Passing manuever: survey, some models and simulations

Head‐on collisions cause more serious consequences of road accidents. These collisions are often due to an error of passing maneuver, on two‐lane highways. The Passing Sight Distance (PSD) has always been a subject of studies and research that underline two series of factors that influence the PSD mainly: the first is the size and performance of vehicles, the second is the driver responses to environmental stimuli. This paper presents a study on the differences in some current procedures and guide‐lines used to estimate minimum PSD requirements for highway design. The research starts from a field study of passing maneuvers on two‐lane highways and from a collection of characteristic data of passenger cars. A data obtained by video recordings was used to study some factors influencing the distance value as the actual speed, acceleration (pickup) of vehicles. From the two classical rule models (flying passing, Italian rules, accelerative passing, U.S.) and some modified to these it has simulated the PSD values with data brought by physical characteristics and performance of the passenger cars sold in Italy. The data were corrected with some behavioral characteristics hypothesized for the drivers. It has been supposed three kinds of drivers: a prudent, a normal and an aggressive driver. These drivers with different behavioral kinds influence the simulation data. At the end is showed an analysis of different PSD models and a first approximate model that could link the PSD to the passing vehicle speed