Understanding overtaking, beyond limitations of the visual system in making spatiotemporal estimations

Motivation -- To enrich our understanding of the factors that influence the decision to overtake against two way traffic, and this, beyond the limitations of the human visual system in making spatiotemporal estimations. Such understanding may be valuable for the design of future adaptive aid systems. Research approach -- An explorative naturalistic observation was conducted with a vehicle equipped with three cameras travelling at normal speed for a total distance of 300 km. 40 unobtrusive observations of overtaking episodes were recorded. Findings/Design -- The data is still at the analysis stage. There is however evidence that before the decision to overtake (i) there is a preparation phase prior to the initiation of the overtaking manoeuvre which deals with the intentions/state of the driver ahead and (ii) frequent users of the particular road will use their specific knowledge and initiate overtaking manoeuvres Research limitations/Implications -- The study has an explorative character mainly for generating hypotheses and cannot as such prove its findings without subsequent complementary methods. Originality/Value -- A contribution of the present paper is on the observation method which ensures the collection of data with a high degree of ecological validity. Take away message -- Spatiotemporal estimation just prior to manoeuvre initiation is only one of the factors influencing the decision to overtake. For understanding naturally occurring overtaking manoeuvres longer time frames of analysis are needed