Publications

Year: Author:

Andrea Bönsch, Sina Radke, Heiko Overath, Laura Marie Aschè, Jonathan Wendt, Tom Vierjahn, Ute Habel, Torsten Wolfgang Kuhlen
Proceedings of the IEEE Virtual Reality Conference, 2018

Personal space (PS), the flexible protective zone maintained around oneself, is a key element of everyday social interactions. It, e.g., affects people's interpersonal distance and is thus largely involved when navigating through social environments. However, the PS is regulated dynamically, its size depends on numerous social and personal characteristics and its violation evokes different levels of discomfort and physiological arousal. Thus, gaining more insight into this phenomenon is important.

We contribute to the PS investigations by presenting the results of a controlled experiment in a CAVE, focusing on German males in the age of 18 to 30 years. The PS preferences of 27 participants have been sampled while they were approached by either a single embodied, computer-controlled virtual agent (VA) or by a group of three VAs. In order to investigate the influence of a VA's emotions, we altered their facial expression between angry and happy. Our results indicate that the emotion as well as the number of VAs approaching influence the PS: larger distances are chosen to angry VAs compared to happy ones; single VAs are allowed closer compared to the group. Thus, our study is a foundation for social and behavioral studies investigating PS preferences.

» Show BibTeX

@InProceedings{Boensch2018c,
author = {Andrea B\"{o}nsch and Sina Radke and Heiko Overath and Laura M. Asch\'{e} and Jonathan Wendt and Tom Vierjahn and Ute Habel and Torsten W. Kuhlen},
title = {{Social VR: How Personal Space is Affected by Virtual Agents’ Emotions}},
booktitle = {Proceedings of IEEE Virtual Reality Conference 2018},
year = {2018}
}






Patric Schmitz, Julian Romeo Hildebrandt, André Calero Valdez, Leif Kobbelt, Martina Ziefle
IEEE Transactions on Visualization and Computer Graphics

In virtual environments, the space that can be explored by real walking is limited by the size of the tracked area. To enable unimpeded walking through large virtual spaces in small real-world surroundings, redirection techniques are used. These unnoticeably manipulate the user’s virtual walking trajectory. It is important to know how strongly such techniques can be applied without the user noticing the manipulation—or getting cybersick. Previously, this was estimated by measuring a detection threshold (DT) in highly-controlled psychophysical studies, which experimentally isolate the effect but do not aim for perceived immersion in the context of VR applications. While these studies suggest that only relatively low degrees of manipulation are tolerable, we claim that, besides establishing detection thresholds, it is important to know when the user’s immersion breaks. We hypothesize that the degree of unnoticed manipulation is significantly different from the detection threshold when the user is immersed in a task. We conducted three studies: a) to devise an experimental paradigm to measure the threshold of limited immersion (TLI), b) to measure the TLI for slowly decreasing and increasing rotation gains, and c) to establish a baseline of cybersickness for our experimental setup. For rotation gains greater than 1.0, we found that immersion breaks quite late after the gain is detectable. However, for gains lesser than 1.0, some users reported a break of immersion even before established detection thresholds were reached. Apparently, the developed metric measures an additional quality of user experience. This article contributes to the development of effective spatial compression methods by utilizing the break of immersion as a benchmark for redirection techniques.





Sebastian Freitag, Benjamin Weyers, Torsten Wolfgang Kuhlen
Proceedings of IEEE Virtual Reality Conference 2018

During free exploration of an unknown virtual scene, users often miss important parts, leading to incorrect or incomplete environment knowledge and a potential negative impact on performance in later tasks. This is addressed by wayfinding aids such as compasses, maps, or trails, and automated exploration schemes such as guided tours. However, these approaches either do not actually ensure exploration success or take away control from the user.

Therefore, we present an interactive assistance interface to support exploration that guides users to interesting and unvisited parts of the scene upon request, supplementing their own, free exploration. It is based on an automated analysis of object visibility and viewpoint quality and is therefore applicable to a wide range of scenes without human supervision or manual input. In a user study, we found that the approach improves users' knowledge of the environment, leads to a more complete exploration of the scene, and is also subjectively helpful and easy to use.





Jonathan Wendt, Benjamin Weyers, Andrea Bönsch, Jonas Stienen, Tom Vierjahn, Michael Vorländer, Torsten Wolfgang Kuhlen
IEEE Virtual Humans and Crowds for Immersive Environments (VHCIE), 2018

When interacting and communicating with virtual agents in immersive environments, the agents’ behavior should be believable and authentic. Thereby, one important aspect is a convincing auralizations of their speech. In this work-in progress paper a study design to evaluate the effect of adding directivity to speech sound source on the perceived social presence of a virtual agent is presented. Therefore, we describe the study design and discuss first results of a prestudy as well as consequential improvements of the design.





Daniel Zielasko, Alexander Meißner, Sebastian Freitag, Benjamin Weyers, Torsten Wolfgang Kuhlen
IEEE Virtual Reality Workshop on Everyday Virtual Reality 2018

Various factors influence the degree of cybersickness a user can suffer in an immersive virtual environment, some of which can be controlled without adapting the virtual environment itself. When using HMDs, one example is the size of the field of view. However, the degree to which factors like this can be manipulated without affecting the user negatively in other ways is limited. Another prominent characteristic of cybersickness is that it affects individuals very differently. Therefore, to account for both the possible disruptive nature of alleviating factors and the high interpersonal variance, a promising approach may be to intervene only in cases where users experience discomfort symptoms, and only as much as necessary. Thus, we conducted a first experiment, where the field of view was decreased when people feel uncomfortable, to evaluate the possible positive impact on sickness and negative influence on presence. While we found no significant evidence for any of these possible effects, interesting further results and observations were made.

» Show BibTeX

@InProceedings{zielasko2018,
title={{Dynamic Field of View Reduction Related to Subjective Sickness Measures in an HMD-based Data Analysis Task}},
author={Zielasko, Daniel and Mei{\ss}ner, Alexander and Freitag Sebastian and Weyers, Benjamin and Kuhlen, Torsten W},
booktitle ={Proc. of IEEE Virtual Reality Workshop on Everyday Virtual Reality},
year={2018}
}






Andrea Bönsch
Doctoral Consortium at IEEE Virtual Reality Conference 2018

My research focuses on social locomotion of computer-controlled, human-like, virtual agents in virtual reality applications. Two main areas are covered in the literature: a) user-agent-dynamics in, e.g., pedestrian scenarios and b) pure inter-agent-dynamics. However, joint locomotion of a social group consisting of a user and one to several virtual agents has not been investigated yet. I intend to close this gap by contributing an algorithmic model of an agent’s behavior during social locomotion. In addition, I plan to evaluate the effects of the resulting agent’s locomotion patterns on a user’s perceived degree of immersion, comfort, as well as social presence.

» Show BibTeX

@InProceedings{Boensch2018a,
author = {Andrea B\"{o}nsch},
title = {Locomotion with Virtual Agents in the Realm of Social Virtual Reality},
booktitle = {Doctoral Consortium at IEEE Virtual Reality Conference 2018},
year = {2018}
}






Andrea Bönsch, Sina Radke, Jonathan Wendt, Tom Vierjahn, Ute Habel, Torsten Wolfgang Kuhlen
IEEE Virtual Humans and Crowds for Immersive Environments (VHCIE), 2018

The concept of personal space is a key element of social interactions. As such, it is a recurring subject of investigations in the context of research on proxemics. Using virtual-reality-based experiments, we contribute to this area by evaluating the direct effects of emotional expressions of an approaching virtual agent on an individual’s behavioral and physiological responses. As a pilot study focusing on the emotion expressed solely by facial expressions gave promising results, we now present a study design to gain more insight.

» Show BibTeX

@InProceedings{Boensch2018b,
author = {Andrea B\"{o}nsch and Sina Radke and Jonathan Wendt and Tom Vierjahn and Ute Habel and Torsten W. Kuhlen},
title = {{Towards Understanding the Influence of a Virtual Agent’s Emotional Expression on Personal Space}},
booktitle = {IEEE Virtual Humans and Crowds for Immersive Environments},
year = {2018}
}






Sevinc Eroglu, Sascha Gebhardt, Patric Schmitz, Dominik Rausch, Torsten Wolfgang Kuhlen
Proceedings of IEEE Virtual Reality Conference 2018

Fluid artwork refers to works of art based on the aesthetics of fluid motion, such as smoke photography, ink injection into water, and paper marbling. Inspired by such types of art, we created Fluid Sketching as a novel medium for creating 3D fluid artwork in immersive virtual environments. It allows artists to draw 3D fluid-like sketches and manipulate them via six degrees of freedom input devices. Different sets of brush strokes are available, varying different characteristics of the fluid. Because of fluid's nature, the diffusion of the drawn fluid sketch is animated, and artists have control over altering the fluid properties and stopping the diffusion process whenever they are satisfied with the current result. Furthermore, they can shape the drawn sketch by directly interacting with it, either with their hand or by blowing into the fluid. We rely on particle advection via curl-noise as a fast procedural method for animating the fluid flow.




Julian Romeo Hildebrandt, Patric Schmitz, André Calero Valdez, Leif Kobbelt, Martina Ziefle
Proceedings of HCI International 2018

Cybersickness poses a crucial threat to applications in the domain of Virtual Reality. Yet, its predictors are insufficiently explored when redirection techniques are applied. Those techniques let users explore large virtual spaces by natural walking in a smaller tracked space. This is achieved by unnoticeably manipulating the user’s virtual walking trajectory. Unfortunately, this also makes the application more prone to cause Cybersickness. We conducted a user study with a semi-structured interview to get quantitative and qualitative insights into this domain. Results show that Cybersickness arises, but also eases ten minutes after the exposure. Quantitative results indicate that a tolerance towards Cybersickness might be related to self-efficacy constructs and therefore learnable or trainable, while qualitative results indicate that users’ endurance of Cybersickness is dependent on symptom factors such as intensity and duration, as well as factors of usage context and motivation. The role of Cybersickness in Virtual Reality environments is discussed in terms of the applicability of redirected walking techniques.




Previous Year (2017)
Disclaimer Home Visual Computing institute RWTH Aachen University