Assessing Pedestrian Behavior Around Autonomous Cleaning Robots in Public Spaces: Findings from a Field Observation

2025-08-19

AI Summary

This study investigates how autonomous cleaning robot types and motion patterns influence pedestrians’ lateral avoidance behaviors, including those of distracted individuals. Using field observations and video coding in public spaces, we quantitatively analyzed trajectories of 498 naturally walking pedestrians. Results show that approximately 8% were distracted by mobile devices, yet their avoidance behavior did not significantly differ from non-distracted pedestrians. In contrast, robot size and motion pattern exerted substantial effects: robots following an offset rectangular path elicited more frequent and shorter-distance lateral adjustments compared to those moving along straight paths. These findings highlight the critical role of dynamic motion features—particularly path geometry—in shaping pedestrian anticipation and reactive responses. The study provides empirical evidence supporting the design of more predictable and dynamically transparent robot behaviors in human–robot interaction (HRI), offering novel insights for improving safety and fluency in shared pedestrian environments.

Technology Category

• Intelligent Robots: Motion and Path Planning
• Humans and AI: Human-Aware Planning and Behavior Prediction
• Computer Vision: Motion & Tracking

Application Category

• Responsible Web: Machine-in-the-loop, human agency and autonomy
• User Modeling, Personalization and Recommendation: Practical large-scale studies of user experience
• Security and Privacy: Large-scale security measurements

Abstract

As autonomous robots become more common in public spaces, spontaneous encounters with laypersons are more frequent. For this, robots need to be equipped with communication strategies that enhance momentary transparency and reduce the probability of critical situations. Adapting these robotic strategies requires consideration of robot movements, environmental conditions, and user characteristics and states. While numerous studies have investigated the impact of distraction on pedestrians' movement behavior, limited research has examined this behavior in the presence of autonomous robots. This research addresses the impact of robot type and robot movement pattern on distracted and undistracted pedestrians' movement behavior. In a field setting, unaware pedestrians were videotaped while moving past two working, autonomous cleaning robots. Out of N=498 observed pedestrians, approximately 8% were distracted by smartphones. Distracted and undistracted pedestrians did not exhibit significant differences in their movement behaviors around the robots. Instead, both the larger sweeping robot and the offset rectangular movement pattern significantly increased the number of lateral adaptations compared to the smaller cleaning robot and the circular movement pattern. The offset rectangular movement pattern also led to significantly more close lateral adaptations. Depending on the robot type, the movement patterns led to differences in the distances of lateral adaptations. The study provides initial insights into pedestrian movement behavior around an autonomous cleaning robot in public spaces, contributing to the growing field of HRI research.

Problem

• Impact of robot type on distracted pedestrian movement behavior
• Effect of robot movement patterns on pedestrian lateral adaptations
• Assessing pedestrian behavior around autonomous cleaning robots

Innovation

• Field observation of pedestrian-robot interactions
• Analyzing robot type and movement pattern effects
• Comparing distracted and undistracted pedestrian behaviors