Vehicle turning behavior control apparatus

• US 5,267,783 A
• Filed: 03/22/1991
• Issued: 12/07/1993
• Est. Priority Date: 03/27/1990
• Status: Expired due to Fees

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Inoue, Shunichi, Matsumoto, Shinji, Inoue, Hideaki, Murakami, Hideto, Hano, Sunao, Yamaguchi, Hirotsugu
• Primary Examiner(s): Graham, Matthew C.
• Application Number:
  US07/673,300
• Time in Patent Office: 991 Days
• Field of Search: 303/100, 303/111, 303/173 AD, 303/9.62, 303/303, 303/113.5
• US Class Current: 303/146
• CPC Class Codes: B60T 2270/313 with less than three sensors (yaw rate, steering angle, lateral acceleration)
• 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: B60T 8/246 Change of direction
• CPC Class Codes: B60T 8/4013 Fluid pressurising means for more than one fluid circuit, e.g. separate pump units used for hydraulic booster and anti-lock braking
• CPC Class Codes: B60T 8/4275 Pump-back systems
• CPC Class Codes: B62D 6/04 responsive only to forces disturbing the intended course of the vehicle, e.g. forces acting transversely to the direction of vehicle travel

Abstract

A vehicle turning behavior control apparatus for use with a multi-wheel automatic vehicle. The apparatus provides a difference between the braking forces applied to the nearside and offside wheels of the vehicle to produce a yaw moment in a direction to which the vehicle turns. The difference is determined based upon the vehicle steering angle and is modified based upon the vehicle steering speed.

Claims

1. An apparatus for controlling turning behavior of a multi-wheeled automotive vehicle supported on a plurality of pairs of wheels, the apparatus comprising:

braking means for applying braking forces to the respective wheels;

first sensor means sensitive to a vehicle steering angle for producing a first signal indicative of a sensed vehicle steering angle;

second sensor means sensitive to a vehicle steering speed for producing a second signal indicative of a sensed vehicle steering speed; and

a control unit coupled to the first and second sensor means, the control unit including,

means for calculating a basic value Δ

P1 as a function of the sensed vehicle steering angle to increase the basic value as the sensed vehicle steering angle increases when the sensed vehicle steering angle increases when the sensed vehicle steering angle exceeds a predetermined value,

means for calculating a first correction factor K1 as a function of the sensed vehicle steering speed and to increase the first correction factor as the sensed vehicle steering speed increases,

means for calculating a second correction factor K2 as a function of vehicle speed and to decrease the second correction factor as the vehicle speed increases,

means for calculating the difference Δ

P as Δ

P=Δ

P1×

K1×

K2, thereby reducing the difference Δ

P between the nearside and offside wheels as the vehicle speed increases, and

means for setting the braking means to provide the calculated difference Δ

P between the braking forces applied to nearside and offside wheels of at least one of the pairs of wheels so that the braking force applied to the offside wheel is smaller than the braking force applied to the nearside wheel.

2. The apparatus as claimed in claim 1, further comprising third sensor means associated with a brake pedal of the vehicle for producing a third signal when the brake pedal is depressed, and wherein the control unit includes means responsive to the third signal for causing the braking means to set the braking force applied to the nearside wheel at a first value corresponding to an amount the brake pedal is depressed and the braking force applied to the offside wheel at a second value equal to the first value minus the calculated difference.

3. The apparatus as claimed in claim 2, wherein the braking means includes automatic braking means operable for applying constant braking forces to the respective wheels when the sensed vehicle steering angle exceeds a predetermined value, and wherein the control unit includes means operable, when the automatic braking means is operating, for causing the braking means to set the braking force applied to the offside wheel to zero and the braking force applied to the nearside wheel at a value equal to the calculated difference.