Investigation on Tactile Perception of Ultrasonic Haptics Devices

Haptics have increasingly gained importance in the field of user interface design by addressing tactile sensing in addition to visual and acoustic stimulation. Mid-air haptics allow tactile feedback without contact or wearable hardware and offer advanced control and output mechanisms as well as different sensory modalities for user interfaces (UI) and Virtual/Augmented Reality (VR/AR) applications. Using mid-air haptics virtual objects can offer tactile interaction, thus making contact-free UI interaction more viable. This paper investigates the user perception of ultrasonic haptic signals. By presenting test subjects a broad selection of haptic signals and researching the actually perceived stimuli as well as inquiring the test subjects’ thoughts about their experience, conclusions on the optimal design and application of ultrasonic haptic signals are made. This is done by comparing haptic signals of different shapes and dynamics but constant intensity and researching the subjectively perceived signal intensity and the participant’s success in detecting the correct shape. This allows better targeting of specific sensations in order to let users perceive concrete signals. It also offers insight into better design of haptic signals to achieve optimal user detection. The results of this investigation were applied in form of a demonstrator, which highlights multiple mid-air haptics and input modalities in different application scenarios.