Road safety analysis: a study on the visual perception of road signs using a rriving simulator

Driver’s visual perception is among the human factors that most influence road safety. A driver who does not correctly perceive external inputs can increase the probability of an accident to occur. This research intends to contribute to active safety studies by analyzing how the perception of vertical road signs in urban area may vary under “standard” traffic and visibility conditions, for drivers in various age groups. To understand the visual perception of vertical signs, a simulation experiment was conducted in which a sample of drivers traveled an urban route using a car simulator. From the results it emerges that vertical signs are very rarely observed by drivers: on average, only one sign in five was seen. The data collected show a frequency observation of vertical signs between 100 ms and 500 ms, with an average observation time of 200 ms. No one sign class was observed more than others, and the observation rates were very low (<20%) for all sign classes. The results may help identify future applications to improve the visibility and perception of vertical road signs in urban areas.