An extended model for describing pedestrian evacuation considering the impact of obstacles on the visual view

Abstract

In the process of emergency pedestrian evacuation, higher obstacles in the building will block the vision of pedestrians, thus affecting the evacuation. Therefore, to study the impact of obstacles on pedestrian vision, a cellular automata model considering the effect of obstacles on the visual field was established. The model divides pedestrians into two categories: guiders and ordinary pedestrians. Guiders evacuate based on the static field improved by the Dijkstra algorithm. Ordinary pedestrians have different movement modes in different areas, and the concepts of “following field”, “herding field”, “blinding field” and “guiding field” are introduced to calculate their transfer probability. The influence of obstacles on the field of vision is mainly on the herding and following behavior of ordinary pedestrians. Simulation scenes are set and arithmetic case analysis to verify the effectiveness of the model. Parameters affecting evacuation behavior, including pedestrian density, the radius of view, the proportion of guiders, and the type of obstacles, are discussed to study the influence of these parameters on the evacuation process. The study shows that the obstacles affecting the field of vision greatly weaken the guide effect of the guiders and reduce the probability of rational herding behavior, on the other hand, negatively affecting the evacuation efficiency. Moreover, the lower proportion of guiders cannot effectively reduce the evacuation time due to local congestion. Further, there exists a worst radius of view which lead to the longest evacuation time. The main conclusions are that the effects of these new extensions effectively modify the effect of the obstacles and can therefore be important for improving the models and providing better estimates.