30 July 2009

Tired drivers can get yawn alert

After long hours behind the wheel, you can just feel the eyelids starting to get heavy, you feel a deep yawn coming on, and your neck muscles relax. You just want to sleep. But, your hands are still on the wheel, and you only just stopped yourself nodding off in time to avoid the oncoming traffic—a scary moment.

There will soon be a technology that will allow your car to keep an eye on you while you drive and nudge you when you starting yawning and warn you to pull over and take a break. That is the aim of a new in-car yawn-detection system under development by a team in the U.S. and India.

There is now a computer program that can tell when you are yawning and could prevent road traffic accidents, according to Aurobinda Mishra of Vanderbilt University, in Nashville, Tenn., and his colleagues Mihir Mohanty of ITER, in Orissa and Aurobinda Routray of IIT, West Bengal, India.

The U.S. National Highway Traffic Safety Administration estimates at least 100,000 road crashes each year are the result of driver fatigue.

The new program centers on an in-car camera hooked up to image-processing software that captures a sequence of images of the driver’s face. It then analyzes changes in the face and accurately identifies yawning as distinct from other facial movements such as smiling, talking, and singing. The yawn frequency then correlates with fatigue behavior and could then kick off the warning system to alert drivers they need to take a break.

The algorithm is effective at yawn detection regardless of image intensity and contrast, small head movements, viewing angle, spectacle wearing, and skin color.

The researchers point out for traffic safety, it is essential to recognize and understand the physical and mental stress leading to fatigue in drivers. Considerable research occurred to investigate and characterize biological signals, such as brain waves and heart activity.

However, it would be costly and inconvenient for drivers to have to connect to an ECG machine every time they took a trip. A system that watches the driver and analyses their facial expressions would be much simpler and less invasive.

For related information, go to www.isa.org/sensors.