International audience

In virtual reality (VR) experiences, mismatches between reality and virtuality are usually undesirable, as they can disrupt immersion and induce cybersickness. However, when carefully controlled, they may expand the design space of VR. This research investigates perceptual detection thresholds for mismatches between real and virtual inclinations during cycling in VR. Using a custom simulation, N = 30 participants cycled through a virtual city while physical and visual inclinations were independently manipulated. Real inclinations were implemented with a tilting indoor bike, providing vestibular and proprioceptive feedback, while virtual inclinations within the simulated environment were presented visually. A multiple staircase procedure derived estimates for perceptual thresholds that approximate which mismatches in visual and physical inclination were still perceived as congruent. These thresholds reveal a window of perceived congruence before mismatches become noticeable to users. These findings advance understanding of sensory integration in VR cycling and inform applications in immersive training, exergames, and rehabilitation systems.

The way users hold a smartphone depends on the interaction task, yet little is known about the fingers’ engagement with the device’s surfaces beyond the touchscreen. Such an understanding not only opens up opportunities for novel on- and off-screen interactions, but also the device’s possible physical affordances. We present a study (N=23) that examines the hands’ physical engagement with the smartphone beyond the touchscreen across nine mobile interactions. Grasps were annotated from photographs, and contact regions were captured using residual heat traces from grasping the device. Our findings show that fingers and palms adopt a variety of support roles and postures when engaging with the smartphone’s back and side edges. The hand-contact maps reveal distinct patterns, differing in contact frequency and placement. This work contributes an empirical characterisation of hands’ back and edge engagement, highlighting design opportunities for future smartphone usage extending beyond the touchscreen.

Virtual Reality (VR) depends on haptic feedback to create immersive experiences. Traditional passive proxies align physical props with their virtual counterparts but remain limited in scalability and expressiveness, or require bulky actuators to support reconfiguration. We introduce User-reconfigured Haptics, an approach that utilizes implicit user actions to reconfigure haptic interfaces to extend the gamut of VR haptic experiences. Modular 3D-printed cells are assembled into dynamic interfaces that express diverse haptic properties such as softness and weight. By masking physical reconfigurations with visual (re)mapping, user actions unnoticeably change haptic properties, resulting in user-driven, dynamic haptic experiences. User studies show that our design can provide distinguishable haptic experiences and is perceived as realistic and enjoyable in a VR task. We further showcase four applications: a fishing rod that changes weight and flexibility, a dynamic desktop of pressable buttons, a glove with adjustable squeezing, and a crossbow with variable pulling resistance.

| openaire: EC/HE/101070533/EU//EMIL

Augmented Reality (AR) is promising in providing individual learning support for students.However, it is currently unknown which display technology is appropriate to use in classroom settings.In this work, we investigate different AR displays and their usability

CHI ’25, April 26–May 01, 2025, Yokohama, Japan

In Virtual Reality (VR), rendering realistic forces is crucial for immersion, but traditional vibrotactile feedback fails to convey force sensations effectively. Studies of asymmetric vibrations that elicit pseudo forces show promise but are inherently tied to unwanted vibrations, reducing realism. Leveraging sensory attenuation to reduce the perceived intensity of self-generated vibrations during user movement, we present a novel algorithm that couples asymmetric vibrations with user motion, which mimics self-generated sensations. Our psychophysics study with 12 participants shows that motion-coupled asymmetric vibration attenuates the experience of vibration (equivalent to a ∼30% reduction in vibration-amplitude) while preserving the experience of force, compared to continuous asymmetric vibrations (state-of-the-art). We demonstrate the effectiveness of our approach in VR through three scenarios: shooting arrows, lifting weights, and simulating haptic magnets. Results revealed that participants preferred forces elicited by motion-coupled asymmetric vibration for tasks like shooting arrows and lifting weights. This research highlights the potential of motion-coupled asymmetric vibrations, offers new insights into sensory attenuation, and advances force rendering in VR.

We present a sensory substitution-based method for representing locations of remote objects in 3D space via haptics. By imitating auditory localization processes, we enable vibrotactile localization abilities similar to those of some spiders, elephants, and other species. We evaluated this concept in virtual reality by modulating the vibration amplitude of two controllers depending on relative locations to a target. We developed two implementations applying this method using either ear or hand locations. A proof-of-concept study assessed localization performance and user experience, achieving under 30° differentiation between horizontal targets with no prior training. This unique approach enables localization by using only two actuators, requires low computational power, and could potentially assist users in gaining spatial awareness in challenging environments. We compare the implementations and discuss the use of hands as ears in motion, a novel technique not previously explored in the sensory substitution literature.

Designing vibrotactile experiences collaboratively requires communicating using multiple senses. This is challenging in remote scenarios as designers need to effectively express and communicate their intention while iteratively building and refining experiences, ideally in real-time. We formulate design considerations for collaborative haptic design tools, and propose CollabJam, a collaborative prototyping suite enabling remote synchronous design of vibrotactile experiences for on-body applications. We first outline Collab-Jam's features and present a technical evaluation. Second, we use CollabJam to understand communication and design patterns used during haptic experience design. We performed an in-depth design evaluation spanning four sessions in which four pairs of participants designed and reviewed vibrotactile experiences remotely. A qualitative content analysis revealed how multi-sensory communication is essential to convey ideas, how stimulating the tactile sense can interfere with personal boundaries, and how freely placing actuators on the skin can provide both benefits and challenges.

Gait is a distinctive behavioral trait, yet its vulnerability against imitation remains underexplored in immersive environments. We present a study investigating how real-time visual feedback in virtual reality (VR) influences a person’s ability to mimic another’s gait. Through two experiments, we first identify the most usable feedback design (N = 8), then evaluate its impact on imitation performance compared to a baseline without feedback (N = 18). We analyze positional and rotational similarity between participants and target avatars, examining the influence of avatar–user gender matching and repeated practice. Our findings reveal that visual feedback significantly improves rotational alignment and that practice leads to measurable improvements in mimicry accuracy. We discuss implications for avatar embodiment, personalization in VR applications, and potential considerations for behavioral biometric systems. We also contribute a publicly available dataset of gait mimicry in VR, supporting further research on motion learning and imitation.

Spatial Augmented Reality (SAR) can enhance learning experiences through interactive, real-time digital information overlays. Using SAR, content can be projected directly onto physical paper to provide students with in situ task feedback. Our work explores how students perceive different types of SAR feedback. We first identified feedback methods and dimensions from a literature review. We then conducted an expert focus group (N = 5) of professionals who had backgrounds in education and teaching experience. With the focus group, we aimed to expand on the literature review results to identify feedback modalities and dimensions commonly used in classrooms today. Next, we performed a field study (N = 16) with high school students in which we compared the perception of different feedback modalities (text, image, video) and familiarity (neutral, unfamiliar, familiar) in a classroom setting. Our results revealed that perceived user distraction and novelty are significantly affected by feedback modality through a large effect, with videos being perceived as more distracting and more novel. Familiar, trusted individuals best deliver positive feedback, whereas negative feedback from people should be avoided. We discuss the usage of feedback modalities in various contexts, providing a foundation for future use of SAR feedback in education.

Meditation can enhance mental well-being, but practicing meditation regularly can be challenging. In this work, we present SoulGarden - a gamified, web-based meditation app that draws on the narrative of personal growth, a guiding avatar and several progress-related mechanics to increase users' enjoyment in meditation and thereby enhance their meditation habits, mindfulness, and mental well-being. We conducted a within-subjects field study spanning four weeks (N=30) in which we evaluated the effectiveness of SoulGarden by comparing it to a non-gamified version and baseline measures. Our results show users meditated a lot using SoulGarden and the addition of gamification increased user enjoyment, frequency of meditation, and mindfulness. Thus, we contribute evidence for the potential of gamification to increase engagement and enhance mindfulness in meditation practices, ultimately paving the way to more effective mental health interventions.

In gamification users show increased motivation and engagement towards tasks. So far, this effect has mostly been empirically tested based on the visual depiction of game elements, while research on the use and addition of auditory aspects is sparse. In this work we investigate the effect of different modalities of game elements (auditory, visual, audiovisual) on user experience, perception and performance in a gamified image-tagging task. We approached this via an online validation survey to find suitable sound effects (N=50), a main quantitative study (N=109) and a qualitative semi-structured interview (N=9). Our results show that while visual gamification increases performance, auditory and audiovisual gamification had no effect. However, they were shown to have an influence on the user's flow state. Our qualitative follow-up study shed light on underlying reasons and revealed each modality has its own drawbacks and advantages and that combining both visual and auditory aspects was preferred by participants.

We present TactJam, an end-to-end suite for creating and sharing low fidelity prototypes of on-body vibrotactile feedback. With TactJam, designers can create, record and share vibrotactile patterns online. This opens up new ways of collaboratively designing vibrotactile patterns both in collocated as well as in remote settings. We evaluate TactJam in a two-part distributed online workshop, exploring the design of on-body tactons. Participants were able to successfully use TactJam to learn about tacton design. We present an overview of mappings between tactons and their associated concepts before comparing the results of tactons created using solely a GUI and tactons created through experimenting with placements directly on the body. Conducting both parts of the workshop separately highlighted the importance of designing directly with bodies: less implicit assumptions were made, and designs were guided by personal experience. We reflect on these results and close on deliberations for the future development of TactJam.

Modern, globalized lifestyles make physical separation of family members an inevitable part of life. Due to changes in routines and social roles, remaining connected to distant loved ones is challenging and adversely affects psychological well-being. To support relatedness, we created FamilyFlower, an artificial flower aimed at fostering a connection between remote households by bringing awareness of everyday activities and offering basic expressivity. In its environment, each device detects human presence, movement, sound, and touch. In the remote household, the paired prototype responds by respectively opening the flower bud, actuating the stem, altering the seeds’ color, and dispensing a fragrance. In a 2-week study of deployment between 2 family members, we collected initial impressions of our prototype, and identified key aspects our system could support in future research. From our results, we see that FamilyFlower supports an awareness of ongoing activities in a distant household and built a feeling of connectedness.

Effective haptic feedback in virtual reality (VR) is an essential element for creating convincing immersive experiences. To design such feedback, state-of-the-art VR setups provide APIs for programmatically generating controller vibration patterns. While tools for designing vibrotactile feedback keep evolving, they often require expert knowledge and rarely support direct manipulation methods for mapping feedback to user interactions within the VR environment. To address these challenges, we contribute a novel concept called Weirding Haptics, that supports fast-prototyping by leveraging the user’s voice to design such feedback while manipulating virtual objects in-situ. Through a pilot study (N = 9) focusing on how tactile experiences are vocalized during object manipulation, we identify spatio-temporal mappings and supporting features needed to produce intended vocalizations. To study our concept, we built a VR design tool informed by the results of the pilot study. This tool enables users to design tactile experiences using their voice while manipulating objects, provides a set of modifiers for fine-tuning the created experiences in VR, and allows to rapidly compare various experiences by feeling them. Results from a validation study (N = 8) show that novice hapticians can vocalize experiences and refine their designs with the fine-tuning modifiers to match their intentions. We conclude our work by discussing uncovered design implications for direct manipulation and vocalization of vibrotactile feedback in immersive virtual environments.

Tactile feedback of an object’s surface enables us to discern its material properties and affordances. This understanding is used in digital fabrication processes by creating objects with high-resolution surface variations to influence a user’s tactile perception. As the design of such surface haptics commonly relies on knowledge from real-life experiences, it is unclear how to adapt this information for digital design methods. In this work, we investigate replicating the haptics of real materials. Using an existing process for capturing an object’s microgeometry, we digitize and reproduce the stable surface information of a set of 15 fabric samples. In a psychophysical experiment, we evaluate the tactile qualities of our set of original samples and their replicas. From our results, we see that direct reproduction of surface variations is able to influence different psychophysical dimensions of the tactile perception of surface textures. While the fabrication process did not preserve all properties, our approach underlines that replication of surface microgeometries benefits fabrication methods in terms of haptic perception by covering a large range of tactile variations. Moreover, by changing the surface structure of a single fabricated material, its material perception can be influenced. We conclude by proposing strategies for capturing and reproducing digitized textures to better resemble the perceived haptics of the originals.

Experiencing materials in virtual reality (VR) is enhanced by combining visual and haptic feedback. While VR easily allows changes to visual appearances, modifying haptic impressions remains challenging. Existing passive haptic techniques require access to a large set of tangible proxies. To reduce the number of physical representations, we look towards fabrication to create more versatile counterparts. In a user study, 3D-printed hairs with length varying in steps of 2.5 mm were used to influence the feeling of roughness and hardness. By overlaying fabricated hair with visual textures, the resolution of the user's haptic perception increased. As changing haptic sensations are able to elicit perceptual switches, our approach can extend a limited set of textures to a much broader set of material impressions. Our results give insights into the effectiveness of 3D-printed hair for enhancing texture perception in VR.

The widespread popularity of Pokémon GO presents the first opportunity to observe the geographic effects of location-based gaming at scale. This paper reports the results of a mixed methods study of the geography of Pokémon GO that includes a five-country field survey of 375 Pokémon GO players and a large scale geostatistical analysis of game elements. Focusing on the key geographic themes of places and movement, we find that the design of Pokémon GO reinforces existing geographically-linked biases (e.g. the game advantages urban areas and neighborhoods with smaller minority populations), that Pokémon GO may have instigated a relatively rare large-scale shift in global human mobility patterns, and that Pokémon GO has geographically-linked safety risks, but not those typically emphasized by the media. Our results point to geographic design implications for future systems in this space such as a means through which the geographic biases present in Pokémon GO may be counteracted.

In this paper, we set out to find what encompasses an appropriate visual language for information presented on near-eye out-of-focus displays. These displays are positioned in a user's peripheral view, very near to the user's eyes, for example on the inside of the temples of a pair of glasses. We explored the usable display area, the role of spatial and retinal variables, and the influence of motion and interaction for such a language. Our findings show that a usable visual language can be accomplished by limiting the possible shapes and by making clever use of orientation and meaningful motion. We found that especially motion is very important to improve perception and comprehension of what is being displayed on near-eye out-of-focus displays, and that perception is further improved if direct interaction with the content is allowed.

Navigation systems allow drivers to find the shortest or fastest path between two or multiple locations mostly using time or distance as input parameters. Various researchers extended traditional route planning approaches by taking into account the user's preferences, such as enjoying a coastal view or alpine landscapes during a drive. Current approaches mainly rely on volunteered geographic information (VGI), such as point of interest (POI) data from OpenStreetMap, or social media data, such as geotagged photos from Flickr, to generate scenic routes. While these approaches use proximity, distribution or other spatial relationships of the data sets, they do not take into account the actual view on specific route segments. In this paper, we propose Autobahn: a system for generating scenic routes using Google Street View images to classify route segments based on their visual characteristics enhancing the driving experience. We show that this vision-based approach can complement other approaches for scenic route planning and introduce a personalized scenic route by aligning the characteristics of the route to the preferences of the user.