Lane change path planning algorithm for autonomous driving vehicle

Patent metadata

Field	Value
Publication number	US-9428187-B2
Application number	US-201414297415-A
Country	US
Kind code	B2
Filing date	Jun 5, 2014
Priority date	Jun 5, 2014
Publication date	Aug 30, 2016
Grant date	Aug 30, 2016

Abstract

A system and method for providing path planning and generation for automated lane centering and/or lane changing purposes for a vehicle traveling on a roadway, where the method employs roadway measurement values from a vision camera within an effective range of the camera and roadway measurement values from a map database beyond the range of the camera. The method uses the roadway measurement values from the camera to determine a desired path along a first segment of the roadway and identifies an end of the first segment based on how accurately the camera defines the roadway. The method then uses the roadway measurement values from the map database to determine the desired path along a second segment of the roadway that begins at the end of the first segment, where a transition from the first segment to the second segment is smooth.

First claim

What is claimed is:

1. A method for generating a desired path for a vehicle to follow along a roadway, said vehicle including at least one forward-looking camera and a map database, said method comprising:
providing roadway measurement values from the camera that identifies locations on the roadway;
providing roadway measurement values from the map database that identifies locations on the roadway;
determining the desired path along a first segment of the roadway using the roadway measurement values from the camera;
identifying an end of the first segment based on an effective range of the camera; and
determining the desired path along a second segment of the roadway using the roadway measurement values from the map database, where the second segment begins at the end of the first segment.

2. The method according to claim 1 wherein the method automatically calculates multiple segments to define the desired path for the vehicle to follow for both lane centering and lane changing purposes.

3. The method according to claim 1 wherein determining the desired path along multiple segments includes solving a fifth-order polynomial equation.

4. The method according to claim 1 wherein identifying the end of the first segment includes determining an error between the roadway measurement values from the camera and the desired path along the first segment.

5. The method according to claim 4 wherein identifying the end of the first segment includes employing a cost function that identifies the difference between the measured values and the desired path and determining when the cost function exceeds a predetermined cost function threshold.

6. The method according to claim 5 wherein identifying the end of the first segment includes minimizing the cost function J as:

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where the solution of the cost function J is given as:

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…

Assignees

• Gm Global Tech Operations Llc

Inventors

• Lee Jin-Woo

Classifications

• B60W2710/0605

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• B60W2710/18

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• B60W2552/30

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• B60W10/06

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• B60W10/18

  including control of braking systems · CPC title