Abstract: In a brake control system for yaw control in a vehicle, the conditions for starting a brake operation are that the absolute value of a deviation between a target yaw rate determined in a target yaw rate determining device and an actual yaw rate detected by a yaw rate detecting device is equal to or greater than a preset deviation value and that the absolute yaw rate is equal to or greater than a preset value. The wheel brake for an outer wheel, during turning of the vehicle, is operated by the yaw control system based on the deviation between both the yaw rates. However, brake control does not occur when both of the yaw rates are the same in direction and are large. Thus, yaw control is conducted immediately when necessary, but the conduction of unnecessary yaw control is avoided, thereby reducing the frequency of the brake operation.
Abstract: Apparatus for improving the driving behavior of a vehicle is provided. The vehicle has front and rear axles, each having a plurality of wheels. Each wheel-has a brake. Sensor are provided for measuring the rotational speed of each wheel, the vehicle yaw rate and the vehicle lateral acceleration. An anti-lock braking system provides first preset pressure values for controlling each brake, to prevent the wheels from locking during braking. A traction slip control system provides second preset pressure values for controlling each brake, to prevent the wheels from slipping during acceleration. A brake effort proportioning system provides third preset pressure values for distributing braking pressure between the wheels of the front axle and the wheels of the rear axle. A yawing moment controller provides fourth preset pressure values used to control each brake during cornering, to avoid application to the vehicle of an unbalanced moment which would cause the vehicle to understeer or oversteer.
Type:
Grant
Filed:
November 24, 1997
Date of Patent:
January 19, 1999
Assignee:
ITT Automotive Europe GmbH
Inventors:
Alfred Eckert, Benno Lammen, Peter Wanke, Karl-Friedrick Worsdorfer, Thomas Geiger, Johannes Graber, Stefan Drumm, Thomas Kranz, C. Jan Neederkorn
Abstract: A traction control system and method of a four-wheel drive vehicle comprises an engine control apparatus, a brake drive apparatus for automatically and independently applying brake to each of four wheels, wheel speed detecting means, vehicle speed detecting means, steering angle detecting means, yaw rate detecting means, target yaw rate calculating means, yaw rate deviation calculating means, slip amount calculating means for calculating an actual slip amount, reference slip amount storing means for memorizing a reference slip amount, target slip amount determining means for determining a target slip amount based on the reference slip amount, traction control judging means for outputting a traction control signal when a traction control is needed, target braking force calculating means, target engine torque calculating means. When a traction control is needed, the target slip amount determining means determine a target slip amount of a wheel needing the traction control.
Type:
Grant
Filed:
September 6, 1996
Date of Patent:
December 15, 1998
Assignee:
Fuji Jukogyo Kabushiki Kaisha
Inventors:
Koji Matsuno, Yutaka Hiwatashi, Akira Takahashi, Munenori Matsuura
Abstract: Apparatus for improving the driving behavior of a vehicle is provided. The vehicle has front and rear axles, each having a plurality of wheels. Each wheel has a brake. Sensor are provided for measuring the rotational speed of each wheel, the vehicle yaw rate and the vehicle lateral acceleration. An anti-lock braking system provides first preset pressure values for controlling each brake, to prevent the wheels from locking during braking. A traction slip control system provides second preset pressure values for controlling each brake, to prevent the wheels from slipping during acceleration. A brake effort proportioning system provides third preset pressure values for distributing braking pressure between the wheels of the front axle and the wheels of the rear axle. A yawing moment controller provides fourth preset pressure values used to control each brake during cornering, to avoid application to the vehicle of an unbalanced moment which would cause the vehicle to understeer or oversteer.
Abstract: Apparatus for controlling an automotive vehicle is provided. The vehicle has a plurality of wheels, each wheel having an individually operable brake. The apparatus comprises a mechanism for determining the steering angle of the vehicle. A yawing moment controller receives the steering angle and determines a moment that is applied to the vehicle to prevent an undesirable yaw angle, yaw rate or yaw acceleration. Distribution logic receives the output of the yawing moment controller. The distribution logic determines a respectively different weighted coefficient for each individual brake, and an individual braking pressure to be applied to each respective one of the brakes based on the moment and the respective weighted coefficient of the one brake.
Abstract: A method for controlling the brakes in an automotive vehicle. The vehicle has a velocity and a plurality of wheels, each wheel having an angular velocity and a brake which is operable by applying a pressure agent to the brake. An amount of the pressure agent to be applied to, or released from, each brake, individually, to implement a desired braking operation is determined. Switching times corresponding to the amounts of the pressure agent are calculated for opening and closing the inlet valve or outlet valve of each respective brake, individually. An estimated vehicle velocity and an estimated wheel angular velocity which result from applying the pressure agent to the brakes are determined. The actual velocity of the vehicle and the actual angular velocity of the wheels are determined by measuring the angular velocity, and determining the velocity based on the measurement.