2020 年 36 巻 1 号 p. 10-21
It is important to keep an appropriate distance from other vehicles when driving. In recent years, tailgating has become a social problem. It was hypothesized that being approached by other vehicles makes drivers feel strong pressure and then people feel it as tailgating. The purpose is to reveal the amount of their personal space between vehicles during driving and the sense of distance by comparing the inferred distance with the measured distance. This experiment was conducted based on 4 factors: the sizes of the vehicle （small/large）, approaching methods （approaching the stopped front vehicle/being approached from the rear vehicle）, measurement conditions （an inferred distance/an actual distance）, and gender. The results are as follows. Drivers showed their personal space larger when being approached than when approaching the vehicle ahead. Furthermore, the bigger the size of the vehicle in front and behind was, the larger the space they need. In addition, there was a significant tendency for gender. The inferred distance between the vehicles is closer than the measured distance. It was revealed that the personal space between vehicles were effected by the direction of approaching and the size of vehicle, and they felt closer than the actual distance between vehicles in some conditions.