Introduction - Driver Drowsiness Detection: Systems and Solutions - page 2

Fig. 1.1 Proportion of road traffic deaths by age range

drowsiness in the corresponding Police Crash Reports (PCR). Additionally, many
other accident reports referred to “Drift-Out-Of-Lane” crashes, which might be
related to drowsiness aspects as well. Approximately 71,000 of all drowsy-related
crashes involved non-fatal injuries, whereas 1,357 drowsy-related fatal crashes
resulted in 1,544 fatalities (3.6 % of all fatal crashes), as reported by the Fatality
Analysis Reporting System (FARS). Nevertheless, many run-off-roadway crashes
are not reported or cannot be verified by police, suggesting that the problem is much
larger than previously estimated.
A significant number of surveys, studies and reports suggest that drowsiness is
one of the biggest causes of road accidents. The US National Sleep Foundation
(NSF) reported that 54 % of adult drivers have driven a vehicle while feeling drowsy
and 28 % of them actually fell asleep on the wheel [ 6 ]. Powell et al. [ 9 ] concluded
that sleepiness can impair driving performance as much or more than alcohol.
A more recent report [ 13 ] from The American Automobile Association (AAA)
estimates that one out of every six (16.5 %) deadly traffic accidents, and one out
of eight (12.5 %) crashes requiring hospitalization of car drivers or passengers is
due to drowsy driving. In summary, there is a substantial amount of evidence that
suggests that drowsiness is one of the big factors in road accidents.

1.2 What Is Drowsiness?

Drowsiness ,alsoreferredtoas sleepiness , can be defined as “the need to fall asleep”.
This process is a result of normal human biological rhythm, which consists of sleep-
wake cycles. The sleep-wake cycle is governed by both homeostatic and circadian
factors. Homeostasis relates to the neurobiological need to sleep; the longer the