Surfing, like many water sports, offers a unique opportunity to experience natural environments, yet the design of interactive technologies for water activities– “WaterHCI” – so far prioritised athletic performance over experience. To explore this opportunity, we designed SurfSync, a novel wearable system in the form of an actuating vest and a hat that provides oceanic information through sound, vibration, and heat actuation, aimed at enriching the surfing experience as a playful encounter with the ocean. We studied SurfSync in an ocean-based field study with eight surfers. Through thematic analysis of interviews, we articulated the surfers’ experiences, indicating how they made sense of playful cues while in the ocean. By reflecting on our soma design process and the surfers’ experiences, we provide six design strategies to enrich the surfing experience. Our work contributes to the emerging field of WaterHCI by providing insights into how wearables can enrich human-water experiences outdoors.

Dining is a social activity, yet human–computer interaction (HCI) research has rarely examined how extended reality (XR) headsets shape shared restaurant experiences. Although XR can augment taste perception, headsets also obscure facial expressions – particularly pertinent when only some diners wear them. We identify an opportunity to make a wearer’s biodata socially visible via an outward-facing display on the headset to facilitate novel social dining experiences with XR. To explore this, we designed E.A.T. (Expressive Augmented Togetherness), a novel XR dining system that combines food augmentation with external displays depicting physiological arousal and pupil movement to facilitate social interactions. Through interviews following a restaurant field study with five groups of three diners, we examined how the system influenced taste perception and social interactions. We identify six design considerations for socially legible XR systems for dining, ultimately, aiming to inform how HCI can better support social dining experiences.

Emerging technologies such as exoskeletons and electrical muscle stimulation can initiate movement within the human body, blurring the boundary between user and machine. While prior research has explored how such systems augment bodily action, most focus on movement execution rather than decision-making. In this work, we investigate what happens when a bodily-integrated system acts with its own logic and initiates bodily movement alongside users. We present three game scenarios where an exoskeleton controls one arm while the user controls the other, designed to evoke different relational framings: proxy, collaboration, and opposition. Through a qualitative study (N = 16), we examine how users interpret such interactions, and how shared bodily control shapes bodily experience and human-machine relationship. We further contribute a set of implications for designing bodily technologies that decide and move together with users, opening up design possibilities for systems that share bodily control, not merely actuate on users’ behalf.

Advances in emerging technologies, such as on-body mechanical actuators and electrical muscle stimulation, have allowed computers to take control over our bodies. This presents opportunities as well as challenges, raising fundamental questions about agency and the role of our bodies when interacting with technology. To advance this research field as a whole, we brought together expert perspectives in a week-long seminar to articulate the grand challenges that should be tackled when it comes to the design of computers’ control over our bodies. These grand challenges span technical, design, user, and ethical aspects. By articulating these grand challenges, we aim to begin initiating a research agenda that positions bodily control not only as a technical feature but as a central, experiential, and ethical concern for future human–computer interaction endeavors.

Gastrointestinal sounds are a constant part of human physiology, offering potential insights into digestive functions and everyday bodily awareness. However, these sounds are rarely noticed and often socially stigmatised, remaining underexplored in HCI despite calls to recognise the gut as a site for embodied awareness. We extend HCI’s engagement with involuntary biosignals by positioning gut sounds as a uniquely generative context for interoceptive interaction design, where systems can scaffold awareness, reflection, and care. We conducted a week-long in-the-wild qualitative study with ten participants, which showed how making gut sounds audible reshaped bodily awareness, provoked affective responses, and prompted acts of reflection and tinkering. From these insights, we contribute four bodily perspectives – Registering, Reacting, Reflecting, and Responding- that capture the oscillatory nature of interoceptive engagement and offer design strategies that position biosignals as sites of curiosity, care, and awareness that are socially situated.

Sounds play a crucial role in shaping dining experiences. Recently, designers have increasingly integrated them into interfaces that connect diners with food. Yet, little is known about how sounds can function as culinary materials to enrich chefs’ creativity, particularly in creating meaningful auditory interactions that resonate with their culinary creations. Hence, we present GastroConcerto, an auditory dining system that combines a magnetic contact microphone equipped under the plate with a companion mobile application. This system delves into the interactive space between diners and their food to introduce a novel interactive mechanism of dining–sound pairing, enabling chefs to design specific auditory interactions that respond to diners’ individual interactions with the food on dining containers. Through a within-subjects study and field deployment, we examined how GastroConcerto enriches chefs’ creative practices in crafting "sonic dish" experiences. Ultimately, our goal is to shift the ownership of auditory interaction design from interface designers to chefs, thereby supporting their culinary creativity.

Drinking is an inherently multisensory activity, yet the potential of immersive technology to dynamically shape flavor experiences remains underexplored in Human-Food Interaction (HFI) research. We introduce “XTea”, an adaptive beverage cup-based system that integrates large language models to translate natural language input into modifications of a parameterized immersive environment experienced through a headset when drinking bubble tea. Through a study with 12 bubble tea enthusiasts, we derived themes that demonstrate how “XTea” can enrich sensory engagement, support personalized and agentic experiences, and foster social qualities of drinking, pointing toward new explorations for multisensory HFI design. We also present four design strategies for multisensory beverage experiences. Ultimately, we aim to contribute to the advancement of HFI research on how multisensory interaction design can enrich flavor perception and engagement.

Physical augmentation technologies can extend human abilities beyond biological limitations, creating "superpower" experiences. However, as these technologies integrate with the human body, they can also introduce unfortunate negative effects due to the body’s constraints. Inspired by biology, especially the fly-catching mechanism of the flytrap plant, we designed "Flytrap Hand", a provocative artifact that grants users the superpower of accelerated grasping through a distance sensor and electrical muscle stimulation, while resulting in uncertainty. A mixed-method study (N = 12) revealed that participants appreciated the fortunate superpower effects, but also highlighted the unfortunate effects of discomfort, skepticism toward bodily automation, and ethical concerns. Building on these findings, we propose a design framework for designing more thoughtful superpower experiences that account for potential negative effects. Ultimately, with our work, we aim to help designers consider not only superpowers’ positive but also negative effects early on as they may be difficult to rectify in hindsight.

Game studies and HCI research on embodied experiences and technology relationships often diverge; while game studies focus on the player–avatar relationship, HCI emphasises sensory perception and stimulation. This paper bridges these perspectives by examining movement as fundamental to perception and interaction, exploring how movement unfolds in sequences between player(s) and technologies. The paper presents a theoretical framework that combines the neuroscientific theories of predictive processing and active inference with phenomenology to understand perception and experience as subjective experiences along with their underlying neurobiological processes. Complemented by an autoethnographic inquiry in which the primary author played seven games over three years, we apply the theoretical framework to analyse how movement drives embodied experiences. Our findings reveal that the composition of movement sequences is a key mechanism for embodied player experiences and technology relationships. Furthermore, the study identifies four dynamics in the sequential movement compositions that shape the qualities of experience. By foregrounding movement as central to connecting players and avatars in sensory engagement, we provide a unified perspective that benefits researchers and designers across the fields of game studies and human-computer interaction (HCI).

Designing superpowers in Human-Computer Interaction (HCI), often inspired by science fiction, has garnered increased attention. However, it is important to ask whether such superpower designs might have inherent negative side effects, especially considering that technological advances allow going beyond short demos to integrate these superpowers into everyday life. To understand the positive and negative side effects of superpower design, we created "EmoPals"and studied it in everyday life. EmoPals is a novel system inspired by telepathy, where one user's emotions are detected through a brain-computer interface and replicated on the other user's face through electrical muscle stimulation, therefore one user's happiness makes the other smile and vice versa. A 5-day field study with 12 participants suggests that EmoPals can strengthen emotional connections and facilitate empathy, however, it also highlights the negative side effects of amplifying negative emotions and social discomfort. We propose five design recommendations for designing superpowers that account for negative side effects. Ultimately, we aim to deepen our understanding of superpower design for everyday life.

DIS ’25, Funchal, Portugal

While interest in blending sound with culinary experiences has grown in Human-Food Interaction (HFI), the significance of food's material properties in shaping sound-related interactions has largely been overlooked. This paper explores the opportunity to enrich the HFI experience by treating food not merely as passive nourishment but as an integral material in computational architecture with input/output capabilities. We introduce “Sonic Delights,” where food is a comestible auditory-gustatory interface to enable users to interact with and consume digital sound. This concept redefines food as a conduit for interactive auditory engagement, shedding light on the untapped multisensory possibilities of merging taste with digital sound. An associated study allowed us to articulate design insights for forthcoming HFI endeavors that seek to weave food into multisensory design, aiming to further the integration of digital interactivity with the culinary arts.

Figure 1: We review and categorize VMIs aimed at enhancing context awareness.Our key contribution is a Macro-Micro-Macro level (whole-detail-whole) system design framework, providing actionable references from a Data Modality-Driven perspective: (1) Macro-level contextual factors: considerations for context understanding (Section 3); (2) Micro-level system foundations: input data modality (visual + other modalities), data integration stages, multimodal data processing and evaluation strategies (Sections 4, 5); (3) Macro-level design synthesis: application domains, design considerations and key challenges (Sections 6, 7).

1. Within HCI, there appears to be an interest in the human-computer integration paradigm (Farooq & Grudin, 2016; Grudin et al., 2018; Mueller et al., 2020), wherein computer and user form a close ...

Interactive technology has a complicated relationship with recreation in nature. Many people have praised, and many have lamented the impact of interactive technology on recreation in nature. Because nature recreation has important wellness benefits and interactive technology is likely to remain a part of nature recreation, there is a need to design interactive technology for nature recreation. Unfortunately, little generalized knowledge exists on how to design such technology. We create new intermediate design knowledge for interactive technology in nature recreation by drawing from others’ work, our prior work, and specifically Borgmann and Verbeek’s philosophies of technology. Our contribution is a framework based on a decomposition of engagement into nine facets related to engagement with place, time, and community. Four examples demonstrate the descriptive and generative power of the framework. This framework may enable the creation of interactive systems that complement rather than compete with nature recreation and may better preserve the wellness benefits of nature recreation.

• Presents a two-dimensional design space around body schema and body image for playful bodily extensions. • Details designers’ experiences creating playful bodily extensions. • Articulates practical strategies for the design of future playful bodily extensions. Interaction designers are increasingly interested in physically extending people's bodies and emerging work shows the potential of such bodily extensions for play, one example being interactive fantasy ears for the Cosplay community. We interviewed five designers of four playful bodily extensions to better understand how to design them. Based on their insights and our examination of prior work, we argue that such extensions can be characterized by the extent to which they alter the wearer's body schema and body image. We illustrate this characterization using a two-dimensional design space. We use this design space to articulate practical strategies for the design of future playful bodily extensions. Ultimately, we hope to bring more playful experiences to people's lives.

Cycling Human-Computer Interaction (CyclingHCI) refers to the study and design of user interfaces and interactions between bicycles and riders in the context of cycling-related experiences. To date, however, there has yet to be a structured agenda for CyclingHCI to clarify the immediate challenges researchers should address next and facilitate the advancement of the field. We, three CyclingHCI researchers who collectively designed, developed, evaluated 18 CyclingHCI projects, reflected on our experiences to derive 10 grand challenges that we articulate with design opportunities and considerations grouped into: (1) Pushing the technological boundaries for cycling, (2) Understanding and protecting cyclists, and (3) Spatially situated cycling interaction. Our findings provide practical implications for research and practice in CyclingHCI, with which we aim to enrich the cycling experience through the safe integration of technology.

Traditional games like "Tag" rely on shared control via inter-body interactions (IBIs) – touching, pushing, and pulling – that foster emotional and social connection. Digital games largely limit IBIs, with players using their bodies as input to control virtual avatars instead. Our “Shared Bodily Fusion” approach addresses this by fusing players’ bodies through a mediating computer, creating a shared input and output system. We demonstrate this approach with "Hidden Touch", a game where a novel social electrical muscle stimulation system transforms touch (input) into muscle actuations (output), facilitating IBIs. Through a study (n=27), we identified three player experience themes. Informed by these findings and our design process, we mapped their trajectories across our three experiential spaces – threshold, tolerance, and precision – which collectively form our design framework. This framework facilitates the creation of future digital games where IBIs are intrinsic, ultimately promoting the many benefits of social play.

The pleasure that often comes with eating can be further enhanced with intelligent technology, as the field of human-food interaction suggests. However, knowledge on how to design such pleasure-supporting eating systems is limited. To begin filling this knowledge gap, we designed “GustosonicSense”, a novel gustosonic eating system that utilizes wireless earbuds for sensing different eating and drinking actions with a machine learning algorithm and trigger playful sounds as a way to facilitate pleasurable eating experiences. We present the findings from our design and a study that revealed how we can support the "stimulation", "hedonism", and "reflexivity" for playful human-food interactions. Ultimately, with our work, we aim to support interaction designers in facilitating playful experiences with food.

The emerging concept of “computational food” focusing on the material affordances when designing food interactions is gaining traction in Human-Food Interaction (HFI). However, prior HFI research has not yet substantively investigated the dynamic nature of computational food from its creation to consumption, limiting our understanding of the complex interactions among creators, computational food, and consumers. In response, our paper shifts the perspective towards the dynamics of computational food interactions through a study in cooperation with chefs and gastronomists. Utilizing “Dancing Delicacies” as a research artifact – a system that facilitates dynamic dining trajectories – we adopted the concept of “choreography” to unravel the experiential dynamics of computational food. Our study resulted in six themes concerning computational food experiences and detailed four design implications central to culinary choreography. Our work aspires to leverage the choreographic potential of computational food design, paving the way for future HFI innovations.

The field of Sports Human-Computer Interaction (SportsHCI) investigates interaction design to support a physically active human being. Despite growing interest and dissemination of SportsHCI literature over the past years, many publications still focus on solving specific problems in a given sport. We believe in the benefit of generating fundamental knowledge for SportsHCI more broadly to advance the field as a whole. To achieve this, we aim to identify the grand challenges in SportsHCI, which can help researchers and practitioners in developing a future research agenda. Hence, this paper presents a set of grand challenges identified in a five-day workshop with 22 experts who have previously researched, designed, and deployed SportsHCI systems. Addressing these challenges will drive transformative advancements in SportsHCI, fostering better athlete performance, athlete-coach relationships, spectator engagement, but also immersive experiences for recreational sports or exercise motivation, and ultimately, improve human well-being.

People with a fear of being in water rarely engage in water activities and hence miss out on the associated health benefits. Prior research suggested virtual exposure to treat fears. However, when it comes to a fear of being in water, virtual water might not capture water’s immersive qualities, while real water can pose safety risks. We propose extended reality to combine both advantages: We conducted a study (N=12) where participants with a fear of being in water interacted with playful water-inspired virtual reality worlds while floating inside a floatation tank. Our findings, supported quantitatively by heart rate variability and qualitatively by interviews, suggest that playful extended reality could mitigate fear responses in an entertaining way. We also present insights for the design of future systems that aim to help people with a fear of being in water and other phobias by using the best of the virtual and physical worlds.

Recent combinations of interactive technology, humans, and water have resulted in “WaterHCI”. WaterHCI design seeks to complement the many benefits of engagement with the aquatic domain, by offering, for example, augmented reality systems for snorkelers, virtual reality in floatation tanks, underwater musical instruments for artists, robotic systems for divers, and wearables for swimmers. We conducted a workshop in which WaterHCI experts articulated the field's grand challenges, aiming to contribute towards a systematic WaterHCI research agenda and ultimately advance the field.

Underlying humanity’s social abilities is the brain’s capacity to interpersonally synchronize. Experimental, lab-based neuropsychological studies have demonstrated that inter-brain synchrony can be technologically mediated. However, knowledge in deploying these technologies in-the-wild and studying their user experience, an area HCI excels in, is lacking. With advances in mobile brain sensing and stimulation, we identify an opportunity for HCI to investigate the in-the-wild augmentation of inter-brain synchrony. We designed “PsiNet,” the first wearable brain-to-brain system aimed at augmenting inter-brain synchrony in-the-wild. Participant interviews illustrated three themes that describe the user experience of modulated inter-brain synchrony: hyper-awareness; relational interaction; and the dissolution of self. We contribute these three themes to assist HCI theorists’ discussions of inter-brain synchrony experiences. We also present three practical design tactics for HCI practitioners designing inter-brain synchrony, and hope that our work guides a HCI future of brain-to-brain experiences which fosters human connection.

Technology-facilitated “superpowers” are a popular topic in human-computer interaction, providing people with the experience of having superhero-like fantastic abilities. However, science fiction literature tells us that superpowers can also be unfortunate. We designed Wi-Fi Twinge, a system that uses electrical muscle stimulation to extend human perception to sense unseen Wi-Fi signals, giving people an allergy-like twinge reaction to Wi-Fi: a superpower that can be seen as unfortunate while also having potential benefits. Through an in-the-wild study, interviews with 12 participants revealed that although the superpower from Wi-Fi Twinge induced negative feelings and impacted certain day-to-day activities, it improved awareness of self and the surrounding environment. We used these results to offer design tactics for creating future superpower systems that consider potential unfortunate side effects. Ultimately, we aim to advance our understanding of technology-facilitated superpowers.

Prior research around the design of interactive systems has highlighted the benefits of supporting embodiment in everyday life. This resulted in the creation of body-centric systems that leverage movement. However, these advances supporting movement in everyday life, aligning with the embodiment theory, so far focused on sensing movement as opposed to facilitating movement. We present PneuMa, a novel wearable system that can facilitate movement in everyday life through pneumatic-based bodily extensions. We showcase the system through three examples: "Pardon?", moving the ear forward; "Greetings", moving a hand towards the "Bye-bye" gesture; "Take a break", moving the hands away from the keyboard, enabling the bodily extensions that support movement in everyday life. From the thematic analysis of a field study with 12 participants, we identified three themes: bodily awareness, Perception of the scenarios, and anticipating movement. We discuss our findings in relation to prior research around bodily extensions and embodied interaction to provide strategies to design bodily extensions that support movement in everyday life. Ultimately, we hope that our work helps more people profit from the benefits of everyday movement support.

This studio aims to collaboratively build foot augmentations, experiment with different materials and techniques, and create new designs for low-cost, wearable, and accessible devices that can be used by researchers, makers, designers, and artists. Considering the heightened focus on the human body with the rise of AR/VR/XR technologies, foot augmentation has great potential. To explore this potential, we invite researchers, designers and artists to share their applications, experiences, and ideas while designing foot augmentations. Participants will share knowledge, brainstorm ideas, and explore tools and materials for rapid prototyping. Finally, they will tinker and explore, discussing their design strategies to derive common approaches and best practices. Based on the hands-on session results, we will write a paper on design strategies for foot augmentation that will help facilitate more sustainable investigations and design of future foot interfaces.

There is an increasing interest in combining interactive technology with food, leading to a new research area called human-food interaction. While food experiences are increasingly benefiting from interactive technology, for example in the form of food tracking apps, 3D-printed food and projections on dining tables, a more systematic advancement of the field is hindered because, so far, there is no comprehensive articulation of the grand challenges the field is facing. To further and consolidate conversations around this topic, we invited 21 HFI experts to a 5-day seminar. The goal was to review our own and prior work to identify the grand challenges in human-food interaction. The result is an articulation of 10 grand challenges in human-food interaction across 4 categories (technology, users, design and ethics). By presenting these grand challenges, we aim to help researchers move the human-food interaction research field forward.

Contemporary human-food interaction design is often a technology-driven endeavor in which food's materiality has been largely underexplored. Building on the concept of “computational food”, this paper explores the design of food as a material realization of computation through a material-centered approach. We engaged with a “Research through Design” exploration by designing a computational food system called “Dancing Delicacies”, which enables food items to be “programmed” and “reconfigured” within dynamic trajectories. Our practice led to a design framework resulting in four original dish designs. Our dishes aim to illustrate the richness of this new design space for computational food. Furthermore, through engaging with expert practitioners from the hospitality industry, we provide a first account of understanding the design of computational food for dynamic dining trajectories and its speculative use contexts in the industry. With this work, we hope to inspire researchers and designers to envision a new future of human-food interaction.

Our bodies play an important part in our remembering practices, for example when we can remember passwords by typing, even if we cannot verbalise them. An increasing number of technologies are being developed to support remembering. However, so far, they seem to have not taken the opportunity yet to support remembering through bodily movements. To better understand how to design for such embodied remembering, we conducted a diary study with 12 participants who recorded their embodied remembering experiences in everyday life over a three-week period. Our thematic analysis of the diaries and interviews led to the creation of a framework that helps understand embodied remembering experiences (ERXs) based on the level of skilled and conscious movements used. We describe how this ERX framework could help with the design of technologies to support embodied remembering.

Interactive technologies offer novel opportunities for physically extending our bodies, with the most prominent examples being prosthetics along with systems emerging from the wearables community. However, most such systems appear to focus on instrumental benefits, missing out on the opportunity to use bodily extensions for play and its associated benefits (including a lower adoption barrier and the potential to reveal a broader understanding of such technologies). To begin understanding the design of playful bodily extensions, we interviewed five designers of bodily extensions that have been showcased in prestigious academic venues or turned into commercial products. Here we present themes and actionable advice from these interviews for the design of playful bodily extensions through a thematic analysis. Our work aims to support the design of future playful bodily extensions while promoting the experiential qualities of bodily extension design, with the ultimate goal of bringing more playful experiences to people’s lives.

Sleep plays a paramount role in maintaining healthy bodily functioning. Yet, poor sleep is an increasingly prevalent global health concern. Most current sleep technology tracks sleep, but how to design for promoting sleep is relatively underexplored. We highlight the potential of employing closed-loop systems for promoting sleep onset and explore this through the design and study of “Dozer”, a closed-loop beanie that accelerates sleep onset through auditory and electrical brain stimulation after detecting drowsiness in EEG. In an in-the-wild study, participant interviews revealed three UX themes (closed-loop neurocentric agency, awareness of hardware, and awareness of feedback), which ultimately suggested that participants fell asleep in spite of Dozer, rather than through its assistance. We interpret these results and provide actionable design tactics to inform the design of closed-loop sleep systems moving forward. We hope this work gives rise to a deeper understanding of designing closed techno-physiological loops.

Water's pleasant nature and associated health benefits have captivated the interest of HCI researchers. Prior WaterHCI work mainly focused on advancing instrumental applications, such as improving swimming performance, and less on designing systems that support interacting with technology in water in more playful contexts. In this regard, we propose floatation tanks as research vehicles to investigate the design of playful interactive water experiences. Employing somaesthetic design, we developed a playful extended reality floatation tank experience: "Fluito". We conducted a 13-participant study to understand how specific design features amplified participants' water experiences. We used a postphenomenological lens to articulate eight strategies useful for designers aiming to develop digital playful experiences in water, such as designing to call attention to the water and designing to encourage breathing and body awareness in water experiences. Ultimately, we hope that our work supports people to be playful and benefit from the many advantages of being in water.

Most digital bodily games focus on the body as they use movement as input. However, they also draw the player’s focus away from the body as the output occurs on visual displays, creating a divide between the physical body and the virtual world. We propose a novel approach – the "Body as a Play Material" – where a player uses their body as both input and output to unify the physical body and the virtual world. To showcase this approach, we designed three games where a player uses one of their hands (input) to play against the other hand (output) by loaning control over its movements to an Electrical Muscle Stimulation (EMS) system. We conducted a thematic analysis on the data obtained from a field study with 12 participants to articulate four player experience themes. We discuss our results about how participants appreciated the engagement with the variety of bodily movements for play and the ambiguity of using their body as a play material. Ultimately, our work aims to unify the physical body and the virtual world.

Spectating digital games can be exciting. However, due to its vicarious nature, spectators often wish to engage in the gameplay beyond just watching and cheering. To blur the boundaries between spectators and players, we propose a novel approach called "Fused Spectatorship", where spectators watch their hands play games by loaning bodily control to a computational Electrical Muscle Stimulation (EMS) system. To showcase this concept, we designed three games where spectators loan control over both their hands to the EMS system and watch them play these competitive and collaborative games. A study with 12 participants suggested that participants could not distinguish if they were watching their hands play, or if they were playing the games themselves. We used our results to articulate four spectator experience themes and four fused spectator types, the behaviours they elicited and offer one design consideration to support each of these behaviours. We also discuss the ethical design considerations of our approach to help game designers create future fused spectatorship experiences.

Ingestible sensors have become smaller and more powerful and allow us to envisage new human-computer interactions and bodily play experiences inside our bodies. Users can swallow ingestible sensors, which facilitate interior body sensing functions that provide data on which play experiences can be built. We call bodily play that uses ingestible sensors as play technologies “ingestible play”, and we have adopted a research-through-design (RtD) approach to investigate three prototypes. For each prototype, we conducted a field study to understand the player experiences. Based upon these results and practical design experiences, we have developed a design framework for ingestible play. We hope this work can guide the future design of ingestible play; inspire the design of play technologies inside the human body to expand the current bodily play design space; and ultimately extend our understanding of how to design for the human body by considering the bodily experience of one’s interior body.

Human–computer integration is an HCI trend in which computational machines can have agency, i.e., take control. Our work focuses on a particular form of integration in which the user and the computational machine share agency over the user's body, that is, can simultaneously (in contrast to a traditional turn-taking approach) control the user's body. The result is a user experience where the agency of the user and the computational machine is so intertwined that it is often no more discernable who contributed what to what extent; we call this “intertwined integration”. Due to the recency of advanced technologies enabling intertwined integration systems, we find that little understanding and documented design knowledge exist. To begin constructing such an understanding, we use three case studies to propose two key dimensions (“awareness of machine's agency” and “alignment of machine's agency”) to articulate a design space for intertwined integration systems. We differentiate four roles that computational machines can assume in this design space (angel, butler, influencer, and adversary). Based on our craft knowledge gained through designing such intertwined integration systems, we discuss strategies to help designers create future systems. Ultimately, we aim at advancing the HCI field's emerging understanding of sharing agency.

Brain-computer interface (BCI) systems hold the potential to foster human flourishing and self-actualization. However, we believe contemporary BCI system design approaches unnecessarily limit these potentialities as they are approached from a traditional interaction perspective, producing command-response experiences. This article proposes to go beyond “interaction” and toward a paradigm of human-computer integration. The potential of this paradigm is demonstrated through three prototypes: Inter-Dream, a system that integrates with the brain's autonomic physiological processes to drive users toward healthy sleep states; Neo-Noumena, a system that integrates with the user's affective neurophysiology to augment the interpersonal communication of emotion; and PsiNet, a system that integrates interpersonal brain activity to amplify human connection. Studies of these prototypes demonstrate the benefits of the integration paradigm in realizing the multifaceted benefits of BCI systems, and this work presents the brain-computer integration framework to help guide designers of future BCI integrations.

Aquatic recreation encompasses a variety of water-based activities from which participants gain physical, mental, and social benefits. Although interactive technologies for supporting aquatic recreation activities have increased in recent years, the HCI community does not yet have a structured understanding of approaches to interaction design for aquatic recreation. To contribute towards such an understanding, we present the results of a systematic review of 48 papers on the design of interactive technology for aquatic recreation, drawn from the ACM, IEEE, and SPORTDiscus libraries. This review presents an aquatic recreation user experience framework that details problems and opportunities concerning water and HCI. Our framework brings us closer to understanding how technology can interact with users and the aquatic environment to enhance the existing recreational experiences that connect us to aquatic environments. We found that designers can elicit delight, enablement, challenge, and synergy in aquatic recreation experiences.

Virtual Reality (VR) installations using head-mounted displays (HMD) are becoming increasingly popular in public spaces. However, VR's immersive nature engages only the HMD wearer and excludes everyone else in the public space, and there is little design knowledge of how to engage those not wearing an HMD. To address this, we draw from our experiences of having designed seven public VR installations to present a design space around the dimensions of “agency” and “interest” with four user engagement frames to articulate twelve different user roles. To guide designers to support all roles and to transition users between those roles, we complement the design space with a set of design tactics for public VR installations. We hope that these combined contributions will help designers engage more people with VR installations so that ultimately more people benefit from what VR has to offer.

In recognition of food's significant experiential pleasures, culinary practitioners and designers are increasingly exploring novel combinations of computing technologies and food. However, despite much creative endeavors, proposals and prototypes have so far largely maintained a traditional divide, treating food and technology as separate entities. In contrast, we present a “Research through Design” exploration of the notion of food as computational artifact: wherein food itself is the material of computation. We describe the Logic Bonbon, a dessert that can hydrodynamically regulate its flavor via a fluidic logic system. Through a study of experiencing the Logic Bonbon and reflection on our design practice, we offer a provisional account of how food as computational artifact can mediate new interactions through a novel approach to food-computation integration, that promotes an enriched future of Human-Food Interaction.

Human–computer interaction (HCI) is increasingly interested in supporting exertion experiences so more people can benefit from physical activity. So far, most systems have focused on sensing and presenting information to the user via screens to support the exertion experience. Interestingly, emerging technology can also act on the exerting user's body based on sensed information, granting researchers the potential to develop technology that not only “presents” but also “acts” on information throughout an integrated exertion experience. As a result, design opportunities surrounding computing machinery as contextually aware exertion partners are now available. However, there are currently no frameworks to guide the design of human–computer integration in an exertion context. To contribute to closing this gap, we designed three eBike systems to investigate different forms of integration with the exerting user and we studied the resulting user experiences. Based on the results of these three case studies, we present the first framework, including associated design tactics, to offer guidance on how to design human–computer integration in an exertion context.

The HCI community has a rich history of finding new ways to engage people with data beyond the screen. With our work, we aim to expand the scope of how interaction design can engage people, arguing that “eating data” has the potential to allow people to experience “data as delight”. With reference to prior work and our design research findings, we discuss the advantages and the challenges of this approach to integrating data and food. We then identify four themes to guide the design of engagements with data through food: food form, food commensality, food ephemerality, and emotional response to food. Within these design themes, we articulate twelve insights for interaction designers to use when working on serving data as delight.

Interest in combining interactive play and the human body, using “bodily play” systems, is increasing. While these systems primarily prioritize a player's control over their bodily actions, we see intriguing possibilities in the pursuit of “limited control over the body” as an intriguing design resource for bodily play systems. In this paper, we use three of our bodily play systems to illustrate how designers can engage with limited control over the body by varying the player's degree of indirect control (for instance, via other bodily activity and external triggers). We also propose four strategies for employing limited control over the body: Exploration, Reflection, Learning and Embracement. We hope our own work and the strategies developed from it will assist designers to employ limited control over the body, ultimately helping people benefit from engaging their bodies through play.

Sexual consent has undergone a transformation toward an “enthusiastic” feminist model that emphasizes consent as an ongoing and voluntary process of negotiation and affirmation. This paper considers how such a model can advance understandings of consent in HCI research and design in relation to embodied interactions with emerging technologies that also occur outside of sexual interactions. We apply the popular “FRIES” model of sexual consent (Freely given, Reversible, Informed, Enthusiastic and Specific) to three areas of embodied interaction: 1) bodily-play interactions, 2) persuasive interactions with smart technologies, and 3) intimate interactions with anthropomorphized devices. Based on erotic play practices, we contribute a “TEASE” process guideline (Traffic lights, Establish ongoing dialogue, Aftercare, Safewords, and Explicate soft/hard limits) to advance consensual practice in HCI and develop implementation scenarios.

Drone Chi is a Tai Chi inspired human-drone interaction experience. As a design research project, situated within somaesthetic interaction design, where a central topic is cultivating bodily and sensory appreciation to improve one's quality of life. Drone Chi investigates the potential of autonomous micro-quadcopters as a design material for somaesthetic HCI. Through a quasi-chronological account of the design process, this pictorial articulates how the sensory experiences of Tai Chi were integrated into Drone Chi. Taking a slow and open-ended design research approach, we iteratively developed the project through somaesthetic, product design and engineering perspectives and drew heavily on design analogies and imagery for inspiration. This elevated the influence of the soma amongst narrow engineering parameters and usability requirements. This pictorial serves as a reflective resource for designers who are experimenting with merging their native discipline with someasthetic interaction design.

Imaging capsules are ingestible sensors that capture the video of one's gastrointestinal tract for medical diagnosis. We believe that the capsule's experiential perspective is often overlooked by associated medical applications. This work explores the design of this experiential perspective through combining imaging capsules with digital play. We designed a playful wearable system called "InsideOut", where users play with the real-time video of their gastrointestinal tract captured by an imaging capsule. Based on an in-the-wild study, we derived four themes articulating the play experiences and discussed key design implications to guide future playful designs using imaging capsules. Our research highlights the opportunity of using medical imaging technologies to enable intriguing bodily play experiences. Furthermore, such experiences can deepen the players' engagement with and understanding of their bodies, ultimately contributing to a more playful and humanized health care agenda.

Prior psychology studies have shown that eating ice cream increases happiness, while human-computer interaction work has shown that interactive technology can enrich the eating experience. We explore the opportunity to combine these two through WeScream!, a playful social gustosonic system we designed-social gustosonic referring to the link between the acts of eating and listening as part of a social multisensory experience. WeScream! consists of two interdependent ice-cream cones that allow users to interact with musical sounds generated through the act of eating ice cream together. We report on an in-the-wild study that highlights how our system facilitated a "hard fun" experience through eating together, increased participants' awareness of relatedness, and drew shared attention to the ice cream's taste via increased face-to-face interaction. Drawing on these study insights, we also present three design tactics to guide designers in designing future social gustosonic experiences. Ultimately, we aim to contribute to a playful future of social eating experiences, supporting people in enjoying eating together.

In this work we introduce peripheral awareness as a neurological state for real-time human-computer integration, where the human is assisted by a computer to interact with the world. Changes to the field of view in peripheral awareness have been linked with quality of human performance. This instinctive narrowing of vision that occurs as a threat is perceived has implications in activities that benefit from the user having a wide field of view, such as cycling to navigate the environment. We present "Ena", a novel EEG-eBike system that draws from the user's neural activity to determine when the user is in a state of peripheral awareness to regulate engine support. A study with 20 participants revealed various themes and tactics suggesting that peripheral awareness as a neurological state is viable to align human-machine integration with internal bodily processes. Ena suggests that our work facilitates a safe and enjoyable human-computer integration experience.

Somaesthetics - motivated by improving life quality via appreciation for bodily and sensory experiences - is increasingly influencing HCI designs. Investigating the potential of drones as a material for somaesthetic HCI, we designed Drone Chi: a Tai Chi-inspired close-range human-drone interaction experience. The design process for Drone Chi has been informed by the soma design approach and the Somaesthetic Appreciation concept from HCI literature. The artifact expands somaesthetic HCI by exemplifying dynamic and intimate somaesthetic interactions with a robotic design material, and body movements in expansive 3D space. To characterize the Drone Chi experience, we conducted an empirical study with 32 participants. Analysis of participant accounts revealed 4 themes that articulate different aspects of the experience: Looping Mental States, Environment, Agency vs. Control, and Physical Narratives. From these accounts and our craft knowledge, we derive 5 design implications to guide the development of movement-based close-range drone interactions.

Human-Computer Integration (HInt) is an emerging paradigm in which computational and human systems are closely interwoven. Integrating computers with the human body is not new. however, we believe that with rapid technological advancements, increasing real-world deployments, and growing ethical and societal implications, it is critical to identify an agenda for future research. We present a set of challenges for HInt research, formulated over the course of a five-day workshop consisting of 29 experts who have designed, deployed and studied HInt systems. This agenda aims to guide researchers in a structured way towards a more coordinated and conscientious future of human-computer integration.

The subjective experience of emotion is notoriously difficult to interpersonally communicate. We believe that technology can challenge this notion through the design of neuroresponsive systems for interpersonal communication. We explore this through "Neo-Noumena", a communicative neuroresponsive system that uses brain-computer interfacing and artificial intelligence to read one's emotional states and dynamically represent them to others in mixed reality through two head-mounted displays. In our study five participant pairs were given Neo-Noumena for three days, using the system freely. Measures of emotional competence demonstrated a statistically significant increase in participants' ability to interpersonally regulate emotions. Furthermore, participant interviews revealed themes regarding Spatiotemporal Actualization, Objective Representation, and Preternatural Transmission. We also suggest design strategies for future augmented emotion communication systems. We intend that work gives guidance towards a future in which our ability to interpersonally communicate emotion is augmented beyond traditional experience.

Inbodied interaction is an emerging area in HCI that aligns how the body performs internally with our designs to support and optimise human performance. Inbodied Interaction therefore relies on knowledge of our physiology/neurology/kinesiology etc, to blend with HCI methodology. Recent, Inbodied Interaction workshops and summer schools, have been designed to share models of these processes to accelerate access to these areas of specialisation for HCI researchers. As such this one-day-hands-on-studio presents an extension of this work - an Inbodied interaction framework - to (1) make inbodied sciences accessible and (2) usable for HCI practitioners when it comes to crafting experiences, whether for health, performance or play. Our framework also offers a design alternative to cyborging futures that seek to augment human performance, Inbodied Interaction seeks to help discover and optimise human potential. As such, in this studio, we will explore where inbodied interaction fits in the narrative of our future bodies.

There is an increasing trend in utilizing interactive technology for bodily integrations, such as additional limbs and ingestibles. Prior work on bodily integrated systems mostly examined them from a productivity perspective. In this article, we suggest examining this trend also from an experiential, playful perspective, as we believe that these systems offer novel opportunities to engage the human body through play. Hence, we propose that there is an opportunity to design "bodily integrated play". By relating to our own and other's work, we present an initial set of design strategies for bodily integrated play, aiming to inform designers on how they can engage with such systems to facilitate playful experiences, so that ultimately, people will profit from bodily play's many physical and mental wellbeing benefits even in a future where machine and human converge.

Bodily play systems are becoming increasingly prevalent, with research aiming to understand the associated player experience. We argue that a more nuanced lexicon describing "bodily play experience" can be beneficial to drive the field forward. We provide game designers with two German words to communicate two different aspects of experience: "Erfahrung", referring to experience where one is actively engaged in and gains knowledge from; and "Erlebnis", referring to a tacit experience often translated as "lived experience". We use these words to articulate a suite of design strategies for bodily play experiences by referring to past design work. We conclude by discussing these two aspects of experience in conjunction with two previously established perspectives on the human body. We believe this more nuanced lexicon can provide a clearer understanding for designers about bodily play allowing them to guide players in gaining the many benefits from such experiences.

There is an increasing trend in HCI to combine eating and technology. We highlight the potential of interactive technology to support an experiential perspective on eating, in particular, how interactive technology can support experiencing eating as play. To understanding this, we reflect on four playful interactive eating systems we designed and two other works to articulate five strategies: make eating challenging, break cultural norms, design across eating stages, reduce eating autonomy, and playfully extend the social aspect. For each, we also include practical implementation options to provide designers with initial guidance on how they can begin to support experiencing eating as play. Ultimately, with our work, we aim to facilitate a future where eating is more playful.

Many people enjoy “vertigo” sensations caused by intense playful bodily activities such as spinning in circles, and riding fairground rides. Game scholar Caillois calls such experiences “vertigo play,” elucidating that these enjoyable activities are a result of confusion between sensory channels. In HCI, designers are often cautious to avoid deliberately causing sensory confusion in players, but we believe there is an opportunity to transition and extend Caillois’ thinking to the digital realm, allowing designers to create novel and intriguing digital bodily experiences inspired by traditional vertigo play activities. To this end, we present the Digital Vertigo Experience framework. Derived from four case studies and the development of three different digital vertigo experiences, this framework aims to bring the excitement of traditional vertigo play experiences to the digital world, allowing designers to create more engaging and exciting body-based games, and provides players with more possibilities to enjoy novel and exciting play experiences.

Self-monitoring devices are becoming increasingly popular in the support of physical activity experiences. These devices mostly represent on-screen data using numbers and graphs and in doing so, they may miss multi-sensorial methods for engaging with data. Embracing the opportunity for pleasurable interactions with one's own data through the use of different materials and digital fabrication technology, we designed and studied three systems that turn this data into 3D-printed plastic artifacts, sports drinks, and 3D-printed chocolate treats. We utilize the insights gained from associated studies, related literature, and our experiences in designing these systems to develop a conceptual framework, “ Shelfie. ” The “ Shelfie ” framework has 13 cards that convey key themes for creating material representations of physical activity data. Through this framework, we present a conceptual understanding of relationships between material representation and physical activity data and contribute guidelines to the design of meaningful material representations of physical activity data.

Theme parks visits can be very playful events for families, however, waiting in the ride’s queues can often be the cause of great frustration. We developed a novel augmented reality game to be played in the theme park’s queue, and an in-the-wild study with X participants using log data and interviews demonstrated that every minute playing was perceived to the same extent of about 5 minutes of not playing the game. We articulate a design space for researchers and strategies for game designers aiming to reduce perceived waiting time in queues. With our work, we hope to extend how we use games in everyday life to make our lives more playful.

Researchers are increasingly exploring interactive technology supporting human-system partnership in an exertion context, such as cycling. So far, most investigations have supported the rider cognitively, by the system "sensing and presenting" information to assist the rider to make informed decisions. In contrast, we propose systems that promote user-system co-operation, by "sensing and acting" on information to assist the rider, not only "cognitively" but also "physically", with the aim of facilitating user-system co-operation in an exertion context. Our prototype, "Ari", is a novel augmented eBike designed to facilitate user-system co-operation, where the information that each party can sense is used in regulating the speed to cross all traffic lights on green. A study with 20 bike riders resulted in five themes and six design tactics to further the design of interactive systems at the intersection of human-computer integration in an exertion context, thereby facilitating user-system co-operation to augment the exertion experience.

Playing with computers mostly means focusing on the mind, rather than the body. However, children's play teaches us how powerful experiences can be if the human body is involved. In consequence, I propose to see the body as a design opportunity for unique human-computer interactions, this enables us to "experience our bodies as play". Drawing on phenomenology to unpack what we mean by "body" and "experience", I argue that designing technology for the human body, whether for young children, teens or adults, is uniquely different than designing for keyboard or touch. As such, I propose to put the human body into the center of the digital play experience. I illustrate this thinking by presenting recent work that puts the human body into the center of the digital play experience, including a flying robot as jogging companion, family games for children in hospital, 3D printed heart rate souvenirs, shared reading apps, illuminated bicycle helmets, on-body robotic arms, wireless pills and singing ice cream.

Ingestible sensors are pill-like sensors that people swallow mainly for medical purposes. We propose that ingestible sensors also offer unique opportunities to facilitate intriguing bodily experiences in a playful manner. To explore this, we present "HeatCraft", a two-player system that translates the user's body temperature measured by an ingestible sensor to localized thermal stimuli delivered through a waist belt equipped with heating pads. We conducted a study with 16 participants. The study revealed three design themes (Integration of body and technology, Integration of internal body and outside world, and Integration of play and life) along with some open challenges. In summary, this work contributes knowledge to the future design of playful experiences with ingestible sensors.

Recent HCI work on digital games highlighted the advantage for designers to take on a 1st person perspective on the human body (referring to the phenomenological "lived" body) and a 3rd person perspective (the material "fleshy" body, similar to looking in the mirror). This is useful when designing bodily play, however, we note that there is not much game design discussion on the 2nd person social perspective that highlights the unique interplay between human bodies. To guide designers interested in supporting players to experience their bodies as play, we describe how game designers can engage with the 2nd person social perspective through a set of design tactics based on four of our own play systems. With our work, we hope we can aid designers in embracing this 2nd person perspective so that more people can benefit from engaging their bodies through games and play.

Poor sleep has been acknowledged as an increasingly prevalent global health concern, however, how to design for promoting sleep is relatively underexplored. We propose neurofeedback technology may potentially facilitate restfulness and sleep onset, and we explore this through the creation and study of "Inter-Dream", a novel multisensory interactive artistic experience driven by neurofeedback. Twelve participants individually rested, augmented by Inter-Dream. Results demonstrated: statistically significant decreases in pre-sleep cognitive arousal (p = .01), negative emotion (p = .008), and negative affect (p = .004). EEG readings were also indicative of restorative restfulness and cognitive stillness, while interview responses described experiences of mindfulness and playful self-exploration. Taken together, our work highlights neurofeedback as a potential pathway for future research in the promotion of sleep, while also suggesting strategies for designing towards this within the context of pre-sleep.

Although virtual reality hardware is now widely available, the uptake of real walking is hindered by the fact that it requires often impractically large amounts of physical space. To address this, we present VirtualSpace, a novel system that allows overloading multiple users immersed in different VR experiences into the same physical space. VirtualSpace accomplishes this by containing each user in a subset of the physical space at all times, which we call tiles; app-invoked maneuvers then shuffle tiles and users across the entire physical space. This allows apps to move their users to where their narrative requires them to be while hiding from users that they are confined to a tile. We show how this enables VirtualSpace to pack four users into 16m2. In our study we found that VirtualSpace allowed participants to use more space and to feel less confined than in a control condition with static, pre-allocated space.

Games research in HCI is continually interested in the human body. However, recent work suggests that the field has only begun to understand how to design bodily games. We propose that the games research field is advancing from playing with digital content using a keyboard, to using bodies to play with digital content, towards a future where we experience our bodies as digital play. To guide designers interested in supporting players to experience their bodies as play, we present two phenomenological perspectives on the human body (Körper and Leib) and articulate a suite of design tactics using our own and other people's work. We hope with this paper, we are able to help designers embrace the point that we both "have" a body and "are" a body, thereby aiding the facilitation of the many benefits of engaging the human body through games and play, and ultimately contributing to a more humanized technological future.

Interactive storybooks, such as those available on the iPad, offer multiple ways to convey a story, mostly through visual, textual and audio content. How to effectively deliver this combination of content so that it supports positive social and educational development in pre-literate children is relatively underexplored. In order to address this issue we introduce the "Counterpointed Triad Technique". Drawing from traditional literary theory we design visual, textual and audio content that each conveys different aspects of a story. We explore the use of this technique through a storybook we designed ourselves called "How Far Is Up?". A study involving 26 kindergarten children shows that "How Far Is Up?" can engage pre-literature children while they are reading alone and also when they are reading with an adult. Based on our craft knowledge and study findings, we present a set of design strategies that aim to provide designers with practical guidance on how to create engaging interactive digital storybooks.

"You Better Eat to Survive" is a two-player virtual reality game that involves eating real food to survive and ultimately escape from a virtual island. We sense eating actions of players by analyzing chewing sounds captured by a low-cost microphone attached to the players cheek. Our interest in using cooperative eating as a way of interacting in virtual reality is driven by the possibilities of creating a cross-modal gameplay experience that benefits social interactions. A user study with 22 players showed that eating real food improved players feeling of presence, challenged trust dependencies and made the survival aspect of the game feel more "real". We use these insights to articulate three design themes that can guide designers in creating virtual reality games that incorporate cooperative eating. Ultimately, our work aims to guide design thinking towards using underexplored interaction methods in virtual reality games, thereby reiterating the post-digital design theme of TEI 2018.

Reinforcement learning (RL) is a machine learning paradigm behind many successes in games, robotics, and control applications. RL agents improve through trial-and-error, therefore undergoing a learning phase during which they perform suboptimally. Research effort has been put into optimizing behavior during this period, to reduce its duration and to maximize after-learning performance. We introduce a novel algorithm that extracts useful information from expert demonstrations (traces of interactions with the target environment) and uses it to improve performance. The algorithm detects unexpected decisions made by the expert and infers what goal the expert was pursuing. Goals are then used to bias decisions while learning. Our experiments in the video game Pac-Man provide statistically significant evidence that our method can improve final performance compared to a state-of-the-art approach.

Self-monitoring offers benefits in facilitating awareness about physical exercise, but such data-centric activity may not always lead to an enjoyable experience. We introduce EdiPulse a novel system that creates activity treats to offer playful reflections on everyday physical activity through the appealing medium of chocolate. EdiPulse translates self-monitored data from physical activity into small 3D printed chocolate treats. These treats (< 20 grams of chocolate in total) embody four forms: Graph, Flower, Slogan and Emoji. We deployed our system across 7 households and studied its use with 13 participants for 2 weeks per household. The field study revealed positive aspects of our approach along with some open challenges, which we disseminate across five themes: Reflection, Positivity, Determination, Affection, and Co-experience. We conclude by highlighting key implications of our work for future playful food-based technology design in supporting the experience of being physically active

The field of HCI has increasingly looked at ways to support the physically active human being, however, new work suggests that the field has only begun to understand the many virtues of exertion. To further the field, we present a set of five design lenses extended primarily from sports philosophy literature to help approach exertion not just as a means of deferring death, but also as an opportunity for personal growth. The lenses facilitate learning how to appreciate a void (Reverie), welcome pleasure (Pleasure), become humble (Humility), as well as be fearful and excited simultaneously (Sublime), whilst being more carefully aware of one's own body (Oneness). Using these lenses, we articulate associated technology opportunities through related work as well as our own craft knowledge. With our work, we aim to support designers who want to facilitate the many virtues of exertion so that ultimately more people profit from the many benefits of being physically active.

While exertion games facilitate, and benefit from, social play, most exertion games merely support players acting independently. To help designers explore the richness of social play in exertion games, we present the design dimension “bodily interplay” that gives critical focus to how players’ bodies interact with one another. We offer two broad categories of bodily interplay— parallel and interdependent play —to explain how exertion games can facilitate independent and offensive/defensive-type experiences. These categories can be applied to both the physical and virtual space, and by looking at all permutations of these categories, we articulate four ways of coupling the spaces: comparative, actuated, derived, and projected coupling. This article illustrates the inspirational power of the dimensions by applying them to the analysis of four exertion games. Altogether, we articulate a vocabulary that can guide designers in the creation of social exertion games, helping players profit from the many benefits of exertion.

Sports fans are increasingly using social media platforms like Twitter to express emotions and share their opinions while watching sports on TV. These commentaries describe a intense subjective experience of a fan watching a sport passionately. We see an opportunity to attend to these nostalgic moments by capturing them into a physical form. We present, Fantibles, personalized sports memorabilia that highlights an individual's commentary about sports on Twitter along with the uniqueness of each sports match. As a first case study, we investigate Fantibles for one popular sport, Cricket. We report insights from field deployments of Fantibles during an ODI Cricket match series between India and Bangladesh and offer reflections on the design in the form of four themes: self-expression, layered sense making, ad-hoc interactions and distributed social interactions. We believe our work opens up new interaction possibilities to support social sports viewing experience and design thinking on creating personalized sports memorabilia.

The use of technology while being mobile now takes place in many areas of people's lives in a wide range of scenarios, for example users cycle, climb, run and even swim while interacting with devices. Conflict between locomotion and system use can reduce interaction performance and also the ability to safely move. We discuss the risks of such "interaction in motion", which we argue make it desirable to design with locomotion in mind. To aid such design we present a taxonomy and framework based on two key dimensions: relation of interaction task to locomotion task, and the amount that a locomotion activity inhibits use of input and output interfaces. We accompany this with four strategies for interaction in motion. With this work, we ultimately aim to enhance our understanding of what being "mobile" actually means for interaction, and help practitioners design truly mobile interactions.

Using game balancing techniques can provide the right level of challenge and hence enhance player engagement for sport players with different skill levels. Digital technology can support and enhance balancing techniques in sports, for example, by adjusting players' level of intensity based on their heart rate. However, there is limited knowledge on how to design such balancing and its impact on the user experience. To address this we created two novel balancing techniques enabled by digitally augmenting a table tennis table. We adjusted the more skilled player's performance by inducing two different styles of play and studied the effects on game balancing and player engagement. We showed that by altering the more skilled player's performance we can balance the game through: (i) encouraging game mistakes, and (ii) changing the style of play to one that is easier for the opponent to counteract. We outline the advantages and disadvantages of each approach, extending our understanding of game balancing design. We also show that digitally augmenting sports offers opportunities for novel balancing techniques while facilitating engaging experiences, guiding those interested in HCI and sports.

Q-learning associates states and actions of a Markov Decision Process to expected future reward through online learning. In practice, however, when the state space is large and experience is still limited, the algorithm will not find a match between current state and experience unless some details describing states are ignored. On the other hand, reducing state information affects long term performance because decisions will need to be made on less informative inputs. We propose a variation of Q-learning that gradually enriches state descriptions, after enough experience is accumulated. This is coupled with an ad-hoc exploration strategy that aims at collecting key information that allows the algorithm to enrich state descriptions earlier. Experimental results obtained by applying our algorithm to the arcade game Pac-Man show that our approach significantly outperforms Q-learning during the learning process while not penalizing long-term performance.

HCI is increasingly interested in supporting people's physically active lifestyle. Adventure is part of this lifestyle, and to contribute an HCI perspective on adventure, we present an autoethnographical account of an expedition via Nepal to Mt. Everest. During this expedition, on the 25th and 26th April 2015, two devastating earthquakes struck the region. We believe we can learn from such extreme experiences and therefore reflect on this epic adventure through a set of themes to articulate two dimensions (expected-unexpected and instrumental-experiential) in order to identify four roles for adventure-technology: as coach, rescuer, documentarian and mentor. Our work aims to provide HCI designers with an initial conceptual lens to embrace adventure, and more generally, to expand our knowledge of supporting people's physically active lifestyle.

Vertigo can be described as an attempt to momentarily destroy the stability of perception and inflict a kind of voluptuous panic upon an otherwise lucid mind. Vertigo has, however, not been generally considered as a design resource and we believe it to be under-explored in the area of digital bodily play. To investigate how vertigo could be considered as a design resource in this context, we conducted a review of relevant literature and held a design workshop with nine students to explore the potential of vertigo as a design resource for digital bodily play. From our exploration we identify five key design themes that designers might consider when designing a Vertigo Experience. Through this work we hope to encourage designers of bodily play experiences to consider vertigo as a design resource in their games.

Players sharing control of each other's bodies offers a promising direction for delivering engaging collaborative experiences in digital physical games. We present HandyFeet -- a movement based game platform in which two players compete to most effectively direct the body of a third player. This third person becomes like a puppet that has two masters. The two directing players take turns making hand signals to guide one of the puppet player's legs. The puppet-person is prevented from seeing both their own legs and the floor, and so is dependent upon the directors' instructions for navigating the physical environment. To further the development of movement based games involving players surrendering or sharing control of their own bodies, we offer five themes that arose from analysing our initial play-tests.

Many studies have shown that crowd-support, such as cheering during sport events, can have a positive impact on athletes' performance. However, up until recently this support was only possible if the supporters and the athletes were geographically co-located. Can cheering be done remotely and would this be effective? In this paper we investigate the effect and possibilities of live remote cheering on co-located athletes and online supporting crowds that have a weak social tie and no social tie with the athlete. We recruit 140 online spectators and 5 athletes for an ad-hoc 5km road race. Results indicate that crowds socially closer to the athletes are significantly more engaged in the support. The athletes were excited by live remote cheering from friendsourced spectators and cheering from unknown crowdsourced participants indicating that remote friends and outsourced spectators could be an important source of support.

Using game elements and mechanics in sports training holds great potential for increasing player enjoyment, but also introduces a risk of reducing training relevance. This paper describes a novel training installation for individual handball training, called "The Bouncer", and the design process behind three training games. In order to investigate how game elements can affect the training experience, we conducted a study with 10 experienced amateur handball players, eliciting responses regarding the training relevance of the games. Based on the study and our design insights, we propose three challenges that designers of interactive sports-training games need to consider: 1) Maintaining relevance when translating physical elements into digital representations. 2) Choosing an appropriate level of sensing as game input. 3) Introducing points in training exercises without reducing sport relevance. For the three challenges, we propose strategies to help future designers of training games.

In this paper, we introduce palatable representations that besides improving the understanding of physical activity through abstract visualization also provide an appetizing drink to celebrate the experience of being physically active. By designing such palatable representations, our aim is to offer novel opportunities for reflection on one's physical activities. We present TastyBeats, a fountain-based interactive system that creates a fluidic spectacle of mixing sport drinks based on heart rate data of physical activity, which the user can later consume to replenish the loss of body fluids due to the physical activity. We articulate our experiences in designing the system as well as learning gained through field deployments of the system in participants' homes for a period of two weeks. We found that our system increased participants' awareness of physical activity and facilitated a shared social experience, while the prepared drink was treated as a hedonic reward that motivated participants to exercise more. Ultimately, with this work, we aim to inspire and guide design thinking on palatable representations, which we believe opens up new interaction possibilities to support physical activity experience.

Jogging is a popular exertion activity. The abundance of jogging apps suggests to us that joggers can appreciate the opportunity for technology to support the jogging experience. We want to take this investigation a step further by exploring if, and how, robotic systems can support the jogging experience. We designed and built a flying robotic system, a quadcopter, as a jogging companion and studied its use with 13 individual joggers. By analyzing their experiences, we derived three design dimensions that describe a design space for flying robotic jogging companions: Perceived Control, Focus and Bodily Interaction. Additionally, we articulate a series of design tactics, described by these dimensions, to guide the design of future systems. With this work we hope to inspire and guide designers interested in creating robotic systems to support exertion experiences.

Visualizing heart rate on screen has become popular to measure physical activity performance and progress towards set health goals. However, we believe that this prevalent method of visualizing data often reduces the interaction to only reading of information. In response, we propose a new way of visualizing heart rate data through a public interactive water fountain installation we call, TastyBeats. TastyBeats engages participants in a fluidic spectacle by creating a personalized sports drink representing their heart rate data while serving the additional purpose of replenishing lost energy during physical activity. We present findings and three design strategies from the three exhibitions of this work to inform designers interested in using drinkable fluids to support the physical activity experience. Ultimately, with our work we aim to expand our understanding of the potential of interactive technology to support the energy-cycle when being physically active.

Movement-based digital games are becoming increasingly popular, yet there is limited comprehensive guidance on how to design these games. In this article we discuss a set of guidelines for movement-based game design that were initially presented at CHI 2014 (Mueller & Isbister, 2014). These guidelines were developed through reflection upon our research-based game development practice and then validated and refined through interviews with 14 movement-based game design experts with experience in the academic, independent, and commercial game development domains. In this article, we provide an in-depth contextualization and explanation of the research process that led to the creation of the final guidelines and discuss what human–computer interaction researchers and designers might learn from the guidelines beyond entertainment contexts. The primary contribution of this research is a body of generative intermediate-level knowledge (Höök & Löwgren, 2012) in the design research tradition that is readily accessible and actionable for the design of future movement-based games and other movement-based interfaces.

Playing exertion games with others can be engaging. However, players with different physical skill levels competing against each other can experience reduced engagement because they are either not challenged enough, or challenged too much. Balancing methods can address this; however, there is only limited understanding of balancing in exertion games. In this paper, we identify two distinct dimensional balancing techniques: "internal adjustment" and "external adjustment". We report results from a study where we measured player engagement after applying these adjustments to a digital table tennis game and the traditional table tennis game, finding two disengagement factors: "unexpected physical challenges" and "unacceptable competitive advantage". Based on these factors we derived a set of exertion game design considerations. We conclude that applying digital technology to a physical game can change the required skill level to play the game, and this can affect the impact of these adjustments on player engagement. These results enhances our understanding of balancing in exertion games, supporting the benefits of playing exertion games with others.

Digital games are increasingly profiting from sensing technologies. However, their focus is mostly on sensing limb movements. We propose that sensing capabilities could also be used to engage players with proxemics: the interpersonal distance between players. We further add that wireless networks offer complementary distance zones for designers, offering novel design resources for digital play. We use our own as well as other games to articulate a set of strategies on how designers can utilize both proxemics and the new wireless proxemics to facilitate novel play experiences. Ultimately, with our work, we aim to expand the range of digital play.

Movement-based digital games typically make it clear whose movement representation belongs to which player. In contrast, we argue that selectively concealing whose movement controls which representation can facilitate engaging play experiences. We call this "innominate movement representation" and explore this opportunity through our game "i-dentity", where players have to guess who makes everyone's controller light up based on his/her movements. Our work reveals five dimensions for the design of innominate movement representation: concealing the association between movement and representation; number of represented movements; number of players with representations; location of representation in relation to the body and technical attributes of representation. We also present five strategies for how innominate representation can be embedded into a play experience. With our work we hope to expand the range of digital movement games.

In this paper, we advocate a novel approach of representing physical activity in the form of material artifacts. By designing such material representations, we aim to understand what these artifacts might offer in terms of reflecting upon physical activity. For example, what types of affect do material artifacts, representing ones' physical activity create for the user' In order to advance this understanding, we designed a system called SweatAtoms that transforms the physical activity data based on heart rate into 3D printed material artifacts. We conducted an 'in the wild study' by deploying our system in six households where participants were experiencing five different material representations of their physical activity for a period of two weeks each. We found that the material artifacts made participants more conscious about their involvement in physical activity and illustrated different levels of engagement with the artifacts. Along with reporting the gained insights from the deployments, we offer reflections on designing material representations for physical activity. We hope that our work will inspire designers to consider new possibilities afforded by digital fabrication to support user's experience with physical activity by utilizing interactive technologies at our disposal.

Advances in sensing technologies have led to research into exertion games that support physically effortful experiences. Despite the existence of theoretical frameworks that can be used to analyze such exertion experiences, there are few tools to support the hands-on practice of exertion game design. To address this, we present a set of design cards based on the "Exertion Framework", grounded in our experience of creating exertion games for over a decade. We present results demonstrating the value and utility of these Exertion Cards based on our studies of their use in three workshops held over seven sessions with 134 design students and experts. We also articulate lessons learned from transforming a theoretical framework into a design tool that aims to support designers in their practice.

Movement-based digital games are becoming increasingly popular, yet there is limited comprehensive guidance on how to design these games. We present a set of guidelines for movement-based game design that has emerged from our research-based game development practice. These guidelines have been examined and refined by 14 movement-based game design experts with experience in the academic, independent and commercial game development domains. We contextualize the guidelines using current findings about movement-based game and interaction design, taken from both published research papers and game design venues. Our primary contribution is a body of generative intermediate-level knowledge in the design research tradition that is readily accessible and actionable for the design of future movement-based games.

Supporting physical exertion is a growing trend in digital technology design. However, most experiences focus on bodily actions in which participants act independently of each other. In contrast, we focus on virtual body-to-body interactions between multiple participants, inspired by combat-oriented sports such as boxing that highlight the need to act while avoiding reciprocal bodily action. Mediating such body-to-body interactions with technology is challenging, particularly when participants are not co-located. Prior systems have often involved a mixture of novel physical interfaces and interactions through virtual avatars. This paper charts a design space for virtual combat play experiences and offers a set of design dimensions and recommendations for future systems. We draw on our experiences of designing and evaluating Remote Impact - a boxing-style exertion game involving aggressive bodily interaction with a large force-sensing projection surface. By expanding our knowledge of mediated exertion with an understanding of combat interactions we extend the social experience space of exertion play.

Interactive technology is increasingly used to support physical activities. However, there is limited knowledge about how interactive technology should be designed to support trick-focused experiences such as skateboarding. We developed Copy Paste Skate, a novel multimodal feedback system, and studied its use by 21 avid skateboarders to explore the design of interactive technology for skateboarding. Based on observations and interviews we articulate two key design dimensions that highlight how designing for skateboarding means supporting execution quality of tricks as well as supporting the trick originality. We also present 4 design strategies to help designers support both dimensions in one integrated design. Our work extends designers' knowledge about how to design interactive technology for skateboarding, ultimately extending our understanding of how interactive technology can support people being physically active.

People often engage in physical activity with others, yet wearable technologies like heart rate monitors typically focus on individual usage. In response, we discuss the potential of heart rate displays in a social context, by means of an augmented cycling helmet that displays heart rate data. We studied how pairs of cyclists engaged with this setup and found that access to another person's heart rate data can result in social interplay which in turn supports engagement with the exertion activity. Through our design process and study, we reveal key dimensions of designing for social uses of heart rate data and wearable displays: temporal and spatial accessibility of data, technology support for its interpretation, and influences on heart rate. We also articulate a set of insights for designers that aim to support social exertion activities with heart rate data. As such, our work expands our understanding of wearable technologies' unique interaction opportunities.

Interactive technology can support exertion activities, with many examples focusing on improving athletic performance. We see an opportunity for technology to also support extreme sports such as skateboarding, which often focus primarily on the experience of doing tricks rather than on athletic performance. However, there is little knowledge on how to design for such experiences. In response, we designed 12 basic skateboarding prototypes inspired by skateboarding theory. Using an autoethnographical approach, we skated with each of these and reflected on our experiences in order to derive four design themes : location of feedback in relation to the skater's body, timing of feedback in relation to peaks in emotions after attempts, aspects of the trick emphasized by feedback, and aesthetic fittingness of feedback. We hope our work will guide designers of interactive systems for skateboarding, and extreme sports in general, and will therefore further our understanding of how to design for the active human body.

Interactive displays that aim to engage people through play have been successfully deployed in urban environments. However, there has been little work bringing interactive displays into existing public game spaces like outdoor basketball courts. To explore this, we designed an interactive display for a public half-court basketball hoop. We studied the impact of 3 different display modes over a 10-week period through interviews with players, spectators, and passers-by. Our findings suggest 3 dimensions for the design space of such interactive displays: balancing noticeability across different user groups, support for different play action, and support for connecting user groups. We also present 6 design tactics along these dimensions to help designers create engaging interactive displays for public game spaces. using it to facilitate engaging playful experiences.

Socially awkward experiences are often looked upon as something to be avoided. However, examples from the non-digital entertainment domain suggest that social awkwardness can also facilitate engaging experiences. Yet there has been little research into exploring social awkwardness in digital games. In response, we present Musical Embrace, a digital game that promotes close physical proximity through the use of a novel pillow-like controller to facilitate socially awkward play between strangers. Through our observations from demonstrating Musical Embrace at a number of events, we have derived a set of strategies to engage players by "facilitating social awkwardness", allowing players to "transform social awkwardness" while also letting players "take control of social awkwardness". With our work we hope to inspire game designers to consider the potential of social awkwardness in digital games and guide them when using it to facilitate engaging play experiences.

Exercising with others, such as jogging in pairs, can be socially engaging. However, if exercise partners have different fitness levels then the activity can be too strenuous for one and not challenging enough for the other, compromising engagement and health benefits. Our system, Jogging over a Distance, uses heart rate data and spatialized sound to create an equitable, balanced experience between joggers of different fitness levels who are geographically distributed. We extend this prior work by analyzing the experience of 32 joggers to detail how specific design features facilitated, and hindered, an engaging and balanced exertion experience. With this knowledge, we derive four dimensions that describe a design space for balancing exertion experiences: Measurement, Adjustment, Presentation and Control. We also present six design tactics for creating balanced exertion experiences described by these dimensions. By aiding designers in supporting participants of different physical abilities, we hope to increase participation and engagement with physical activity and facilitate the many benefits it brings about.

Throwing is an important physical skill that lays the foundation for the ability to participate in many physical activities and sports experiences. We aim to support the development of physical skills through exertion game design; our focus here is on the design of an exertion based throwing game that aims to help children improve their ability to throw. We discuss the results of some initial play testing, and how these observations informed our game design.

Exertion games require investing physical effort. The fact that such games can support physical health is tempered by our limited understanding of how to design for engaging exertion experiences. This paper introduces the Exertion Framework as a way to think and talk about Exertion Games, both for their formative design and summative analysis. Our Exertion Framework is based on the ways in which we can conceive of the body investing in game-directed exertion, supported by four perspectives on the body (the Responding Body, Moving Body, Sensing Body and Relating Body) and three perspectives on gaming (rules, play and context). The paper illustrates how this framework was derived from prior systems and theory, and presents a case study of how it has been used to inspire novel exertion interactions.

Exertion activities, such as jogging, require users to invest intense physical effort and are associated with physical and social health benefits. Despite the benefits, our understanding of exertion activities is limited, especially when it comes to social experiences. In order to begin understanding how to design for technologically augmented social exertion experiences, we present "Jogging over a Distance", a system in which spatialized audio based on heart rate allowed runners as far apart as Europe and Australia to run together. Our analysis revealed how certain aspects of the design facilitated a social experience, and consequently we describe a framework for designing augmented exertion activities. We make recommendations as to how designers could use this framework to aid the development of future social systems that aim to utilize the benefits of exertion.

Exertion games are an emerging form of interactive games that require players to invest significant physical effort as part of the gameplay, rather than just pressing buttons. These exertion games have potential health benefits by promoting exercise. It is also believed that they can facilitate social play between players and that social play can improve participation in exertion games. However, there is currently a lack of understanding of how to design games to support these effects. In this paper, we present a qualitative case study that illustrates how networked environments support social play in exertion games and how this can help to gain an understanding of existing games and support the design of future games. This work offers a preliminary analytical and descriptive account of the relationship between exertion and social play in such a game and highlights the influence of design with the aim of utilizing the attributed benefits of exertion and social play.

Physical play familiar from sports activities is a favorite pastime across all cultures and has been attributed with many social, mental and physical health benefits. However, the players have to be in the same physical location together in order to experience these benefits. To address this issue, an approach is proposed that combines the advantages of exertion interactions, as known from traditional physical games, with the advantages of networked games, such as allowing distributed players to engage and form social bonds over a distance. "Table Tennis for Three" is a prototypal game that allows three players in three geographically distant locations to play a table tennis-like game together with a real ball, table and bat. A critical reflection on the player experience through video analysis resulted in the identification of salient themes. One theme that was identified was the heightened role of the physical, in contrast to the virtual world in which the players act, which affects the way play unfolds. Considering such themes can inform the design of future exertion games and are hoped to inspire a new way of thinking when creating digital games that utilize interaction styles beyond conventional input devices.

People enjoy jogging with others for social and motivational reasons. However, as reported by forum participants, finding a compatible, local jogging partner who shares the ability to jog at the same pace for the same duration is not always easy. One possible way to overcome this challenge is to expand the range of potential jogging partners by allowing for interaction with remote joggers. We investigated whether a jogging experience supporting conversation between remote partners could be desirable and motivating. We conducted an experiment with 18 volunteers using conventional mobile phones with headsets to support conversations as participants jogged in disjoint, outdoor areas. Results show that a simple audio connection supports participants' need to socialize and allows partners to encourage each other.

Intimacy is a crucial element of domestic life, and many interactive technologies designed for other purposes have been appropriated for use within intimate relationships. However, there is a deficit in current understandings of how technologies are used within intimate relationships, and how to design technologies to support intimate acts. In this paper we report on work that has addressed these deficits. We used cultural probes and contextual interviews and other ethnographically informed techniques to investigate how interactive technologies are used within intimate relationships. From this empirical work we generated a thematic understanding of intimacy and the use of interactional technologies to support intimate acts. We used this understanding to inform the design of intimate technologies. A selection of our design concepts is also presented.

An Exertion Interface is an interface that deliberately requires intense physical effort. Exertion Interfaces have applications in "Sports over a Distance", potentially capitalizing on the power of traditional physical sports in supporting social bonding. We designed, developed, and evaluated an Exertion Interface that allows people who are miles apart to play a physically exhausting ball game together. Players interact through a life-size video-conference screen using a regular soccer ball as an input device. The Exertion Interface users said that they got to know the other player better, had more fun, became better friends, and were happier with the transmitted audio and video quality, in comparison to those who played the same game using a non-exertion keyboard interface. These results suggest that an Exertion Interface, as compared to a traditional interface, offers increased opportunities for connecting people socially, especially when they have never met before.