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.

      B002326C01
      B0082XT Brake Force B0082R6 Assist Direction
      B0022W1 Yaw Moment During Brake Controlling B00831B Slippery Surface

    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. 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.

      B0023EIC01
      B0082XT Drive Force B0082R6 Assist Direction
      B0022W1 Yaw Moment During Accelerating B00831B Slippery Surface

    3. When the skid control ECU determines that front wheel skid is occurring, it controls the VSC to dampen the front wheel skid. At the same time, it performs cooperative control with the EPS to provide steering torque assist, which helps the driver control the driver's steering maneuvers used to stabilize the vehicle posture.

    4. Steering torque assist provides the following functions.


      1. Steering torque assist is used to inform the driver of a front wheel skid: (a)

      2. If the driver turns the steering wheel excessively, steering torque assist provides assistance to counter the excessive steering input: (b)

        B0022YTC01
        *a Front Wheel Skid Tendency - -
        B0082XT Brake Force B0082R6 Assist Direction to Indicate Front Wheel Skid
        B0022W1 Assist Direction to Counter Excessive Steering Input B0023JF Control Moment

    5. 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 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.

      B0023AVC01
      *a Rear Wheel Skid Tendency - -
      B0082XT Brake Force B0082R6 Assisting Direction
      B0023JF Control Moment - -