and the predefined brightness inhomogeneity is expected, and wherein the target coordinate is adapted corresponding to the unevenness contour of the roadway surface for a repeated pitching motion of the vehicle caused by the unevenness contour of the roadway surface; and

a device for controlling the headlamp with a beam range modification signal to modify the beam range, wherein the beam range modification signal is a function of the difference between the determined coordinate and the target coordinate.

9. A non-transitory computer-readable data storage medium storing a computer program having program codes which, when executed on a computer, performs a method for beam range regulation of at least one headlamp of a vehicle, the method comprising:

reading in a camera image of at least one camera of the vehicle, wherein the camera image includes at least a part of a representation of a projection surface of a light cone of the headlamp in front of the vehicle;

determining at least one coordinate of at least one of (i) predefined brightness transition in the camera image, and (ii) a predefined brightness inhomogeneity in the camera image, and additionally determining an unevenness contour of the surface of a roadway by determining a height contour of the roadway surface over a predefined distance by traveling the roadway with the vehicle over the predefined distance;

comparing the determined coordinate to a target coordinate to obtain a difference between the determined coordinate and the target coordinate, wherein the target coordinate represents a coordinate at which the at least one of the predefined brightness transition and the predefined brightness inhomogeneity is expected, and wherein the target coordinate is adapted corresponding to the unevenness contour of the roadway surface for a repeated pitching motion of the vehicle caused by the unevenness contour of the roadway surface; and

controlling the headlamp with a beam range modification signal to modify the beam range, wherein the beam range modification signal is a function of the difference between the determined coordinate and the target coordinate.