Experimental study on pedestrians' collision avoidance

Modeling and simulating of pedestrians movement have attracted much attention because they provide reproducible results, which are important to evaluate evacuation facilities and risks. It is well accepted the movement of individuals is affected by interactions with others and the environment. However, factors affecting the interactions are not fully studied and experiments are needed. This paper studies the impact of speeds on how pedestrians respond to obstacles, i.e., avoid collisions. Experiments were conducted in which participants were instructed to perform collision avoidance tasks with obstacles at two levels of both normal and high speeds. The avoidance tasks include avoiding collisions by stopping at or bypassing obstacles. Trajectories of participants were extracted from video recordings. How speed affects (1) the timing and magnitude of the deceleration of participants stopping at obstacles; (2) and the minimum distance to obstacles for participants bypassing obstacles were studied. It is concluded that speed significantly affects participants' collision avoidance: compared with participants at the normal speed, participants at the high speed start to stop further away from obstacles with higher deceleration when stopping at obstacles; and they need more space when bypassing obstacles. Results of the experiments are now being used to refine pedestrian models.