Kazumichi MATSUMIYA^* and Hirohiko KANEKO¹

Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
¹Department of Information Processing, Tokyo Institute of Technology, 4259-G2-3 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan

(Received January 29, 2008; Accepted March 17, 2008)

When cars are oncoming in the opposite lane of a road, a driver is able to judge whether his/her car can cross the road at an intersection without a collision with the oncoming cars. We developed a model for the human judgment used to cross a road between oncoming objects. In the model, in order to make the judgment to cross the road, the human visual system compares the time interval it takes for an oncoming object to pass the observer with the time interval it takes for the observer to cross the road. We conducted a psychophysical experiment to test the model prediction. The result showed that human performance is in good agreement with the theoretical consequence provided by the model, suggesting that the human visual system uses not only the visually timed information of the approaching object but also the timed information of self-action for the judgment about crossing the road.

Key words: motion in depth, time to contact, visually timed action

^*E-mail address: kmat@riec.tohoku.ac.jp