In interaction with other road users, time is often a limiting factor in deciding what is the appropriate action in that particular situation. However, it seems plausible that drivers must have some kind of expectation of what is about to happen in the next moments in order to be able to react in time. In a study into the information processing of drivers involved in interaction situations, a model has been formulated which is based on Endsley's Situation Awareness (SA) model and Wickens' model of Information Processing. Also, in this model two kinds of expectancy are distinguished; ‘long term’ and ‘short term’ expectancies. Long term expectancies are derived from the driver’s mental model of the situation and are thus based mainly on experience and education. An example of a long term expectation is the expectation that road users on a motorway will all drive in the same direction. Subsequently, short term expectancies are based on these long term expectancies and include information from the situation at that particular point in time. An example of such an expectancy is the expectation that another road user will be at a certain position in the next moment. Although it is not necessary for road users to have exactly the same expectations, it is however important that these expectancies are not conflicting. This notion should be kept in mind when designing ADAS that aim to support interaction behaviour. It is important for the sake of traffic safety, that car drivers using ADAS do not cause other road users to have conflicting expectations of their behaviour due to unfamiliar behaviour caused by the use of ADAS. (Author/publisher)
Abstract