Drowsy or drunk: Don't drive
Thursday, November 06, 2014 by Dr Trefor Morgan
The concept of a car, four wheels and an engine, has not changed for over 100 years. However, the technology and features found in each new generation of passenger vehicle are increasing rapidly. Features we now consider mundane: electric windows, air conditioning, indicators were all once novel ideas. There are many safety features such as seat belts, pre-tensioners, Alternative Fuel Electronics, Electronic Stability Control (ESC), airbags, curtain airbags, ABS, brake assistance and traction control that are, or are becoming, standard on modern production vehicles. Of course, none of these features matter if a driver falls asleep at 100kmph (60mph) and drifts into oncoming traffic.
Drowsy driver’s die – but how do we know when we are drowsy?
Many countries have national campaigns to reduce the number of accidents caused by driver fatigue or specifically the dangerous state of drowsiness. Campaigns such as the UK department of transport’s "Don't drive tired" campaign, serve to raise awareness of the dangers of drowsy driving. Despite these efforts, up to 30% of all accidents have fatigue as a contributing factor.
Determining fatigue levels
So how does someone self-determine if they are drowsy and are no longer fit to drive a vehicle?
Asking a drowsy person to subjectively assess their own level of drowsiness with respect to their ability to drive is like asking someone who has been drinking what they think their Blood Alcohol Content (BAC) would be.
A driver can become aware they are getting drowsy, by identifying signs such as yawning or wandering attention. This might lead them to open a window, turn on the air-conditioning or turn up the radio which may bring back their alertness for a while, but as the Australian TAC states "You can't fight sleep" and eventually this person will have a microsleep.
Whether it is alcohol or tiredness, the person under its effect is unable to make an objective determination on whether they are fit to drive.
This is where drowsiness detection systems in vehicles come to the fore. Systems based on measuring the lane deviation of a driver have been on the market for more than five years and are slowly finding their way into a larger range of production vehicles.
Daniel Levin, project manager for Driver Alert Control at Volvo Cars, commented about lane deviation technology in 20081:
"We often get questions about why we have chosen this concept instead of monitoring the driver's eyes. The answer is that we don't think that the technology of monitoring the driver's eyes is mature enough yet."
Optalert's technology uses the speed of a person’s blink to objectively determine the driver’s level of drowsiness. It has been demonstrated to work in the harsh and high risk environment of the mining industry since 2008 where the drivers of massive trucks can work long shifts over a number of weeks.
The future of fatigue management
In production cars, Optalert's technology is uniquely positioned to work with other fatigue management systems, as it can objectively measure the drowsiness level of a driver without the need for the driver to do any sort of active test. This measurement can be done continuously over the entire journey. Drivers can receive an early warning before their drowsiness level has risen to a stage where their chances of an accident has increased in the same way as if they had consumed alcohol above the legal limit.
So in the future, instead of having to wait to pass a sign saying “Drowsy Driver’s Die”, my car will objectively tell me how drowsy I am and warn me when I need to take a break.