Method and device for tracking-based visibility range estimation

Patent metadata

Field	Value
Publication number	US-9727792-B2
Application number	US-201514703278-A
Country	US
Kind code	B2
Filing date	May 4, 2015
Priority date	May 2, 2014
Publication date	Aug 8, 2017
Grant date	Aug 8, 2017

Abstract

A method is provided for tracking-based visibility range estimation for a vehicle, the method including a step of tracking an object detected in a first image at a first point in time and in a second image at a second point in time, a step of ascertaining a first object luminance of the object and a first distance to the object at the first point in time and also ascertaining a second object luminance of the object and a second distance to the object at the second point in time, and also a step of determining an atmospheric extinction coefficient using the first object luminance, the second object luminance, the first distance, and the second distance, the atmospheric extinction coefficient being in direct correlation to visibility range.

First claim

What is claimed is:

1. A method for supporting safe driving of a vehicle, the method comprising:
tracking, by a driver assistance system of the vehicle, an object depicted in a first image detected at a first point in time and in at least one second image detected at a second point in time;
ascertaining, by the driver assistance system, a first object luminance of the object and a first distance to the object at the first point in time;
ascertaining, by the driver assistance system, a second object luminance of the object and a second distance to the object at the second point in time; and
determining, by the driver assistance system, an atmospheric extinction coefficient using the first object luminance, the second object luminance, the first distance, and the second distance, the atmospheric extinction coefficient being in direct correlation to a visibility range;
estimating, by the driver assistance system, the visibility range using the determined atmospheric extinction coefficient; and
warning a driver or adapting a driving of the vehicle, by the driver assistance system, based on the estimated visibility range;
wherein the atmospheric extinction coefficient is determined using a one-dimensional equation of:

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2. A method for supporting safe driving of a vehicle, the method comprising:
tracking, by a driver assistance system of the vehicle, an object depicted in a first image detected at a first point in time and in at least one second image detected at a second point in time;
ascertaining, by the driver assistance system, a value of a first overall luminance corresponding to the object and a value of a first distance to the object at the first point in time;
ascertaining, by the driver assistance system, a value of a second overall luminance corresponding to the object and a value of a second distance to the object at the second point in time;
fitting, by regression, the value of the first overall luminance, the value of the second overall luminance, the value of the first distance, and the value of the second distance to a model that models overall luminance against parameters that include an air luminance, a luminance of the object, object distance, and an atmospheric extinction coefficient, thereby obtaining an estimate of the air luminance, the luminance of the object, and the atmospheric extinction coefficient;
estimating, by the driver assistance system, the visibility range using the estimated atmospheric extinction coefficient; and
warning a driver or adapting a driving of the vehicle, by the driver assistance system, based on the estimated visibility range.

3. The method as recited in claim 1 , wherein the atmospheric extinction coefficient is determined using an estimation method from the one-dimensional equation.

4. The method as recited in claim 1 , wherein the atmospheric extinction coefficient is determined using an iterative Newton's method.

5. The method as recited in claim 1 , further comprising:
detecting the first image at the first point in time and the second image at a second point in time following the first point in time, wherein:
in the step of detecting, the first and second images are detected using at least one image detection device,
the first and second images represent an item as the object from surroundings of the at least one image detection device, and
a distance is present between the at least one image detection device and the item.

6. The method as recited in claim 1 , wherein:
at least one additio

Assignees

• Bosch Gmbh Robert

Inventors

• Martini Johannes
• Stopper Ulrich
• Lenor Stephan
• Weber Stefan

Classifications

• G01N21/538 Primary

  for determining atmospheric attenuation and visibility · CPC title

• G06V20/56

  exterior to a vehicle by using sensors mounted on the vehicle · CPC title

• G06F18/24

  Classification techniques · CPC title

• G06K9/00791 Primary

  Physics · mapped topic

• B60W40/02

  related to ambient conditions · CPC title