Monotony of road environment and driver fatigue a

Monotony of road environment and driver fatigue: a simulator study Anil Divvela Kenny Stauffer

Purpose • The objective of this study was to evaluate the impact of the monotony of a road environment on driver fatigue

Previous Research • Sleep related accidents may account for at least 40% of fatal accidents (Desmond & Matthews, 1996). • Risk of falling asleep is higher on straight, monotonous roads in situation of low traffic (Sagberg, 1999) • A situation is said to be monotonous is when stimuli remain unchanged or changing in a predictable manner (Mc. Bain, 1970)

Theoretical Basis • Theory is there is a link between monotony of road environments and driver fatigue.

Applicability-practical Contribution • The contribution would be to prevent future car accidents by understanding the link between driver fatigue and monotony. • This might lead to design changes in cars to help drivers stay awake. Or inform them of impaired driving patterns. Highway designers could also build roads that increase visual stimulation. •

Theoretical Contribution • The theoretical contribution is understanding how monotony effects drivers. • How fatigue and monotony of road conditions correlate with the number of accidents.

Methodology • Fifty-six male university students participated in two simulator studies • There was a fifteen minute break between studies to diminish fatigue effect from the first study.

Data Collection • Variables – Steering Wheel Movement (SWM) • Larger steering wheel movements are needed to correct larger lane deviations. – Standard Deviation of Lateral Position (SDLP) • Deviations from the center of the lane. – Standard Deviation of Steering Wheel Movement (SDSWM) • Shows the extremes of the larger steering wheel movements.

Statistical Analysis • The SWM mean amplitude increase over time is significant because it indicates there was a an effect of fatigue on steering behavior.

Statistical Analysis • There was significant results for the frequency of the steering wheel movements. • SWM (from 1° to 5°) decreases with time (P<0. 001). • SWM (from 6° to 10°) increases with time (P<0. 001).

Conclusions • No significantly different results of SWM amplitude or SDSWM for road A and road B.

Conclusions (cont. ) • The frequency of large steering wheel movements were more prevalent when driving on road A than road B (P<0. 001). • Interaction effect between time and monotony factors is marginal (P<0. 062).

Future Research • Evaluate the impact of interruptions of monotony that are more pronounced. • Factors such as size, color, intensity, shape and content of the visual stimulation are dimensions that should be targeted.

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