, Director, Mechanical Engineering
Fatigue has a known influence on negatively affecting driving safety (e.g., increased microsleeping, falling asleep at the wheel, lane drifting) but has been difficult to detect and identify. As such, there is a need to develop an objective and reliable roadside tool to detect driver fatigue. The purpose of this project was to validate a series of assessment tests, including--but not limited to--the critical flicker frequency (CFF), Brief Psychomotor Vigilance Test (PVT-B), and Trail Making Test, to determine their ability to reliably measure level of alertness or fatigue, as an objective tool to assess driver fatigue. Researchers conducted a large sample fatigue study to identify the rate and public acceptance of drowsy driving and establish normative data sets for select fatigue assessment measures among the general Minnesota population. Following, a 30-hour sleep deprivation study assessed driving performance and fatigue under alert to extreme fatigue conditions. Results from the large sample fatigue study demonstrated a positive relationship between CFF threshold, age, gender, and elapsed sleep measures. Results from the sleep deprivation study showed prolonged wakefulness influenced driving performance (i.e. sleepiness at the wheel) and a relationship between impaired driving and cognitive test performance. A cognitive composite measure of the PVT-B and Trail Making Test predicted fatigue-related driving outcome variables, suggesting these tests may be useful for further development and assessment of roadside measurement fatigue.