Cars That Won’t Let You Sleep!

By Ayushi Pradhan

News Event: Article: New Cars Won’t Let You Sleep! By Shweta Dhadiwal Under Automobiles from Electronics For You Issue March 2010.

Mercedes-Benz E-Class- innovative and intelligent electronic system, Attention Assist, detects drowsiness and alerts the driver to take a break when they feel sleepy while driving.

The new cars are full of sensors that help in input to the custom Attention-Assist software. The sensors provide the system with data on acceleration, how the wheel is being turned and whether turn signals are being used. The software then compares the driver’s interaction with the car to a database of examples of sleepy driver behaviour that Mercedes researchers have collected.

A development in sensor technology and info processing- this smart electronic system detects the drowsiness of the driver well in advance and alerts him immediately. Many designers have come up with several techniques to detect drowsiness and warn the driver through an audio/visual system.

Detection of drowsiness: Nodding of head Closing of eyes Changes in steering behaviour Pedal pressure

However these changes can be possible under normal circumstances i.e. non-drowsiness conditions as well.

An intelligently designed system that could monitor a combination of parameters can be really assuring for the car occupants.

Blinking of eyelids Monitoring of the lane keeping performance

Drowsy drivers make more minor errors, which they correct with abrupt and rapid ways.

Quick and abrupt corrections are recognised by highly sensitive steering-angle sensor.

To identify the point where the driver slips into weariness from an alertness, the engineers at Mercedes fitted many test drivers with brainwave monitoring skull caps to obtain their electroencephalograms (EEG).

Steering wheel sensor

The quality of drowsiness detection is highly dependent on how accurate the parameters are acquired and analysed.

Attention Assist Standard equipment part in E-class ->uses

several highly sensitive sensors. They continuously monitor more than 70

different parameters External influences such as wind and road

irregularities are also taken into consideration Vehicle speed, lateral acceleration and

longitudinal acceleration

Data acquisition and processing

Attention Assist Based on data acquired by sensors, AA identifies

the driver’s driving profile in the first few minutes of every trip.

This profile is then compared by the car’s electronic control unit, with the current sensor data and prevailing driving situation

This is needed to detect floating transition from awakeness to drowsiness and for giving timely warning to the driver

When the warning threshold is reached, or an unusual behaviour detected, the system triggers an acoustic warning signal and a text message is displayed in the instrument cluster ( AA pause & coffee mug symbol)

Working Conditions The system is active at a speed of 80-180 kmph It creates the drivers profile through analysis and

classification of his steering and driving behaviour in order to determine the individual warning threshold.

A complete profile is typically formed in 20-30 min depending on the road and traffic conditions.

You cannot save a driver’s profile because it may vary.  The system works positively on highways and expressways in

Western countries. For India, the average speed on highways in different states

varies from 65-90 kmph.only some expressways have speed limits of 100-120 kmph.

So the system is inactive for most of the drive time in India It is not difficult for the system to be customised but the

feasibility has not been determined yet.

Thus this question ponders as to how attention assist can be used in India if it is active only at 80-180 kmph...

Area of impact

Health Science

Issues Costly- brand name -new technology Cannot possibly used everywhere in the

world due to limited speed reactions Computer system- so not possible to

differentiate between several changes which could be possible parameters

Manufacturers-Mercedes Customers-Public Researchers/Scientists

Stakeholders

Machinery for manufacturing the car Attention Assist Software Raw materials( metals, wires, plastics etc)

IT components