A sudden variation in the visual field reduces driver’s accuracy in estimation of the speed of the car ahead

Abstract

We offer the hypothesis that a variation in the visual environment of a driver affects their performance in estimating the speed of a car in front. The hypothesis was tested in a driving simulator with 18 drivers by recording their ability to estimate the relative speed of a car ahead when exposed to sudden variations in the visual environment. The sudden variation was produced by briefly (200 ms) masking the driving environment with a grey frame. The results of our study confirm the hypothesis, as the flashed mask significantly lowered the drivers’ accuracy in estimating the speed of a car ahead. The results also show that it is possible to cope with variations in the visual environment and to partially recover from the loss of accuracy. The findings are relevant to the layout of driving environments, such as the placement of dynamic advertisements along the side of the road or the entrance zones of tunnels, and to the training of drivers.

Practitioner summary: In our driving simulator study, we showed that sudden transitions in the visual environment reduce a driver’s performance in evaluating the speed of the car ahead and are therefore a factor in accidents and traffic jams. Transitions should be limited, and drivers should be prepared for the effect of transitions.

Abbreviation: ANOVA: analysis of variance

Keywords:

• Driving safety
• speed estimation
• visual environment
• car-following
• signal detection theory

Disclosure statement

No potential conflict of interest was reported by the author(s).