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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.
71

Modelling and control of an electric wheelchair virtual reality platform.

Motaung, Mokete Isaac. January 2014 (has links)
M. Tech. Electrical Engineering. / Discusses how to develop the kinematic and dynamic model and the controller for the 2-DOf motion platform used in an augmented reality environment for wheelchair driving. This comes as a motivation to help to train disabled and elderly people to drive wheelchairs.. With accurate inverse dynamic model, it is possible to achieve high performance control algorithms of robots and direct dynamic model is required for their simulation. The other part of this research was to model and control the roller for the feedback of the wheelchair wheels.
72

Design of a lower extremity mechatronic system to assist physically impaired individuals achieve a standing position.

Gregory, Unéné N. January 2014 (has links)
M. Tech. Electrical Engineering. / The hypothesis states that a closed loop control system could be applied to a mechatronic system consisting of a mechanical device(s) to be fitted onto the user, and other relevant periphery mechanical devices, appropriately actuated to provide powered movement to assist the wheelchair-bound individual securely attain a standing position.The premise upon which the hypothesis was to be tested relates to the control system's ability to facilitate the upward movement proposed and its degree of stability when simulating the system, thus re-creating the anticipated functionality.
73

Visual intention detection algorithm for wheelchair motion.

Luhandjula, Thierry Kalonda. January 2012 (has links)
D. Tech. Electrical Engineering. / Proposes a vision-based solution for intention recognition of a person from the motions of the head and the hand This solution is intended to be applied in the context of wheelchair bound individuals whose intentions of interest are the wheelchairs direction and speed variation indicated by a rotation and a vertical motion respectively. Both head-based and hand-based solutions are proposed as an alternative to solutions using joysticks pneumatic switches, etc.
74

Dynamic Stability Control of Front Wheel Drive Wheelchairs Using Solid State Accelerometers and Gyroscopes

Wolm, Patrick January 2009 (has links)
While the active dynamic stability of automobiles has increased over the past 17 years there have been very few similar advances made with electrically powered wheelchairs. This lack of improvement has led to a long standing acceptance of less-than-optimal stability and control of these wheelchairs. Accidents due to loss of stability are well documented. Hence, the healthcare industry has made several efforts for improved control of electric powered wheelchairs (EPWs) to provide enhanced comfort, safety and manoeuvrability at a lower cost. In response, an area of stability control was identified that could benefit from a feedback control system using solid state sensors. To design an effective closed–loop feedback controller with optimal performance to overcome instabilities, an accurate model of wheelchair dynamics needed to be created. Such a model can be employed to test various controllers quickly and repeatedly, without the difficulties of physically setting a wheelchair up for each test. This task was one central goal of this research. A wireless test-bed of a front wheel drive (FWD) wheelchair was also developed to validate a dynamic wheelchair model. It integrates sensors, a data control system, an embedded controller, and the motorised mechanical system. The wireless communication ensures the integrity of sensor data collected and control signals sent. The test-bed developed not only facilitates the development of feedback controllers of motorised wheelchairs, but the collected data can also be used to confirm theories of causes of dynamic instabilities. The prototype test-bed performed the required tasks to satisfaction as defined by the sponsor. Data collected from live tests in which the test-bed followed set patterns, was processed and analysed. The patterns were designed to induce instability. The analysis revealed that an occupied wheelchair is more stable than an unoccupied wheelchair, disproving an initial instability theory proposed in this research. However, a proximal theory explaining over-steer is confirmed. Two models of the FWD test-bed were created. First, a dynamic model inherited from prior research, based on equations of motion was tested and enhanced based on measured data. However, even with alterations to correct parameter values and variables in the equations, a complete model validation was not possible. Second, a kinematic model was created with a factor to compensate for dynamics not normally accounted in kinematic models. The kinematic model was partially validated versus the measured data. Although, still highly accurate, there is room for improvement in this model. Both models contained a sub-system drive motor model, to account for input forces to the FWD wheelchair system model, which is fully validated.
75

Successful use of early powered mobility : the experiences of the family /

Warwick, Tara Renee. January 2005 (has links) (PDF)
Thesis--University of Oklahoma. / Bibliography: leaves 97-100.
76

Uma contribui??o cr?tica para o redesenho de cadeiras de rodas adaptadas para crian?as e adolescentes com paralisia cerebral

Amorim, Brunna Michelle Paiva de 03 February 2009 (has links)
Made available in DSpace on 2014-12-17T14:52:43Z (GMT). No. of bitstreams: 1 BrunaMPA_capa_ate_pag_120.pdf: 3506558 bytes, checksum: d539a7d405b18bb07c4d7ce4689821cb (MD5) Previous issue date: 2009-02-03 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work was aimed at making a critical analysis of the product wheelchair, both for using four different models, which were objects of study of the dissertation of Cl?udia Regina Cabral Galv?o, entitled Critical Analysis of the Mobility Products Seated a wheelchair - Used by Children and Adolescents with Cerebral Palsy in Natal / RN and other municipalities of Rio Grande do Norte . This product is considered an instrument in the social rehabilitation of great importance for people with physical disabilities. This study aims to position the issue and develop comments on technical up grading of certain models according to the needs of the user. Describes features of four models in search searched through catalogs in order to know its advantages and disadvantages of use. Were presented the definitions of ergonomics and ergonomic aspects to be considered on a design, the study of anthropometry and its recommendations. Discussions the methodology of project design in two parts: the first, on the structuring of design problem (formulation, analysis, synthesis and evaluation.) And the second on the project (design and development, implementation and evaluation and solution). With that review will include the possibilities for a new redesign of the wheelchair, based on forms of adaptation in order to achieve the target that was compressed by the average population studied. Seeks to that this project makes an improvement in quality of life of people in wheelchairs by including these people in society but also the improvement of rehabilitation / Esse trabalho teve por objetivo a realiza??o de uma an?lise cr?tica do produto cadeira de rodas, utilizando para tanto quatro modelos diferentes, que foram objetos de estudo da disserta??o de Cl?udia Regina Cabral Galv?o, intitulada An?lise Cr?tica dos Produtos de Mobilidade Sentada- Cadeiras de Rodas Utilizadas por Crian?as e Adolescentes com Paralisia Cerebral em Natal/RN e outros Munic?pios do Rio Grande do Norte . Este produto ? considerado na reabilita??o social um instrumento de grande relev?ncia para as pessoas com defici?ncia f?sica. Este estudo visa posicionar a quest?o e desenvolver observa??es sobre t?cnicas de readapta??o de determinados modelos de acordo com a necessidade do usu?rio. Descreve caracter?sticas dos quatro modelos pesquisados atrav?s de busca em cat?logos, com intuito de conhecer suas vantagens e desvantagens de uso. Foram apresentados alguns aspectos ergon?micos que devem ser considerados em um projeto, o estudo da antropometria e suas recomenda??es. Aborda a metodologia de projeto organizada em duas partes: a primeira, intitulada de estrutura??o de problema projetual (formula??o, an?lise, s?ntese e avalia??o); e a segunda intitulada de projeto (concep??o e desenvolvimento, avalia??o e solu??o e execu??o). Com isso analisam quais ser?o as possibilidades para um novo redesenho de cadeira de rodas, baseado nas formas de adapta??o, de modo a atingir os pesquisados com faixa et?ria entre 5 -12 anos, correspondente ? 63,7% dos pesquisados. Pretende-se que este projeto viabilize uma melhoria na qualidade de vida dos cadeirantes atrav?s do aumento da inclus?o destas pessoas na sociedade
77

Not just the right for a wheelchair but the right wheelchair : a multi-site study of the wheelchair public service provision in Belo Horizonte city, Brazil

Maximo, Tulio P. dos Santos January 2018 (has links)
For decades the care of disabled population in Brazil has been neglected by the government and was provided largely by the charitable institutions. It was as only recently, as in the year 2011 that Brazilian government created the national plan for the rights of the disabled people. The plan articulates policies regarding social inclusion, access to education, accessibility and health care. The last section of the plan includes the provision of wheelchairs free of cost to the Brazilians citizens, who are in need of a wheelchair. It is common knowledge that a wrong wheelchair specification can lead to physical damage for the user and the carer; the abandonment of device, and wastage of time and resources involved in the wheelchair provision. The World Health Organization has propounded several good practices and training material with reference to wheelchair services towards enabling of right wheelchair fit to the user characteristics. Though, there is no evidence that the service provided in Brazil adheres to these guidelines or any other wheelchair service good practice. This research reviews the wheelchair service provision in Belo Horizonte city, Brazil with the aim to understand the functionality of these services in order to provide context-specific interventions and recommendations to improve the design of current services. Herein, three main studies were conducted using a mix of methods: A first exploratory study was conducted to assess the Belo Horizonte assistive technology services and identify a research focus. A second study was conducted to develop an in-depth insight on the understanding of the wheelchair service provided and to collect the necessary information towards creating a context-based and collaborative designed intervention. A third study was conducted to evaluate and improve the proposed interventions. A total of sixty-six interviews were conducted (n=66) with service stakeholders and two hundred and fifty user care observed (n=250) from which ninety-five (n=95) tested the proposed interventions.
78

Etické zásady profesionálního přístupu pomáhajících pracovníků k lidem s tělesným postižením na vozíku / Ethical Principles of Helpers´Professional Approach to Disabled People in Wheelchairs

HANTOVÁ, Jitka January 2013 (has links)
The thesis aims to identify the most important ethical principles that should be part of the professional approach of helping professionals towards disabled people in wheelchairs, however, their application involves members of the majority society, too. The thesis then refers to the conditions that support application of these principles in helping professionals and the historical development of the care of disabled people in wheelchairs. The thesis includes an important part that presents a conducted research dealing with these principles from the view of disabled people in wheelchairs and helping professionals themselves. Thus the main aim of the research is to compare the two perspectives.
79

Evidências de validade da avaliação aeróbia em quadra em jogadores de basquetebol em cadeiras de roda

Santos, Poliana Piovezana dos 17 December 2007 (has links)
Made available in DSpace on 2016-12-06T17:07:15Z (GMT). No. of bitstreams: 1 Poliana P dos Santos.pdf: 894535 bytes, checksum: f0f6418cf1c97dffa01164840dd75cb9 (MD5) Previous issue date: 2007-12-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The objective of this study was to analyse: a) the heart rate (HR) and lactate concentrations responses in incremental Field test (indoor) in male wheelchair basketball players (WBP) and b) the relation between the HR and [La] thresholds with variables measured in official matches. Ten WBP (30,5 ± 7,9 years) performed the test proposed per Léger and suitable Lambert of Vinet et al. (2002). The lactate threshold 1 and 2 (LT1 and LT2) and three distinct techniques of identification of the heart rate deflection point (HRDP), visual and mathematics model were determined. Moreover, the athletes had been monitored during matches, to determinate the participation on 3 physiological domain, delimited by the LT1 and LT2. The TLLA performaned couldbe considered of maximal cardiovascular and metabolic effort (HRpeak= 175 ± 12 bpm and [La]peak = 9,1 ± 2,2 mmol.l-1), the HRDP can be a generalized physiological variable, although it can overestimate and not to be associates to the LT2. A similar distribution of the %T effort performed by (WBP) during official matches seems to occur for the moderate, intense and severe domain. No significant relationship between TLLA and matches variables were found. / O objetivo deste estudo foi analisar: a) comportamento da freqüência cardíaca (FC) e das concentrações de lactato ([La]) no sangue em teste progressivo de quadra em basquetebolistas em cadeiras de roda (BCR) e b) a relação entre Limiares de Transição da FC e [La] com variáveis obtidas em partidas oficiais. Dez BCR (30,5 ± 7,9 anos), do sexo masculino, foram submetidos ao teste de Léger e Lambert adaptado de Vinet et al. (2002) (TLLA). Foram determinados os limiares de lactato 1 e 2 (LL1 e LL2) e três técnicas distintas de identificação do Ponto de Deflexão da FC (PDFC), visual e matemática. Além disso, os atletas foram monitorados durante partidas, sendo determinada a participação em cada domínio fisiológico, delimitados pelos dois LL. O TLLA pode ser considerado de esforço cardiovascular e metabólico máx (FCpico = 175 ± 12 bpm e [La]pico = 9,1 ± 2,2 mmol.l-1), os PDFC são fisiologicamente generalizáveis, apesar de superestimarem e não serem associados à LL2. Existe uma distribuição similar do esforço em BCR nos domínios moderado, intenso e severo, sendo que ariáveis do TLLA apresentam baixas correlações com variáveis do jogo. Em geral, os parâmetros fisiológicos e seus respectivos índices testados devem ser vistos com cautela para a avaliação aeróbia destes atletas, sendo PDFC um método promissor para ser empregado neste tipo de avaliação.
80

Projeto conceitual e protótipo de uma cadeira de rodas servo-assistida / Conceptual project and prototype of a servo-assisted wheelchair

Fausto Orsi Medola 27 May 2013 (has links)
Este trabalho propõe um novo conceito de cadeira de rodas manual ergonômica com assistência motorizada servo controlada. A mobilidade em cadeira propulsionada manualmente é uma das formas mais utilizadas de locomoção entre pessoas com deficiências, porém expõe o usuário ao risco de lesão nos membros superiores e não propicia independência em todas as situações de locomoção diária. A primeira alternativa tecnológica aplicada pelo homem foi a motorização. No entanto, o uso desta não implica em melhora da mobilidade, pois leva o usuário ao sedentarismo. Neste sentido, fazendo a integração do histórico, ergonomia, biomecânica e engenharia mecatrônica, este projeto tem como objetivo o desenvolvimento do projeto conceitual ao protótipo - de uma cadeira de rodas manual com assistência motorizada complementar e proporcional à força propulsora aplicada pelo usuário. O delineamento do projeto envolveu o levantamento das evidências científicas relacionadas aos aspectos da configuração de cadeiras manuais determinantes para a melhoria do desempenho na mobilidade e conforto. A criação do conceito envolveu ainda a realização de estudos complementares dos aspectos mecânicos, ergonômicos e cinemáticos da locomoção em cadeiras manuais. O conceito do protótipo tem seus pilares na: propulsão, através de um servo-motor centralizado que atua nas duas rodas traseiras através de um diferencial mecânico, simplificando o controle da assistência motorizada; no projeto do aro propulsor ortogonal com acoplamento assimétrico com a roda em cambagem, proporcionando melhor acesso das mãos ao aro; projeto do aro propulsor, baseado em aspectos dactilo-anatômicos; projeto e configuração da cadeira, estruturada nas evoluções tecnológicas das cadeiras manuais e adaptada às características antropométricas da população brasileira; assistência motorizada controlada por um sistema de avaliação contínua da inclinação do terreno, forças aplicadas ao aro e o deslocamento angular das rodas medidos por acelerômetro, células de carga e encoder ótico, respectivamente. A efetivação do presente conceito favorece a mobilidade independente do cadeirante, podendo reduzir o custo referente ao uso prolongado de cadeiras manuais: lesão dos membros superiores e incapacidade funcional. Aprimorar a mobilidade de usuários de cadeira de rodas favorece sua independência e participação social, aspectos essenciais para a melhora da qualidade de vida. / This study proposes a new concept of ergonomic manual wheelchair with servo-controlled motor assistance. The mobility in manually propelled wheelchairs is one of the most used means of locomotion among people with disabilities, but it exposes the users to the risk of upper limb injuries and does not provide independence in all the situations of daily locomotion. The first solution applied was the use of a electric-powered motors. However, its usage does not lead to an improvement in mobility and imposes the sedentary condition to the users. Thus, by integrating of the equipment history, ergonomics, biomechanics and mechatronics engineering, this project aims to develop - from the conceptual design to the prototype - a manual wheelchair with complementary motorized assistance that is proportional to the pushing force applied by the user. The project design involved the search for scientific evidences related to the aspects of the wheelchair configuration determinants for the improvement on mobility performance and comfort. The concept creation also involved complementary studies of the mechanics, ergonomics and kinematics of manual wheelchair mobility. The fundamentals of the equipment conception are: propulsion by a servo-motor centrally located that operates the rear wheels by differential transmission. thus simplifying the motor assistance control; the design of an orthogonal handrim coupled to the a cambered wheel, that provides better access of the hands to the rim; the dactyl-anatomical design of the handrim; the wheelchair configuration designed based on the technological evolution of the manual wheelchairs and anthropometric features of the Brazilian population; motor assistance controlled by a system with real-time assessment of the ground slope, handrim forces and angular displacement of the wheels measured, respectively, by accelerometer, load cells and optical encoder. This concept favors the independent mobility of the users and may reduce the cost related to the long term use of manual wheelchairs: upper limb injuries and functional impairment. Improving the mobility of wheelchair users favors their independence and social participation, two essential aspects for the improvement in quality of life.

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