Fatigue and/or drowsiness m primary causes of serious trafic accidents, therefore evaluation of car drivers' condition and early warning, especially by automatic wearable systems, are highly important. In order to design such systems, identification of indicators of drivers' fatigue / drowsiness is necessary. We focused on bio-signals, and built a driving simulator with bio-signal evaluation equipment. From the results of experiment we found changes in frequency of eye movement (an increase in low frequency) are meaningful as an indicator.
