BRAKE CONTROL SYSTEM


  1. SYSTEM CONTROL


    1. The VSC and Cooperative Control with EPS*1 or VSC+*2 is used.

      *1: Models for general countries

      *2: Models for Europe


      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 assembly 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.

        A01O708C03
        *a Slippery Surface - -
        B008JPG Brake Force B008JPP Assist Direction
        A01O71O 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 assembly causes the TRC to control the hydraulic brake of the slipping drive wheel, and requests the hybrid vehicle control ECU assembly 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.

        A01O7IFC01
        *a Slippery Surface - -
        B008JPG Drive Force B008JPP Assist Direction
        A01O71O Yaw Moment During Acceleration - -

      3. When the skid control ECU assembly 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)

        A01O766C01
        *a Front Wheel Skid Tendency - -
        B008JPG Brake Force B008JPP Assist Direction to Indicate Front Wheel Skid
        A01O71O Assist Direction to Counter Excessive Steering Input A01O7CF Control Moment

      5. When the skid control ECU assembly 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.

        A01O76ZC02
        *a Rear Wheel Skid Tendency - -
        B008JPG Brake Force B008JPP Assisting Direction
        A01O7CF Control Moment - -