This paper explores the design of expressive movements for service robots in fine-dining restaurants, using a performative approach to understand how robots can be integrated and accepted in complex real-world settings. Drawing on dramaturgical principles, we conducted three research and design activities-speculative enactments, scenario building, and extended reality (XR) simulations-to examine how specific movements of a restaurant service robot and the contexts in which they are performed influence the experiences of guests, serving staff, and managers. We propose that such robots can be conceptualized as “ensemblists,“ capable of adopting multiple roles and collaborating with humans in a larger choreography of service delivery. The study concludes by reflecting on the strengths and limitations of performative approaches in HRI, emphasizing the need to move beyond traditional one-on-one human-robot interaction models and, instead, to consider how robots perform their roles in complex, dynamic environments involving multiple actors.

Social robots have become increasingly prominent in the realm of physical activity promotion. However, the technological complexity and primarily anthropomorphic designs of these robots pose challenges for their application in everyday settings. This study positions spherical robots as an emerging subtype of social robots and explores their potential to promote physical activity at home by identifying useful behavioral design patterns. To this end, we engaged theater professionals and human-robot interaction researchers in a 4-day workshop, leveraging a speculative design methodology. A puppeteer controlling a robotic ball and two actors improvised human-robot encounters in a staged home setting. These encounters were analyzed to identify instances where the ball triggered physical activity. From this analysis, we extracted nine design patterns that articulate robot behaviors for initiating physical interaction. Additionally, our findings revealed that these patterns could be combined into complex sequences to sustain physical activities, which are experienced as meaningful when framed within a narrative. We discuss the contents of these patterns and their potential value for home-based healthcare applications. Our contribution lies in articulating the potential of spherical robots for promoting physical activity at home through design patterns informed by a performative approach to human-robot interaction.

In this article, we report on methodological insights gained from a workshop in which we collaborated with theater professionals to enact situated encounters between humans and robots on a mixed reality stage combining VR with real-life interaction. We deployed the skills of theater professionals to investigate the behaviors of humans encountering robots to speculate about the kind of interactions that may result from encountering robots in supermarket settings. The mixed reality stage made it possible to adapt the robot’s morphology quickly, as well as its movement and perceptual capacities, to investigate how this together co-determines possibilities for interaction. This setup allowed us to follow the interactions simultaneously from different perspectives, including the robot’s, which provided the basis for a collective phenomenological analysis of the interactions. Our work contributes to approaches to HRI that do not work toward identifying communicative behaviors that can be universally applied but instead work toward insights that can be used to develop HRI that is emergent, and situation- and robot-specific. Furthermore, it supports a more-than-human-design approach that takes the fundamental differences between humans and robots as a starting point for the creative development of new kinds of communication and interaction.

To develop and sustain rich social interactions between humans and robots, previous research has mostly looked at task-oriented performance metrics or the ability for a robot to adequately express messages, emotions, or intents. In contrast, our research starts from the premise that movement, as a nonverbal modality of social interaction, can cover other essential aspects of social interaction that do not have to do with the expression of messages, inner states, or drives but that nonetheless contribute to improving the quality of interaction. These aspects have to do with interaction dynamics and highly depend on appropriate action choice. Drawing inspiration from rule-based improvisation, this paper seeks to show that there exists implicit expert knowledge that can be used to inform these movement action choices, contributing to rich, playful, and non goal-oriented interactions between humans and robots. We present an experimental study conducted at a performing arts festival, in which participants interacted with a robot in three simple rule-based movement games, in two conditions: one where the robot was fully controlled by an improvisation expert (Improv Timing/Improv Action) and one where the timing of the actions was controlled by the expert but the robot’s action choices were drawn randomly (Improv Timing/Random Action). This was done in order to focus on action choice, beyond the timing of a response. Our results show that the Improv Timing/Improv Action condition not only performs better in terms of anthropomorphism and animacy, but also increases the interest of people in interacting with the robot for longer periods of time. These results serve as preliminary evidence of how improvisational knowledge in this context contributes to improving the quality of an interaction, and point at the value of further work in this field.

A key challenge in human-robot interaction (HRI) design is to create and sustain engaging social interactions. This paper argues that improvisational techniques from the performing arts can address this challenge. Contrary to the ways in which improvisation is generally used in social robotics, we propose an understanding of improvisational techniques as based on rules that shape motion choices. We claim that such an approach, represented in what we name the “external” and “emergent” perspectives on improvisation, could benefit the way in which robot movement and behaviour is designed and deployed, increasing playful engagement and responsiveness. As an example of this type of improvisation, we discuss how American dancer and choreographer William Forsythe's Improvisation Technologies could be used in an HRI context. We also report on a preliminary experimentation using a Wizard-of-Oz exploratory prototyping system and a participatory design method with professional dancers geared towards the exploration of interactive movement possibilities with a Pepperrobot. Finally, we report on how this workshop offered valuable information about the applicability of these tools, as well as reflections on how it could help increase the level of engagement in the interaction.