Mercedes calls it the “one second nap”. That brief moment where you almost fall asleep behind the wheel but catch yourself in time. Now Mercedes says it has the technology to detect this state of tiredness, and will warn the driver before he/she has can cause an accident.

Studies show that overtired drivers are a contributing factor in 25 percent of serious accidents. According to Mercedes, after four hours of continuous driving, it takes a driver double the time to react to a situation. After six hours, this fatigue rate raises to eight times higher than normal.

To combat this Mercedes will begin to make a system called Attention Assist available on its cars in spring of 2009. Attention Assist compiles information about the driver in the first few minutes of a journey using acceleration, steering and external environment data. This profile is used as a constant comparison for the rest of the trip. At any point if the electric system detects fatigue, it may use warring noises and also display advise such as, "Attention Assist. Break!"

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