A driving simulator study was carried out to study driver behaviour in case of an Automatic Vehicle Guidance (AVG) system, implemented on the left lane of a motorway. The study which is discussed in this report focused on the acceptance of tight margins in lateral direction. Subjects were driving in an automated mode on an automated lane with varying width, partly physically separated from the manual traffic lanes by means of a barrier and partly directly adjacent to the normal manual traffic lanes. Subjects also drove the same route while steering the car themselves. The results show that the comfort level in an AVG system is not affected by a physical separation between the AVG lane and the manual lanes, nor by the speed driven within the AVG lane. The width of an AVG lane does affect comfort. A moderate reduction of lane width does not have a great impact on comfort. However when the lane width approaches the vehicle width, comfort is distinctly reduced. In manual driving, not only reduced lane width but also a barrier is a discomfort factor. In order to cope with the narrow lane condition subjects reduced their speed and shifted their course away from the barrier. Steering effort was increased in the tight lane conditions.
Abstract