Vehicle behavior control device

Patent metadata

Field	Value
Publication number	US-2017129481-A1
Application number	US-201615342820-A
Country	US
Kind code	A1
Filing date	Nov 3, 2016
Priority date	Nov 6, 2015
Publication date	May 11, 2017
Grant date	—

Abstract

The vehicle behavior control device comprises a PCM configured to decide a target additional deceleration. The PCM is operable: to correct the target additional deceleration in such a manner that it is reduced by multiplying the target additional deceleration by a coefficient K1 set according to a vehicle speed, a coefficient K2 set according to a steering wheel angle, a coefficient K3 set according to an accelerator position and a coefficient K4 decided according to a required deceleration; when a value derived by multiplying the target additional deceleration by K1 and K2 is less than a threshold D T , to stop a torque reduction control; and, when the value derived by multiplying the target additional deceleration by K1 and K2 is equal to or greater than D T , and a value derived by multiplying the target additional deceleration by K3 and K4 is less than D T , to maintain the torque reduction control.

First claim

What is claimed is:

1 . A vehicle behavior control device for controlling a behavior of a vehicle having steerable front road wheels, comprising a driving force controller configured to decide a target additional deceleration to be added to the vehicle, according to a yaw rate-related quantity which is related to a yaw rate of the vehicle, and reduce a driving force for the vehicle so as to realize the target additional deceleration,
wherein the driving force controller is operable:
to correct the target additional deceleration in such a manner that it is reduced by multiplying the target additional deceleration by: a vehicle speed coefficient of 1 or less, which is set according to a vehicle speed of the vehicle; a steering wheel angle coefficient of 1 or less, which is set according to a steering wheel angle of the vehicle; an accelerator position coefficient of 1 or less, which is set according to an accelerator position of the vehicle; and a required deceleration coefficient of 1 or less, which is decided according to a required deceleration of the vehicle;
when a value derived by multiplying the target additional deceleration by the vehicle speed coefficient and the steering wheel angle coefficient is less than a given determination threshold, to stop control of reducing the driving force; and,
when the value derived by multiplying the target additional deceleration by the vehicle speed coefficient and the steering wheel angle coefficient is equal to or greater than the determination threshold, and a value derived by multiplying the target additional deceleration by the accelerator position coefficient and the required deceleration coefficient is less than the determination threshold, to perform the control of reducing the driving force for the vehicle so as to realize the corrected target additional deceleration.

2 . The vehicle behavior control device as recited in claim 1 , wherein the vehicle speed coefficient is set such that it is reduced to a smaller value as the vehicle speed becomes smaller.

3 . The vehicle behavior control device as recited in claim 1 , wherein the steering wheel angle coefficient is set such that it is reduced to a smaller value as the steering wheel angle becomes smaller.

4 . The vehicle behavior control device as recited in claim 1 , wherein the accelerator position coefficient is set such that it is reduced to a smaller value as the accelerator position becomes larger.

5 . The vehicle behavior control device as recited in claim 1 , wherein the required deceleration coefficient is set such that it is reduced to a smaller value as the required deceleration becomes larger.

6 . The vehicle behavior control device as recited in claim 1 , wherein the driving force controller is operable, when the steering wheel angle of the vehicle is increasing and the yaw rate-related quantity is increasing, to reduce the driving force according to the yaw rate-related quantity being increasing.

7 . A vehicle control device comprising a controller to which at least a steering wheel angle, an accelerator position, a vehicle speed and a brake fluid pressure are input, and which is configured to control a driving force output from a driving force generator based on the steering wheel angle, the accelerator position, the vehicle speed and the brake fluid pressure, wherein the controller is configured to:
when the steering wheel angle is increasing and the steering speed is not decreasing,
acquire an additional deceleration to be added to the vehicle according to the steering speed with reference to a map defining the additional deceleration to be set according to the steering speed;
acquire a correction coefficient K1 set according to the vehicle speed, a correction coefficient K2 set according to the steering wheel angle, a correction coefficient K3 set according to the accelerator position and a correction coefficient K4 decided according to a deceleration to be generated in the vehicle calculated based on the brake fluid pressure;
correct the additional deceleration in such a manner that it is reduced by multiplying the additional deceleration by the correction coefficients K1, K2, K3 and K4 of 1 or less;
set the corrected additional deceleration to 0, when the corrected additional deceleration is less than a given determination threshold and a value derived by multiplying the additional deceleration by the correction coefficients K1 and K2 is less than the given determination threshold;
set the corrected additional deceleration to 0, when the corrected additional deceleration is less than the given determination threshold, the value derived by multiplying the additional deceleration by the correction coefficients K1 and K2 is equal to or greater than the given determination threshold and a value derived by multiplying the additional deceleration by the correction coefficients K3 and K4 is equal to or greater than the given determination threshold;
maintain the corrected additional deceleration, when the corrected additional deceleration is less than the given determination threshold, the value derived by multiplying the additional deceleration by the correction coefficients K1 and K2 is equal to or greater than the given determination threshold and the value derived by multiplying the additional deceleration by the correction coefficients K3 and K4 is less than the given determination threshold, or when the corrected additional deceleration is equal to or greater than the given determination threshold; and
reduce the driving force so as to generate the corrected additional deceleration;
reduce the driving force so as to generate the additional deceleration at the maximum steering speed when the steering wheel angle is increasing and the steering speed is decreasing; and increase the driving force so as to reduce the additional deceleration when the steering wheel angle is not increasing.

Assignees

• Mazda Motor

Inventors

• Umetsu Daisuke
• Sunahara Osamu

Classifications

• B60W10/06

  including control of combustion engines · CPC title

• B60W2520/10

  Longitudinal speed · CPC title

• B60W2720/125

  Lateral acceleration · CPC title

• B60W2540/18

  Steering angle · CPC title

• B60W2510/182

  Brake pressure, e.g. of fluid or between pad and disc · CPC title