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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.
31

GENTLE/A : adaptive robotic assistance for upper-limb rehabilitation

Gudipati, Radhika January 2014 (has links)
Advanced devices that can assist the therapists to offer rehabilitation are in high demand with the growing rehabilitation needs. The primary requirement from such rehabilitative devices is to reduce the therapist monitoring time. If the training device can autonomously adapt to the performance of the user, it can make the rehabilitation partly self-manageable. Therefore the main goal of our research is to investigate how to make a rehabilitation system more adaptable. The strategy we followed to augment the adaptability of the GENTLE/A robotic system was to (i) identify the parameters that inform about the contribution of the user/robot during a human-robot interaction session and (ii) use these parameters as performance indicators to adapt the system. Three main studies were conducted with healthy participants during the course of this PhD. The first study identified that the difference between the position coordinates recorded by the robot and the reference trajectory position coordinates indicated the leading/lagging status of the user with respect to the robot. Using the leadlag model we proposed two strategies to enhance the adaptability of the system. The first adaptability strategy tuned the performance time to suit the user’s requirements (second study). The second adaptability strategy tuned the task difficulty level based on the user’s leading or lagging status (third study). In summary the research undertaken during this PhD successfully enhanced the adaptability of the GENTLE/A system. The adaptability strategies evaluated were designed to suit various stages of recovery. Apart from potential use for remote assessment of patients, the work presented in this thesis is applicable in many areas of human-robot interaction research where a robot and human are involved in physical interaction.
32

Prediction of muscle activity during loaded movements of the upper limb

Tibold, R., Fuglevand, A. J. January 2015 (has links)
BACKGROUND: Accurate prediction of electromyographic (EMG) signals associated with a variety of motor behaviors could, in theory, serve as activity templates needed to evoke movements in paralyzed individuals using functional electrical stimulation. Such predictions should encompass complex multi-joint movements and include interactions with objects in the environment. METHODS: Here we tested the ability of different artificial neural networks (ANNs) to predict EMG activities of 12 arm muscles while human subjects made free movements of the arm or grasped and moved objects of different weights and dimensions. Inputs to the trained ANNs included hand position, hand orientation, and thumb grip force. RESULTS: The ability of ANNs to predict EMG was equally as good for tasks involving interactions with external loads as for unloaded movements. The ANN that yielded the best predictions was a feed-forward network consisting of a single hidden layer of 30 neural elements. For this network, the average coefficient of determination (R2 value) between predicted and actual EMG signals across all nine subjects and 12 muscles during movements that involved episodes of moving objects was 0.43. CONCLUSION: This reasonable accuracy suggests that ANNs could be used to provide an initial estimate of the complex patterns of muscle stimulation needed to produce a wide array of movements, including those involving object interaction, in paralyzed individuals.
33

Increasing the robustness of active upper limb prostheses

Stango, Antonietta 23 November 2016 (has links)
No description available.
34

Functional Integration of the Hominin Forelimb

Macias, Marisa Elena January 2015 (has links)
<p>During the last six million years, humans shifted from a primarily arboreal lifestyle to a habitually bipedal, terrestrial lifestyle. Australopithecus had a significant bipedal component to its locomotion; whether suspensory and climbing behavior were also important has remained unclear. Morphological features of the forelimb have been linked to locomotor differences among primates, but the interpretation of human fossils has remained problematic.</p><p>This dissertation examined the total morphological pattern of the forelimb, specifically the functional integration of the musculature and joint systems. This approach employed both geometric morphometrics and a biomechanical modeling approach to studying how and how well the forelimb morphology of living suspensory and quadrupedal primates, as well as humans and fossil hominins, accommodate climbing and suspensory locomotion. Data collected with a microscribe 3-D digitizer on the scapula, humerus, radius, and ulna of Australopithecus sediba, Australopithecus afarensis, and Homo erectus were compared to a sample of Homo sapiens, Pan troglodytes, Pan paniscus, Gorilla gorilla, Pongo pygmaeus, Hylobates lar, and Macaca fuscicularis.</p><p>The hominin upper limb is a rich mosaic of primitive and derived traits. The blade of Australopithecus sediba, although appearing most similar to extant orangutans, is in fact functionally most similar to chimpanzees. The overall morphology of the australopith elbow joint appears most similar to Pan, as does the elbow joint of Homo erectus, suggesting that the modern human configuration happened more recently than 1.5 million years ago. </p><p>Au. afarensis and Au. sediba share important similarities, but are clearly distinct species. While their overall elbow joint shape is strikingly similar, the articular surface is not identical. Au. afarensis is more similar in this respect to Pan and Homo, while Au. sediba is more similar to extant taxa that spend substantially more time engaging in vertical climbing and suspensory behavior.</p><p>The results from this study support previous interpretations that not all australopiths across time were employing the same locomotor repertoire. While this study does not present unambiguous conclusions regarding early hominin arboreal locomotion, this study suggests that the morphology of the upper limb is varied, and caution must be taken when interpreting single skeletal elements in the hominin fossil record.</p> / Dissertation
35

Asymétrie et courbures de la clavicule chez l'humain et les grands singes

Richer, Claude January 2008 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.
36

Terapia de uso forçado modificada não altera função motora do membro superior não parético / Modified forced used therapy does not change motor function on the non-paretic upper limb

Santos, Tamyris Padovani dos 02 March 2015 (has links)
A Terapia de Uso Forçado (TUF) e uma técnica se propõe a reverter o desuso aprendido e assim conduzir a plasticidade encefálica pós-AVE. Por se tratar de uma terapia restritiva, que força a utilização de um dos membros superiores e detrimento do outro essa modalidade terapêutica é passível de críticas. Sendo assim, o nosso trabalho foi estruturado para investigar se existem prejuízos no MS não acometido e ainda se propõe a analisar de maneira instrumentalizada os benefícios produzidos no MS parético. Participaram deste estudo 32 indivíduos que sofreram AVE isquêmico e que apresentavam hemiparesia. Os indivíduos foram randomizados em dois grupos de tratamento por quatro semanas consecutivas: TUF (imobilização do MS não acometido por 24 horas, durante 4 semanas) e FC (fisioterapia convencional, duas vezes por semana). A avaliação foi realizada antes do início, 2 semanas após, no final do protocolo e três meses após o término. Foram utilizadas as escalas: National Institute of Health Stroke Scale (NIHSS), Teste Motor de Wolf (WMFT), dinamometria (preensão palmar) e eletromiografia de superfície (músculos extensores do punho). Os dados do grupo TUF foram analisados por uma análise de variância de uma via e os dados da FC por um teste em t para amostras pareadas. Para a comparação intergrupos foi utilizado o teste t de Student. Foram consideradas diferenças significativas p 0,05. A análise das pontuações da NIHSS não revelou diferenças significativas na comparação intra e intergrupos. A análise dos dados da dinamometria intra e intergrupos do lado não parético, não revelou diferenças estatísticas. Para o lado parético os dados da TUF mostraram um aumento na % Kgf em relação aos dados iniciais para o lado parético (F: 2,90) e parético a direita (F:2,70). A análise dos dados de eletromiografia intra e intergrupo, do lado não parético não revelou diferenças estatísticas. Já para o lado parético, os dados da TUF mostraram um aumento de % RMS em relação aos dados iniciais para o lado parético (F:2,43) e parético a direita (F:1,67). Para os dados da WMFT, não observamos diferenças para o lado não parético no grupo TUF. Entretanto o para a FC, observamos uma diminuição do tempo de execução das atividades no lado não parético e a esquerda (t=3,26). Em relação ao lado parético, parético a direita e parético a esquerda, o grupo TUF apresentou modificações em todos as comparações (F:10,08), (F:4,24;) e (F:6,75), respectivamente. Já no grupo FC, somente para a comparação no lado parético (t=2,21). Ambos os grupos apresentam um melhor desempenho nas tarefas individuais no lado não parético. Entretanto, o grupo FC no lado não parético esquerdo apresenta uma redução do tempo na atividade cotovelo estendido em relação ao tempo final do grupo TUF (t=2,45). Em relação ao lado parético, o grupo TUF apresenta uma redução do tempo de atividade para um grande número de tarefas individuais, o que não acontece com o grupo FC. Ainda, o grupo TUF tem uma redução do tempo de execução significativa em relação ao grupo FC no lado parético, para as tarefas cotovelo estendido com peso (t=2,45) e girar chave na fechadura (t=2,67).Nosso trabalho mostra que a TUF melhora o desempenho motor do lado parético. Ainda, é segura uma vez que não observamos prejuízos motores do lado não parético. / The Forced Used Therapy (FUT) is a technique proposes to reverse learned nonuse and thus lead to brain plasticity after stroke. Because it is a restrictive therapy that forces the use of an upper limb in the detriment of another this therapeutic modality is subjected to criticism. Thus, our work was structured to investigate if there are impairments in not paretic UL and aims intends to analyze the possible benefits produced in paretic UL. The study included 32 subjects who experienced ischemic stroke and who had hemiparesis. Subjects were randomized in two treatment groups for four consecutive weeks: FUT (non-paretic UL immobilization for 24 hours to 4 weeks) and SP (standard physiotherapy twice a week). The evaluation was performed at baseline, 2 weeks after, at end of the protocol and three months follow up. We used the scales: National Institute of Health Stroke Scale (NIHSS), Wolf Motor Function Test (WMFT), dynamometer (handgrip) and surface electromyography (extensor muscles of the wrist). Data from the FUT group were analyzed by one way ANOVA and data the SP by a t-test for paired samples. For comparisons between groups, Student\'s t test was used. Significant values were considered by p 0.05. The analysis of the NIHSS scores revealed no significant differences in intragroup and intergroup comparison. Dynamometry data analysis of intra and inter group in the non-paretic side showed no statistical differences. For the paretic side, FUT data showed an increase in % Kgf relate to the initial to paretic side (F: 2.90) and paretic at the right (F: 2.70). Electromyography data analysis of intra- and intergroup, in the non-paretic side, showed no statistical differences. As for the paretic arm, the data showed an increase in % RMS of FUT compared to the initial for the paretic (F: 2.43) and right paretic (F: 1.67). For WMFT data, there were no differences for the non-paretic side in the FUT group. However, for the SP, we observed a reduction of the execution time of activities in the non-paretic side and paretic at the left (t = 3.26). In relation to the paretic, paretic, paretic to right and left, the FUT group showed changes in all comparisons (F: 10,08), (F: 4.24) and (F: 6.75), respectively. In the SP group, only for comparison in paretic (t = 2.21). Both groups perform better on individual tasks in the non-paretic side. However, the SP group in the left non-paretic side showed a reduction of time in the elbow extended activity in relation to the FUT final (t = 2.45). The FUT group for paretic side compared to the SP group has a less duration of activity for a large number of individual tasks, which does not happen with the SP group. Still, the FUT group has a significant reduction in execution time compared to the SP group in paretic hand for tasks elbow extended with weight (t = 2.45) and turn key in the lock (t = 2.67). Our work shows that the FUT improves motor performance of the paretic hand. Still, it is safe since no observed loss of the non-paretic arm.
37

Machine learning-based dexterous control of hand prostheses

Krasoulis, Agamemnon January 2018 (has links)
Upper-limb myoelectric prostheses are controlled by muscle activity information recorded on the skin surface using electromyography (EMG). Intuitive prosthetic control can be achieved by deploying statistical and machine learning (ML) tools to decipher the user's movement intent from EMG signals. This thesis proposes various means of advancing the capabilities of non-invasive, ML-based control of myoelectric hand prostheses. Two main directions are explored, namely classification-based hand grip selection and proportional finger position control using regression methods. Several practical aspects are considered with the aim of maximising the clinical impact of the proposed methodologies, which are evaluated with offline analyses as well as real-time experiments involving both able-bodied and transradial amputee participants. It has been generally accepted that the EMG signal may not always be a reliable source of control information for prostheses, mainly due to its stochastic and non-stationary properties. One particular issue associated with the use of surface EMG signals for upper-extremity myoelectric control is the limb position effect, which is related to the lack of decoding generalisation under novel arm postures. To address this challenge, it is proposed to make concurrent use of EMG sensors and inertial measurement units (IMUs). It is demonstrated this can lead to a significant improvement in both classification accuracy (CA) and real-time prosthetic control performance. Additionally, the relationship between surface EMG and inertial measurements is investigated and it is found that these modalities are partially related due to reflecting different manifestations of the same underlying phenomenon, that is, the muscular activity. In the field of upper-limb myoelectric control, the linear discriminant analysis (LDA) classifier has arguably been the most popular choice for movement intent decoding. This is mainly attributable to its ease of implementation, low computational requirements, and acceptable decoding performance. Nevertheless, this particular method makes a strong fundamental assumption, that is, data observations from different classes share a common covariance structure. Although this assumption may often be violated in practice, it has been found that the performance of the method is comparable to that of more sophisticated algorithms. In this thesis, it is proposed to remove this assumption by making use of general class-conditional Gaussian models and appropriate regularisation to avoid overfitting issues. By performing an exhaustive analysis on benchmark datasets, it is demonstrated that the proposed approach based on regularised discriminant analysis (RDA) can offer an impressive increase in decoding accuracy. By combining the use of RDA classification with a novel confidence-based rejection policy that intends to minimise the rate of unintended hand motions, it is shown that it is feasible to attain robust myoelectric grip control of a prosthetic hand by making use of a single pair of surface EMG-IMU sensors. Most present-day commercial prosthetic hands offer the mechanical abilities to support individual digit control; however, classification-based methods can only produce pre-defined grip patterns, a feature which results in prosthesis under-actuation. Although classification-based grip control can provide a great advantage over conventional strategies, it is far from being intuitive and natural to the user. A potential way of approaching the level of dexterity enjoyed by the human hand is via continuous and individual control of multiple joints. To this end, an exhaustive analysis is performed on the feasibility of reconstructing multidimensional hand joint angles from surface EMG signals. A supervised method based on the eigenvalue formulation of multiple linear regression (MLR) is then proposed to simultaneously reduce the dimensionality of input and output variables and its performance is compared to that of typically used unsupervised methods, which may produce suboptimal results in this context. An experimental paradigm is finally designed to evaluate the efficacy of the proposed finger position control scheme during real-time prosthesis use. This thesis provides insight into the capacity of deploying a range of computational methods for non-invasive myoelectric control. It contributes towards developing intuitive interfaces for dexterous control of multi-articulated prosthetic hands by transradial amputees.
38

Vliv posilovacího cvičení na Biokineticu do plaveckého výkonu na 50 m kraul / Effect of strengthening exercises on Biokinetic to swimming performance at 50 m crawl

Nezdara, Jaroslav January 2019 (has links)
Title: Effect of strengthening exercises on Biokinetic to swimming performance at 50 m crawl. Objectives: The aim of this work is to find out whether a two-month movement intervention performed on a swimming simulator (Biokinetic) will affect the swimming performance of a 50 m crawl by FTVS students. Methods: Five probands of the 2nd year of the follow-up study at Charles University FTVS participated in the research. The anthropometric data were obtained using the TANITA testing device. To determine the maximum endurance muscle strength of the upper limbs and other movement parameters, we used the Biokinetic device. In order to determine the maximum swimming performance, we carried out a swimming test for 50 m with the crawl technique. Interest activities were identified through a questionnaire. Data were analyzed by MS EXCEL and NCSS 2019. Results:The results show, that the Biokinetic weight training exercises had a positive influence on swimming performance at a distance of 50 m crawl in swimming pool. In the analysis of the technique of performing motion shots on Biokinetic, we found an increase in the frame frequency, but a decrease in the overall path. The increased in frequency according to our findings results in a reduction of the total path of the motion cycles. All probands experienced an...
39

Simulated Tremor Propagation in the Upper Limb: From Muscle Activity to Joint Displacement

Corie, Thomas Henry 01 April 2018 (has links)
Although tremor is the most common movement disorder, there are few non-invasive treatment options. One of the obstacles to creating effective tremor suppression devices is our lack of understanding regarding where tremor originates (which muscles), how it propagates through the limb (to which degrees of freedom, DOF), and where it manifests most severely (which DOF). To investigate these questions, we created a simple, linear time-invariant model to simulate tremor, with tremorogenic muscle activity input (in the 15 major superficial muscles from the shoulder to the wrist) and joint displacement output (in the 7 major upper limb DOF). The model included excitation-contraction dynamics, musculoskeletal geometry (muscle moment arms) and the mechanical impedance (inertia, damping, and stiffness) of the limb. From our simulation results, we determined four principles of tremor propagation. First, the distribution of tremor depends strongly on musculoskeletal dynamics. Second, the spreading of tremor is due to inertial coupling (primarily) and musculoskeletal geometry (secondarily). Third, tremor spreads narrowly in the sense that most of the tremor caused by a muscle occurs in a small number of DOF. Lastly, assuming uniform distribution of tremorogenic activity among upper-limb muscles, tremor increases proximal-distally, and the contribution from muscles increases proximal-distally.
40

Contribuições articulares do complexo do ombro e coluna cervical de crianças com paralisia obstétrica do plexo braquial durante tarefas de alcance / Joint contributions of the shoulder complex and cervical spine in children withobstetric brachial plexus palsy during reaching tasks

Medeiros, Daiane Lazzeri de 22 February 2019 (has links)
Objetivos: Comparar a função do membro superior e qualidade de vida (QOL) entre crianças com paralisia obstétrica do plexo braquial (POPB) e controles. Além disso, investigar os padrões de movimentos e coordenação intersegmentar de crianças com POPB e típicas durante tarefas de alcance em diferentes velocidades de execução. Métodos: Foram avaliadas crianças com POPB e típicas com idade entre 4 e 14 anos. A função do membro superior das crianças com POPB foi avaliada por meio da Modified Mallet Scale (MMS) e Active Movement Scale (AMS). A qualidade de vida dessa população foi avaliada por meio do Pediatric Outcome Data Collection Instrument (PODCI) e Child Health Questionnaire (CHQ). A avaliação cinemática tridimensional foi registrada pelo equipamento 3 SPACE Liberty (Polhemus. Inc, Colchester, VT) com taxa de aquisição de 120 Hz. A avaliação cinemática foi realizada no membro comprometido da criança com POPB e no membro dominante da criança típica durante as tarefas de alcance alto (tocar uma bola posicionada acima da cabeça), colocar a mão sobre o bolso traseiro da calça, colocar a mão na cabeça, elevação e abaixamento do braço no plano frontal. As três primeiras tarefas citadas acima, foram realizadas em duas condições, velocidade preferida e velocidade rápida. Foram analisadas as amplitudes de movimento do membro superior, escápula e cervical utilizadas durante as tarefas mão na bola, mão no bolso e mão na cabeça, e os movimentos da escápula durante a elevação e abaixamento do braço. Foi realizada a análise de codificação do vetor, do ângulo de acoplamento flexão do ombro-flexão da cabeça para a tarefa mão na cabeça, flexão do ombro-extensão de cotovelo para a tarefa mão na bola, e os ângulos de acoplamento dos movimentos da escápula-adução/abdução do ombro na elevação e abaixamento do braço no plano frontal. Resultados: As crianças com POPB apresentaram menores pontuações na maioria dos domínios avaliados por meio do PODCI e CHQ. As crianças com POPB tiveram menor função do membro superior avaliado por meio da MMS e AMS quando comparadas as crianças típicas. As crianças com POPB apresentaram diferentes padrões de movimento da escápula, ombro, cotovelo e cabeça comparados as crianças típicas nas tarefas de alcance. Na elevação e abaixamento do braço os movimentos da escápula forma similares entre os grupos, no entanto, a estratégia de coordenação da protração da escápula durante o abaixamento dobraço foi diferente. Além disso, a coordenação das crianças com POPB foi diferente na tarefa mão na bola quando comparado as crianças típicas, e apresentaram coordenação similar na tarefa mão na cabeça. Conclusão: A POPB influencia negativamente a qualidade de vida e a função do membro superior dessas crianças. As crianças com POPB e típicas utilizaram diferentes padrões de movimento da escápula, ombro, cotovelo e cabeça nas tarefas de alcance avaliadas. A coordenação das crianças com POPB foi diferente quando comparadas as típicas ao realizar movimento voltado ao ambiente externo como na tarefa mão na bola e apresentou coordenação semelhante quando o movimento foi realizado no próprio corpo (mão na cabeça). As crianças com POPB apresentam padrões de movimento escapular semelhantes para executar a elevação e abaixamento do braço no plano frontal, mas a estratégia de coordenação do movimento de protração da escápula durante o abaixamento do braço foi diferente entre os grupos / Objectives: To compare the upper limb function and quality of life (QOL) between children with neonatal brachial plexus palsy and unaffected controls. Moreover, we aimed to investigate the movement patterns and intersegmental coordination in NBPP children and matched controls during reaching tasks at different execution speeds. Methods: Children with NBPP and typical children aged 4 to 14 years were evaluated. The upper limb function was assessed using the Modified Mallet Scale (MMS) and Active Movement Scale (AMS). The quality of life was evaluated through the Pediatric Outcome Data Collection Instrument (PODCI) and the Child Health Questionnaire (CHQ). The three-dimensional kinematic evaluation was recorded by the 3 SPACE Liberty (Polhemus. Inc, Colchester, VT) with 120 Hz sampling frequency. Kinematic of the injured limb of NBPP children and the dominant limb of unaffected controls were recorded during a high-reach task (touch a ball), hand-toback-pocket task, hand-to-head task and elevation and lowering of the arm in the frontal plane. The first three tasks were performed in two conditions within two speeds, preferred speed and as fast as possible speed. We analyzed the range of motion of the upper limb, scapula and cervical during the reach tasks, and the scapula movements during the arm elevation and lowering. We also performed the vector coding analysis of the shoulder flexion - head flexion coupling angle in the hand to head task, shoulder flexion - elbow extension coupling angle during high reach task, and the coupling angle of scapula movements - shoulder abduction/aduction in the elevation and lowering of the arm. Results: Children with NBPP presented lower scores for most of the QOL domains evaluated through PODCI and CHQ. The NBPP children has lower limb upper arm function compared to the unaffected controls evaluated through MMS and AMS. The NBPP children and controls used different scapulothoracic, shoulder, elbow and head kinematic movement patterns in the reach tasks. In the arm elevation and lowering the scapula movement were similar between the groups, however, the coordination strategy of scapula protraction during the arm lowering was different. Furthermore, the coordination of NBPP children was different compared to unaffected controls in the hand on ball task, and presented similar coordination in the hand to head task. Conclusions: The NBPP has a negative influence on the quality of life and upper limb funcion of these children. The NBPP children and controls used differentscapulothoracic, shoulder, elbow and head kinematic movement patterns in the reach tasks. The coordination of NBPP children was different compared to unaffected controls when performing arm movements in the external environment (hand on ball task), and presented similar coordination when movements were made to their own body, as in the hand to head task. The NBPP children present similar scapular movement patterns to execute the arm elevation and lowering in the frontal plane, but the coordination strategy of scapula protraction movement during the lowering arm was different between the groups

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