Characterization of the effects of vibration on seated driver alertness

Abstract

Although performance of vehicle drivers under fatigue conditions has been investigated in many types of environments, there is insu cient research data about the e ects of vibration speci cally on levels of mental alertness in seated drivers. In addition to the paucity of research in this area, the study of drowsiness caused by whole body vibration is complex due to several confounding factors (such as lack of sleep, air temperature, health). Hence, we investigated the relationship between whole body vibration and driver drowsiness. A human vibration test setup was designed for this study. Ten subjects were exposed to low frequency sinusoidal and random whole body vibration in multi-axial vibration at 0.3 m/s² (rms) for 20 minutes. Changes in drowsiness during vibration exposure were measured by recording electroencephalographic signals. Two brainwave spectrums (theta and beta waves) were used for analysis. Exposure to whole body vibration was found to be correlated with a reduction in alertness. Reduction in beta wave and increase in theta wave activity, caused by vibration, were found to be statistically signi cant. The data presented here quantify for the rst time the drowsiness caused by whole body vibration and will help de ne the threshold limit for safe driving.

The combined fatigue effects of sequential exposure to seated whole body vibration and physical, mental, or concurrent work demands

“…at 10 Hz) led to a decrease in the Alpha Attenuation Coefficient (AAC), which is associated with low wakefulness. In another study, based on recordings of Beta and Theta brainwave spectrums, Azizan and colleagues (2014) [ 51 ] found decreases in beta wave activity during both low frequency random and sinusoidal WBV at 0.3m/s 2 for 20 minutes. A decrease in Beta wave activity was more pronounced during the sinusoidal condition, which implies a greater drowsiness effect during sinusoidal compared to random WBV.…”