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

Abstract Autonomous robots of different kinds become more and more salient in our everyday life and because the spatial proximity of robots has an effect on the well-being of humans, researchers try to find and give appropriate guidelines regarding spatial proximity. In doing so, these studies rely on a few different concepts (e.g., safety or comfort) and on a rather large variety of different measurement approaches thereof. From psychology we know that the conceptual framing, as well as the way we measure (number of items, labels of scales, and wording) can affect the outcome of such studies. We present the first study that addresses and evaluates the consequences of these different conceptual and methodological approaches. We found that there is significant interaction between the different measurement approaches and the determined appropriate distance. This interaction was significant for both lateral passing distances and frontal approaches. This can have real-life effects, since the appropriate distances determined in studies such as the present may directly influence actual programming algorithms. Furthermore, by using three different types of robots, we were able to show that the humanization of mechanoids can lead to the acceptance of smaller distances by humans.