An ANALYSIS of SACCADIC EYE MOVEMENT Using FFT for ASSESSING VIGILANCE LEVELS during SIMULATED DRIVING

摘要

Frequency characteristics of accelerative waveform of saccadic eye movement (saccade: SC)were focused as a candidate for a vigilance index and were discussed in connection withchange in visually rated facial sleepiness (FS). An experiment of one-hour simulated drivingwas conducted for nine subjects, and eye movement and facial video image were recorded. Apower spectrum of the accelerative waveform was calculated for each SC using fast Fouriertransform (FFT). FS was rated in five levels for every five seconds of the recorded facialvideo by two trained determiners. As a result, the spectral power within 0-3 or 10-40 Hzindicated higher correlation with FS than previously proposed vigilance index (PV/D) in sixof nine subjects. Since the frequency at which the spectral power showed the highest absolutecorrelation varied with subject, the necessity for contriving additional processing to derivemore sensitive and common vigilance index was confirmed.