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Adaptive head lights

Description
The system consists of electromechanical controlled headlights to ensure optimum illumination of the lane in bends. The headlight is directed into the bend as soon as the vehicle begins cornering. A reduction of the glare to the upcoming vehicles is possible. Vehicle speed, yaw-rate and steering wheel angle can be used as input data for the controller of the system.

Impacts
No reliable safety estimates yet exist. The system should affect safety in the dark, twilight or otherwise in conditions with poor visibility and especially accidents involving parked or stopped vehicles, pedestrians, bicyclists and animals. The total safety effect will rely on how drivers will adapt their behaviour to the increased visibility conditions - previous research suggests that the system will increase speeds in such conditions.

Studies

A general increase in speed was noticed in both AFS and non-AFS groups during the six days of testing. The speed increase was significantly higher in the non-AFS group in city scenario representing urban environment. Drivers with AFS technology did change their driving pattern, but only in terms of driving speed, and no change in lateral distance or steering wheel measures was found.	The results are based on a literature study and a driving test lasting six days. A group of drivers with AFC system was compared with a control group of drivers with no AFS system.	Jenssen, G. D., Bjørkli, C. A., Sakshaug, K., Moen T.	2007	Behavioural Adaptation to Adaptive Front Lighting Systems (AFS): A Six Day Driving Simulator Study. Proceedings of the 14th World Congress on ITS, 9-13 October 2007, Beijing, Peoples' Republic of China.
The extent of road safety impact of such a system will rely on how drivers will adapt their behaviour to the increased visibility conditions.	The results of the study are based on review of earlier results and personal opinions of the author.	Rumar, Kåre	1997	Adaptive Illumination Systems for Motor Vehicles: Towards a More Intelligent Headlighting System (abstract) The University of Michigan, Transportation Research Institute. UMTRI-97-7
Drivers were found to compensate for the improved vision by increasing their speed, which in some circumstances even led to increased accident risks when compared to before the deployment of the reflector posts.	Analysis of accident statistics and automated measurement of vehicle speeds	Kallberg, Veli-Pekka	1991	Reunapaalujen vaikutus ajokäyttäytymiseen ja liikenneonnettomuuksiin (Effects of reflector posts on driver behaviour and accidents) Helsinki. Tiehallitus, kehittämiskeskus. Tielaitoksen selvityksiä (Finnra reports) 5/1991.