Theoretical and Empirical Study of Pedestrian Outflow through an Exit

In this paper, we have detailedly studied the factors of increasing and decreasing the pedestrian outflow through an exit. One of the major factors is a conflict. In the floor field model, which is a pedestrian model using cellular automata, the conflicts are taken into account by the

friction parameter

. However, the friction parameter is a constant and does not depend on the number of the pedestrians conflicting at the same time. We have extended the friction parameter to the

friction function

, which is a function of the number of the pedestrians involved in the conflict. Furthermore, we also consider the effect of turning around at the exit and the effect of avoiding conflicts by going through the exit one after the other, i.e., zipper effect. The results of theoretical analysis of the extended model, which includes three new effects, agree with the experimental results much better than the previous model. We have also found that putting an obstacle in front of the exit increases the pedestrian outflow from our experiments. The friction function clearly explains the mechanism of the effect of the obstacle, i.e., the obstacle blocks a pedestrian moving to the exit and decreases the average number of pedestrians involved in the conflict.