As domestic environments are increasingly required to meet diverse and changing human needs within constrained spaces, physical reconfigurability offers a promising solution. We developed a full-scale, manipulable room prototype as an exploratory co-design instrument, enabling participants to bodily explore and reflect on reconfigurable living spaces. Through 12 sessions with 30 participants involving brainstorming, bodystorming, and interviews, we identified spatial design patterns and elicited perspectives on reconfigurable domestic environments. Our findings contribute a design pattern catalogue for reconfigurable spaces, alongside insights into the lived experience of reconfigurability. We also discuss design principles, three affordance-based design dimensions that capture value tensions: empowering vs. restrictive, utilitarian vs. hedonic, and futuristic vs. practical, as well as lessons from co-design with a room-scale prototype. We demonstrate agile, room-scale prototyping as a methodological approach for spatial HCI research, advancing toward human-computer habitation, where interactive systems become inhabited built environments that support human values, creativity, and autonomy.

Dental clinics can be challenging sensory environments, creating discomfort and stress, especially for neurodivergent individuals with Sensory Processing Disorder. Interactive environmental systems offer potential to transform these spaces, providing adaptable, sensory-inclusive experiences. However, the design space for environment-based interventions in dental settings remains largely unexplored. To address this, we conducted in-depth 2-hour co-design sessions with 13 neurodivergent participants to explore environment-based strategies to meet diverse sensory needs. We identified five core design goals for inclusive dental environments: experience transformation, distraction, exposure management, restoration, and social facilitation. Our technology-agnostic design catalogue can inform multiple implementation approaches, including projection mapping, ambient displays, and responsive physical elements. We contribute design patterns for interactive environmental systems, methodological insights for participatory design with neurodivergent communities, and demonstrate how tangible materials serve as proxies for environmental interventions, with implications for Augmented Reality system design. This study advances inclusive design practices and highlights co-designing with neurodivergent individuals.

Eye contact between strangers, even fleeting, can spark interaction and foster connection, happiness, and belonging. Yet in public spaces, such encounters are often suppressed by “civil inattention,” with many people absorbed in their phones. We explore how reconfiguring the ambient environment with MirrorBot, a mobile robot with adaptive mirrors, can encourage social encounters by subtly redirecting glances. By shifting reflections between self- and mutual recognition, MirrorBot invites serendipitous eye contact, shared awareness, and low-stakes engagement. In a controlled 2×2 between-subjects study with 90 participants (45 dyads) across four conditions (MirrorBot, Bot-only, Mirror-only, and Control), we found that MirrorBot led participants to initiate conversation more often, feel greater closeness and togetherness, and have more enjoyable interactions. Our findings position robots not only as social agents but as socio-spatial interfaces that choreograph sight lines and shared attention in physical space, opening new possibilities for technologies that cultivate human connection in public life.

Brief eye contact with strangers can foster connection, belonging, and positive affect, yet such moments are often scarce in public spaces. This paper investigates how a spatially situated robot can reshape the visual field of a shared space to influence how strangers notice and respond to one another. We present MirrorBot, a mobile robot equipped with two actuated mirrors that dynamically redirect reflections to reshape sightlines between people. In a study with 32 strangers in 16 pairs in a waiting-room setting, MirrorBot elicited patterns such as low-stakes icebreaking, nonverbal synchrony, joint sensemaking, asymmetric engagement, and avoidance. Participants also attributed multiple roles to the robot, such as mediator, observer, magnifier, or disrupter, revealing that its social meaning was fluid and co-constructed. Our work extends HRI by showing that robots can act not only as conversational partners but also as spatial mediators, curating opportunities for human–human connection through the reconfiguration of spatial relationships

Robot morphology-the form, body shape, and structure of robots-makes up a key design space in human-robot interaction (HRI), shaping how robots function, express themselves, and interact with humans. Yet, despite its importance, little is known about how design frameworks might guide form exploration and generation. To address this gap, we introduce Elements of Robot Morphology, a design framework that identifies five fundamental elements: intelligence, kinematics, end effectors, locomotion, and structure. Based on an analysis of robots in the IEEE robot database, this framework provides a foundation for exploring diverse robot forms. To operationalize the framework, we developed Morphology Exploration Blocks (MEB), a set of tangible blocks that enable designers to physically build and experiment with different morphologies, fostering hands-on and collaborative exploration. We evaluated the framework and toolkit through a case study and a series of design workshops, demonstrating their support for analysis, ideation, reflection, and collaborative creation in robot design.

This study investigates the application of real-world Reinforcement Learning (RL) in facilitating synchronized movement and fostering social connections during initial interactions between strangers. We introduced a novel, projection-based system where an RL agent is projected onto a table to interact with participants through its movements. Our research involved the development and testing of a Deep Q-Network (DQN) integrated with a Long Short-Term Memory (LSTM) model that identifies synchronized movements and determines the reward for the DQN. The preliminary results showcase the effectiveness of the LSTM model, revealing that synchronized movement can be a potent reward mechanism, enabling RL agents to learn effective policies. The initial findings indicate the feasibility of the RL approach in enhancing social interactions, providing partial support for our designed actions.

While robots are traditionally envisioned as physical entities that move through, sense, and act upon the environment, a new category is emerging: the inhabitable robot, or "robot-room," which redefines human-robot interaction by immersing us within the robot itself. As a first step in exploring this novel design space, we developed a full-scale, rapid-prototyped robot-room—not a simulation or scale model—and conducted a co-design study with 30 participants. Inside this immersive space, participants explored new forms of human-robot interaction, engaging their perceptual faculties for "knowing spaces." Our findings inform our ongoing development of a fully operational robot-room and offer valuable insights into expanding the concept of human-robot interaction to one of human-robot cohabitation.

Central to the human experience is establishing a connection with individuals who are unfamiliar with one another—strangers. We describe results from a field study that deployed SocialStools , a socio-spatial interface with mixed-reality experience, to support ice-breaking between strangers in a public space. Synthesizing existing social psychology theories, we propose a human behavior framework with distinct, interconnected behavioral components, and then apply this framework as an instrument to analyze the “ice-breaking” process amongst 81 strangers assigned to 27 groups using SocialStools . Our analysis identifies recurring behavioral patterns that demonstrate the fluid and emergent nature of interpersonal spatial adjustments, emphasizing the dynamic aspects of proxemics. Our contributions are the results of our empirical field study with a socio-spatial interface that advances our understanding of how strangers interact when uninstructed, and a theory-based, behavioral framework—an analytical instrument to examine the dynamic experience of ice-breaking.

Interacting with strangers can be beneficial but also challenging. Fortunately, these challenges can lead to design opportunities. In this paper, we present the design and evaluation of a socio-spatial interface, SocialStools, that leverages the human propensity for embodied interaction to foster togetherness between strangers. SocialStools is an installation of three responsive stools on caster wheels that generate sound and imagery in the near environment as three strangers sit on them, move them, and rotate them relative to each other. In our study with 12 groups of three strangers, we found a sense of togetherness emerged through interaction, evidenced by different patterns of socio-spatial movements, verbal communication, non-verbal behavior, and interview responses. We present our findings, articulate reasons for the cultivation of togetherness, consider the unique social affordances of our spatial interface in shifting attention during interpersonal communication, and provide design implications. This research contributes insights toward designing cyber-physical interfaces that foster interaction and togetherness among strangers at a time when cultivating togetherness is especially critical.