Haptogram: Ultrasonic Point-Cloud Tactile Stimulation

A Survey of Mid-Air Ultrasonic Tactile Feedback

“…Strength of the effect is an issue, as the mid-air tactile force is only a small fraction of the force thresholds of hardware buttons. A large number of transducers strengthen the effect, but not linearly, due to the limited directivity of the transducers [27]. Large arrays make the device bigger, heavier and more costly.…”

Textured surfaces for ultrasound haptic displays

“…is creates the illusion of simultaneous presentation across the whole hand [5]. ere are several parameters of this rendering method that can be changed to create the perception that the hand is touching something with a distinct texture.…”

“…ey controlled the acoustic eld to create the illusion of mid-air shapes (e.g., cones and cubes), by rendering the outline of the 2D cross-section of the shape as the hand intersects it; e.g., the circular cross-section of a sphere as the hand moves through it. Korres et al [5] rendered haptic shapes by rapidly moving a single point of stimulus to create a "point cloud"; rapid movement created the perception of all points being presented simultaneously. Inoue et al [3] generated an acoustic eld from multiple surrounding arrays, allowing haptic stimuli without the need for frequency modulation (as in [1,4], etc).…”

Point-and-Shake

“…Phased ultrasound arrays have been used to generate a variety of mid-air haptic sensations (e.g., [2,7,8,9,12]), allowing users to experience tactile feedback from gesture systems. They have also been used to direct audio (e.g., Holographic Whisper [16]), to create the illusion of sound coming from remote objects or to direct audio feedback towards specific users.…”