Passing behavior on two-lane roads in a real and in a simulated environment

Passing maneuvers allow faster drivers to continue driving at their own desired speeds without being delayed behind an impeding vehicle. On two lane rural roads, this requires from the passing driver to occupy the opposing lane. This has tremendous implications on safety and operation of two-lane roads. In the literature, several studies investigated the passing behavior of drivers, and some have used driving simulators to analyze drivers’ behavior during following and passing maneuvers. However, the validity of simulators has not been ensured, as their results have rarely been compared with real data. The objective of this study is to compare drivers’ passing behavior as observed in the field with 49 passing behavior in a driving simulator. This may improve both methods to validate the use of simulation instead of observations. For this purpose, data on passing performance and passing gap acceptance decisions is required. This paper carried out a comparative analysis of the most significant variables related to passing behavior. The results showed similarities between passing time and passing distance of completed maneuvers (during the occupation of the opposing lane). However, drivers passed faster in the driving simulator, keeping higher clearances. Gap acceptance decisions were also found to be similar, as the distributions of both accepted and rejected gaps were similar, although critical gaps were found to be lower in the driving simulator. This might be explained by the absence of objective risks. Consequently, the applicability of driving simulation seems reasonable, although some improvements are still possible, in order to account for sight distance limitations, replicate age and gender distributions, and reproduce better the opposing 60 traffic flow