Turning behavior control device for vehicle

• US 20060086543A1
• Filed: 10/24/2005
• Published: 04/27/2006
• Est. Priority Date: 10/25/2004
• Status: Active Grant

• Current Assignee: Mitsubishi Jidosha Kogyo Kabushiki Kaisha
• Original Assignee: Mitsubishi Jidosha Kogyo Kabushiki Kaisha
• Inventors: Motoyama, Sumio
• Granted Patent: US 7,643,922 B2
• Time in Patent Office: Days
• US Class Current: 180/6.320
• CPC Class Codes: B60T 2260/02 Active Steering, Steer-by-Wire
• 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
• CPC Class Codes: B60W 10/16 Axle differentials, e.g. for dividing torque between left and right wheels
• CPC Class Codes: B60W 10/184 with wheel brakes
• CPC Class Codes: B60W 10/20 including control of steering systems
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2520/14 Yaw
• CPC Class Codes: B60W 2540/18 Steering angle
• CPC Class Codes: B60W 2720/14 Yaw
• CPC Class Codes: B60W 30/045 Improving turning performance
• CPC Class Codes: B62D 6/003 in order to control vehicle yaw movement, i.e. around a vertical axis B62D6/007 takes precedence
• CPC Class Codes: B62D 7/159 characterised by computing methods or stabilisation processes or systems, e.g. responding to yaw rate, lateral wind, load, road condition

Abstract

A turning behavior control device for vehicle has a left and right wheel driving force adjustment mechanism for adjusting a difference in driving force between rear wheels, a braking force adjustment mechanism for adjusting a difference in braking force between the wheels, a front wheel auxiliary steering mechanism for adjusting a steering angle of front wheels, a vehicle velocity sensor, a steering wheel sensor and a yaw rate sensor for detecting the behavior of a vehicle, and a control unit for controlling the front wheel auxiliary steering adjustment mechanism, the left and right wheel driving force adjustment mechanism and the braking force adjustment mechanism, based on the vehicle velocity, the steering angle and the yaw rate detected by the sensors. The control unit operates the front wheel auxiliary steering mechanism before operating at least one of the left and right wheel driving force adjustment mechanism and the braking force adjustment mechanism.

Claims

1. A turning behavior control device for a vehicle comprising:

a left and right wheel driving force adjustment unit that adjusts a difference in driving force between left and right wheels for the vehicle;

a steering angle adjustment unit that adjusts a steering angle for at least one of the front and rear wheels for the vehicle;

a vehicle behavior detection unit that detects the behavior of the vehicle; and

a control unit that controls the left and right wheel driving force adjustment unit and the steering angle adjustment unit, based on the vehicle behavior detected by the vehicle behavior detection unit;

wherein the control unit operates the steering angle adjustment unit before operating the left and right wheel driving force adjustment unit.

2. The turning behavior control device for vehicle according to claim 1, further comprising a braking force adjustment unit that adjusts a difference in braking force between each wheel for the vehicle, wherein the control unit controls the left and right wheel driving force adjustment unit, the braking force adjustment unit and the steering angle adjustment unit, based on the vehicle behavior detected by the vehicle behavior detection unit, and operates the steering angle adjustment unit before operating at least one of the left and right wheel driving force adjustment unit and the braking force adjustment unit.

3. The turning behavior control device for vehicle according to claim 2, wherein the control unit operates the steering angle adjustment unit, the left and right wheel driving force adjustment unit and the braking force adjustment unit in order as the vehicle behavior detected by the vehicle behavior detection unit becomes unstable.

4. The turning behavior control device for vehicle according to claim 2, wherein the control unit calculates a required yaw moment given to the vehicle, based on the vehicle behavior detected by the vehicle behavior detection unit, and operates the steering angle adjustment unit, the left and right wheel driving force adjustment unit and the braking force adjustment unit in order as the required yaw moment is greater.

5. The turning behavior control device for vehicle according to claim 4, wherein the control unit distributes the required yaw moment to the left and right wheel driving force adjustment unit, the braking force adjustment unit and the steering angle adjustment unit to operate them, in which the maximum distribution amount of required moment to the steering angle adjustment unit is smaller than the maximum distribution amount of required moment to the left and right wheel driving force adjustment unit and the maximum distribution amount of required moment to the braking force adjustment unit.

6. The turning behavior control device for vehicle according to claim 2, wherein the control unit operates at least one of the left and right wheel driving force adjustment unit and the braking force adjustment unit, and then decreases the operation amount of the steering angle adjustment unit.

7. The turning behavior control device for vehicle according to claim 2, wherein the vehicle behavior detection unit comprises a vehicle velocity detection unit that detects a vehicle velocity of the vehicle, a steering amount detection unit that detects a steering amount of the vehicle, a yaw rate detection unit that detects a yaw rate occurring in the vehicle, and a yaw rate deviation calculation unit that calculates a target yaw rate based on the vehicle velocity and the steering amount and calculates a difference between the target yaw rate and the yaw rate as a yaw rate deviation, and the control unit calculates a moment given to the vehicle, based on the yaw rate deviation detected by the yaw rate deviation calculation unit, and distributes the moment to the left and right wheel driving force adjustment unit, the braking force adjustment unit and the steering angle adjustment unit to operate them.

8. The turning behavior control device for vehicle according to claim 7, wherein the control unit operates the steering angle adjustment unit alone when the yaw rate deviation is less than a first threshold value, and increases the operation amount of the steering angle adjustment unit as the yaw rate deviation is greater.

9. The turning behavior control device for vehicle according to claim 7, wherein the control unit operates at least one of the left and right wheel driving force adjustment unit and the braking force adjustment unit when the yaw rate deviation is greater than or equal to the first threshold value, and decreases a contribution factor of the steering angle adjustment unit to the steering angle adjustment control as the yaw rate deviation is greater.

10. The turning behavior control device for vehicle according to claim 8, wherein the control unit makes the control amount of the steering angle adjustment unit constant when the yaw rate deviation is greater than or equal to the first threshold value.