Method and device for identifying blooming candidates in a Lidar measurement

Patent metadata

Field	Value
Publication number	US-12449548-B2
Application number	US-202118251295-A
Country	US
Kind code	B2
Filing date	Sep 8, 2021
Priority date	Nov 2, 2020
Publication date	Oct 21, 2025
Grant date	Oct 21, 2025

Abstract

A method for identifying blooming candidates in a Lidar measurement may include providing a distance-based histogram of points of a point cloud generated in the Lidar measurement. In the histogram, clusters of points having the same distance to a Lidar sensor carrying out the Lidar measurement are identified and intensities of the points of a cluster are evaluated. If the cluster contains points, the intensities of which exceed in each case a predefined limit value, those points of the cluster, the intensities of which do not exceed in each case the predefined limit value and in particular fall below the predefined limit value by more than a predefined threshold value, are classified as blooming candidates.

First claim

The invention claimed is:

1. A method for identifying blooming candidates in a Lidar measurement, comprising:
a distance-based histogram of points is created for a point cloud generated by the Lidar measurement,
clusters of points at a same distance to a Lidar sensor taking the Lidar measurement are identified in the histogram,
intensities of points in a cluster are evaluated, and
then, in response to the cluster containing points whose intensities exceed a predefined limit value respectfully, those points in the cluster whose intensities do not exceed the predefined limit value respectfully, and lie below the predefined limit value by more than a predefined threshold value, are classified as blooming candidates,
wherein points in that cluster whose intensities exceed the predefined limit value respectfully are classified as highly reflective measurement values and as true-positive measurement values,
wherein when the point cloud is generated:
linear laser pulses and/or rectangular laser pulses are sent out from a transmitter of the Lidar sensor,
for each laser pulse reflected by an object that appears on the receiver of the Lidar sensor, a point is generated in the point cloud,
to determine a distance to objects in a surroundings of the Lidar sensor, a time is detected until a reflected laser pulse reaches a specific receiver of the Lidar sensor, and
a value for a determined distance is assigned to each point, and

control at least partially autonomous vehicle or robot based on data collected in the Lidar measurements, and the points classified as blooming candidates.

2. A method for identifying blooming candidates in a Lidar measurement, comprising:
a distance-based histogram of points is created for a point cloud generated by the Lidar measurement,
clusters of points at a same distance to a Lidar sensor taking the Lidar measurement are identified in the histogram,
intensities of points in a cluster are evaluated, and
then, in response to the cluster containing points whose intensities exceed a predefined limit value respectfully, those points in the cluster whose intensities do not exceed the predefined limit value respectfully, and lie below the predefined limit value by more than a predefined threshold value, are classified as blooming candidates,
wherein points in that cluster whose intensities exceed the predefined limit value respectfully are classified as highly reflective measurement values and as true-positive measurement values,
wherein when the point cloud is generated:
linear laser pulses and/or rectangular laser pulses are sent out from a transmitter of the Lidar sensor,
for each laser pulse reflected by an object that appears on the receiver of the Lidar sensor, a point is generated in the point cloud,
to determine a distance to objects in a surroundings of the Lidar sensor, a time is detected until a reflected laser pulse reaches a specific receiver of the Lidar sensor, and a value for a determined distance is assigned to each point, wherein via the laser pulses the surroundings are scanned separately in rows, in columns, and/or in multiple sub-areas, and
control a at least partially autonomous vehicle or robot based on data collected in the Lidar measurements, and the points classified as blooming candidates.

3. The method as in claim 1 , wherein the surroundings of the Lidar sensor are divided into multiple sub-areas and a distance-based histogram is created from points in a point cloud generated by the Lidar measurement.

4. A method for identifying blooming candidates in a Lidar measurement, comprising:
a distance-based histogram of points is created for a point cloud generated by the Lidar measurement,
clusters of points at a same distance to a Lidar sensor taking the Lidar measurement are identified in the histogram,
intensities of points in a cluster are evaluated, and then, in response to the cluster containing points whose intensities exceed a predefined limit value respectfully, those points in the cluster whose intensities do not exceed the predefined limit value respectfully, and lie below the predefined limit value by more than a predefined threshold value, are classified as blooming candidates,
wherein during operation of a partially automated or autonomously operable vehicle or robot, control of the vehicle or robot is based on data collected in the Lidar measurements, and the points classified as blooming candidates are taken into account.

Assignees

• Mercedes Benz Group Ag
• Bosch Gmbh Robert

Inventors

• Peter David
• Pfender Matthias
• Enzweiler Markus
• Fink Axel
• Lehner Philipp

Classifications

• G01S17/89

  for mapping or imaging · CPC title

• G01S7/4865

  Time delay measurement, e.g. time-of-flight measurement, time of arrival measurement or determining the exact position of a peak (peak detection in noise, signal conditioning G01S7/487) · CPC title

• G01S7/4816

  of receivers alone · CPC title

• G01S13/931

  of land vehicles · CPC title

• G01S13/865

  Combination of radar systems with lidar systems · CPC title