关键词: 交通工程, 幼儿安全, 可控实验, 校车疏散, 运动特性

Abstract: With the large-scale deployment of new energy school buses, the fire hazard triggered by lithium-ion battery thermal runaway has become increasingly prominent. Constraints such as narrow aisles within vehicles significantly limit the evacuation efficiency of young children during emergencies. To address this issue, this paper designed and conducted individual and single-file controllable movement experiment of young children, focusing on the constraint of school bus passage width. Based on image processing methods, the movement trajectory data of the children were extracted, and the influence of passage width and walking posture on movement trajectory, speed, acceleration, spatiotemporal characteristics, and fundamental diagram were quantitatively analyzed. The results show that aisle width has a significant impact on the walking speed in individual and single-file experiment of young children. In the individual movement experiment, when the passage width increased from 0.30 m to 0.50 m, the average speed of forward and sideways walking increased by approximately 42.70% and 60.50%; in the single-file movement experiment, the average speed of forward and sideways walking increased by approximately 88.90% and 18.00% , respectively. This study reveals the coupling relationship between forward distance and acceleration and quantitatively defines three functional zones-deceleration and collision avoidance, steady- state following, and acceleration and traction- using 0.70 m (mean zero point) and 2.05 m (gain inflection point) as boundaries. This study provides empirical data support for the interior spatial design of school buses and the emergency evacuation safety of young children.

Key words: traffic engineering, children safety, controlled experiments, school bus evacuation, movement characteristics