Vehicle motion control system

• US 6,278,929 B1
• Filed: 10/26/1999
• Issued: 08/21/2001
• Est. Priority Date: 10/30/1998
• Status: Expired due to Term

• Current Assignee: Advics Company Limited (Aisin Corp.)
• Original Assignee: Aisin Seiki Co., Ltd. (Aisin Corp.)
• Inventors: Itoh, Takayuki, Tozu, Kenji
• Primary Examiner(s): LOUIS JACQUES, JACQUES H
• Application Number:
  US09/427,115
• Time in Patent Office: 665 Days
• Field of Search: 701/70, 701/36, 701/37, 701/38, 701/41, 701/71, 701/78, 701/79, 701/72, 701/83, 303/116.1, 303/113.2, 303/140, 303/146, 303/10, 303/163, 303/166, 303/174, 303/147, 303/188, 303/155, 303/167, 180/197
• US Class Current: 701/70
• CPC Class Codes: B60T 8/1755 Brake regulation specially adapted to control the stability of the vehicle, e.g. taking into account yaw rate or transverse acceleration in a curve road vehicle drive control systems for control of driving stability otherwise than by controlling a particular sub-unit B60W30/02

Abstract

The present invention is directed to a vehicle motion control system, which includes a hydraulic braking pressure control apparatus for controlling braking force applied to each wheel of a vehicle at least in response to depression of a brake pedal. A vehicle condition monitor is disposed in the vehicle for monitoring a condition of the vehicle in motion, and a vehicle condition determining device is provided for determining stability of the vehicle in motion, including a turning motion of the vehicle on the basis of the output of the monitor. A braking force controller is provided for controlling the pressure control apparatus in response to the result of determination of the vehicle condition determining device to control the braking force applied to each wheel of the vehicle. A starting reference setting device is provided for setting a starting reference to start the braking force control by the braking force controller in response to the result of determination of the vehicle condition determining device. Then, an error estimating device is provided for estimating an error caused by the monitor, and a correction device is provided for correcting the starting reference set by the starting reference setting device in response to the error estimated by the error estimating device.

Claims

1. A vehicle motion control system for maintaining stability of an automotive vehicle when said vehicle in motion, comprising:

a hydraulic braking pressure control apparatus for controlling braking force applied to each wheel of said vehicle at least in response to depression of a brake pedal;

vehicle condition monitor means disposed in said vehicle for monitoring a condition of said vehicle in motion;

vehicle condition determining means for determining stability of said vehicle in motion, including a turning motion of said vehicle on the basis of the output of said monitor means;

braking force control means for controlling said hydraulic braking pressure control apparatus in response to the result of determination of said vehicle condition determining means to control the braking force applied to each wheel of said vehicle;

starting reference setting means for setting a starting reference to start the braking force control by said braking force control means in response to the result of determination of said vehicle condition determining means;

error estimating means for estimating an error caused by said monitor means; and

correction means for correcting the starting reference set by said starting reference setting means in response to the error estimated by said error estimating means;

wherein said correction means is adapted to correct the starting reference set by said starting reference setting means to be relatively higher, when said error estimating means estimated the error resulted from a distance between the center of gravity of said vehicle and the center of said monitor means mounted on said vehicle.

2. The vehicle motion control system of claim 1, wherein said vehicle condition monitor means includes vehicle speed detecting means for detecting a vehicle speed, a lateral acceleration detecting means for detecting a lateral acceleration of said vehicle, and a yaw rate detecting means for detecting a yaw rate of said vehicle.

3. The vehicle motion control system of claim 2, wherein said vehicle condition monitor means includes vehicle slip angular velocity calculating means for calculating a vehicle slip angular velocity on the basis of the vehicle speed detected by said vehicle speed detecting means, the lateral acceleration detected by said lateral acceleration detecting means, and the yaw rate detected by said yaw rate detecting means, and includes vehicle slip angle calculating means for integrating the vehicle slip angular velocity to obtain a vehicle slip angle, and wherein said starting reference setting means is adapted to set the starting reference in response to the result calculated by said vehicle slip angular velocity calculating means, and the result calculated by said vehicle slip angle calculating means.

4. A vehicle motion control system for maintaining stability of an automotive vehicle when said vehicle in motion, comprising:

a hydraulic braking pressure control apparatus for controlling braking force applied to each wheel of said vehicle at least in response to depression of a brake pedal;

vehicle condition monitor means disposed in said vehicle for monitoring a condition of said vehicle in motion;

vehicle condition determining means for determining stability of said vehicle in motion, including a turning motion of said vehicle on the basis of the output of said monitor means;

braking force control means for controlling said hydraulic braking pressure control apparatus in response to the result of determination of said vehicle condition determining means to control the braking force applied to each wheel of said vehicle;

starting reference setting means for setting a starting reference to start the braking force control by said braking force control means in response to the result of determination of said vehicle condition determining means;

error estimating means for estimating an error caused by said monitor means; and

correction means for correcting the starting reference set by said starting reference setting means in response to the error estimated by said error estimating means;

wherein said correction means is adapted to correct the starting reference set by said starting reference setting means to be relatively higher, when said error estimating means estimated the error resulted from a zero point set for said monitor means.

5. The vehicle motion control system of claim 4, wherein said vehicle condition monitor means includes vehicle speed detecting means for detecting a vehicle speed, a lateral acceleration detecting means for detecting a lateral acceleration of said vehicle, and a yaw rate detecting means for detecting a yaw rate of said vehicle.

6. The vehicle motion control system of claim 5, wherein said vehicle condition monitor means includes vehicle slip angular velocity calculating means for calculating a vehicle slip angular velocity on the basis of the vehicle speed detected by said vehicle speed detecting means, the lateral acceleration detected by said lateral acceleration detecting means, and the yaw rate detected by said yaw rate detecting means, and includes vehicle slip angle calculating means for integrating the vehicle slip angular velocity to obtain a vehicle slip angle, and wherein said starting reference setting means is adapted to set the starting reference in response to the result calculated by said vehicle slip angular velocity calculating means, and the result calculated by said vehicle slip angle calculating means.

7. A vehicle motion control system for maintaining stability of an automotive vehicle when said vehicle in motion, comprising:

a hydraulic braking pressure control apparatus for controlling braking force applied to each wheel of said vehicle at least in response to depression of a brake pedal;

vehicle condition monitor means disposed in said vehicle for monitoring a condition of said vehicle in motion;

vehicle condition determining means for determining stability of said vehicle in motion, including a turning motion of said vehicle on the basis of the output of said monitor means;

braking force control means for controlling said hydraulic braking pressure control apparatus in response to the result of determination of said vehicle condition determining means to control the braking force applied to each wheel of said vehicle;

starting reference setting means for setting a starting reference to start the braking force control by said braking force control means in response to the result of determination of said vehicle condition determining means;

error estimating means for estimating an error caused by said monitor means; and

correction means for correcting the starting reference set by said starting reference setting means in response to the error estimated by said error estimating means;

wherein said correction means is adapted to correct the starting reference set by said starting reference setting means to be relatively higher, when said error estimating means estimated the error resulted from inclination of said vehicle in a lateral direction thereof.

8. The vehicle motion control system of claim 7, wherein said vehicle condition monitor means includes vehicle speed detecting means for detecting a vehicle speed, a lateral acceleration detecting means for detecting a lateral acceleration of said vehicle, and a yaw rate detecting means for detecting a yaw rate of said vehicle.

9. The vehicle motion control system of claim 8, wherein said vehicle condition monitor means includes vehicle slip angular velocity calculating means for calculating a vehicle slip angular velocity on the basis of the vehicle speed detected by said vehicle speed detecting means, the lateral acceleration detected by said lateral acceleration detecting means, and the yaw rate detected by said yaw rate detecting means, and includes vehicle slip angle calculating means for integrating the vehicle slip angular velocity to obtain a vehicle slip angle, and wherein said starting reference setting means is adapted to set the starting reference in response to the result calculated by said vehicle slip angular velocity calculating means, and the result calculated by said vehicle slip angle calculating means.