MVibCode: Multi-Channel Vibrotactile Codec Using Hierarchical Perceptual Clustering.

To achieve convincing remote vibrotactile experiences, it is necessary to transmit a large number of signal channels corresponding to dense interaction points on the human skin. This leads to a dramatic increase in the amount of data to be transmitted. In order to cope with these data efficiently, vibrotactile codecs have to be used to reduce the data rate demands.

Confinement of Vibrotactile Stimuli in Narrow Plates: Principle and Effect of Finger Loading.

On a touch surface, providing a local vibrotactile feedback enables multiuser and multitouch interactions. While the vibration propagation usually impedes this localization, we show in this article that narrow strip-shaped plates constitute waveguides in which bending waves below a cut-off frequency do not propagate. We provide a theoretical explanation of the phenomenon and experimental validations.

Multitouch Vibrotactile Feedback on a Tactile Screen by the Inverse Filter Technique: Vibration Amplitude and Spatial Resolution.

Nowadays, tactile surfaces, such as smartphones, provide haptic feedback to signify that a task has been performed correctly or more generally to enrich the interaction. However, this haptic feedback induces vibrations in the surface that propagate to the whole surface, reverberate and attenuate, thus making multi-finger interaction, with different feedbacks, difficult. Recently, the Inverse Filter Method has been proposed to control the propagation of these vibrations, and thus enable to product localized multitouch on a glass surface.

Localized Tactile Feedback on a Transparent Surface through Time-Reversal Wave Focusing.

This article addresses the problem of producing independent tactile stimuli to multiple fingers exploring a transparent solid surface without the need to track their positions. To this end, wave time-reversal was applied to re-focus displacement impulses in time and in space at one or several locations in a thin glass plate. This result was achieved using ultrasonic bending waves produced by a set of lamellar piezoelectric actuators bonded at the periphery of the plate.