Experimental study on relaxation time in direction changing movement

Author:  Liu, C., Song, W. G., Fu, L. B., Lian, L. P., Lo, S. M.

Journal: Physica a-Statistical Mechanics and Its Applications

DOI:  10.1016/j.physa.2016.10.037

Keywords: Pedestrian traffic, Social force model, Controlled experiments, Relaxation time, Direction sensitivity, social force model, pedestrian flows, turning strategies, cellular-automata, dynamics, simulation, evacuation, parameter, behavior, walking, Physics

Abstract: 

Controlled experiments were conducted to clarify the movement characteristics of pedestrians in direction changing processes. We track pedestrians' trajectories and map them into real space coordinates by the direct linear transformation method. In the acceleration process, the relaxation time and free moving speed in our experiments respectively equal 0.659 s and 1.540 m/s, which are consistent with those for Chinese participants in other experiments. Meanwhile, the values of relaxation time in the direction changing process are calculated by a derived equation from the concept of the social force model. It is observed that the relaxation time is not an invariable parameter, and tends to increase with an increase in the angular difference. Furthermore, results show that pedestrians are insensitive to a tiny angular difference between instantaneous velocity and desired velocity. These experimental results presented in this work can be applied in model development and validation. (C) 2016 Elsevier B.V. All rights reserved.