Observing Overtaking Manoeuvres to Design an Overtaking Assistance System

Observations of overtaking maneuvers on bi-directional rural roads were carried out to enhance the understanding of driver behavior prior to, during and after an overtaking maneuver. Data were collected to serve as a basis for developments towards overtaking assistance systems. An instrumented vehicle was used to record overtaking maneuvers: this vehicle drove in actual traffic and several speeds were chosen that led to other vehicles overtaking the instrumented vehicle. In total, 48 maneuvers were recorded and analyzed afterwards. The duration of the overtaking maneuvers was analyzed in relation to the applied overtaking strategy and the speed of the instrumented vehicle. Only limited variation in the overtaking duration was found, from which it is concluded that a single type of overtaking assistance system can serve most drivers. Fairly short perception-reaction times were observed, indicating that the decision to perform an overtaking maneuver is made before an appropriate gap in the oncoming traffic stream is available. Overtaking assistance can therefore only be valuable if it is able to assist prior to the emergence of such a gap, otherwise valuable time is lost.