An empirical study on the effect of an obstacle on the inflow process

The inflow process of pedestrians is a common phenomenon in daily life, yet it has received little attention in the pedestrian dynamics field. This study aims to investigate the impact of an obstacle on the inflow process and determine if the conclusion that the existence of obstacles at the exit may improve evacuation efficiency also applies to the inflow process. A series of experiments were carried out to investigate the impact of an obstacle on the inflow process by setting a stationary pedestrian as an obstacle and changing the distance between the obstacle and the entrance. The results indicate that the presence of an obstacle has a significant impact on pedestrian trajectory, with a notable increase in the deflection angle of pedestrian trajectories. However, the stationary pedestrian has no statistical impact on the dynamic system of the entry process, such as the specific flow rate and time headway. The presence of the obstacle pedestrian significantly inhibits the movement speed of pedestrians after entering the room. The risk degree of the crowd was evaluated using ‘crowd pressure’, which is the product of density and speed variance. The presence of the obstacle effectively reduces the high ‘crowd pressure’ in front of and behind the entrance, making the entire entry process safer. The distribution of pedestrian destinations in a room is uneven, and the presence of the obstacle can affect pedestrians to stop in areas close to the entrance and on both sides of the obstacle. Therefore, our research results indicate that there is a difference in the impact of pedestrian obstacles at the entrance and exit obstacles on pedestrian dynamics. This difference deserves researchers’ attention and our findings can provide useful references for risk control and crowd management during the inflow process.