Logo des Repositoriums

Auflistung nach Autor:in "Wolf, Katrin"

1 - 10 von 16
  • Workshopbeitrag
    An analysis of the effects of swarm cycling on cyclists’ stress levels
    (Mensch und Computer 2023 - Workshopband, 2023) Schaffer, Stefan; Meng, Linglong; Hemdane, Alaaeddine; Wolf, Katrin; Tsovaltzi, Dimitra; Chehayeb, Lara; Gebhard, Patrick
    Swarm cycling has been proposed in previous researches as a novel concept for urban mobility, by adopting the "safety in number" approach, to enhance the visibility of cyclists in urban traffic and to increase the safety of cyclists. To investigate the effects of swarm cycling on the stress level of bicyclists, we conducted an experiment in an enclosed traffic training field with stressors, such as construction sites, etc. to simulate the stress situations in real traffic. A stress detection system utilizing the Galvanic Skin Response (GSR) sensor and an Android application was developed to monitor participants’ stress responses during cycling. In this research, 21 participants engaged in various cycling scenarios, including cycling alone, cycling within a swarm, and cycling in different positions within the swarm. GSR signal data were collected to quantify the number of stress peaks experienced by each participant during the rides. The data were subjected to statistical analysis to compare stress levels among the different cycling scenarios. The results of the statistical analysis indicate that swarm cycling has a positive impact on individual cyclist stress levels compared to cycling alone. However, there was no statistically significant difference in stress levels observed among different cycling positions within the swarm. This research provides insights into the potential benefits of swarm cycling as an urban mobility solution, emphasizing its positive influence on cyclist stress levels, thus encouraging the adoption of this novel concept to enhance safety and comfort for urban cyclists.
  • Konferenzbeitrag
    ArmTouch: The Forearm as Touchpad for VR Control
    (Mensch und Computer 2019 - Tagungsband, 2019) Reich, Kristin; Jäger, Elisabeth; Do, Xuan Linh; Wolf, Katrin
    Interacting with elements inside a virtual reality (VR) experience is usually done with a controller. However, they tend to be clunky and cumbersome to use. We designed an alternative controller that allows for a rich touch interaction. Our prototype uses the forearm for touch input in VR. The forearm is easy to find through proprioception and also displayed through the HMD. We implemented two versions, one using a touchpad mounted at the forearm and one where the input is realized through touching only the skin of one’s arm. Users can select items of different menu types and through different gestures. A user study showed that both concepts show good usability, but none of the two touch mechanisms was preferred over the other.
  • Zeitschriftenartikel
    Body Language of Avatars in VR Meetings as Communication Status Cue: Recommendations for Interaction Design and Implementation
    (i-com: Vol. 21, No. 1, 2022) Kurzweg, Marco; Wolf, Katrin
    While traditional videoconferencing causes privacy issues, virtual meetings are not yet widely used. Their communication quality still lacks usability and important non-verbal communication cues, such as body language, are underrepresented. We aim at exploring virtual avatars’ body language and how it can be used to indicate meeting attendees’ communication status. By comparing users’ perceptions of avatar behavior, we found that avatar body language across gender can be an indication of communication willingness. We derive resulting body language design recommendations and recommend using attentively behaving avatars as default body language and to indicate being busy through actions of the avatar, such as drinking, typing, or talking on a phone. These actions indicate that users are temporarily busy with another task, but still are attending the meeting. When users are unavailable, their avatars should not be displayed at all and in cases of longer meeting interruptions, the avatar of a user should leave the virtual meeting room.
  • Konferenzbeitrag
    The Effect of Camera Perspectives on Locomotion Accuracy in Virtual Reality
    (Mensch und Computer 2019 - Tagungsband, 2019) Ujkani, Arbresh; Willms, Jan; Turgut, Lezgin; Wolf, Katrin
    This paper investigates the effect of commonly used camera perspectives (First-person perspective, over the shoulder, behind the back and from top to bottom) on locomotion efficiency in virtual reality (VR). To test this research objective in a user study, a virtual test environment was implemented in which a ball can be maneuvered using four different camera perspectives. We analyzed the time taken to complete four different paths and the offset between the path taken and the optimal one (path accuracy) displayed on the ground. The study results show that the "first person perspective" and "behind the back" perspectives allow more precise maneuvering in VR, while no difference in speed was found. We defined guidelines that can help game designers and VR developers to create VR applications with high accuracy needs. Our findings are relevant, especially to decide which perspectives are best for specific applications that require high accuracy, such as remote surgery.
  • Konferenzbeitrag
    The Effect of Presence and Appearance of Guides in Virtual Reality Exhibitions
    (Mensch und Computer 2019 - Tagungsband, 2019) Rzayev, Rufat; Karaman, Gürkan; Wolf, Katrin; Henze, Niels; Schwind, Valentin
    Virtual reality (VR) enables users to experience informal learning activities, such as visiting museum exhibitions or attending tours independent of their physical locations. Consequently, VR offers compelling use cases by making informal learning and education accessible to a broader audience and simultaneously reducing the carbon footprint. For many learning activities, the presence of a human guide is essential for participants' experience. The effect of the presence of a guide and its appearance in VR is, however, unclear. In this paper, we compare a real-world guide with a realistic, an abstract, and an audio-only representation of a virtual guide. Participants followed four multimodal presentations while we investigated the effect on comprehension, presence, co-presence and the perception of the guide. Our results show that even a realistic presentation of a guide results in significantly lower co-presence, humanness, and attractiveness compared to a human guide. Qualitative results and participants' feedback indicate that having no visual representation of the guide helps to focus on the content but can reduce the connection with the guide.
  • Konferenzbeitrag
    Furniture CGI Presentation as 2D Renderings or Virtual Reality?
    (Mensch und Computer 2019 - Tagungsband, 2019) Spleet, Anna-Lena; Kahya, Dennis; Eckhardt, Sören; Niercke, Nils; Wolf, Katrin
    Recent developments in 3D content generation have great potential for immersive object or product representation useful for advertising and promotion. Computer generated Imagery (CGI) production is increasingly replacing the traditional photo shooting process. Virtual Reality (VR) can serve as virtual showroom for the manufacturing industry presenting 3D object content of CGI. We take the business case of furniture sales as example. Here, the established product presentation is realized through 2D images. Using 3D interactive environments would allow to present different operable furniture elements in a simple and clear way. This research intends to explore and compare the influence of two product presentation formats, Computer generated Photo (2D) and VR experience (3D. A user study comparing both presentation modes showed that both presentation formats have their pros and cons, and the purpose of usage is an important factor when deciding for one or another approach. To convey the proportions, feeling of size, relation and dimension as well as the effect of an object in room, a presentation in a 3D environment is recommended. If the focus is more on detail and photorealism, 2D pictures have their advantages.
  • Konferenzbeitrag
    Haptic Illusion Glove: A Glove for Illusionary Touch Feedback when Grasping Virtual Objects
    (Mensch und Computer 2019 - Tagungsband, 2019) Bickmann, Raoul; Tran, Celine; Ruesch, Ninja; Wolf, Katrin
    When touching virtual objects, we lack haptic feedback using commonly and commercially available VR controllers, such as the HTC Vive Controller or Oculus Touch. Haptic Illusion Glove is a wearable device used to create the haptic illusion when grasping objects. When the fingers touch the palm and we see our (in reality empty hand) in virtual reality holding an object, we “feel” the virtual object in our hand. We basically believe the touch of our fingers felt at our palm can be induced by the held object. This concept assumes that vision-based proprioceptive illusion creates the impression of having a grasping hand, even though the thumb is not perfectly abducted. In this paper, we present a user study that indicated cylindrical objects of a certain diameter range are suitable to create haptic grasp feedback for virtual objects. To create a believable illusion, the diameter of the grasped object has to be small enough to allows for one-handed grasping the object. In a user study, we explored the usability of Haptic Illusion Glove when grasping different objects. Our results indicate a high usability of Haptic Illusion Glove when grasping a cup, a hammer, and a water can.
  • Konferenzbeitrag
    HapticCollider: Ungrounded Force Feedback for Rigid Collisions during Virtual Tool Use
    (Mensch und Computer 2023 - Tagungsband, 2023) Olaya-Figueroa, Juan F.; Streicher, Ferdinand; Kurzweg, Marco; Willms, Jan; Wolf, Katrin
    Controllers are not merely the dominant interface to interact in virtual reality (VR); they also are the main resource for haptically perceiving the virtual world. As standard VR controllers fail in generating realistic haptic feedback, we designed HapticCollider, a kinetic controller rendering force feedback, e.g., to simulate a collision when hammering against a virtual object. In our user study, we demonstrated that HapticCollider significantly increases realism in tool usage compared with a standard VR controller. As key factors for tool use realism in VR, we identified force feedback, controller weight, and grip shape in combination with software solutions, namely collision prediction, and control-display ratio to render the force timing, as well as, the tool position according to the user's expectations.
  • Konferenzbeitrag
    Increasing Realism of Displayed Vibrating AR Objects through Edge Blurring
    (Mensch und Computer 2023 - Tagungsband, 2023) Kurzweg, Marco; Letter, Maximilian; Wolf, Katrin
    Many standard AR devices, such as the HoloLens2, have limitations in displaying fast motions, like the ones required to visualize moving or vibrating objects. One reason for this is the low computing power compared to other technologies, resulting in frame rate drops. Further, established visualization enhancement methods, such as anti-aliasing, cannot be applied because of their high computational demands. Therefore, we have looked at possible alternatives on the HoloLens2 for displaying vibrations more realistically as long as these technical limitations exist. We have chosen to examine vibrations as they are widely used for different use cases, like creating feedback, communicating the success of interactions, and generating a better scene understanding. In a user study, three different effects were evaluated against a baseline method, which was the representation of a vibration using a sinus function to calculate the displacement of the object. We found that an effect where the edges of the AR object are blurred (continuously with changing intensity) is perceived as significantly more realistic than other effects and the baseline method.
  • Zeitschriftenartikel
    Mensch und Computer 2019 in Hamburg
    (i-com: Vol. 18, No. 3, 2019) Steinicke, Frank; Wolf, Katrin