BRAKE CONTROL SYSTEM


  1. SYSTEM CONTROL


    1. If the driver suddenly applies the brakes on a road surface with a considerable difference in friction coefficient between the right and left wheels, the difference in the brake force between the right and left wheels will cause the vehicle posture to become unstable and create a yaw moment. In this state, the skid control ECU controls the ABS and VSC to stabilize the vehicle posture. At the same time, it effects cooperative control with the EPS to provide steering torque assist, which facilitates the driver's steering maneuvers to stabilize the vehicle posture.

      A00YZZFC02
      *a Slippery Surface - -
      A00Z06S Brake Force A00Z09V Assisting Direction
      A00Z00N Yaw Moment During Brake Controlling - -

    2. If the driver suddenly starts off or accelerates on a road surface with a considerable difference in friction coefficient between the right and left wheels, the slippage of a drive wheel will cause the vehicle posture to become unstable and negatively affect its acceleration performance. In this state, the skid control ECU causes the TRC to control the hydraulic brake of the slipping drive wheel, and requests the power management control ECU to effect motive force control. At the same time, it effects cooperative control with the EPS to provide steering torque assist, which facilitates the driver's steering maneuvers to stabilize the vehicle posture.

      A00Z0DVC02
      *a Slippery Surface - -
      A00Z06S Drive Force A00Z09V Assisting Direction
      A00Z00N Yaw Moment During Accelerating - -

    3. When the skid control ECU determines a front wheel skid tendency, it controls the VSC to dampen the front wheel skid. At the same time, it effects the cooperative control with the EPS to provide steering torque assist, which controls the driver's steering maneuvers to stabilize the vehicle posture. Steering torque assists are provided to inform the driver of the front wheel skid, and to prevent the driver's excessive turning of the steering wheel. In the assist for preventing excessive turning, it increases the resistance to counter the driver's steering effort, if the driver turns the steering wheel excessively.

      A00Z0BOC01
      *a Front Wheel Skid Tendency - -
      A00Z06S Brake Force A00Z09V Assisting Direction for Information of Front Wheel Skid
      A00Z00N Assisting Direction for Preventing Excessive Turning A00Z09X Control Moment

    4. When the skid control ECU determines a rear wheel skid tendency, it controls the VSC to dampen the rear wheel skid. At the same time, it effects the cooperative control with the EPS to provide steering torque assist, which facilitates the driver's steering maneuvers in the direction to correct the rear wheel skid.

      A00Z06PC01
      *a Rear Wheel Skid Tendency - -
      A00Z06S Brake Force A00Z09V Assisting Direction
      A00Z09X Control Moment - -