Validation of a driving simulator for work zone design

The research project aimed at calibrating and validating the driving simulator of the European Interuniversity Research Center for Road Safety to enable its use for design and verification of the effectiveness of temporary traffic signs on highways. The research was developed through the following steps: (a) a survey of speed measurements on highways next to a work zone of medium duration, (b) reconstruction in virtual reality of the real situation by using the driving simulator and subsequent running of a series of driving tests, and (c) statistical analysis of the field speeds and of the speeds from driving simulations for validation of the simulator. The surveyed work zone was located on Highway A1 from Milan to Naples, Italy. Speed measurements were conducted with a laser speed meter in the transition area, the activity area, and the termination area, and in the advance warning area speeds were shot with a camera from an overpass. Speed data from the field and the simulator were analyzed by using the bilateral Z-test for nonmatched samples to determine whether drivers responded differently in the simulator compared with their response during the real driving experience. The activity carried out revealed that differences between the speeds observed in the real situation and those measured with the simulator were not statistically significant.