Static and Dynamic Haptic Feedback Using Time Reversal and Electrovibration Stimulations Harald Zophoniasson

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Static and Dynamic Haptic Feedback Using Time Reversal and Electrovibration Stimulations Harald Zophoniasson Static and dynamic haptic feedback using time reversal and electrovibration stimulations Harald Zophoniasson To cite this version: Harald Zophoniasson. Static and dynamic haptic feedback using time reversal and electrovibration stimulations. Vibrations [physics.class-ph]. Université Paris Saclay (COmUE), 2017. English. NNT : 2017SACLX035. tel-02918192 HAL Id: tel-02918192 https://pastel.archives-ouvertes.fr/tel-02918192 Submitted on 20 Aug 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. 1 NNT : 2017SACLX035 Thèse de doctorat de l’Université Paris-Saclay préparée à l’École Polytechnique Ecole doctorale n◦573 Interfaces : approches interdisciplinaires / fondements, applications et innovation Spécialité de doctorat : sciences et technologies industrielles par M. Harald Zophoniasson Retour tactile statique et dynamique utilisant le retournement temporel et l’electrovibration Thèse présentée et soutenue à Palaiseau, le 26 juin 2017. Composition du Jury : Mme. Adriana Tapus Professeur (Examinatrice) ENSTA-ParisTech M. Medhi Ammi Maître de conférence, HDR (Examinateur) Université Paris-Sud, LIMSI M. Thomas Sidler Group Leader (Examinateur) EPFL M. Nazih Mechbal Maître de conférence, HDR (Rapporteur) ENSAM M. Fernando Vidal-Verdú Professeur (Rapporteur) Université de Malaga M. Christian Bolzmacher Ingénieur chercheur (Co-encadrant) CEA LIST, LISA M. Moustapha Hafez Directeur de recherche (Directeur de thèse) CEA LIST, LISA R´esum´e Le retour haptique disponible dans les produits grand public est d'un int´er^etlimit´e pour les interactions tactiles. Il a ´et´ed´emontr´e,par exemple, qu'il est moins efficace que l'utilisation d'un clavier physique pour la saisie de texte. La plupart des utilisa- teurs sont habitu´esau retour haptique rudimentaire des smartphones. Relativement simple, celui-ci ne peut n´eanmoins donner que peu d'informations : signaler silen- cieusement un appel, notifier les messages entrants ou confirmer la frappe de touche sur clavier virtuel. Bien que des am´eliorationsaient ´et´eapport´eesaux technolo- gies haptiques existantes, comme des actionneurs plus performants et des gammes de vibrations plus larges afin de simuler des boutons ou des textures, elles restent limit´ees`aun retour tactile unique. Ceci contrevient `atout usage multi-doigts ou multi-utilisateurs en simultan´es. Ce travail vise `ad´evelopper un retour tactile statique et dynamique sur grande surface (format A4). Les interactions avec les ´ecranstactiles n´ecessitant un retour tactile plus riche et plus performant, deux types de retour compl´ementaires ont ´et´e identifi´esafin de les enrichir. Le retournement temporel des ondes de flexions dans les plaques, retour statique, est ´etudi´eafin de simuler l'appui sur un bouton et l'´electrovibration, retour dynamique, est analys´eeafin de simuler des textures ou de diff´erencierdes zones d'interactions. L'´equationde Kirchhoff d´ecrivant la propagation des ondes acoustiques dans un mat´eriaua permis de d´evelopper un mod`eleanalytique de la r´esolutionspatiale du retournement temporel. Des mesures exp´erimentales sont confront´eesau mod`ele afin de proc´eder`asa validation. Des r`eglesde conception prenant en compte les sp´ecificationsde l'application tactiles envisag´eesont ´elabor´eeset utilis´eespour le d´eveloppement d'un nouveau prototype avec une ´electronique am´elior´eesur une plaque en verre de 1,1 mm d'´epaisseur. Diff´erents types de signaux de commande sont ´etudi´es,avec diff´erentes m´ethodes de quantification (sur un bit ou par modula- tion sigma-delta) et filtrage ou non des fr´equencesaudibles. La quantification sur un bit avec filtrage des fr´equencesaudibles est l'alternative la plus efficiente en terme d'amplitude de d´eplacement g´en´er´eeet de r´eductiondes ´emissionssonores. Des probl´ematiquesd'int´egration,comme le placement des actionneurs et l'homog´en´eit´e de la r´esolutionspatiale et de l'amplitude de d´eplacement sont analys´ees.Les appuis parasites de doigts sur la plaque constitue des perturbations pour la propagation des ondes de flexions, que ce soit en terme de diffraction ou d'amortissement. L’effet de la force d'appui du doigt sur l'amplitude de d´eplacement est donc ´etudi´ee. 6% de perte d'amplitude due `aune force d'appui du doigt de 2 N sur une localisation autre que le point de focalisation, et jusqu’`a30% pour la m^emeforce d'appui sur le 1 point de focalisation, ont ´et´emesur´es. Le seuil de d´etectiond'une focalisation par retournement temporel mesur´esur 10 utilisateurs `a´et´emesur´e`aenviron 10 µm. Il n'est pas influenc´epar la force d'appui de l'utilisateur sur l'´ecran. Bien qu'une unique focalisation d´emontre la faisabilit´edu retournement temporel appliqu´eau retour tactile, elle est jug´ebr`eve et non plaisante selon les utilisateurs. Une r´ep´etitionde focalisations modul´eesen amplitude offre la possibilit´ede g´en´ererun retour tactile enrichi, comme le clic d'un bouton. Des motifs avec des fr´equences de r´ep´etition et des enveloppes diff´erentes sont compar´es. Il appara^ıtqu'une fr´equence de 200 Hz et une enveloppe en sinus cardinal sont les plus plaisants. D'un autre c^ot´e,l'´electrovibration produit des stimuli capables de reproduire une sensation de texture, en modifiant le coefficient de friction entre le doigt et la surface `aexplorer. Sachant que la force ´electrostatique g´en´er´eepar l'´electrovibration d´epend de l'´epaisseurde peau du bout du doigt et que les m´echanorecepteurs ont des seuils de d´etectiond´ependants de la fr´equence,une ´etudeutilisateur a ´et´econduite dans le but de d´eterminerl’influence de la force d'appui sur le seuil de d´etection d'une stimulation par ´electrovibration. Les seuils minimaux ont ´et´eobserv´espour une fr´equencede 240 Hz. La force d'appui, analys´eepar ANOVA, semble avoir une influence limit´eesur les seuils de d´etection. De l´eg`eresdiff´erencessont observ´ees dans les seuils de d´etectionpour des fr´equencessup´erieurs`a240 Hz. Il semble que ceux-ci diminuent avec l'augmentation de la force d'appui. La combinaison des deux approches de stimulations (retournement temporel et ´electrovibration) sur une m^emesurface offrira un retour tactile riche et multi-point pour des boutons et des textures. 2 Remerciements Je voudrais exprimer mes sinc`eresremerciements `ames encadrants, coll`egueset amis qui ont contribu´e`al'accomplissement de ce travail. Tout d'abord je tiens `aremercier vivement Moustapha Hafez, pour m'avoir ac- cueilli au Laboratoire des Interfaces Sensorielles et Ambiantes du CEA, d'abord en tant qu'ing´enieur,puis en tant que doctorant. Comme Directeur de th`ese,il m'a patiemment guid´eau cours de ces ann´eesde th`ese. Je voudrais aussi remercier chaleureusement Christian Bolzmacher, qui a co-encadr´emon travail au CEA, pour avoir aiguill´emon travail tout au long de cette th`ese,avec beaucoup de disponibilit´e et d'int´er^et. Je suis tr`eshonor´eque M. Nazih Mechbal, Ma^ıtrede conf´erence HDR `al'ENSAM et M. Fernando Vidal-verdu, Professeur `al'Universit´ede Malaga aient accept´ed'^etre rapporteurs de ma th`ese. Je remercie ´egalement Adriana Tapus, Professeure `a l'ENSTA-ParisTech et M. Medhi Ammi, Ma^ıtrede conf´erenceHDR `al'Universit´e Paris-Sud, pour avoir accept´ede l'examiner. Je voudrais ensuite remercier mes coll`eguesdoctorants du LISA, en particulier C´edricKnibbe et ses moults remarques aiguis´ees,Valentin Le Guelvouit et Ter- ence Thomas, aux talents pl´ethoriques,Charles Hudin, pour son support th´eorique, Sabrina Pan¨eelset Margarita Anastassova, pour m'avoir guid´edans le monde de l'ergonomie et des tests utilisateurs, Alexandre Patarot et Adrien Jaegy, pour leur bonne humeur communicative, Carlos Rossa, Fanny Le Morellec et Tobias P¨ossinger, pour leurs conseils avis´esde th´esards,Steven Strachan, pour ses critiques construc- tives et le restant de l'´equipe Florent Souvestre, Gw´ena¨elChangeon, Annick Latare, G´erardChalubert, Sylvain Bouchigny, Medhi Boukallel et Michel pour la convivi- alit´e. Je suis en outre, extr^emement reconnaissant `aAlain Truong, ma^ıtred'arts mar- tiaux `al'Ecole´ Polytechnique, ainsi qu'a toute l'´equipe sportive du Lam Son Vo Dao de m'avoir fait d´ecouvrirces enseignements, physiques et mentaux. Merci `aPierre Rizzo et sa soif de convivialit´e, Rivo Ramodiharilafy et ses encouragements, Thanh Li^emNguy^enet sa profonde gentillesse, Catherine Nguyen et sa bonne humeur communicative, Christophe Gorsy et son talent de com´edien, Antigoni Alexandrou, Marine Gu´emas,Jean-Luc Moncel et Marcel Rheinhart. Enfin, merci `aIn`es. 3 Contents 1 Introduction 13 1.1 Scope................................... 14 1.2 Thesis overview.............................. 15 2 State of the art 17 2.1 Introduction................................ 18 2.2 The sense of touch............................ 19 2.2.1 Mechanoreceptors......................... 19 2.2.2 Shape versus texture....................... 20 2.3 Quasi-static interfaces.......................... 21 2.3.1 Pin-array interfaces........................ 21 2.3.2 Deformable surfaces....................... 23 2.4 Dynamic interfaces............................ 25 2.4.1 Lateral motion.......................... 25 2.4.2 Vibrotactile interfaces...................... 27 2.4.3 Variable Friction......................... 31 2.4.4 Electrocutaneous stimulation.................. 39 2.5 Hybrid interfaces............................. 40 2.6 Discussion and motivation of this work................. 42 3 Time Reversal : theory and modelling 45 3.1 Introduction................................ 46 3.2 Theory of Time Reversal......................... 46 3.2.1 Principle.............................. 46 3.2.2 The fundamentals of time reversal...............
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