Publications
Below is a searchable list of publications by the projects of the Priority Program.
1.
Sabnis, Nihar; Zenner, André; Løvaas, Erik Peralta; Weiss, Marco; Bianchi, Andrea; Strohmeier, Paul
Connected Material Experiences using Bimanual Vibrotactile Crosstalk in Virtual Reality Proceedings Article
In: Proceedings of the 2026 CHI Conference on Human Factors in Computing Systems, Association for Computing Machinery, New York, NY, USA, 2026, ISBN: 9798400722783.
Abstract | Links | BibTeX | Tags: bimanual vibrotactile feedback, Consumer VR, material perception, motion-coupled vibrations, virtual reality
@inproceedings{10.1145/3772318.3790767,
title = {Connected Material Experiences using Bimanual Vibrotactile Crosstalk in Virtual Reality},
author = {Nihar Sabnis and André Zenner and Erik Peralta Løvaas and Marco Weiss and Andrea Bianchi and Paul Strohmeier},
url = {https://doi.org/10.1145/3772318.3790767},
doi = {10.1145/3772318.3790767},
isbn = {9798400722783},
year = {2026},
date = {2026-01-01},
booktitle = {Proceedings of the 2026 CHI Conference on Human Factors in Computing Systems},
publisher = {Association for Computing Machinery},
address = {New York, NY, USA},
series = {CHI '26},
abstract = {Perceiving material properties such as elasticity, flexibility, and torsion is inherently bimanual, as we rely on the relative motion of our hands to form a unified sense of materiality. Yet, most vibrotactile material rendering approaches are limited to a single hand or finger. While prior work has explored bimanual haptic interfaces, most depend on specialized hardware for specific interactions. In this paper, we demonstrate design strategies to support bimanual material exploration through motion-coupled vibrotactile feedback. Our technique introduces variable crosstalk between the controllers’ vibration to evoke connectedness, making two unconnected devices feel as though they manipulate a single object. The technique generalizes motion-coupled feedback approaches beyond previous single-point explorations. Through two user studies, we show that this approach (1) significantly enhances perceived connectedness and (2) conveys distinct material qualities such as elasticity and torsion. Finally, we present Dvihastundefinedya, an authoring tool for designing connected bimanual experiences in virtual reality.},
keywords = {bimanual vibrotactile feedback, Consumer VR, material perception, motion-coupled vibrations, virtual reality},
pubstate = {published},
tppubtype = {inproceedings}
}
Perceiving material properties such as elasticity, flexibility, and torsion is inherently bimanual, as we rely on the relative motion of our hands to form a unified sense of materiality. Yet, most vibrotactile material rendering approaches are limited to a single hand or finger. While prior work has explored bimanual haptic interfaces, most depend on specialized hardware for specific interactions. In this paper, we demonstrate design strategies to support bimanual material exploration through motion-coupled vibrotactile feedback. Our technique introduces variable crosstalk between the controllers’ vibration to evoke connectedness, making two unconnected devices feel as though they manipulate a single object. The technique generalizes motion-coupled feedback approaches beyond previous single-point explorations. Through two user studies, we show that this approach (1) significantly enhances perceived connectedness and (2) conveys distinct material qualities such as elasticity and torsion. Finally, we present Dvihastundefinedya, an authoring tool for designing connected bimanual experiences in virtual reality.
2.
Riemer, Martin; Valletta, Elisa; Halbhuber, David; Bogon, Johanna
Anticipating Physical Processes in VR: Environment Type and Scale Alter Temporal Expectations Proceedings Article
In: Proceedings of the 2026 CHI Conference on Human Factors in Computing Systems, Association for Computing Machinery, New York, NY, USA, 2026, ISBN: 9798400722783.
Abstract | Links | BibTeX | Tags: gravity, mental imagery, physical processes, space-time interaction, spatial scale, time perception, virtual reality
@inproceedings{10.1145/3772318.3791767,
title = {Anticipating Physical Processes in VR: Environment Type and Scale Alter Temporal Expectations},
author = {Martin Riemer and Elisa Valletta and David Halbhuber and Johanna Bogon},
url = {https://doi.org/10.1145/3772318.3791767},
doi = {10.1145/3772318.3791767},
isbn = {9798400722783},
year = {2026},
date = {2026-01-01},
booktitle = {Proceedings of the 2026 CHI Conference on Human Factors in Computing Systems},
publisher = {Association for Computing Machinery},
address = {New York, NY, USA},
series = {CHI '26},
abstract = {Accurate temporal expectations support interaction in virtual reality (VR), yet it remains unclear whether the internal models that guide such expectations in the real world transfer unchanged to immersive VR. We report two experiments examining expected durations of gravity-driven motion across real and virtual environments. In Experiment 1, participants imagined a ball rolling down ramps in a physical lab, a 1:1 VR replica, and an up-scaled VR room and produced the time the imagined process would take. Results revealed systematic distortions: durations were underestimated in VR relative to the physical lab, and larger virtual spaces elicited longer durations. Experiment 2 assessed whether participants incorporated gravity laws into their simulations. Although gravitational acceleration was consistently underestimated, it was incorporated in both real and virtual environments. Our findings show that VR and its spatial scale bias temporal expectations, with implications for the design of temporally coherent and physically plausible VR experiences.},
keywords = {gravity, mental imagery, physical processes, space-time interaction, spatial scale, time perception, virtual reality},
pubstate = {published},
tppubtype = {inproceedings}
}
Accurate temporal expectations support interaction in virtual reality (VR), yet it remains unclear whether the internal models that guide such expectations in the real world transfer unchanged to immersive VR. We report two experiments examining expected durations of gravity-driven motion across real and virtual environments. In Experiment 1, participants imagined a ball rolling down ramps in a physical lab, a 1:1 VR replica, and an up-scaled VR room and produced the time the imagined process would take. Results revealed systematic distortions: durations were underestimated in VR relative to the physical lab, and larger virtual spaces elicited longer durations. Experiment 2 assessed whether participants incorporated gravity laws into their simulations. Although gravitational acceleration was consistently underestimated, it was incorporated in both real and virtual environments. Our findings show that VR and its spatial scale bias temporal expectations, with implications for the design of temporally coherent and physically plausible VR experiences.
3.
Kalus, Alexander; Wolf, Katrin; Yildiran, Sümeyye R.; Kocur, Martin
Exploring the Time Course of the Proteus Effect: Effects of Avatar Age and Embodiment Time on Walking in Virtual Reality Proceedings Article
In: Proceedings of the Extended Abstracts of the 2026 CHI Conference on Human Factors in Computing Systems, Association for Computing Machinery, New York, NY, USA, 2026, ISBN: 9798400722813.
Abstract | Links | BibTeX | Tags: Age, Avatar, Embodiment, Proteus Effect, virtual reality
@inproceedings{10.1145/3772363.3799291,
title = {Exploring the Time Course of the Proteus Effect: Effects of Avatar Age and Embodiment Time on Walking in Virtual Reality},
author = {Alexander Kalus and Katrin Wolf and Sümeyye R. Yildiran and Martin Kocur},
url = {https://doi.org/10.1145/3772363.3799291},
doi = {10.1145/3772363.3799291},
isbn = {9798400722813},
year = {2026},
date = {2026-01-01},
booktitle = {Proceedings of the Extended Abstracts of the 2026 CHI Conference on Human Factors in Computing Systems},
publisher = {Association for Computing Machinery},
address = {New York, NY, USA},
series = {CHI EA '26},
abstract = {Avatar appearance can influence users’ behaviour within Virtual Reality (VR), a phenomenon known as the Proteus effect. Prior work suggests that walking behavior after VR exposure is affected by the previously embodied avatar’s apparent age. However, little is known about how such effects unfold during ongoing avatar embodiment in VR. We conducted a study where 32 full-body tracked participants embodied young- and old-looking avatars and repeatedly completed a walking route in VR. Results show that participants walked significantly slower when embodying old-looking avatars. Presence and body ownership increased over time. Interestingly, embodiment duration did not significantly affect the magnitude of the Proteus effect on walking speed, with descriptive differences remaining largely stable. These results suggest that the behavioral impact of avatar age persists without substantial change over a 15 to 20-minute VR session. Our findings contribute to a deeper understanding of avatar age as a design parameter in VR.},
keywords = {Age, Avatar, Embodiment, Proteus Effect, virtual reality},
pubstate = {published},
tppubtype = {inproceedings}
}
Avatar appearance can influence users’ behaviour within Virtual Reality (VR), a phenomenon known as the Proteus effect. Prior work suggests that walking behavior after VR exposure is affected by the previously embodied avatar’s apparent age. However, little is known about how such effects unfold during ongoing avatar embodiment in VR. We conducted a study where 32 full-body tracked participants embodied young- and old-looking avatars and repeatedly completed a walking route in VR. Results show that participants walked significantly slower when embodying old-looking avatars. Presence and body ownership increased over time. Interestingly, embodiment duration did not significantly affect the magnitude of the Proteus effect on walking speed, with descriptive differences remaining largely stable. These results suggest that the behavioral impact of avatar age persists without substantial change over a 15 to 20-minute VR session. Our findings contribute to a deeper understanding of avatar age as a design parameter in VR.
4.
Keppel, Jonas; Prochazka, Marvin; Lewin, Stefan; Stroehnisch, Markus; Strauss, Marvin; Zenner, André; Degraen, Donald; Matviienko, Andrii; Schneegass, Stefan
Determining Perception Thresholds for Real and Virtual Inclinations While Cycling in Virtual Reality Proceedings Article
In: Proceedings of the 2026 CHI Conference on Human Factors in Computing Systems, Association for Computing Machinery, New York, NY, USA, 2026, ISBN: 9798400722783.
Abstract | Links | BibTeX | Tags: Biking, Exergames, Inclination, Indoor Cycling, Perception, Sports, Thresholds, virtual reality
@inproceedings{10.1145/3772318.3791538,
title = {Determining Perception Thresholds for Real and Virtual Inclinations While Cycling in Virtual Reality},
author = {Jonas Keppel and Marvin Prochazka and Stefan Lewin and Markus Stroehnisch and Marvin Strauss and André Zenner and Donald Degraen and Andrii Matviienko and Stefan Schneegass},
url = {https://doi.org/10.1145/3772318.3791538},
doi = {10.1145/3772318.3791538},
isbn = {9798400722783},
year = {2026},
date = {2026-01-01},
booktitle = {Proceedings of the 2026 CHI Conference on Human Factors in Computing Systems},
publisher = {Association for Computing Machinery},
address = {New York, NY, USA},
series = {CHI '26},
abstract = {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},
keywords = {Biking, Exergames, Inclination, Indoor Cycling, Perception, Sports, Thresholds, virtual reality},
pubstate = {published},
tppubtype = {inproceedings}
}
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
5.
Weiss, Yannick; Villa, Steeven; Grootjen, Jesse W; Hoppe, Matthias; Kale, Yasin; Müller, Florian
Exploring Redirection and Shifting Techniques to Mask Hand Movements from Shoulder-Surfing Attacks during PIN Authentication in Virtual Reality Journal Article
In: Proc. ACM Hum.-Comput. Interact., vol. 8, no. MHCI, 2024.
Abstract | Links | BibTeX | Tags: hand redirection, shoulder-surfing, virtual reality
@article{10.1145/3676502,
title = {Exploring Redirection and Shifting Techniques to Mask Hand Movements from Shoulder-Surfing Attacks during PIN Authentication in Virtual Reality},
author = {Yannick Weiss and Steeven Villa and Jesse W Grootjen and Matthias Hoppe and Yasin Kale and Florian Müller},
url = {https://doi.org/10.1145/3676502},
doi = {10.1145/3676502},
year = {2024},
date = {2024-09-01},
urldate = {2024-09-01},
journal = {Proc. ACM Hum.-Comput. Interact.},
volume = {8},
number = {MHCI},
publisher = {Association for Computing Machinery},
address = {New York, NY, USA},
abstract = {The proliferation of mobile Virtual Reality (VR) headsets shifts our interaction with virtual worlds beyond our living rooms into shared spaces. Consequently, we are entrusting more and more personal data to these devices, calling for strong security measures and authentication. However, the standard authentication method of such devices - entering PINs via virtual keyboards - is vulnerable to shoulder-surfing, as movements to enter keys can be monitored by an unnoticed observer. To address this, we evaluated masking techniques to obscure VR users' input during PIN authentication by diverting their hand movements. Through two experimental studies, we demonstrate that these methods increase users' security against shoulder-surfing attacks from observers without excessively impacting their experience and performance. With these discoveries, we aim to enhance the security of future VR authentication without disrupting the virtual experience or necessitating additional hardware or training of users.},
keywords = {hand redirection, shoulder-surfing, virtual reality},
pubstate = {published},
tppubtype = {article}
}
The proliferation of mobile Virtual Reality (VR) headsets shifts our interaction with virtual worlds beyond our living rooms into shared spaces. Consequently, we are entrusting more and more personal data to these devices, calling for strong security measures and authentication. However, the standard authentication method of such devices – entering PINs via virtual keyboards – is vulnerable to shoulder-surfing, as movements to enter keys can be monitored by an unnoticed observer. To address this, we evaluated masking techniques to obscure VR users’ input during PIN authentication by diverting their hand movements. Through two experimental studies, we demonstrate that these methods increase users’ security against shoulder-surfing attacks from observers without excessively impacting their experience and performance. With these discoveries, we aim to enhance the security of future VR authentication without disrupting the virtual experience or necessitating additional hardware or training of users.
6.
Zenner, André; Krüger, Antonio
Shifting & Warping: A Case for the Combined Use of Dynamic Passive Haptics and Haptic Retargeting in VR Proceedings Article
In: Adjunct Proceedings of the 33rd Annual ACM Symposium on User Interface Software and Technology, pp. 1–3, Association for Computing Machinery, Virtual Event, USA, 2020, ISBN: 9781450375153.
Abstract | Links | BibTeX | Tags: dynamic passive haptic feedback, hand redirection, haptic retargeting, virtual reality
@inproceedings{10.1145/3379350.3416166,
title = {Shifting & Warping: A Case for the Combined Use of Dynamic Passive Haptics and Haptic Retargeting in VR},
author = {André Zenner and Antonio Krüger},
url = {https://doi.org/10.1145/3379350.3416166},
doi = {10.1145/3379350.3416166},
isbn = {9781450375153},
year = {2020},
date = {2020-01-01},
booktitle = {Adjunct Proceedings of the 33rd Annual ACM Symposium on User Interface Software and Technology},
pages = {1–3},
publisher = {Association for Computing Machinery},
address = {Virtual Event, USA},
series = {UIST '20 Adjunct},
abstract = {Passive haptic feedback for virtual reality can provide immersive sensations but suffers from scalability issues. To tackle these, two independent concepts have been proposed previously: Dynamic Passive Haptic Feedback (DPHF), leveraging actuated props that change their physical state, and Haptic Retargeting, redirecting the user's hand during interaction. While past research on both techniques reported promising results, up to now, these concepts remained isolated. This paper advocates the combined use of DPHF and Haptic Retargeting. We introduce two thought experiments showcasing that the combination of both techniques in an example scenario is beneficial to solve two central challenges of prop-based VR haptics: haptic similarity and co-location of proxies and virtual objects.},
keywords = {dynamic passive haptic feedback, hand redirection, haptic retargeting, virtual reality},
pubstate = {published},
tppubtype = {inproceedings}
}
Passive haptic feedback for virtual reality can provide immersive sensations but suffers from scalability issues. To tackle these, two independent concepts have been proposed previously: Dynamic Passive Haptic Feedback (DPHF), leveraging actuated props that change their physical state, and Haptic Retargeting, redirecting the user’s hand during interaction. While past research on both techniques reported promising results, up to now, these concepts remained isolated. This paper advocates the combined use of DPHF and Haptic Retargeting. We introduce two thought experiments showcasing that the combination of both techniques in an example scenario is beneficial to solve two central challenges of prop-based VR haptics: haptic similarity and co-location of proxies and virtual objects.