A atividade exploratoria em tarefas de ancoragem haptica exerce um efeito positivo em tarefas desafiadoras ao controle postural. A melhora ou reducao da instabilidade postural em tarefas de ancoragem foi comprovada em diversos grupos (i.e., adultos jovens, adultos idosos, criancas, e participantes com deficiencia) e condicoes experimentais (i.e., variados niveis de complexidade de tarefa postural). O problema deste estudo foi analisar em contextos de tarefas posturais se existe uma relacao entre o desequilibrio homeostatico provocado pelo exercicio fisico de esforco maximo (que afeta o sistema postural pelo impacto no sistema autonomo) e o sistema haptico (que integra adicional estrategia de controle voluntario ao sistema postural). O objetivo do nosso estudo foi testar se a informacao haptica proporcionada pelo uso do sistema ancora exibe efeitos imediatos de atenuacao dos niveis de instabilidade postural aumentada pela fadiga geral decorrente do exercicio fisico maximo. O sistema ancora incorpora atividade exploratoria simultanea a execucao de uma tarefa postural desafiadora. O contexto de ancoragem inclui o manejo de dois cabos flexiveis com cargas anexas em suas extremidades que possibilita a exploracao haptica. Neste estudo, dois grupos foram compostos, um grupo experimental com vinte e tres adultos jovens fisicamente ativos e um grupo controle composto de dez adultos jovens. Ambos os grupos realizaram duas sessoes experimentais (com ancora; sem ancora) com tarefas de controle postural. Para o grupo experimental, as duas sessoes consistiram em: a. uma tarefa de equilibrio antes do esforco fisico, b. um protocolo incremental de esforco, e c. tarefas de equilibrio apos o protocolo de esforco realizados em 4 diferentes momentos ate 15 minutos. Para a inducao do esforco fisico, utilizamos um protocolo incremental maximo em esteira ergometrica, e as duas sessoes experimentais foram realizadas em dias diferentes com prazo maximo entre elas de 14 dias. O grupo controle realizou as mesmas sessoes, entretanto o protocolo de inducao ao esforco fisico foi substituido por um periodo equivalente de descanso. O objetivo da existencia do grupo controle foi verificar a presenca de um efeito de aprendizagem durante a execucao das tarefas. Os resultados para o grupo experimental das variaveis relacionados ao deslocamento do CT, no dominio do tempo mostraram que a informacao haptica proveniente do sistema ancora atenuou a instabilidade postural durante condicoes de tarefas de controle postural onde o participante encontrava-se sob os efeitos da fadiga. Em todas as condicoes experimentais, o exercicio fisico maximo na esteira produziu um aumento na oscilacao postural, como esperado. Entretanto, quando a informacao haptica foi associada na tarefa experimental, a oscilacao postural foi significativamente diminuida. Embora a informacao haptica tenha atenuado significativamente os efeitos da fadiga geral sobre os niveis de oscilacao postural, a velocidade de recuperacao dos valores basais da oscilacao postural foi, na condicao de ancoragem, reduzida dada sua proximidade com os valores de oscilacao tipicos da tarefa sem a fadiga. Os resultados do grupo controle demonstraram que as tarefas utilizadas nao foram suficientes para promover um efeito de aprendizagem. O organismo a partir de estimulos de curto prazo compensou os efeitos de degradacao do equilibrio provocados pela fatiga. A informacao haptica foi util para o sistema de controle da postura compensar os efeitos de perturbacao causados pela fadiga. / Exploratory activity during haptic anchoring has a positive effect during challenging postural control tasks. In such case, improvement of postural stability has been demonstrated in a variety of groups (i.e., young adults, older adults, children, and disabled participants) and experimental conditions (i.e., different levels of postural task complexity). The issue of this study is to analyze in contexts of postural tasks whether there is a relation between the homeostatic imbalance caused by maximal physical exertion (that affects the postural system by the impact on the autonomic system) and the haptic system (which integrates additional strategy of voluntary control to the postural system). The purpose of our study was to test whether the haptic information provided by the use of the anchor system exhibits immediate effects on attenuation of postural instability levels increased by general fatigue caused by maximal physical exertion. The anchor system incorporates simultaneous exploratory activity to the execution of a challenging postural task. The anchoring context includes the handling of two flexible cables with loads attached at their ends that enable haptic exploration. In this study, two groups were composed, an experimental group with twenty-three physically active young adults and a control group composed of ten young adults. Both groups performed two experimental sessions (with anchor, without anchor) with tasks of postural control. For the experimental group, the two sessions consisted of: a. balance tasks before physical effort, b. exposure to an incremental exercise protocol, and c. balance tasks after the exercise protocol distributed in 4 periods up to 15 minutes. To induce physical exertion, we used a maximum incremental protocol on a treadmill, and two experimental sessions were conducted on different days with a maximum of 14 days between them. The control group performed the same sessions, however the protocol of induction to physical effort was replaced by an equivalent period of rest. The aim of the control group was to verify the presence of a learning effect during the execution of the tasks. The results for the experimental group of variables related to CT displacement in time domain showed that haptic information from the anchor system attenuated postural instability during conditions of postural control tasks where the participant was under effects of fatigue. In all experimental conditions maximal physical exercise on the treadmill increased postural oscillation, as expected. However, when the haptic information was associated with the experimental task, the postural sway was significantly decreased. Although haptic information significantly attenuated the effects of general fatigue on postural sway the rate of recovery of the basal values of the postural sway was, in the anchoring condition, reduced because of its proximity to the typical oscillation values of the task without the fatigue. The results of the control group demonstrated that the tasks used were not enough to promote a learning effect. The organism from short-term stimuli compensated for the effects of balance degradation caused by fatigue. Haptic information was useful for the posture control system to compensate for the disturbance effects caused by fatigue.

Il est important pour les robots de pouvoir reconnaître les objets rencontrés dans la vie quotidienne afin d’assurer leur autonomie. De nos jours, les robots sont équipés de capteurs sophistiqués permettant d’imiter le sens humain du toucher. C’est ce qui permet aux robots interagissant avec les objets de percevoir les propriétés (telles la texture, la rigidité et la matière) nécessaires pour leur reconnaissance. Dans cette thèse, notre but est d’exploiter les données haptiques issues de l’interaction robot-objet afin de reconnaître les objets de la vie quotidienne, et cela en utilisant les algorithmes d’apprentissage automatique. Le problème qui se pose est la difficulté de collecter suffisamment de données haptiques afin d’entraîner les algorithmes d’apprentissage supervisé sur tous les objets que le robot doit reconnaître. En effet, les objets de la vie quotidienne sont nombreux et l’interaction physique entre le robot et chaque objet pour la collection des données prend beaucoup de temps et d’efforts. Pour traiter ce problème, nous développons un système de reconnaissance haptique permettant de reconnaître des objets à partir d'aucune, de une seule, ou de plusieurs données d’entraînement. Enfin, nous intégrons la vision afin d’améliorer la reconnaissance d'objets lorsque le robot est équipé de caméras. / Recognizing surrounding objects is an important skill for the autonomy of robots performing in daily-life. Nowadays robots are equipped with sophisticated sensors imitating the human sense of touch. This allows the recognition of an object based on information ensuing from robot-object physical interaction. Such information can include the object texture, compliance and material. In this thesis, we exploit haptic data to perform haptic recognition of daily life objects using machine learning techniques. The main challenge faced in our work is the difficulty of collecting a fair amount of haptic training data for all daily-life objects. This is due to the continuously growing number of objects and to the effort and time needed by the robot to physically interact with each object for data collection. We solve this problem by developing a haptic recognition framework capable of performing Zero-shot, One-shot and Multi-shot Learning. We also extend our framework by integrating vision to enhance the robot’s recognition performance, whenever such sense is available.

Au cours de la dernière décennie, les écrans tactiles sont devenus un standard des interfaces homme-machine. Cependant, malgré leurs nombreux atouts, ils manquent encore de sensations tactiles : quelque soit le contenu visuel, ils restent plats, lisses, rigides et immobiles sous le doigt. Dans cet ouvrage, nous examinons les moyens permettant aux écrans tactiles de nous toucher en retour, et de produire des sensations tactiles variées associées à des images. Premièrement, nous proposons un nouveau format de données haptiques qui fournit une description haptique générique d'un objet virtuel indépendamment de la technologie de rendu. Ce format est destiné à s’intégrer aisément dans les processus de création de contenu audiovisuel, et à être facilement manipulé par des non-spécialistes dans des contextes multidisciplinaires. Ensuite, nous abordons le challenge de produire des sensations haptiques variées avec une complexité technique limitée, grâce à notre nouvelle approche appelée "KinesTouch". Nous proposons en particulier un nouvel effet de frottement basé sur des déplacements latéraux augmentant ou diminuant la vitesse de glissement entre le doigt et l'écran. Enfin, nous présentons "Touchy", une méthode appliquant les principes pseudo-haptiques aux interactions sur écran tactile. Nous proposons un ensemble d'effets pseudo-haptiques traduisant visuellement des propriétés telles que de la rugosité, de la rigidité ou du frottement par les vibrations, les déformations et la trajectoire d'un curseur circulaire affiché sous le doigt de l'utilisateur. Nous appliquons également ces effets à des scènes 3D et traitons des différences entre les méthodes de rendu de contenu 2D ou 3D. / Touchscreens have largely spread out over the last decade and have become one of the most ordinary human-machine interface. However, despite their many assets, touchscreens still lack of tactile sensations: they always feel flat, smooth, rigid and static under the finger, no matter the visual content. In this work, we investigate how to provide touchscreens with the means to touch us and express a variety of image-related haptic features. We first propose a new format for haptic data which provides a generic haptic description of a virtual object without prior knowledge on display hardware. This format is meant to be seamlessly integrated in audiovisual content creation workflows, and to be easily manipulated by non-experts in multidisciplinary contexts. Then, we address the challenge of providing a diversity of haptic sensations with lightweight actuation, with the novel approach called “KinesTouch”. We propose in particular a novel friction effect based on large lateral motion that increases or diminishes the sliding velocity between the finger and the screen. Finally, we introduce “Touchy”, a method to apply pseudo-haptic principles to touchscreen interactions. We present a set of pseudo-haptic effects which evoke haptic properties like roughness, stiffness or friction through the vibrations, stretches, dilatations and compressions of a ring-shaped cursor displayed under the user’s finger. We extend these effects to 3D scenes, and discuss the differences between 2D and 3D content enhancement.

<p>How does haptic feedback during human-virtual character interaction affect participant physiological responses in virtual reality? In this between-subjects study, haptic feedback and non-haptic feedback conditions in which virtual characters bump into the participant who is immersed in a virtual environment are compared. A questionnaire was developed to determine the influence of haptic feedback on presence, embodiment, positive and negative affect, interaction with virtual characters, and haptic feedback realism, among other more exploratory concepts. These exploratory variables include engagement, flow, comfort with virtual characters, comfort with virtual characters’ appearance, realism of virtual character interaction, realism of haptic feedback, and virtual reality sickness. Physiological data was collected using galvanic skin response (GSR) to investigate the influence of haptic feedback on physiological arousal during human-virtual character interaction. Five conditions were developed (no haptic feedback, full and half intensity, incorrect position, and delayed timing). Significant differences were found in embodiment, realism of virtual character interaction, haptic feedback realism, and GSR amplitude after the first interaction with the virtual character. These results may inform future virtual reality studies that investigate haptic feedback during human-virtual character interaction and/or arousal via GSR data, as well as advise studies that seek to correlate self-report responses with physiological data. </p>

La robotique a fait progresser les interventions chirurgicales, avec des interventions moins invasives, une manipulation d’instruments plus précise et une meilleure dextérité. Néanmoins, le manque de retour haptique sur les plates-formes chirurgicales existantes aujourd’hui rend délicat l’accomplissement des gestes chirurgicaux et par conséquent augmente le risque de ces procédures. Avec l’introduction d’un retour haptique, les robots chirurgicaux sont conçus avec une approche de télé-opération bilatérale. Le retard, inhérent à cette approche, est crucial car même un petit retard pourrait déstabiliser le système. En pratique, le retard est inévitable, notamment pour les robots miniaturisés avec communication sans fils. Pour résoudre les problèmes liés à l’instabilité induite par le retard et rendre passif le canal de communication, l’approche de wave variable transformation (WVT) a été proposée. Néanmoins, les performances de suivi sont compromises à cause de la conservation de la condition de passivité. Dans cette thèse, une nouvelle approche de compensation basée sur la structure de wave variable, et considérant moins de condition de conservation est proposée afin d’améliorer les performances de suivi en position, en vitesse et en force. Pour garantir la passivité du système global, une approche énergétique (energy reservoir based regulators) est développée pour ajuster les termes de WVT avec une analyse rigoureuse. La méthode proposée permet d’améliorer les performances de suivi avec uniquement un retard de transmission dans un seul sens. Pour faciliter davantage les procédures chirurgicales, notamment les microchirurgies, deux facteurs d’échelle ont été rajoutés à l’approche de compensation. Une analyse de passivité a été par ailleurs menée en considérant la transparence du système. Les performances de suivi peuvent être obtenues si et seulement si les conditions de passivité et de transparence sont satisfaites. Les approches de compensation, avec et sans mise à l’échelle, ont été vérifiées à travers des simulations et des évaluations expérimentales. / Robotic technology has advanced the surgical procedures in terms of reduced trauma, more accurate manipulation and enhanced dexterity. However, the lack of haptic feedback on existing surgical robotic platforms makes it impossible for the surgeon to feel the operative site,and thus increases the risks of surgical procedures. With the introduction of haptic feedback, the surgical robots are design in bilateral teleoperation way. Time delay in bilateral teleoperation is crucial because even small time delay may destabilize the system. In practice, time delay is unavoidable, e.g. wireless communication miniaturized surgical robots, internet based robotic-assisted telesurgery and transmission of big amount of information, etc. In order to solve the instability caused by time delay in bilateral teleoperation, wave variable transformation (WVT) method has been proposed to passivate the delayed communication channel. However, the tracking performances are compromised due to the conservative passivity condition. In this thesis, a new wave variable compensation (WVC) structure with less conservative condition is proposed to enhance the velocity/position and force tracking performances. In order to guarantee the passivity of the whole system, energy reservoir based regulators are designed to adjust the WVC terms in the proposed structure with rigorous analysis. The WVC is able to achieve tracking performance with only single trip time delay. To better facilitate the surgical procedures, e.g. the microsurgeries, a scaled WVC structure is also developed by adding two scaling factors to the WVC structure. Passivity analysis on the scaled WVC is conducted with consideration of system transparency. Scaled tracking performance can be obtained as long as the two obtained passivity and transparency conditions are satisfied. The proposed WVC and scaled WVC have been verified through simulation and experimental studies.

O presente estudo buscou investigar se participantes videntes apresentaram a mesma performance nos julgamentos de comprimentos de linha do que participantes videntes vendados, cujas estimativas foram realizadas através da percepção tato-cinestésica háptica). Além disso, buscou-se conhecer se esta relação é mantida nas três diferentes formas de comprimentos de linha apresentados: reta, em L e curva e na utilização de dois métodos psicofísicos diferentes: estimação de magnitude e estimação de categoria. A amostra foi constituída por 120 participantes com visão normal, de ambos os sexos, com idade entre 18 e 35 anos, divididos em dois grupos de acordo com a modalidade sensorial: vidente e não vidente (vidente vendado). Os experimentos consistiram em: 1. estimação de magnitude visual; 2. estimação de magnitude não-visual; 3. estimação de categoria visual e 4. estimação de categoria não-visual. Trinta participantes se submeteram a cada um destes experimentos, divididos em três grupos de 10, de acordo com a forma dos comprimentos. Análises estatísticas permitiram concluir que: 1) comprimentos de linha diferentes foram percebidos como diferentes em todos os grupos; 2) a forma dos comprimentos de linha não interferiu nos julgamentos dos participantes; 3) a modalidade sensorial não interferiu nos julgamentos de comprimentos de linha dos participantes e 4) a relação entre o comprimento físico e a estimativa foi mantida em ambos os métodos utilizados, estimação de magnitude e estimação de categoria. / The present study aimed to investigate if sighted participants presented the same performance in the judgements of length of line as blindfolded sighted participants, whose estimates were performed through the touch-cinestesic (haptic) perception. Besides, it aimed to know if this relation is kept in the three different shapes of line length presented: straight; L-shaped and curved and in the use of two different psychophysics methods: magnitude estimation and category estimation. The sample was composed by 120 participants with normal sight, of both sexes, aged between 18 and 35, divided into two groups according to the sensorial mode: sighted participants and blindfolded sighted participants. The experiments consisted in: 1. visual magnitude estimation; 2. non-visual magnitude estimation; 3. visual category estimation and 4. non-visual category estimation. Thirty participants were submitted to each of them, divided into three groups of ten, according to the shape of the lengths. Statistic analysis allowed to conclude that: 1) different line lengths were perceived different in all the groups; 2) the shape of the line lengths did not interfere in the judgements of the participants; 3) the sensorial mode did not interfere in the participants’ judgements of line lengths; 4) the relation between physical length and estimate was kept in the use of both methods: magnitude estimation and category estimation.

Desde o final da década de 1980, um gênero de imagens denominado de fotografia brasileira contemporânea vai se delineando no campo artístico. Artistas como Rosângela Rennó, Claudia Andujar e Miguel Rio Branco produzem fotografias que se inserem no âmbito da arte contemporânea inovando no modo de construção da imagem fotográfica. O presente trabalho elege dois fotolivros de Rio Branco para investigar algumas das inovações no modo como a fotografia articula uma significação mais sensível. O ponto de vista teórico adotado para a análise dessas imagens deriva dos estudos semióticos greimasianos, que passam a dar conta desde a década de 1990 do estudo de textos poéticos que exaltam a sensibilidade. Além de uma maior consideração do corpo como base para a apreensão do sentido nos textos visuais, a semiótica avança na diferenciação de níveis de análise do texto. Tendo em vista a hierarquização proposta por Fontanille em 2007, esta pesquisa investiga as principais estratégias enunciativas empregadas por Miguel Rio Branco na construção do texto imagético, acentuando o papel da organização plástica e particularizando o papel da textura na criação de uma aproximação sensível do texto ao enunciatário. Leva-se em consideração ainda, o papel do objeto fotolivro na apreensão das imagens, como importante suporte que evoca corporalmente o observador. No nível das cenas predicativas, pontua-se algumas práticas enunciativas que vão se sedimentando ao longo do tempo na fotografia artística. A escolha de temas mais cotidianos e o retrato de objetos banais subvertem inicialmente o estatuto artístico, mas terminam por caracterizar uma postura enunciativa que convoca o enunciatário a conhecer de modo sensível a apreensão do banal. Essas estratégias demonstram, portanto, a defesa de formas de vida que prezam pela presença mais sensível do homem no mundo, valorizando o engajamento sensível de todo o corpo na relação com os objetos e com os textos artísticos. A consideração dos textos, objetos, cenas predicativas, estratégias e modos de vida permite ao analista uma visão mais ampla sobre os papéis que a imagem fotográfica perfaz. Uma análise mais aprofundada da obra de Rio Branco permite, ainda, explorar os efeitos sensíveis de estratégias enunciativas como a construção de metáforas visuais por meio de dípticos. Explora-se também, o papel da textura na exaltação da superfície dos objetos e valorização de uma sensibilidade háptica, na qual a sinestesia se torna a base para que o visual encontre relações possíveis com o tato. / Since the late 1980s, a genre of images called contemporary brazilian photography will be outlining in the artistic field. Artists like Rosângela Rennó, Claudia Andujar and Miguel Rio Branco had produced photographs that are within the scope of contemporary art, innovating the construction of the photographic image. This research elects two photobooks from Rio Branco to investigate some of the innovations in the way photography articulates a more sensible meaning. The theoretical point of view adopted for the analysis of these images derives from Greima`s semiotic studies, bringing to account since the 1990s the study of poetic texts that exalt the sensitivity. In addition to the greater consideration of the body as the basis for the apprehension of meaning in visual texts, semiotics advances in differentiating levels of text analysis. Given the hierarchy proposed by Fontanille in 2004, this research investigates the main strategies employed by Miguel Rio Branco in the construction of imagistic text, highlighting the role of plastic organization and individualising the role of texture in creating a sensitive approach to the text enunciatee. It takes into account also the role of the photobook object in the apprehension of images, how important that support bodily evokes the observer. At the level of predicative scenes, points up some enunciative practices that will solidifying over time in artistic photography. The choice of most everyday topics and the portrait of banal objects initially subvert the artistic status, but they eventually characterize an enunciative stance that calls the sensibility of the enunciatee to apprenhend the banal. These strategies, therefore, demonstrate the defense of life forms which have the most sensitive presence in the world, valuing sensitive engagement of the whole body in relation to objects and artistic texts. The consideration of texts, objects, predicative scenes, strategies and ways of life allows the analyst a broader view on the roles that the photographic image totals. Further analysis of the work of Rio Branco also explores the sensitive effects of enunciative strategies such as constructing visual metaphors through diptychs. It also explores the role of texture in the exaltation of the surface of objects and appreciation of a haptic sensitivity, in which synesthesia becomes the basis for the visual find possible relations with tact.

An unhealthy reliance on vision alone, fed by pervasive, doctored, hyperreal imagery in the mass media, suppresses a more balanced use of other senses, reinforcing superficial beauty standards. Trapped by an uncritical preference for the visually “perfect” and harmonious, people increasingly seek to remove physical attributes they consider “imperfect,” without first considering how these “imperfections” benefit and distinguish them as unique individuals. This thesis addresses superficial beauty standards by shifting focus from singularly visual experience to a more nuanced sensory aesthetic that also considers haptic qualities. Through a combination of research writing and targeted making, my work examines society’s understanding of flaws and imperfections by strategically embedding natural qualities of texture and randomness—blemishes—into ceramics, a medium treated as analogous to human skin. The resulting tools and objects, designed to support a healthy, ritualized daily skincare routine, examine beauty through the lens of wabi-sabi—the philosophy of things imperfect, impermanent, and incomplete.

<p>The purpose of this report is to cover the procedure of creating and explaining how to use a tool kit that allows the haptic Application Programming Interface (API) H3D from SenseGraphics to be used in conjunction with an advanced physics simulator from Meqon. Both haptic applications and physics engines have developed rapidly the last couple of years but they are rarely used together. If such a connection would be created it would be possible to interact with complex environments in a new way and a variety of haptic applications can be produced.</p><p>The physics engine from Meqon has gained recognition for its abilities to produce realistic results due to efficient implementation of collision detection system, friction models and collision handling, among other things. H3D is a completely open source API that is based on standards such as OpenGL and X3D. H3D consists of a data base containing nodes, an XML parser to extract a scene graph from the data base and functionality to produce a graphic and haptic interface.</p><p>The tool kit produced in this thesis is an extension to H3D. A fundamental function of the tool kit is to communicate with the Meqon system and still be a part of the H3D structure. The Meqon system has a modular structure where each module has its own abilities. Only the rigid body module is utilised by the tool kit, which however is the most important module. It is possible to define global settings of the engine and rigid body module, add rigid bodies with several elements and insert constraints on the motion of the rigid bodies into the engine. All of these operations are done from the X3D file format that H3D uses, thus letting all functionality of the H3D system available.</p>

Modern medical imaging techniques provide an increasing amount of high-dimensional and high-resolution image data that need to be visualized, analyzed, and interpreted for diagnostic and treatment planning purposes. As a consequence, efficient ways of exploring these images are needed. In order to work with specific patient cases, it is necessary to be able to work directly with the medical image volumes and to generate the relevant 3D structures directly as they are needed for visualization and analysis. This requires efficient tools for segmentation, i.e., separation of objects from each other and from the background. Segmentation is hard to automate due to, e.g., high shape variability of organs and limited contrast between tissues. Manual segmentation, on the other hand, is tedious and error-prone. An approach combining the merits from automatic and manual methods is semi-automatic segmentation, where the user interactively provides input to the methods. For complex medical image volumes, the interactive part can be highly 3D oriented and is therefore dependent on the user interface. This thesis presents methods for interactive segmentation and visualization where true 3D interaction with haptic feedback and stereo graphics is used. Well-known segmentation methods such as fast marching, fuzzy connectedness, live-wire, and deformable models, have been tailored and extended for implementation in a 3D environment where volume visualization and haptics are used to guide the user. The visualization is accelerated with graphics hardware and therefore allows for volume rendering in stereo at interactive rates. The haptic feedback is rendered with constraint-based direct volume haptics in order to convey information about the data that is hard to visualize and thereby facilitate the interaction. The methods have been applied to real medical images, e.g., 3D liver CT data and 4D breast MR data with good results. To provide a tool for future work in this area, a software toolkit containing the implementations of the developed methods has been made publicly available.