This device allows maximum ease of manoeuvring during parking;
with reverse gear engaged, it indicates if the driver is approaching
an obstacle that could be outside his field of vision, as illustrated
in the diagram below. The system operates in accordance with the
ultrasound 'sonar' principle: four ultrasound transducers are located
in the rear bumper. They send signals to a control unit, which processes
this information and determines the distance of possible obstacles. A loudspeaker controlled by the control
unit emits an intermittent tone, proportional to the distance of
the obstacle detected. The control unit is activated when reverse
gear is engaged: under these conditions it energizes the transducers
and sends them a signal request, and receives response signals from them. Via the specific loudspeaker, the control
unit emits a signal with an intermittent tone: this sound increases
in frequency as the bumper comes closer to an obstacle.If the distance measured from the obstacle
increases, or if the driver disengages reverse gear, the sound stops.
If the distance measured from the obstacle remains constant, the sound
ceases after about 3 seconds. The signal that the reversing light has
been switched on is managed by the Body Computer node which forwards
this information to the parking sensor control unit via the CAN
network.