• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 8
  • 2
  • 1
  • Tagged with
  • 15
  • 15
  • 9
  • 5
  • 5
  • 4
  • 4
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Design and control of a haptic device for minimally invasive surgery simulation / Conception et commande d'un dispositif à rendu haptique dans le cadre de la simulation de chirurgie minimalement invasive

Guiatni, Mohamed 22 June 2009 (has links)
L'objectif principal de cette thèse est de développer une nouvelle interface pour la simulation des procédures de chirurgie mini-invasive. L'interface développée introduit les modalités visuelle, haptique et thermique pour les futures générations de simulateurs et de robots chirurgicaux. La particularité de cette recherche réside dans l'utilisation de la stimulation thermique dans une perspective d'application pour la chirurgie. Dans ce cadre, plusieurs modèles de transfert de chaleur ont été développés, implémentés et évalués pour des applications de téléprésence et de réalité virtuelle. Des sensations intéressantes ont été enregistrées, ce qui a une conséquence directe sur la capacité de distinguer entre des objets dans l'environnement et particulièrement dans le domaine médical où la sensation thermique est en corrélation avec la présence d'anomalies dans certaines maladies. Un nouveau dispositif haptique est conçu et réalisé en analysant les tâches chirurgicales en termes de dextérité, d'espace de travail, de force et de couple exigés. Nous avons tenu compte des exigences générales de conception mécaniques des interfaces haptiques à partir de ce qui a été établi dans la littérature de l'haptique. Le dispositif complet a été interfacé avec un logiciel de simulation en réalité virtuelle (SOFA). Nous avons intégré dans SOFA le module nécessaire pour la simulation thermique. L'intégration était réussie et un scénario de simulation réaliste avec le retour d'information visuel que thermique a été réalisé. Des résultats préliminaires utilisant la simulation complète sont présentés. / The main objective of this thesis focuses on the construction of a new interface for Minimally Invasive Surgery training. This interface incorporates novel broad band sensory modalities that include visual, haptic and thermal technology, into the evolution of the next generation of surgical robotic and surgical simulator. Our particular novelty in this research is in using of thermal stimulation in a MIS applied perspectives. Several thermal exchange models have been designed, implemented and evaluated for telepresence and virtual reality applications. Interesting sensations have been recorded which have a direct bearing on the ability to distinguish between objects in the surrounding environment and particularly in the medical field where temperature sensing correlates with anomalies in some know diseases. A new haptic device is designed and realized by analyzing surgical tasks in terms of required dexterity, workspace, force and torque. The mechanical design constraints have been considered with respect to the general requirements for haptic interface design from what has been well established in the haptics literature. The overall device has been interfaced with an open source VR simulator (SOFA). We added in SOFA the necessary software dealing with thermal simulation using built-in data structure and methods. The integration was successful and a realistic simulation scenario with both visual and thermal feedback was achieved. Preliminary results using the overall simulation are presented.
2

Fluidic Driven Digital Clay

Garth, James Davis 11 January 2007 (has links)
Digital Clay is a tactile array of linear fluidic actuators which provide distributed sensing and position control through the use of an embedded position sensor. The actuator implementation is achieved by two-way hydraulically-driven pistons which are integrated with computer controlled valves. Each actuator is connected to an underlying base plate which is in fluidic communication with high and low pressure reservoirs. The research focuses on the aspects of the fluidics necessary to operate the actuators and control actuation of Digital Clay. The main objectives of this work are the characterization of the fluid flow through the system and the design and implementation of an embedded inductance-based position sensor. Each actuator in Digital Clay is individually addressable and is controlled through the use of a closed-loop proportional integral controller with position feedback from the embedded inductance-based sensor. Also presented in this work is the characterization of an individual fluidic actuator and the realization of a 5x5 tactile array of actuators.
3

Buzzwear: supporting multitasking with wearable tactile displays on the wrist

Lee, Seungyon 27 August 2010 (has links)
On-the-go users' interaction with mobile devices often requires high visual attention that can overtax limited human resources. For example, while attending information displayed on a mobile device, on-the-go users who are driving a car or walking in the street can easily fail to see a dangerous situation. This dissertation explores the benefits of wearable tactile displays (WTDs) to support eyes-free interaction for on-the-go users. The design and implementation of the WTDs are motivated by two principles in mobile user interaction that have been proven both commercially and academically: wristwatch interfaces that reduce the time for device acquisition and tactile interfaces that eliminate the need for visual attention. In this dissertation, I present three phases of design iteration on WTDs to provide the design rationale and challenges. The result of the iterative design is evaluated through in-depth formal investigations with novice users in two experiments: user perception of the tactile stimuli and information throughput in association with multiple tactile parameters, and perception of the tactile stimuli and information throughput when the user is visually distracted. The first experiment explores general human capabilities in perceiving tactile stimuli on the wrist. It reveals that subjects could discriminate 24 tactile patterns with 98% accuracy after 40 minutes of training. Of the four parameters (intensity, starting point, rhythm, direction) that were configured to design the 24 patterns, intensity was the most difficult parameter to distinguish, and temporal variation was the easiest. The second experiment explores users' abilities to perceive incoming alerts from two mobile devices (WTD and mobile phone) with and without visual distraction. The second experiment reveals that when the user was distracted visually, reaction time to perceive the incoming alerts became slower with the mobile phone alert but not with the WTD.
4

Prototype design of cable suspended haptic interface

Moody, Russell H. January 1998 (has links)
No description available.
5

Contributions au développement d'une interface haptique à contacts intermittents / Contributions to the design and control of an encounter-type haptic interface

Gonzalez, Franck 15 April 2015 (has links)
Les interfaces haptiques permettent à un opérateur d'interagir avec un environnement virtuel ou distant via le sens du toucher.La majorité des interfaces de l'état de l'art restent au contact de l’utilisateur pendant toute la durée de la manipulation. La liaison permanente entre le robot et l’opérateur nuit à la qualité de l’interaction, notamment en réduisant la transparence en espace libre. Ce problème est d’autant plus prégnant dans le cadre des interfaces haptiques dextres.Cette thèse a pour objectif d'étudier la possibilité d'augmenter la transparence et le réalisme de l'interaction à travers le développement d’interfaces à contacts intermittents. Il s’agit de déconnecter le robot de l'utilisateur lorsqu’aucun contact avec l’environnement n’est nécessaire. Un état de l’art des performances de la manipulation humaine, des interfaces haptiques dextres ainsi que des travaux relatifs au contact intermittent, est d’abord présenté. Un effecteur plan pour le contact intermittent est ensuite conçu. Il est installé à l’extrémité distale d'une interface haptique et plusieurs solutions sont envisagées pour sa loi de commande. Les performances de dix utilisateurs sont comparées dans le cadre d'une tâche de détection de contact en utilisant d'une part l'effecteur adapté au contact intermittent, d'autre part une interface haptique classique. L'élaboration d'une interface permettant une interaction plus naturelle avec l'environnement est ensuite initiée par l'élaboration d'une méthodologie de choix des zones de contact de la main à prendre en compte dans la conception d'une interface haptique. Des perspectives sont finalement données quant à l'extension de ces résultats à une interface haptique dextre à contacts intermittents. / Haptic interfaces allow an operator to interact with a virtual environment through the sense of touch. Nowadays, most existing interfaces are mechanically connected to the user's hand throughout the simulation. Therefore he or she interacts with the virtual environment by means of a handle. Thus the interaction is neither natural nor intuitive, and the permanent connection between the robot and the operator is the source of perturbations which prevent the interaction from being perfectly transparent and realistic. The goal of this study is to increase transparency as much as possible by disconnecting the robot from the user when s/he is not in contact with the virtual environment, through the design of a dexterous haptic interface allowing for a more natural interaction than with a classical interface taking into account only one contact point. A state-of-the-art of dexterous haptic interfaces and another for intermittent contact devices are first gathered, and the human performances that should be taken into account for the design of a dexterous haptic interface are analysed. A bidirectional end-effector for intermittent contact is then devised. It is set up at the tip of a haptic interface and several solutions are tested for its control. The performances of six users are compared on the context of a contact detection task, first using the intermittent contact end-effector, then using a classical haptic device. A methodology for the choice of the hand contact areas that should be taken into account in the design of a dexterous haptic interface to enhance the naturalness of the interaction is proposed. Finally, some perspectives are given as for the extension of this study for the design of a dexterous encounter-type haptic interface.
6

Improvement and Evaluation of Three Cable Haptic Interface

Shank, Jeffrey A. 05 August 2008 (has links)
No description available.
7

Experimental Analysis on Collaborative Human Behavior in a Physical Interaction Environment

January 2020 (has links)
abstract: Daily collaborative tasks like pushing a table or a couch require haptic communication between the people doing the task. To design collaborative motion planning algorithms for such applications, it is important to understand human behavior. Collaborative tasks involve continuous adaptations and intent recognition between the people involved in the task. This thesis explores the coordination between the human-partners through a virtual setup involving continuous visual feedback. The interaction and coordination are modeled as a two-step process: 1) Collecting data for a collaborative couch-pushing task, where both the people doing the task have complete information about the goal but are unaware of each other's cost functions or intentions and 2) processing the emergent behavior from complete information and fitting a model for this behavior to validate a mathematical model of agent-behavior in multi-agent collaborative tasks. The baseline model is updated using different approaches to resemble the trajectories generated by these models to human trajectories. All these models are compared to each other. The action profiles of both the agents and the position and velocity of the manipulated object during a goal-oriented task is recorded and used as expert-demonstrations to fit models resembling human behaviors. Analysis through hypothesis teasing is also performed to identify the difference in behaviors when there are complete information and information asymmetry among agents regarding the goal position. / Dissertation/Thesis / Masters Thesis Electrical Engineering 2020
8

Control limitation analysis for dissipative passive haptic interfaces

Gao, Dalong 18 November 2005 (has links)
This research addresses the ability of dissipative passive actuators to generate control effects on a passive haptic interface. A haptic display is a human-machine interface that constructs a sensation of touch for the human operator. Applications can be found in various industries, space, medicine and construction etc. A dissipative passive haptic display contains passive actuators that can remove energy from the system by resisting motions in the system. The advantage of a dissipative passive haptic display is better safety compared to an active display. Its disadvantage is the limited control ability from the passive actuators. This research starts with the identification of the control ability and limitations of dissipative passive haptic interfaces. The ability is identified as the steerability, the ability to redirect motions of a manipulator. The force generation analysis of each individual actuator is then selected as an approach to evaluate the steerability. Steerability metrics are defined to evaluate the steerability. Even though non-redundant manipulators dont have desired steerability, optimal steering configurations are found for the best operation. Steerability is improved by redundancy in serial or parallel structures. A theorem is developed to evaluate steerability for redundant manipulators. The influence of system dynamics on their steerabilities is discussed. Previously developed haptic interfaces are evaluated based on their steerabilities. Steerability analysis of three-dimensional haptic interfaces is also given to a limited extent as an extension of the two-dimensional cases. Brakes and clutches are the two types of dissipative passive actuators in this research.
9

The Design and Characterization of a Soft Haptic Interface for Rehabilitation of Impaired Hand Function

January 2018 (has links)
abstract: The human hand comprises complex sensorimotor functions that can be impaired by neurological diseases and traumatic injuries. Effective rehabilitation can bring the impaired hand back to a functional state because of the plasticity of the central nervous system to relearn and remodel the lost synapses in the brain. Current rehabilitation therapies focus on strengthening motor skills, such as grasping, employ multiple objects of varying stiffness and devices that are bulky, costly, and have limited range of stiffness due to the rigid mechanisms employed in their variable stiffness actuators. This research project presents a portable cost-effective soft robotic haptic device with a broad stiffness range that is adjustable and can be utilized in both clinical and home settings. The device eliminates the need for multiple objects by employing a pneumatic soft structure made with highly compliant materials that act as the actuator as well as the structure of the haptic interface. It is made with interchangeable soft elastomeric sleeves that can be customized to include materials of varying stiffness to increase or decrease the stiffness range. The device is fabricated using existing 3D printing technologies, and polymer molding and casting techniques, thus keeping the cost low and throughput high. The haptic interface is linked to either an open-loop system that allows for an increased pressure during usage or closed-loop system that provides pressure regulation in accordance with the stiffness the user specifies. A preliminary evaluation is performed to characterize the effective controllable region of variance in stiffness. Results indicate that the region of controllable stiffness was in the center of the device, where the stiffness appeared to plateau with each increase in pressure. The two control systems are tested to derive relationships between internal pressure, grasping force exertion on the surface, and displacement using multiple probing points on the haptic device. Additional quantitative evaluation is performed with study participants and juxtaposed to a qualitative analysis to ensure adequate perception in compliance variance. Finally, a qualitative evaluation showed that greater than 60% of the trials resulted in the correct perception of stiffness in the haptic device. / Dissertation/Thesis / Masters Thesis Biomedical Engineering 2018
10

IoT in research methods - Interactive Zipper: A study about a tangible interface

Aliyev, Elmar, Xu, Oujun Anders January 2019 (has links)
Användargränssnitt är en viktig del av kommunikationen mellan människor och maskin. Tidigare så kallat människa-datorinteraktion var baserad på användning av hålkort vid kommunikation med datorer, detta ändrades under andra halvan av 1900-talet. Där användningen av det grafiska användargränssnittet och kommandoradsgränssnitt började ta över. I dag finns det flera olika sorters användargränssnitt till flera olika maskiner och enheter, bland annat touch-gränssnittet som används till alla våra smarttelefon. Touch-gränssnittet ansågs som något lättanvänt och gav möjligheter till andra gränssnitt i detta fält. Ett av dem är det haptiska gränssnittet som ger användaren möjligheten att ändra data direkt i verkligheten, inte digitalt.I denna studie presenterar vi ett påtagligt gränssnitt (tangible interface) i form av ett interaktivt blixtlås. Syftet med denna studie är att använda en teknisk uppfinning med ett så kallat Tangible interface för att samla in data i form av en skala och sedan jämföra den med en numerisk skala representerad på papper. Ett experiment användes vid insamlingen av data, den var baserad på två sorters enkäter, det ena var pappersbaserad, medan den andra var baserad på det interaktiva blixtlåset. Hela experimentet avslutades med en utvärdering. Resultatet från experimentet visade att skillnaderna mellan en numerisk skala i form av papper inte skilde sig åt så mycket från det interaktiva blixtlåset. / User Interfaces are necessary for us when communicating with the machines. Early human-computer interactions were based upon the usage of puncture card to communicate with the computer, that later transformed into Graphical User Interfaces and Command Line Interfaces during the latter half of the 20th century. Today there are a lot of different kinds of interfaces for various types of devices, such as the touch interface for our smartphones. Due to the ease and possibilities of using the touch, further development in this area has been desired. An interface that gives the user the possibility to manipulate data in real life, is called a haptic interface. In this paper an interactive zipper is presented as a tangible interface that is part of the haptic interface. The study focuses on how a technological invention with a tangible interface can be used to gather feedbacks in the form of a numeric scale and how it compares to a numeric scale presented on paper. An experiment based on two questionnaires was used to gather the feedbacks, one was paper-based and the other based upon the interactive zipper, and it ended with an evaluation of the interactive zipper. The results showed that there are not any big differences between the numeric scale presented on paper compared to the interactive zipper.

Page generated in 0.0636 seconds