ROAD SIGN ASSIST SYSTEM


  1. FUNCTION OF MAIN COMPONENTS


    1. The main components in the RSA have the following functions:

      Component Function
      Forward Recognition Camera (Camera Sensor) Monocular Camera Captures road signs.
      Forward Recognition Camera ECU Performs RSA system control based on information of road signs captured by the monocular camera.
      Camera Heater (Forward Recognition Hood) Heats the sheet heater in accordance with the signals from the forward recognition camera (camera sensor).
      Millimeter Wave Radar Sensor Assembly Sends preceding vehicle information to the forward recognition camera (camera sensor).
      Spiral Cable with Sensor Sub-assembly Steering Angle Sensor Detects the steering direction and angle of the steering wheel.
      Airbag Sensor Assembly Yawrate Sensor Sends yaw rate signals and the rate of deceleration and acceleration to the forward recognition camera (camera sensor).
      Speed Sensor Detects the wheel speed and transmits signals to the skid control ECU.
      Headlight Dimmer Switch Assembly Transmits a turn signal command to the combination meter assembly.
      Steering Pad Switch Assembly Sends a multi-information display operating signal to the combination meter assembly.
      Combination Meter Assembly Master Warning Light Illuminates when a system malfunction occurs.
      Multi-information Display

      • Displays road signs recognized by the forward recognition camera (camera sensor).

      • The RSA system can be turned on and off through the settings tab.
      Buzzer Sounds for speed limit exceeded, no overtaking and no entry notifications.
      Hybrid Vehicle Control ECU Sends a shift position signal to the forward recognition camera (camera sensor).
      Brake Booster with Master Cylinder Assembly Skid Control ECU Sends a vehicle speed signal from the speed sensor to the forward recognition camera (camera sensor).
      Main Body ECU (Multiplex Network Body ECU) Sends country specification information signals to the forward recognition camera (camera sensor).
      Air Conditioning Amplifier Assembly Sends the outside temperature signal to the forward recognition camera (camera sensor).
      Network Gateway ECU Relays and transmits each CAN communication data signal.

  2. FUNCTION


    1. The RSA system recognizes the following traffic signals using the forward recognition camera (camera sensor).

      Category Sign Type Example of Recognizable Traffic Sign
      Speed Limit Round Maximum Speed Limit/End of Speed Limit A001LXL
      No Overtaking No Overtaking/End of No Overtaking A001LP4
      Supplemental Signs Road Condition Signs Ramp Way A001LY7
      Rain A001LNO
      Ice A001LQX
      End of Prohibition A001LRE

    2. The RSA system recognizes the following traffic signals using the forward recognition camera (camera sensor).

      Category Display Example Details
      Speed Limit Related A001LUV

      • Informs the driver of the maximum speed limit of the currently driven road.

      • The displayed sign reflects the speed limit on the recognized sign.
      No Overtaking Related A001LL2 Informs the driver when they are in a no overtaking zone on the currently driven road.
      All Canceled (All restrictions canceled. Return to default road regulations.) A001LRE Informs the driver when all applicable prohibitions, such as speed limit and no overtaking, have ended.
      Speed Limit with Supplemental Sign Related Ramp Way A001LKB Informs the driver of the ramp way direction. However, this item is not displayed when making a lane change without operating the turn signal light.
      Rain A001LXI Informs the driver of the maximum speed limit on the currently driven road when it is raining or the road surface is wet.
      Ice A001LXV Informs the driver of the maximum speed limit on the currently driven road when there is accumulated snow or ice.
      Blank A001LUN The display is blank when the system is unable to recognize a supplemental sign.

    3. Notification functions are used in the RSA system which invert the colors of displayed signs, flash signs, etc. to notify the driver.


      1. Speed Limit Exceeded Notification


        • While a speed limit sign is displayed, if the actual vehicle speed exceeds the speed limit plus a designated threshold*, the colors of the displayed sign are inverted. For example, if the threshold is set to 5 km/h and the speed limit sign is 60 km/h, the colors of the displayed sign are inverted when the actual vehicle speed exceeds 65 km/h. Furthermore, the system also inverts a speed limit sign with supplemental sign in the same way. However, the system does not invert the colors of the supplemental sign.

        • The buzzer may be set to sound during notifications through the customization function. However, if a speed limit recognized from a speed limit with supplemental sign is exceeded, the buzzer does not sound.

        • This notification is judged according to the speed units estimated by the forward recognition camera (camera sensor). When moving to a region with different speed units, notifications may be incorrectly issued until learning is complete.

          Tech Tips

          *: The threshold can be adjusted to 1 of 3 levels through the customization function.

        Notification Method Display Example
        Inverted Display A001M3G

      2. No Overtaking Notification


        • While a no overtaking sign is displayed, if the system detects that the vehicle is attempting to overtake another vehicle, the system flashes the displayed sign.

        • The buzzer may be set to sound during notifications through the customization function.

        Notification Method Display Example
        Flashing Display A001LMH

    4. The RSA can be turned on or off through the settings tab of the multi-information display.

    5. A customization function is used for the RSA, which allows settings such as the notification method and level for exceeding the speed limit to be changed. Setting changes are made through the customization tab of the multi-information display.

      A001LXRC01
      *a Vehicle Settings Tab *b The illustration shown is an example only.

  3. SYSTEM CONTROL


    1. RSA Control Pattern 1


      1. After a road sign is recognized by the forward recognition camera (camera sensor) and the vehicle passes by, the sign is displayed on the multi-information display.

      2. While a sign is displayed on the multi-information display, if a new road sign is not recognized within a specified distance, display of the current sign is turned off.

        A001LNME02
        *1 Road Sign Recognized
        *2 Specified Distance Driven
        *3 Sign Display Off
        *4 Sign Display On

    2. RSA Control Pattern 2


      1. When the power switch is turned off while a sign is displayed on the multi-information display, the same sign is displayed when the power switch is turned on (IG) again.

        A001M08E08
        *1 Power switch is turned off.
        *2 Power Switch is turned on (IG)
        *3 Sign Display On

    3. RSA Control Pattern 3


      1. While a sign is displayed on the multi-information display, the sign is turned off when turning left or right onto a new road.

        A001M0RE02
        *1 Road Sign Recognized
        *2 Sign Display Off
        *3 Sign Display On

  4. DIAGNOSIS


    1. If a malfunction is detected in the RSA, the forward recognition camera (camera sensor) cancels the RSA, sounds the buzzer in the combination meter assembly, and displays a message on the multi-information display to inform the driver of the malfunction.

    2. At the same time, the malfunction is stored in memory as a Diagnostic Trouble Code (DTC). When a Global TechStream (GTS) is connected to the DLC3, the DTC can be read. For details, refer to the Repair Manual.