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. TNO Human Factors Research Institute was commissioned to carry out a study into driver comfort and driver behaviour in an AVG system, focusing on the exit manoeuvre. Three types of transfer of control between the automated system and the driver were used: (1) After initiation by the driver the vehicle control is transferred instantaneously; (2) After initiation by the driver the automated system controls the vehicle to an appropriate gap in the adjacent lane before control is transferred; and (3) the automated system initiates the automated gap search. The main conclusions are that in case of slow traffic in the manual lanes drivers have problems to safely leave an automated lane. Increasing level of automation, low traffic density and small speed differences increase the time margins, but do not have a direct link to the occurrence of conflicts. Increased trust in the automated system improves driver comfort. However, the instruction on reliability does not alter the monotonous relationship of decreasing comfort with decreasing headway as was found in a previous experiment. The instantaneous transfer of control received a higher rating on the `perceived usefulness' dimension than the automated gap search mode. (A) See also C 5822 (IRRD 882979).
Abstract