Dokument 1.pdf - ELBA: Das elektronische BASt-Archiv - hbz

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Assessment of driver fatigue
Driver fatigue is a contributing factor in an
estimated 10-20% of road accidents. A huge
number of different methods is available to assess
driver fatigue. The project’s goal was to describe
and compare the strengths and weaknesses of
different methods to assess driver fatigue and to
present an overview of the existing fatigue
detection and fatigue warning systems. The
evaluation of these methods and systems is based
on literature analysis and interviews with experts
and users. The following procedures were taken:
• Literature analysis and overview of physiological
and performance-based methods to assess
driver fatigue.
• Literature analysis of fatigue detection and
warning systems, interviews with their
manufacturers and overview of the identified
systems.
• Interviews with 20 users of currently in middleand
upper-class cars implemented fatigue
warning systems to assess the perceived quality
of fatigue detection, driver acceptance and
compliance.
• Development of a list of criteria to assess and
compare the quality of the most valid methods to
assess driver fatigue.
• Two-stage survey (Delphi-Study) with 12
experts from academic and industrial research
areas. It was aimed at the selection and
evaluation of the most valid methods to assess
driver fatigue, their subsequent re-evaluation
providing explanatory statements in case of
contradicting opinions, and the assessment of
the methods’ suitability for different fields of
application.
users’ point of view. Several drivers continue to
drive even despite of a system’s warning that they
perceive as accurate. About half of them perceive
fatigue warning systems as a gain in safety.
The most valid methods to assess driver fatigue
selected by the 12 experts are the assessment of
driving performance (steering behaviour and lane
keeping) and eyelid closure, video-based expert
assessments, EEG and (quite controversial) the
Pupillographic Sleepiness Test. Their differing
strengths and weaknesses are extensively
described in the report at hand.
There is still no gold standard of fatigue
assessment. Depending on the fields of application
all six of the selected methods (research &
development), only a few (fatigue warning systems)
or none of them (traffic controls) are applicable.
When choosing a method the goal and context of
fatigue assessment and the strengths and
weaknesses of the respective methods should be
considered. The combination of at least two
different methods is recommended to achieve a
valid assessment of driver fatigue.
Fatigue detection systems and the most promising
methods to assess driver fatigue should be further
optimized and accompanying studies need to be
conducted. Further measures to effectively reduce
the number of accidents were discussed during the
workshop and presented in the report at hand.
• Workshop with the experts that participated in
the Delphi-Study to discuss and complement the
obtained results.
70 fatigue detection systems were identified. They
differ in their underlying methods to assess fatigue,
their availability and design of driver feedback, and
in their prevalence. Convincing evidence of their
validity or the percentage of false and missed
alarms are rarely reported. The fatigue warning
systems that are more and more implemented in
middle- and upper-class cars often fail to provide a
satisfying fatigue detection performance from a