Fatigue Among Indonesian Commercial Vehicle Drivers: A Study Examining Changes in Subjective Responses and Ocular Indicators

Abstract

Fatigue from driving is a risk factor in many road traffic accidents and the association between task duration and fatigue, in particular, has been a subject of research interest. Fatigue (and sleepiness) seems to plague many Indonesian commercial drivers whose jobs involve long-duration driving, but this issue is still rarely quantified and investigated. This study aims to characterize fatigue from long-duration driving, with a special interest in the use of eye-blink indicators. A total of 12 male commercial drivers participated in this study, in which they had to drive for about two sessions of 2.5 hours of actual driving tasks on a highway, separated by 15 minutes of rest. Subjective response to fatigue and sleepiness was obtained by employing Karolinska Sleepiness Scale (KSS), while several eye-blink parameters (blink duration, blink frequency, percent of eye closure, and micro-sleep) were analyzed offline via a continuous recording of the subject’s facial characteristics throughout the driving task. The findings of this study demonstrated that driving for roughly 2.5 hours did not result in undue fatigue. However, an additional driving task of the same duration yielded excessive fatigue, despite the 15-minute rest period given between the two trips. All eye-blink parameters were closely correlated with subjective measures, although more consistent changes were shown by the blink duration. It was concluded here that prolonged driving, as part of a professional job, is closely associated with undue fatigue that represents a road safety risk factor.

Keywords

• eye-blink parameters
• fatigue
• karolinska sleepiness scale
• prolonged driving
• sleepiness