Driver sleepiness contributes to a great number of motor vehicle accidents every year. In order to reduce the number of sleepiness related accidents, more knowledge on driver behaviour is needed. Data from field operational tests (FOT) has a potential to provide such knowledge. The objective of this project was to propose and evaluate methods for identification of driver sleepiness. The aim was to identify objective indicators of sleepiness – based on driving behaviour, eye blink behaviour and models of circadian rhythm – and to evaluate a subjective video scoring method for estimating driver sleepiness levels. The results show that studying driver sleepiness in (existing) FOT data is difficult, for several reasons: 1) eye camera based indicators suffer from detection errors and low detection rate, 2) driving-based indicators are influenced by e.g. road curvature and traffic density, 3) models of sleepiness cannot be used since no information on hours slept and time awake is available, and 4) video scoring is not reliable, at least not given the quality of the available video recordings. In a first step the data quality of blink-based indicators obtained from a camera system was evaluated. It was concluded that the data quality had to be improved and thus, a new detection algorithm was devised and implemented. An in-depth study on indicators of driver sleepiness was carried out using data collected in the SleepEYE experiment (see ViP publication 2011-6), with the purpose of employing the best indicators to study driver sleepiness in the euroFOT database. The most promising indicators were found to be mean blink duration and number of line crossings. A study was carried out on whether it is possible to use video recordings of drivers in order to estimate the drivers’ self-rated level of sleepiness. The results of the study showed that performing such observer rated sleepiness (ORS) estimations on drivers is extremely difficult. The videos available in FOTs are usually of rather poor quality which, clearly limits the possibility of making reliable observer rated sleepiness estimations. The reported work was carried out in a collaborative project within the ViP competence centre (www.vipsimulation.se). (Author/publisher) This report may be accessed by Internet users at http://www.vti.se/en/publications/investigation-of-driver-sleepiness-in…
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