Avoidance behavior and movement characteristics of pedestrians under mobile phone distraction

Smartphone use while walking has become increasingly prevalent, which significantly affects pedestrian safety and increases the risk of traffic accidents, especially in avoidance scenarios. Therefore, to reveal the avoidance mechanism and gait features under mobile phone use distractions, a series of walking experiments under varying distraction conditions including no phone use, text-browsing, message-sending, and video-watching were conducted. Multiple types of data such as physiological signals including the electrocardiogram (ECG) and electrodermal activity (EDA), and high-precision motion trajectories were synchronously obtained. To characterize the entire avoidance process, three critical positions including the start point, maximum point and end point are identified in this paper. The results show that distracted pedestrians initiate evasive maneuvers when they are close to obstacles, whereas non-distracted pedestrians prefer to avoid obstacles in advance. Moreover, the right-side avoidance strategy is adopted by most pedestrians under different distraction levels. Physiological signal indicates that distracted pedestrians experience elevated levels of psychological stress. Besides, the walking speed is significantly decreased in distracted circumstances. The gait analysis demonstrates that distracted pedestrians exhibit shorter step length, larger step width and longer step time during the avoidance phase. Furthermore, the real-time messaging task consumes large cognitive resources of pedestrians, which has the most pronounced impact on pedestrian safety. The study elucidates how the use of smartphones affects the avoidance mechanism of pedestrians, which can help develop intervention measures and safety strategies to reduce the risk of distracted walking in public places.