Operator fatigue estimation using heart rate measures

The growing number of fatigue related accidents in recent years has become a serious concern. Accidents caused by fatigue in transportation and in mining operations involving heavy equipment can lead to substantial damage and loss of human life. Preventing such fatigue related accidents is highly desirable, but requires techniques for continuously estimating and predicting the operator’s alertness state. This paper proposes ECG-based operator fatigue estimation. For this aim, ECG was recorded continuously, and several heart rate measures were calculated and correlated with other well established fatigue labels. As a result, changes in operator’s fatigue during a night time study could be depicted during three different conditions. In the first condition, subjective and objective fatigue measures were collected during a 40-minute monotonous driving task. In the second and third condition, a 10-minute Compensatory Tracking Task (CTT) and a 5-minute Psychomotoric Vigilance Test (PVT), respectively, delivered a set of additional objective fatigue measures. Correlations between heart rate and fatigue measures were calculated, using experimental results of two volunteers, who each completed two nights in a real-car lab following a partial sleep deprivation design. The subjects were going through all three conditions (driving, CTT and PVT) eight times during the course of one night.