Research on driver's wrist motion pattern and fatigue characterization methods.

Objectives. Studies have shown that driving fatigue leads to changes in driving behavior. The aim of this study was to analyze the effects of sleep deprivation and prolonged driving time on drivers' wrist motion characteristics. Methods. Seventeen participants were recruited to participate in a 90-min simulated driving experiment after normal sleep and sleep deprivation, and wrist-worn wearable sensors were used to record the acceleration of the driver's wrist and to characterize it in the time domain, frequency domain and entropy. PERCLOS was used as the standard to clarify the wrist motion characteristics of drivers in awake and fatigued states and to explore the trend of wrist motion characteristics with prolonged driving time. Results. Fifteen participants completed two experiments. Sleep deprivation and driving time prolongation induced driving fatigue, which increased the low-frequency power (p < 0.05) and decreased the entropy (p < 0.05) of the driver's wrist acceleration, leading to a decrease in the driver's subtle adjusting maneuvers to the steering wheel and an increase in the rapid and large adjustments. Sleep deprivation led to an earlier onset of driving fatigue. Conclusion. Wrist movement characteristics can be used to reflect the driver's fatigue state, which is of great value for road traffic accident prevention.