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  • 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.
101

Desenvolvimento de um projeto de experimentos para a caracterização de sinais mioelétricos através do uso de regressão logística

Cene, Vinicius Horn January 2016 (has links)
Através dos dispositivos e técnicas desenvolvidas na área da Instrumentação Biomédica é possível oferecer um tratamento ou de forma geral soluções que permitam uma vivência mais plena em sociedade para pessoas que possuem algum tipo de deficiência ou doença. Com o aumento da capacidade computacional nos últimos anos foi possível desenvolver muitas técnicas e dispositivos apoiados em processamento digital de sinais e há um grande interesse pelo desenvolvimento de interfaces mais naturais, como sinais biológicos para o controle de próteses e dispositivos. Este trabalho tem por objetivo apresentar o desenvolvimento de um método de Inteligência Computacional baseado em Regressão Logística capaz de classificar 17 movimentos do segmento mão-braço realizados pelos voluntários do estudo através do processamento do sinal mioelétrico (SME) adquiridos dos sujeitos em questão. Adicionalmente é realizada uma avaliação da influência de alguns dos canais, características do sinal e movimentos executados na taxa de acerto global. Para a realização do sistema foi utilizado um aparato experimental capaz de adquirir os SME através de 12 canais utilizando eletrodos não invasivos e posteriormente digitalizá-los. Logo após efetua-se a extração das três características utilizadas no trabalho, que servem de entrada para o método de Regressão Logística. Para este estudo foram processados três bancos de dados que perfazem um total de 50 voluntários. A taxa média de acerto alcançada foi de 70,1%, considerando todas as variações de testes realizados enquanto a média para os melhores casos de cada variação de entrada realizada foi de 92,5%. / Through the devices and techniques developed in the field of Biomedical Instrumentation commonly is possible to offer treatment or solutions to provide a more pleasurable experience in society for people who have a disability or illness. With increasing computing capability in recent years, it has been possible to develop many techniques and devices supported by digital signal processing, and there is a great interest in the development of more natural interfaces, such as biological signals for the control of devices and prostheses. This work aims to present the development of a computational intelligence method based on Logistic Regression able to classify 17 movements of the hand-arm segment performed by the subjects of this study through the processing of the myoelectric signal (SME) acquired from the subject in question. Additionally, an assessment of the influence of some of the combination of the channels, signal characteristics and movements performed in the overall hit rate is additionally performed. To conduct the system has built an experimental apparatus able to acquire the SME through 12 channels using non-invasive electrodes and scan them. Thereafter there is a three features extraction from the signal which serves as input to the Logistic Regression method. For this study were processed three databases that compose 50 volunteers. The average hit rate achieved was 70.1%, considering all tests variations while the average for the best cases for each input variation performed was 92,5 %.
102

Acionamento e controle de um dedo de uma prótese para membro superior com realimentação proprioceptiva de força e temperatura

Vanderlei de Oliveira Del Cura 14 June 2005 (has links)
Este trabalho visa contribuir para redução do grau de rejeição de próteses para membros superiores, tornando-as mais funcionais e eficientes. Tais propósitos são almejados por meio do estudo centrado no desenvolvimento de uma plataforma eletrônica de controle e nos demais constituintes de uma prótese. Dentre eles estão os atuadores, sensores, mecanismos e o programa de gerenciamento, que integra todos os componentes para as ações da prótese. Para esse trabalho foi usado somente um dedo para a execução de todos os testes, sendo esse dedo compatível com o desenvolvimento de uma prótese antropomórfica multifunção. O paciente comanda as ações da prótese ao enviar suas decisões à ela por meio de sinal mioelétrico, mas as ações da mesma são executadas de forma inconsciente. Isto é possível devido ao programa de gerenciamento, que controla os movimentos antropomórficos a partir de trajetórias definidas e também pelas informações de sensações de força e temperatura para o paciente, realimentação proprioceptiva. / This work contributes to minimize the rejection level of upper limb prosthesis, keeping it more function and efficient. This achieved by the development of a control electronic platform and the others prosthesis components, like actuators, sensors, mechanisms and the management program, that integrate all the components to actions of prosthesis. In this work was used only one finger to perform of all tests, and this finger is compatible with the development of a multifunction anthropomorphic prosthesis. The user command comes from myoelectric signal, but the actions in the prosthesis are executed unconsciously. The management program control the anthropomorphic movements based on defined trajectory and create information of force and temperature sensation to the user, proprioceptive feedback.
103

Proposta de um método de projeto de próteses de membros superiores com a utilização da engenharia e análise do valor. / Proposal of an upper limb prosthesis design method, which uses the value analysis and engineering.

Gustavo Longhi de Carvalho 18 February 2004 (has links)
As próteses de membros superiores atualmente disponíveis no mercado não atendem a muitos dos requisitos dos seus usuários, em especial devido à funcionalidade insuficiente e a seu alto peso e custo. Este fato, aliado à importância do assunto, foi a motivação deste trabalho, que utiliza a Análise do Valor no projeto deste tipo de próteses. Para isto, propõe uma metodologia de projeto, que utiliza a mencionada Análise, e aplica a mesma às próteses de membros superiores com o objetivo de obter configurações das mesmas que contenham vantagens comparando-se com as disponíveis atualmente. A Análise do Valor trabalha com funções, e por isto, as próteses, neste trabalho, foram vistas através das funções que deveriam executar. Para a obtenção destas funções e das suas especificações, foram consultados usuários de próteses, de quem as opiniões foram consideradas as mais importantes. Após estas consultas, foi executado um brainstorming com voluntários para a obtenção de idéias de novos componentes e novos tipos de próteses. A partir do resultado das entrevistas com usuários e do brainstorming, e com base nas pesquisas realizadas, foram propostas novas configurações de próteses que procurassem atender ao máximo possível das especificações que tinham sido obtidas. Em suma, esta dissertação pretende fornecer mais subsídios para se entender o que é necessário para que as próteses de membros superiores tenham uma aceitação maior e auxiliem mais seus usuários. A metodologia proposta, por sua vez, mostrou que tem potencial para ser útil na obtenção de produtos cada vez melhores, visto que ela pode ser aplicada a produtos em geral, não somente às próteses. / The available upper limb prosthesis in the market at this moment don’t correspond to many of the users’ requirements, mainly because of the insufficient functionality and the high weight and cost. This fact, allied to the importance of the subject, was the motivation of this work, which uses the Value Analysis in this kind of prosthesis design. For this purpose, it proposes a design method, which uses the mentioned Analysis, and applies it to the upper limb prosthesis aiming to obtain this product configurations with advantages, comparing to the available prosthesis at this moment. The Value Analysis works with functions, and, because of that, the prosthesis, in this work, were seen through the functions they should execute. To obtain these functions and its specifications, prosthesis users were consulted – their opinions were considered the most important. After these consultations, it was executed a brainstorming with volunteers to obtain new prosthesis’ kinds and components ideas. With the interviews and brainstorming results, and supported by the research made, they were proposed new prosthesis configurations, which had the goal to correspond to the maximum possible of the obtained specifications. In short, this dissertation intend to provide more subsidies to comprehend what is necessary to the upper limb prosthesis to have a bigger acceptance and help more its users. The proposed design method, at its side, showed that has potential to be useful in the more and more better products obtaining, because it can be applied to the products in general, not only to the prosthesis.
104

Parametrização dimensional, por modelo de regressão, de próteses de mão para crianças, confeccionadas por manufatura aditiva / Dimensional parameterization, by regression model, of hand prostheses for children, made by additive manufacture

Maia, Bruno Alves 24 August 2016 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2017-02-16T16:21:52Z No. of bitstreams: 2 Dissertação - Bruno Alves Maia - 2016.pdf: 9862769 bytes, checksum: da6934df826a53e405a0f542815fc54d (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Erika Demachki (erikademachki@gmail.com) on 2017-02-17T16:53:04Z (GMT) No. of bitstreams: 2 Dissertação - Bruno Alves Maia - 2016.pdf: 9862769 bytes, checksum: da6934df826a53e405a0f542815fc54d (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-02-17T16:53:04Z (GMT). No. of bitstreams: 2 Dissertação - Bruno Alves Maia - 2016.pdf: 9862769 bytes, checksum: da6934df826a53e405a0f542815fc54d (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-08-24 / The use of artificial limbs provides great improvements in the quality of life of people who were born with malformation or have lost their upper limbs. However, the value of conventional prostheses is not accessible to the majority of the population. In order to change this reality, began to emerge projects using additive manufacturing. The use of such technology allows the manufacture of more accessible and customized prostheses. However, the adequacy of project design is still a problem, due to the lack of data on the size of the upper limbs, especially on children and adolescents. Based on this need, this work seeks to find a way to parameterize the hand dimensions, thus helping in the better dimensioning of the prostheses. Thus, this work looks for a variable that presents satisfactory correlation with the dimensions of the upper limb. After finding such a relationship, a table and a parametric model were created that can estimate the length of the hand from the height. / A utilização de membros artificiais proporciona grandes melhorias na qualidade de vida de pessoas que nasceram com malformação ou perderam os membros superiores. No entanto, o valor das próteses convencionais não é acessível à maioria da população. Com o objetivo de modificar essa realidade, começaram a surgir projetos utilizando a manufatura aditiva. O emprego de tal tecnologia, permite a confecção de próteses mais acessíveis e customizadas. Porém, o dimensionamento adequado dos projetos ainda é um problema, devido à falta de dados relativos ao tamanho dos membros superiores, principalmente sobre crianças e adolescentes. Com base nessa necessidade, este trabalho busca encontrar uma forma de parametrizar as dimensões da mão, auxiliando assim no melhor dimensionamento das próteses. Sendo assim, este trabalho procura uma variável que apresenta correlação satisfatória com as dimensões do membro superior. Após encontrar tal relação, foram criados uma tabela e um modelo paramétrico que conseguem estimar o comprimento da mão a partir da estatura.
105

Forced use on arm function after stroke : clinically rated and self-reported outcome and measurement during the sub-acute phase / ”Forced use” för armfunktion efter stroke : kliniskt bedömda och självrapporterade resultat samt mätmetoder i subakut fas

Hammer, Ann M. January 2010 (has links)
The overall aim was to evaluate the effectiveness of forced use on arm and hand recovery after stroke by applying a restraining sling on the non-affected arm and to investigate psychometric properties of selected upper limb measures. Papers I and II reported a randomised trial with 1- and 3-month follow-ups. Thirty patients 1 to 6 months after stroke were included and received regular training for 2 weeks of intervention. The forced-use group had in addition a restraining sling on the non-paretic arm. Outcome measures were the Fugl-Meyer Assessment, the Modified Ashworth scale, the 16-hole peg test, grip force, the Action Research Arm test, and the Motor Assessment Scale (Paper I), and the Motor Activity Log (MAL) (Paper II). Results in Papers I and II showed no statistical difference in change between groups. Both groups improved over time. Paper III assessed the responsiveness of the MAL and its cross-sectional and longitudinal validity. The MAL was responsive to change, with Standardised Response Means and Responsiveness Ratios larger than 1.0. Correlations between the MAL and the other measures were mostly close to 0.50. Paper IV investigated test–retest intra-rater reliability of measuring grip force with Grippit, and assessed relationships between grip forces of both hands, and between sustained and peak grip force. The paretic hand needs to score a change of 10% or 50 N to exceed the measurement error. The mean ratio between sides was 0.66, and between sustained and peak grip force, 0.80–0.84. In conclusion, this thesis provides preliminary evidence that forced use does not generate greater improvement on upper limb motor impairment, capacity, and performance of activity than regular rehabilitation. The findings indicate that the MAL is a responsive measure of daily hand use in patients with stroke. Correlations of construct validity indicated that daily hand use might need to be measured separately from body function and activity capacity. The coefficients calculated for repeatability and reproducibility were acceptable, and the Grippit instrument can be recommended.
106

Déficits moteur et de coordination du membre supérieur hémiplégique : diagnostic et rééducation par l’isocinétisme / Motor and coordination deficits of hemiplegic upper limb : diagnosis and rehabilitation by the isokinetic

Hammami, Nadhir 13 November 2013 (has links)
La restauration fonctionnelle du membre supérieur chez l'hémiplégique séquellaire reste toujours l'objectif primordial recherché durant le processus de réhabilitation. De nos jours, les techniques émergentes de rééducation montrent de plus en plus d'efficacité et de réalisme, si elles sont accompagnées par les techniques conventionnelles et classiques. De plus, quelques idées anciennes ont évoluées vers l'utilisation du renforcement musculaire du membre atteint afin d'améliorer sa fonction motrice. En effet, le renforcement musculaire isocinétique constitue une technique potentiellement intéressante de rééducation pour des hémiplégiques. Dans le cadre de notre travail doctoral, nous avons utilisé le concept isocinétique pour réhabiliter les déficits moteurs et diagnostiquer les déficits de coordination du membre supérieur hémiplégique. En premier lieu, nous avons essayé de montrer le rôle de l'isocinétisme pour optimiser la prise en charge du membre supérieur chez l'hémiplégique. Nous avons d'abord présenté une revue de littérature sur le renforcement musculaire isocinétique après hémiplégie suite à une lésion cérébrale. Ensuite, nous avons évalué la faisabilité d'un programme basé sur ce type de renforcement, pour le coude et le poignet chez des hémiparétiques. Ainsi, l'utilité et l'efficacité de ce type de réentraînement isocinétique ont pu être mises en évidence. En second lieu, nous avons utilisé l'isocinétisme pour comprendre l'implication du rôle des afférences dans le déficit de coordination bimanuelle après accident vasculaire cérébral causant une hémiplégie. Dans l'ensemble, ces différents résultats autorisent à recommander l'outil isocinétique pour quantifier les déficits moteur et de coordination du membre supérieur chez l'hémiplégique, en vue d'une meilleure élaboration et mise en place de protocoles de rééducation isocinétique. / Functional restoration of the upper limb in sequelae hemiplegic remains the primary objective during the rehabilitation process. Nowadays, emerging rehabilitation techniques show more efficiency and realism, if they are accompanied by conventional and standard techniques. In addition, some old ideas have evolved to use the affected limb muscle strengthening to improve motor function. Indeed, the isokinetic muscle strengthening is a potentially interesting technique for rehabilitation of hemiplegic patients. As part of our doctoral work, we used the isokinetic concept to rehabilitate motor deficits and diagnose coordination deficits for hemiplegic upper limb. First, we tried to show the role of isokinetic to optimize the management of upper limb in hemiplegic patients. We firstly presented a review of literature on isokinetic muscle strengthening after hemiplegia following a brain injury. Then, we evaluated the feasibility of a training program based on this type of reinforcement for the elbow and wrist in the hemiparetic patients. Thus, the usefulness and effectiveness of this type of isokinetic exercise training have been highlighted. Second, we used the isokinetic to understand the contribution of afference-based processes to the impairment of bimanual coordination after stroke causing hemiplegia. On the whole, these results allow recommending the isokinetic tool to quantify motor and coordination deficits of upper limb in hemiplegic patients, for better development and implementation of isokinetic rehabilitation protocols.
107

Direkcionální asymetrie aktivity svalů horní končetiny a zad při nátahu luku; implikace pro bioarcheologii / Directional asymmetry of upper limb and back muscle activity during bow draw; implications for bioarcheology

Véle, Dominik January 2020 (has links)
This theses explores muscle activity during bow draw. The goal of his study is to evaluate whether muscle activity corresponds with increase in mechanical robusticity of the left humerus found in mezolithic osteological material. Muscle activity is measured by the means of surface electromyography. We measure activity of arm and back muscles. Activity was measured on m. deltoideus, m. infraspinatus, m. biceps brachii, m. triceps brachii and m. latissimus dorsi. Muscle activity was measured on 20 male archers, during bow draw of three wooden long-bows. Results of this study support the idea that change in robusticity of the left humerus could be caused by frequent bow use in post-glacial Europe.
108

The feasibility of action observation combined with repetitive task practice on upper limb outcomes in moderately impaired chronic stroke survivors

Griffin, Christine Elisabeth January 2020 (has links)
No description available.
109

Grasped Object Detection for Adaptive Control of a Prosthetic Hand

Andrecioli, Ricardo 06 June 2013 (has links)
No description available.
110

Distribution of Essential Tremor in the Degrees of Freedom of the Upper Limb

Pigg, Adam Charles 01 September 2017 (has links)
This study seeks to understand upper limb tremor in subjects with essential tremor (ET). A thorough understanding of tremor distribution will allow for the more effective development of tremor suppression devices, which offer an alternative to current treatments. Previous studies primarily focused on tremor in the hand only. This study seeks to characterize the distribution of tremor throughout the upper limb.We measured tremor in 25 subjects diagnosed with ET using motion capture, which provided displacement information of the limb during multiple postural and kinetic tasks. Inverse kinematics allowed us to analyze the motion capture data in the 7 major degrees of freedom (DOF) of the upper limb. The power spectral density estimate was used to determine: relative tremor magnitude throughout the DOFs, tremor variation between tasks, variation between subjects, and frequency variations between DOFs. Data analysis revealed that tremor increase is roughly proximal to distal. We also show that tremor magnitude in kinetic tasks is significantly higher than in postural tasks. Although we found some variation in tremor distribution between subjects, the roughly proximal to distal increase in tremor severity holds for several subsets of the study population. Finally, we found that tremor frequency doesnt vary significantly (< 1 Hz) between DOFs, in subjects with severe tremor. Our study shows that tremor distribution is quite stereotyped between subjects with ET. Furthermore, we have shown that tremor is greatest in the distal DOFs. This provides a compelling starting point for the development of future tremor suppression devices.

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