Sampling strategy for ultrasonic mid-air haptics

Mid-air tactile stimulation using ultrasonics has been used in a variety of human computer interfaces in the form of prototypes as well as products. When generating these tactile patterns with mid-air tactile ultrasonic displays, the common approach has been to sample the patterns using the hardware update rate capabilities to their full extent. In the current study we show that the hardware update rate can impact perception, but unexpectedly we find that higher update rates do not improve pattern perception. In a first user study, we highlight the effect of update rate on the perceived strength of a pattern, especially for patterns rendered at slow rate of less than 10 Hz. In a second user study, we identify the evolution of the optimal update rate according to variations in pattern size. Our main results show that update rate should be designated as additional parameter for tactile patterns. We also discuss how the relationships we defined in the current study can be implemented into designer tools so that designers remain oblivious to this additional complexity

Haptics: Science, Technology, Applications

This open access book constitutes the proceedings of the 12th International Conference on Human Haptic Sensing and Touch Enabled Computer Applications, EuroHaptics 2020, held in Leiden, The Netherlands, in September 2020. The 60 papers presented in this volume were carefully reviewed and selected from 111 submissions. The were organized in topical sections on haptic science, haptic technology, and haptic applications. This year's focus is on accessibility

OpenMPD: A Low-Level Presentation Engine for Multimodal Particle-Based Displays

Phased arrays of transducers have been quickly evolving in terms of software and hardware with applications in haptics (acoustic vibrations), display (levitation), and audio. Most recently, Multimodal Particle-based Displays (MPDs) have even demonstrated volumetric content that can be seen, heard, and felt simultaneously, without additional instrumentation. However, current software tools only support individual modalities and they do not address the integration and exploitation of the multi-modal potential of MPDs. This is because there is no standardized presentation pipeline tackling the challenges related to presenting such kind of multi-modal content (e.g., multi-modal support, multi-rate synchronization at 10 KHz, visual rendering or synchronization and continuity). This article presents OpenMPD, a low-level presentation engine that deals with these challenges and allows structured exploitation of any type of MPD content (i.e., visual, tactile, audio). We characterize OpenMPD’s performance and illustrate how it can be integrated into higher-level development tools (i.e., Unity game engine). We then illustrate its ability to enable novel presentation capabilities, such as support of multiple MPD contents, dexterous manipulations of fast-moving particles, or novel swept-volume MPD content

HaptiGlow: Helping Users Position their Hands for Better Mid-Air Gestures and Ultrasound Haptic Feedback

We present HaptiGlow, a technique that combines ultrasound haptics with peripheral visual feedback to help users find where to place their hand for improved mid-air interaction. Hand position is important. If a user's hand is poorly placed, input sensors may have difficulty recognising their gestures. Mid-air haptic feedback is also hard to perceive when the hand is in a poor position. Our novel feedback addresses this important usability problem. Our results show the combination of ultrasound haptics and peripheral visuals is effective, with the strengths of each leading to accurate (23mm) and fast (4.6s) guidance in a 3D targeting task. Our technique improves midair interaction by easily helping users find a good hand position

Haptics: Science, Technology, Applications

This open access book constitutes the proceedings of the 12th International Conference on Human Haptic Sensing and Touch Enabled Computer Applications, EuroHaptics 2020, held in Leiden, The Netherlands, in September 2020. The 60 papers presented in this volume were carefully reviewed and selected from 111 submissions. The were organized in topical sections on haptic science, haptic technology, and haptic applications. This year's focus is on accessibility

Exploration of mid-air haptics experience design

Ultrasonic Mid-air Haptics (UMH) is a novel technology that uses the mechanical properties of sound waves to create a pressure point in mid-air. This pressure point, called focal point, can slightly bend the skin and be felt in mid-air without any attachment to the body. This thesis focuses on both studying how to integrate this technology with other senses (i.e. vision and audition) and exploring the range of tactile sensations it can provide. The first two projects presented in this document present the integration of ultrasonic mid-air haptics with audio-visual content. The first project describes the process of creating a unique haptic experience that was part of a six-weeks multisensory exhibition in a museum. The second project moved from the museum to a controlled environment and explored the creation of haptic experiences based on physiologic measurements for six short films. Both studies showed the positive value of adding ultrasonic mid-air haptics to traditional media through higher reported arousal and participants’ high enthusiasm for multisensory content. In the two latter projects of this thesis, it was explored how we could extend the range of possible tactile sensations provided by UMHs. We introduced a new technique called Spatio-Temporal Modulation (STM). It enabled the creation of brand-new tactile experiences, including more salient shapes and wider range of textures. We also provided some guidelines on how to control some of the tactile properties of the sensation, including strength,roughness,or regularity. The findings of those four projects contribute to the growing body of knowledge of UMHs. A summary of the key contributions is provided at the end of the thesis as well as several leads for future works