Publikationen von Tim Dünte


  • TactileWear: A Comparison of Electrotactile and Vibrotactile Feedback on the Wrist and Ring Finger
    Dennis Stanke, Tim Dünte and Michael Rohs
    Proceedings of the 11th Nordic Conference on Human-Computer Interaction: Shaping Experiences, Shaping Society - NordiCHI '20
    Wearables are getting more and more powerful. Tasks like notifications can be delegated to smartwatches. But the output capabilities of wearables seem to be stuck at displays and vibration. Electrotactile feedback may serve as an energy-efficient alternative to standard vibration feedback. We developed prototypes of wristbands and rings and conducted two studies to compare electrotactile and vibrotactile feedback. The prototypes have either four electrodes for electrotactile feedback or four actuators for vibration feedback. In a first study we analyzed the localization characteristics of the created stimuli. The results suggest more strongly localized sensations for electrotactile feedback, compared to vibrotactile feedback, which was more diffuse. In a second study we created notification patterns for both modalities and evaluated recognition rates, verbal associations, and satisfaction. Although the recognition rates were higher with electrotactile feedback, vibrotactile feedback was judged as more comfortable and less stressful. Overall, the results show that electrotactile feedback can be a viable alternative to vibrotactile feedback for wearables, especially for notification rings.


  • MuscleIO: Muscle-Based Input and Output for Casual Notifications
    Tim Dünte, Justin Schulte, Max Pfeiffer and Michael Rohs
    Proc. ACM Interact. Mob. Wearable Ubiquitous Technol.
    Receiving and reacting to notifications on mobile devices can be cumbersome. We propose MuscleIO, the use of electrical muscle stimulation (EMS) for notification output and electromyography (EMG) for reacting to notifications. Our approach provides a one-handed, eyes-free, and low-effort way of dealing with notifications. We built a prototype that interleaves muscle input and muscle output signals using the same electrodes. EMS and EMG alternate such that the EMG input signal is measured in the gaps of the EMS output signal, so voluntary muscle contraction is measured during muscle stimulation. Notifications are represented as EMS signals and are accepted or refused either by a directional or a time-based EMG response. A lab user study with 12 participants shows that the directional EMG response is superior to the time-based response in terms of reaction time, error rate, and user preference. Furthermore, the directional approach is the fastest and the most intuitive for users compared to a button-based smartwatch interface as a baseline.




  • Cruise Control for Pedestrians: Controlling Walking Direction using Electrical Muscle Stimulation
    Max Pfeiffer, Tim Dünte, Stefan Schneegass, Florian Alt and Michael Rohs
    Proc. of CHI 2015
    Pedestrian navigation systems require users to perceive, interpret, and react to navigation information. This can tax cognition as navigation information competes with information from the real world. We propose actuated navigation, a new kind of pedestrian navigation in which the user does not need to attend to the navigation task at all. An actuation signal is directly sent to the human motor system to influence walking direction. To achieve this goal we stimulate the sartorius muscle using electrical muscle stimulation. The rotation occurs during the swing phase of the leg and can easily be counteracted. The user therefore stays in control. We discuss the properties of actuated navigation and present a lab study on identifying basic parameters of the technique as well as an outdoor study in a park. The results show that our approach changes a user's walking direction by about 16 degree/m on average and that the system can successfully steer users in a park with crowded areas, distractions, obstacles, and uneven ground.