An acoustic multi-touch sensing method using amplitude disturbed ultrasonic wave diffraction patterns

Yuan Liu (1) , Jean-Pierre Nikolovski (2) , Nazih Mechbal (1) , M Hafez (2) , Michel Vergé (1)

1 LMSP - Laboratoire de Mécanique des Systèmes et des Procédés
2 LIS - Laboratoire Interfaces Sensorielles

This paper proposes an acoustic multi-touch tactile sensing method. The proposed method is based on an amplitude disturbed ultrasonic wave diffraction pattern. An A0 Lamb wave transmitted in a thin finite copper plate is processed to provide tactile information, for one or two fingers. A touch event is localized by identifying the diffraction signals among a database of diffracted Lamb wave references. Statistic models are used to improve the localization reliability. An artificial silicone finger is used in the calibration procedure. This touch interface is evaluated as a 2-touch interface.

Mots clés: Lamb waves; Tactile; Multi-touch; Diffraction; Pattern recognition

Domaines: Acoustique [physics.class-ph]; Automatique / Robotique; Vibrations [physics.class-ph]; Traitement du signal et de l'image [eess.SP]

Yuan Liu, Jean-Pierre Nikolovski, Nazih Mechbal, M Hafez, Michel Vergé. An acoustic multi-touch sensing method using amplitude disturbed ultrasonic wave diffraction patterns. Sensors and Actuators A: Physical , 2010, 162 (2), pp.394-399. ⟨10.1016/j.sna.2010.03.020⟩. ⟨hal-01102732⟩