Influences of On-Road Driving Fatigue, Mental Workload on Drivers' Performance

Influences of drivers' fatigue on driving secondary task, physiological indices, and subjective mental workload (MWL) were investigated between two different driving times during one day in real-road condition. Ten taxi drivers were required to do verbal arithmetic calculations during driving in the morning and in the afternoon, respectively. Performance of secondary task, physiological indices, subjective MWL and subjective feeling of fatigue were compared. Difference of calculation deviances was significantly found, with more errors in the morning than in the afternoon. Physiological indices also showed different results. The other two subjective measurements were also compared. The results showed practice effect during driving. The study may have implications for technological countermeasures against driving figure.