An audio-tactile interface based on dielectric elastomer actuators

This paper presents a concept of a dielectric elastomer actuator (DEA) user interface (smart button) that can sense a user’s touch and provide multi-sensory tactile and acoustic feedbacks through a single electrical input signal. The DEA relies on a multi-layer layout, in which a layer detects user-driven deformations (touches) via custom-built capacitance sensing electronics, and the remaining layers are used to provide actuation (audio-tactile feedbacks). Building upon a recently presented principle, combined tactile and acoustic feedbacks are produced by concurrently exciting different vibration modes of the same active membrane over different frequency ranges. An integrated demonstrator setup is presented, which includes a DEA, an acoustic enclosure, compact sensing and driving electronics. A characterization of the prototype is conducted, including an analysis of the sound pressure level, the force/stroke output at lower working frequencies, the ability to sense deformations with different profiles and produce combined audio-tactile outputs. Compared to previous works on multi-function DEAs, the system presented in this paper provides largely improved sensing performance (with lower working voltage) and features a deeper level of integration (with small-scale custom sensing electronics, and logics embedded onto scalable microcontrollers) and is thus specifically optimised for user-interaction applications. On this end, tests with users are presented here for the first time, which allowed evaluating the subjective perception of the interface’s feedbacks. By means of further optimisation and miniaturisation of the power/sensing electronics and structural components, the layout and multifunction DEA principle presented here might lead, in the future, to the development of DEA-based smart buttons for active surfaces, or portable/wearable user interfaces and communicators.

[1]  Daniel M. Vogt,et al.  A Wearable Textile-Embedded Dielectric Elastomer Actuator Haptic Display. , 2022, Soft robotics.

[2]  G. Moretti,et al.  A Multi‐Mode, Multi‐Frequency Dielectric Elastomer Actuator , 2022, Advanced Functional Materials.

[3]  G. Moretti,et al.  High-frequency voltage-driven vibrations in dielectric elastomer membranes , 2022, Mechanical Systems and Signal Processing.

[4]  H. Shea,et al.  Untethered Feel‐Through Haptics Using 18‐µm Thick Dielectric Elastomer Actuators , 2020, Advanced Functional Materials.

[5]  Stefan Seelecke,et al.  Design and validation of a dielectric elastomer membrane actuator driven pneumatic pump , 2020, Smart Materials and Structures.

[6]  O. Doaré,et al.  Coupled vibro-acoustic modeling of a dielectric elastomer loudspeaker. , 2020, The Journal of the Acoustical Society of America.

[7]  Daniel M. Vogt,et al.  A Wearable Soft Haptic Communicator Based on Dielectric Elastomer Actuators. , 2020, Soft robotics.

[8]  M. Ercan Altinsoy,et al.  Perceptual features of everyday push button sounds and audiotactile interaction , 2020, Acoustical Science and Technology.

[9]  Monika Imschloss,et al.  Feel the Music! Exploring the Cross-modal Correspondence between Music and Haptic Perceptions of Softness , 2019 .

[10]  Bill Kapralos,et al.  Pseudo-haptics: leveraging cross-modal perception in virtual environments , 2019, The Senses and Society.

[11]  Andrew T. Conn,et al.  A Magnetically Coupled Dielectric Elastomer Pump for Soft Robotics , 2019, Advanced Materials Technologies.

[12]  Federico Carpi,et al.  Enabling portable multiple-line refreshable Braille displays with electroactive elastomers. , 2018, Medical engineering & physics.

[13]  M. Moallem,et al.  On the electrical safety of dielectric elastomer actuators in proximity to the human body , 2017 .

[14]  Micah Hodgins,et al.  Effect of screen printing parameters on sensor and actuator performance of dielectric elastomer (DE) membranes , 2017 .

[15]  Alexandre Poulin,et al.  Flexible Zinc–Tin Oxide Thin Film Transistors Operating at 1 kV for Integrated Switching of Dielectric Elastomer Actuators Arrays , 2017, Advanced materials.

[16]  G. Rizzello,et al.  Closed loop control of dielectric elastomer actuators based on self-sensing displacement feedback , 2016 .

[17]  K. Bertoldi,et al.  Dielectric Elastomer Based “Grippers” for Soft Robotics , 2015, Advanced materials.

[18]  Ja Choon Koo,et al.  Tactile display with rigid coupling based on soft actuator , 2015 .

[19]  I. Gavrilovich,et al.  Rollable Multisegment Dielectric Elastomer Minimum Energy Structures for a Deployable Microsatellite Gripper , 2015, IEEE/ASME Transactions on Mechatronics.

[20]  Luca Turchet,et al.  SoleSound: Towards a novel portable system for audio-tactile underfoot feedback , 2014, 5th IEEE RAS/EMBS International Conference on Biomedical Robotics and Biomechatronics.

[21]  Daniele Mazzei,et al.  Wearable Wireless Tactile Display for Virtual Interactions with Soft Bodies , 2014, Front. Bioeng. Biotechnol..

[22]  Mendel Kleiner,et al.  Acoustics and Audio Technology , 2014 .

[23]  Kazuho Ono,et al.  A lightweight push-pull acoustic transducer composed of a pair of dielectric elastomer films. , 2013, The Journal of the Acoustical Society of America.

[24]  A. York,et al.  Experimental comparison of bias elements for out-of-plane DEAP actuator system , 2013 .

[25]  G. Vassura,et al.  Optimal Synthesis of Conically Shaped Dielectric Elastomer Linear Actuators: Design Methodology and Experimental Validation , 2011, IEEE/ASME Transactions on Mechatronics.

[26]  B. Hannaford,et al.  Perceptual thresholds for single vs. Multi-Finger Haptic interaction , 2010, 2010 IEEE Haptics Symposium.

[27]  Hyoukryeol Choi,et al.  Development of Soft-Actuator-Based Wearable Tactile Display , 2008, IEEE Transactions on Robotics.

[28]  Larry S. Davis,et al.  Rendering localized spatial audio in a virtual auditory space , 2004, IEEE Transactions on Multimedia.

[29]  Guggi Kofod,et al.  Dielectric elastomer actuators , 2001 .