Ultrasound haptics is a contactless haptic technology that enables novel mid-air interactions with rich multisensory feedback. This paper surveys recent advances in ultrasound haptic technology. We discuss the fundamentals of this haptic technology, how a variety of perceptible sensations are rendered, and how it is currently being used to enable novel interaction techniques. We summarize its strengths, weaknesses, and potential applications across various domains. We conclude with our perspective on key directions for this promising haptic technology.

This paper contains a succinct survey on the recent major advances in contactless ultrasonic tactile feedback. It is a haptic technology which enables easy mid-air interactions with rich multisensory feedback and creates effects which are otherwise impossible. It can become a disruptive technology for multimedia interfaces, applications, and mobile computing. We summarize and discuss the advantages, problems and applications of the technology. This survey provides an introduction to the topic for anyone interested in applying or researching it.

The current food production system is unsustainable, necessitating a shift towards plant-based diets. Nutritious options fulfill basic needs but may not satisfy hedonic ones. Our novel approach is to promote healthier eating habits without compromising on the pleasantness of eating by using extended reality technologies and multimodal interaction. We present a multisensory augmentation system integrating augmentations in olfaction, touch, and vision. We studied the experience of eating plant-based balls and meatballs. In an experiment with 40 participants, haptic and visual augmentations were found to have significant effects: augmented meatballs and plant-based balls were perceived as bigger and heavier compared to non-augmented versions. However, olfactory augmentation did not produce a similar effect: participants did not notice a stronger aroma with augmented balls compared to non-augmented balls, and the augmented plant-based version had a less appealing scent than its non-augmented counterpart. Moreover, the findings of the study indicate that our multisensory augmentation system had no significant effect on taste perception.

Ultrasonic tactile stimulation can give the user contactless tactile feedback in a variety of human-computer interfaces. Parameters, such as duration, rhythm, and intensity, can be used to encode information into tactile sensation. The present aim was to investigate the differentiation of six ultrasonic tactile stimulations that were varied by form (i.e., square and circle) and timing (i.e., movement speed and duration, and the number of repetitions). Following a stimulus familiarization task participants (N = 16) were to identify the stimuli presented in the same order as in the familiarization phase. Overall, the results showed that it was significantly easier to identify stimuli that were rendered at a slower pace (i.e., longer duration) regardless of the number of repetitions. Thus, for ultrasonic haptics, rendering time was one important factor for easy identification.

Projected walk-through fogscreens have been created, but there is little research on the evaluation of the interaction performance with fogscreens. The present study investigated mid-air hand gestures for interaction with a large fogscreen. Participants (N = 20) selected objects from a fogscreen using tapping and dwell-based gestural techniques, with and without vibrotactile/haptic feedback. In terms of Fitts’ law, the throughput was about 1.4 bps to 2.6 bps, suggesting that gestural interaction with a large fogscreen is a suitable and effective input method. Our results also suggest that tapping without haptic feedback has good performance and potential for interaction with a fogscreen, and that tactile feedback is not necessary for effective mid-air interaction. These findings have implications for the design of gestural interfaces suitable for interaction with fogscreens.