Humans can distinguish two short simultaneous touches on the forearm, called Two-Point Discrimination (2PD), starting at a distance of approximately 40 mm. However, similar insights are lacking for vibrotactile stimuli, which would be essential for designing ergonomic gesture wristbands. Thus, an oriented 2PD test was performed using vibrotactile actuators on the forearm placed around the wrist (transverse) and along the forearm (longitudinal). The results indicate that the orientation between two actuators cannot be robustly distinguished. Two simultaneous stimuli on the forearm can best be detected at 90 mm distance, with a success rate of up to 96% for transverse placement when the actuators are arranged around the wrist. In this case, the actuators are approximately placed opposite each other, looking at the wrist as a circle. Thus, an actuator arrangement around the wrist is most sufficient to distinguish between a single and two simultaneous vibrotactile stimuli.

We use simple stickers on a wooden board to create ubiquitous touch interaction.Resonant frequencies make the board vibrate, creating tactile feedback when touching the stickers.In an experiment, we used stickers of three sizes to create Resonant Sticker Buttons and varied the delay of the feedback.Both size and feedback delay influenced the perceived weight of the buttons.While higher latencies result in a heavier perceived button, larger button sizes result in lighter perceived buttons and perceived feedback strength, and vice versa.Our findings suggest that touch interfaces with buttons of varying sizes, weights, and vibration strengths can be created on everyday surfaces, such as tables, by simply using stickers and speakers.

With the evolution of hardware and technologies within the last decades, workspaces, ways of living, and consequently, the demands on interactions have changed enormously. However, haptic feedback remains a constant and critical factor in enriching the user experience. Realistic haptic feedback usually demands complex hardware integration, which is not always feasible or desired. These requirements and limitations can be reduced by producing or altering haptic experiences through sensory illusions.

Vibrations are the dominant way to create haptic feedback for interactive systems and are most often induced by vibrotactile actuators. However, virtual content created for augmented reality usually does not support that modality, instead relying mainly on visual and auditive output. Aiming to provide haptic feedback for augmented reality in cases where real vibrations cannot be used, we explore how vibrations can be felt using vision and audio only. In a user study, a virtual 10 x 10 cm white square-shaped cuboid was influenced by animation and/or sound to induce a haptic illusion when being touched. We were able to identify a specific range where the perception of vibration was significantly stronger and more realistic compared to all other values. This was the case if the virtual object’s edges were blurred up to a range of 0.4 cm or 0.6 cm, correspondingly accompanied by sounds, where the spectrum was cut off at a frequency of 256 Hz (for 0.4 cm) or 966 Hz (for 0.6 cm). With that, we aim to enrich augmented reality systems.

While traditional interfaces in human-computer interaction mainly rely on vision and audio, haptics becomes more and more important. Haptics cannot only increase the user experience and make technology more immersive, it can also transmit information that is hard to interpret only through vision and audio, such as the softness of a surface or other material properties. In this workshop, we aim at discussing how we could interact with technology if haptics is strongly supported and which novel research areas could emerge.

During physical games, we love to socially interact with other players through bluffing or giving them hits. This work aims to enrich AR characters by adding a suggestive behavior to them intended to playfully influence game decisions. In a user study, we evaluated such behaviors presented as body postures by animated card characters using an AR trading card game. Our results indicate that AR characters can indeed influence the player’s game decisions through postures that encourage or discourage to play a certain card. Our approach enriches the game design space, can make the game more interesting, and finally adds a social component to the game.