Collision avoidance assistance device and collision avoidance assistance method

Patent metadata

Field	Value
Publication number	US-9714050-B2
Application number	US-201314770915-A
Country	US
Kind code	B2
Filing date	Mar 28, 2013
Priority date	Mar 28, 2013
Publication date	Jul 25, 2017
Grant date	Jul 25, 2017

Abstract

A collision avoidance assistance device configured to perform driver steering assistance to avoid a collision between a vehicle and an obstacle, the device includes a steering control unit configured to perform the steering assistance in a case where it is determined that there is a possibility of the collision between the vehicle and the obstacle. During a period from commencement of the steering assistance to elapsing of a first time determined by response characteristics of a lateral acceleration of the vehicle, the steering control unit is configured to rotate a steering wheel of the vehicle in a collision avoidance direction by a control amount determined based on a steering holding force of the driver.

First claim

The invention claimed is:

1. A collision avoidance assistance device configured to perform driver steering assistance to avoid a collision between a vehicle and an obstacle, the device comprising:
a steering control unit configured to perform the steering assistance in a case where it is determined that there is a possibility of the collision between the vehicle and the obstacle,
wherein, during a period from commencement of the steering assistance to elapsing of a first time determined by response characteristics of a lateral acceleration of the vehicle, the steering control unit is configured to rotate a steering wheel of the vehicle in a collision avoidance direction by a control amount determined based on a steering holding force of the driver,
wherein the control amount is set to a value greater than the steering holding force, and
wherein the first time is set to be shorter than a delay time that is a period during which the lateral acceleration on the vehicle is suppressed when the steering assistance is performed by the steering control unit.

2. The collision avoidance assistance device according to claim 1 ,
wherein, at the time of or after commencement of the steering assistance, the steering control unit is configured to end the steering assistance in response to detecting the steering operation of the steering wheel by the driver as being equal to or greater than a predetermined amount.

3. The collision avoidance assistance device according to claim 1 , further comprising:
a target control amount calculation unit configured to calculate a target control amount for travelling on a target path through which the vehicle is to travel for avoiding the collision with the obstacle; and
a control amount adjustment unit configured to obtain a designated control amount by adding an initial control amount to the target control amount during the period from commencement of the steering assistance to elapsing of the first time, and to adopt the target control amount as the designated control amount after the first time has elapsed since commencement of the steering assistance,
wherein the steering control unit is configured to perform the steering assistance by rotating the steering wheel by the designated control amount.

4. The collision avoidance assistance device according to 1 , further comprising:
a gear ratio control unit configured to variably control a gear ratio which is a ratio between a rotation angle of the steering wheel of the vehicle and a tire angle of the vehicle,
wherein the gear ratio control unit is configured to set the gear ratio such that the rotation angle of the steering wheel becomes greater than the tire angle during a period from commencement of the steering assistance to elapsing of a second time which is longer than the first time determined by response characteristics of a lateral acceleration of the vehicle, and
wherein, during the period from commencement of the steering assistance to elapsing of the second time, the steering control unit is configured to rotate the steering wheel in the collision avoidance direction by the control amount determined based on the steering holding force of the driver.

5. A collision avoidance assistance method for performing driver steering assistance to avoid a collision between a vehicle and an obstacle, the method comprising:
a steering control step of performing the steering assistance in a case where it is determined that there is a possibility of the collision between the vehicle and the obstacle,
wherein, in the steering control step, during a period from commencement of the steering assistance to elapsing of a first time determined by response characteristics of a lateral acceleration of the vehicle, the steering wheel of the vehicle is rotated in the collision avoidance direction by the control amount determined based on the steering holding force of the driver,
wherein the control amount is set to a value greater than the steering holding force, and
wherein the first time is set to be shorter than a delay time that is a period during which the lateral acceleration on the vehicle is suppressed when the steering assistance is performed by the steering control unit.

Assignees

• Toyota Motor Co Ltd

Inventors

• Morotomi Kohei
• Yamada Yoshihisa
• Kasai Eiji
• Akiyama Tomonori

Classifications

• B60T2260/02

  Active Steering, Steer-by-Wire · CPC title

• B62D15/0265 Primary

  Automatic obstacle avoidance by steering · CPC title

• B62D15/025

  Active steering aids, e.g. helping the driver by actively influencing the steering system after environment evaluation (B62D1/28 takes precedence) · CPC title

• B60T7/22

  initiated by contact of vehicle, e.g. bumper, with an external object, e.g. another vehicle {, or by means of contactless obstacle detectors mounted on the vehicle} · CPC title

• B60T2201/022

  Collision avoidance systems · CPC title