Method and apparatus for representing environmental elements, system, and vehicle/robot

Patent metadata

Field	Value
Publication number	US-11216951-B2
Application number	US-201916693161-A
Country	US
Kind code	B2
Filing date	Nov 22, 2019
Priority date	May 25, 2017
Publication date	Jan 4, 2022
Grant date	Jan 4, 2022

Abstract

A computer-implemented method for representing environmental elements includes receiving scan data comprising at least a point cloud representing at least an environmental element from a sensor, segmenting the point cloud into point clusters, and partitioning the point clusters into hierarchical grids. The method also includes establishing a Gaussian distribution for points in each cell of each of the hierarchical grids, and constructing a Gaussian Mixture Model based on the Gaussian distribution for representing the environmental element.

First claim

What is claimed is:

1. A computer-implemented method for representing environmental elements, comprising:
receiving scan data comprising at least a point cloud representing at least an environmental element from a sensor;
segmenting the point cloud into point clusters using a region growing algorithm with a predetermined criterion of smooth;
partitioning the point clusters into hierarchical grids;
establishing a Gaussian distribution for points in each cell of each of the hierarchical grids; and
constructing a Gaussian Mixture Model based on the Gaussian distribution for representing the environmental element,
wherein the predetermined criterion of smooth is derived by:
for each point of the point cloud, getting its neighboring points;
transforming the neighboring points into a local operation plane;
for each point of the point cloud, calculating principal curvatures of the local surface;
calculating surface curvature at one point of the point cloud to the direction of another point of the point cloud, surface curvature at the another point to the direction of the one point, and torsion of surface from the one point to the direction of the another point; and
establishing the predetermined criterion of smooth as the absolute value of the surface curvature at the one point to the direction of the another point being smaller than a threshold, the absolute value of the surface curvature at the another point to the direction of the one point being smaller than a threshold, and the absolute value of the torsion of surface from the one point to the direction of the another point being smaller than a threshold, and

wherein the surface curvature K ij at the one point to the direction of the another point G p j is denoted as:

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Assignees

• Bayerische Motoren Werke Ag

Inventors

• Doemling Maximilian
• Granzow Sebastian
• Jiang Wanli
• Li Qianshan
• Li Jianpeng
• Lv Shuhan
• Xu Hongshan
• Xu Tao

Classifications

• G06T7/187 Primary

  involving region growing; involving region merging; involving connected component labelling · CPC title

• G06V20/64

  Three-dimensional [3D] objects · CPC title

• G06V20/58

  Recognition of moving objects or obstacles, e.g. vehicles or pedestrians; Recognition of traffic objects, e.g. traffic signs, traffic lights or roads · CPC title

• G06V10/426

  Graphical representations · CPC title

• G06V20/10

  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 title