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In the 2007 model year, Toyota unveiled the first driver monitoring system in the
world on the Lexus LS. The system monitors the driver and if driver's head turns
away from the road and a frontal obstacle is detected, the system will warn the driver
by sound and, if necessary, tighten the safety belts and precharge the brakes. Driver
monitoring system released in 2008 added the ability to detect the driver's level of
alertness by monitoring the driver's eyes. The system was designed to function even
in challenging situations if the driver is wearing sunglasses or at night.
Emerging ADAS Functions
Emerging applications such as mirror replacement camera bring several advantages
over conventional mirrors. The advantages include vehicle weight reduction result-
ing in lower fuel consumption and CO 2 emissions, greater freedom in car design,
savings onmirror adjustment switches andmotors, and removal of the blind spot. The
camera monitor systems (CMS) also open potential path for inclusion of embedded
vision analytics features. Standardization of CMS is ongoing under ISO16505 with
participation of all European OEMs.
3.3.1 Front View Camera Systems
At the simplest level, front view camera system offers intelligent AFS. The intelli-
gent AFS can adjust the vehicle headlights according to ambient light level or it can
detect presence of oncoming vehicles and turn the vehicle's main beams on and off
appropriately at night.
At the next level of processor performance, the front view camera system can
also detect road lanes and provide functions such as lane departure warning or lane
keep assist. This is typically mono camera system shown in left panel of Fig. 3.2 .
The embedded processor (the number cruncher) receives high dynamic range video
input from a megapixel imaging sensor at 30 frames per second.
The systemrelies on vehicleCANbus to receive information such as vehicle speed,
steering wheel angle, yaw rate, etc., and to send output which can be either warning
to the driver or control command to steering/braking subsystems. The processor
connects to the vehicle CAN bus via the external microcontroller (MCU). The MCU
in the system typically conforms to high level of functional safety.
Further increase in the processor compute power enables functions such as pedes-
trian detection, FCW, and TSR. Strong interest in TSR in Europe is driven by diffi-
culty for drivers to keep track of the actual speed limit in effect—as some European
countries adopted variable speed limits that change at various time of the day or night
in order to reduce traffic noise or improve safety at busy intersections.
Vision-based object detection and classification is a key problem in driver assis-
tance. Functions such as detection and classification of objects (i.e., cars, motorcy-
cles, and trucks) and pedestrians require substantial compute power. Adding second
imaging sensor to the front camera system improves detection reliability since dense
stereo can provide additional cues for pedestrian recognition. The depth information
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