A research project at the University of Leicester has combined eye-tracking and brain monitoring to calculate when a driver's alertness starts to wane.

To detect eye movements, researchers aim an array of LED lights at the subject's eyes. An infra-red camera sensor detectes the reflection of the lights off of the eyes.

According to the National Highway Traffic Safety Administration, there are more than 100,000 crashes, 40,000 injuries and 1,550 deaths a year in the United States as a result of drivers nodding off at the wheel.