What is Appropriate? On the Assessment of Human-Robot Proxemics for Casual Encounters in Closed Environments

Abstract

Increasingly autonomous robots become more and more prevalent in daily life and their proximity to humans may affect human well-being and comfort. Consequently, researchers have begun to study the effect of robotic presence on humans and to establish distance rules. However, studies on human-robot proxemics rely on various concepts (e.g. safety, comfort, perceived safety and expectation conformity) to measure the appropriateness of distances which can affect the outcomes. The impact of using diverging operationalization has not been studied explicitly, thus the first aim of our research was to fill this gap. In two experiments (combined N = 80), placing participants in indirect hallway human-robot interactions, we found that the way appropriateness is operationalized has a significant impact on the results for lateral passing and frontal approaches. The second goal was to gain new insights into the influence of robot appearance on appropriate proximity. Using an ad-hoc created appropriateness scale we reveal that for robots displaying human faces on screens, closer distances are perceived to be appropriate. Our study provides valuable insights into the relationship between measurement methods, robot appearance, and appropriateness, and offers practical recommendations for future research and development in the field of social robotics.