In the study presented in ViP publication 2013-1 the validity of the simulator was assessed using data collected in two earlier experiments. The validation analysis had three focuses: 1) general driver and driving behaviour related to driver sleepiness, 2) speed profile at change in posted speed limit, and 3) drivers’ subjective experience of the vehicle, the driving environment and the own driving performance. The results showed that there were significant differences in mean speed, blink duration, percentage road centre (gaze), radius of 95 per cent cone (gaze) and KSS between the simulator and the real road. No such differences were found for left and right line crossings. For all indicators except blink duration, there was no interaction effect between platform (simulator vs. real road) and time on task, which indicates that the signs of sleepiness vary in a similar way regardless of platform. At the change in posted speed limit, speed was in general higher and it decreased more in the simulator than on the real road. When the drivers were asked to judge the validity in terms of realism, staying alert, handling of boredom, etcetera, they found it more difficult in the simulator than on the real road, which indicates a relatively low absolute validity. The drivers also experienced a higher degree of lack of control in the simulator compared to the real road. In conclusion, differences between the simulator and the real road with respect to driving and driver behaviour as well as subjective experiences were found, mainly in terms of speed, level of sleepiness and subjective experience of the vehicle. However, the signs of sleepiness and the development of sleepiness over time are similar in the simulator and on the real road, although the level is higher in the simulator. Thus, there is a relative but not absolute validity with respect to driver sleepiness. Similarly, there seems to be a relative validity for speed and changes in speed. (Author/publisher) This report may be accessed by Internet users at http://www.vti.se/sv/publikationer/simulator-validation-with-respect-to…
Samenvatting