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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

Design and Evaluation of a Knee-Extension-Assist

Spring, Alexander January 2011 (has links)
Quadriceps muscle weakness is a condition that can result from a wide variety of causes, from diseases like polio and multiple sclerosis to injuries of the head and spine. Individuals with weakened quadriceps often have difficulty supplying the knee-extension moments required during common mobility tasks. Existing powered orthoses that provide an assistive knee-extension moment are large and heavy, with power supplies that generally last less than two hours. A new device that provides a knee-extension-assist moment was designed to aid an individual with quadriceps muscle weakness to stand up from a seated position, sit from a standing position, and walk up and down an inclined surface. The knee-extension-assist (KEA) was designed as a modular component to be incorporated into existing knee-ankle-foot-orthoses (KAFO). The KEA consists of three springs that are compressed, as the knee is flexed under bodyweight, by cables that wrap around a sheave at the knee. The KEA returns the stored energy from knee flexion as an extension moment during knee extension. During swing or other non-weight bearing activities, the device is disengaged from the KAFO by decoupling the sheave from the KAFO knee joint, allowing free knee joint motion. A prototype was built and mechanically tested to determine KEA behaviour during loading and extension and to ensure proper KEA function. For biomechanical evaluation, able-bodied subjects used the prototype KEA while performing sit-to-stand, stand-to-sit, ramp ascent, and ramp descent tasks. The KEA facilitated sitting and standing, providing an average of 53 % of the required extension moment for the two participants, which allowed one participant to reduce quadriceps usage by 38 % and the other to perform sit-to-stand in a slower and more controlled manner that was not possible without the KEA. KEA use during ramp gait caused an overall increase in quadriceps activation by 76 %, on average, with use. Future efforts will be made to modify the design to improve functionality, especially for ramp gait, and to reduce device size and weight.
72

Less is more! less interaction, more accessible /

Franklin, Christopher A. January 2008 (has links)
Thesis (M.S.)--University of Nevada, Reno, 2008. / "May, 2008." Includes bibliographical references (leaves 53-54). Online version available on the World Wide Web.
73

TEACHER EDUCATORS' TECHNOLOGY DECISIONS AND THE EXTENT TO WHICH THEY MODEL TECHNOLOGIES FOR INCLUSIVE CLASSROOMS IN TEACHING METHOD COURSES

Kalonde, Gilbert 01 May 2014 (has links)
The purpose of this study was threefold; (1) to identify instructional technologies teacher educators use in teaching methods courses, (2) to identify the factors that influence their decisions for using such technologies in teaching methods courses, and (3) to investigate the extent to which teacher educators address the use of technology in inclusion in teaching methods courses. In this study, thirty teacher educators responded to fourteen Likert Scale questions, seven open-ended questions, listed technologies they use in the methods courses, and 5 of the teacher educators responded to another seven interview questions. The study used a concurrent mixed methods research design and used t-test, analysis of variances and Wilcoxon to analyze quantitative data. For qualitative data, collected through the Open-ended Questionnaire and Technology Inventory Checklist and the semi-structured interview responses were analyzed using open-coding. The results showed that teacher educators do use several technologies. However, the technologies they use are mostly instructional technologies and not inclusive technologies. In addition, the technologies used are more of content management like Desire to Learn and Black Board. Very few pedagogical and content delivery technologies are modeled to pre-service teachers. The study found that, regardless of teacher educators' experience, tenure and non-tenure, they all model technology similarly and not much variety of technology is used. They also minimally model inclusive technologies in the methods courses. The extent teacher educators model technology to pre-service teachers was low. While one third of the participants reported modeling technology for inclusion, the results also showed that two thirds of teacher educators modeled technology minimally. These results concurred with the results from the technology inventory list which showed that very few inclusive technologies are modeled to pre-service teachers in the methods courses. Study also found a non-significant effect on technology use and technologies used due gender, tenure, K-12 teaching experience or technology training. These results have an implication on how teacher educators integrate, use and model technology in the methods courses to pre-service teachers.
74

An exploration into the implementation of monitoring technologies in care homes for people with dementia

Hall, Alex James January 2016 (has links)
Background: An ageing society and rising prevalence in dementia are associated with rising demand for care home places. Monitoring technologies (e.g. bed-exit alarms; wearable location-tracking devices) are appealing because of their potential to enhance safety, increase resident freedom, and reduce staff burden. However, it is unclear how far use of such technologies can deliver potential benefits, and there are ethical challenges from their use. This study explored the implementation of monitoring technologies in care homes for people with dementia, to identify facilitators and barriers to the implementation of these technologies in practice. Methods: An embedded multiple-case study design was employed with 3 dementia-specialist care homes in North-West England. Data collection included 36 semi-structured interviews with staff, relatives and residents, informed by Normalization Process Theory to focus on individual and organisational factors within implementation; 175 hours’ non-participant observation; investigation of care records and technology manufacturer literature; and questionnaires to establish participant attitudes towards technologies. Qualitative data were analysed using Framework Analysis. Findings: 5 overarching themes emerged: (1) Reasons for using technologies; (2) How technologies were implemented; (3) What happened when using technologies; (4) Understanding of technologies; (5) Business and environmental influences. Mitigation of risk seemed to override other potential benefits (e.g. resident freedom) or ethical concerns (e.g. the remote monitoring of residents with impaired cognition), as a reason for use. This emphasis seemed to position monitoring technologies as being understood as fundamentally different to other interventions, and challenged adherence to philosophies of care emphasising resident choice. Some staff, relatives and residents did not seem to be involved in discussion and decision-making regarding technologies, and seemed to lack knowledge about technologies within the homes. Staff training appeared mainly informal, based upon assumptions of simplicity of use, which might not have been sufficient to ensure that staff fully understood the technologies. Staff understanding and awareness of the technologies appeared to be influenced in part by location, both organisationally (i.e. their role) and physically (i.e. within the building). Technical and physical properties of the technologies appeared to work in relation with the physical environments of the homes, which suggested that there may not be an ideal set of physical properties for any particular technology. Some technologies offered a range of functional and information-gathering capabilities, which at times were perceived to be useful complements to practice, but at other times less useful, particularly if they were imbued with a financial cost that was not justifiable from a business perspective. Conclusions: Care homes may need to consider greater involvement of all stakeholders in discussions and decisions regarding the use of monitoring technologies, in order to deepen understandings about the potential benefits and challenges from their use. There is also a need to consider the technical compatibility of technologies with the care home premises, and the financial implications from investing in technologies.
75

Design of a Knee Exoskeleton for Gait Assistance

January 2018 (has links)
abstract: The world population is aging. Age-related disorders such as stroke and spinal cord injury are increasing rapidly, and such patients often suffer from mobility impairment. Wearable robotic exoskeletons are developed that serve as rehabilitation devices for these patients. In this thesis, a knee exoskeleton design with higher torque output compared to the first version, is designed and fabricated. A series elastic actuator is one of the many actuation mechanisms employed in exoskeletons. In this mechanism a torsion spring is used between the actuator and human joint. It serves as torque sensor and energy buffer, making it compact and safe. A version of knee exoskeleton was developed using the SEA mechanism. It uses worm gear and spur gear combination to amplify the assistive torque generated from the DC motor. It weighs 1.57 kg and provides a maximum assistive torque of 11.26 N·m. It can be used as a rehabilitation device for patients affected with knee joint impairment. A new version of exoskeleton design is proposed as an improvement over the first version. It consists of components such as brushless DC motor and planetary gear that are selected to meet the design requirements and biomechanical considerations. All the other components such as bevel gear and torsion spring are selected to be compatible with the exoskeleton. The frame of the exoskeleton is modeled in SolidWorks to be modular and easy to assemble. It is fabricated using sheet metal aluminum. It is designed to provide a maximum assistive torque of 23 N·m, two times over the present exoskeleton. A simple brace is 3D printed, making it easy to wear and use. It weighs 2.4 kg. The exoskeleton is equipped with encoders that are used to measure spring deflection and motor angle. They act as sensors for precise control of the exoskeleton. An impedance-based control is implemented using NI MyRIO, a FPGA based controller. The motor is controlled using a motor driver and powered using an external battery source. The bench tests and walking tests are presented. The new version of exoskeleton is compared with first version and state of the art devices. / Dissertation/Thesis / Masters Thesis Mechanical Engineering 2018
76

GRAFCET como ferramenta no desenvolvimento de tecnologia assistiva / GRAFCET as a tool to develop assistive technology

Hamilton Luiz de Souza 01 October 2004 (has links)
A escassez de equipamentos e soluções à disposição das pessoas portadoras de necessidades especiais é evidente e, na maioria dos casos, não está entre as prioridades primárias dos governos, tanto nos países desenvolvidos como, e principalmente, nos subdesenvolvidos. O desenvolvimento de dispositivos a preços acessíveis é, desta forma, uma carência real. O alto custo de fabricação de dispositivos assistivos é oriundo da necessidade de se construí-los de forma personalizada o que geralmente utiliza o estado da arte de determinada tecnologia. Aglutinando então, tecnologias já difundidas com novas abordagens e ferramentas, foi implementado um dispositivo assistivo com um índice de \"personalização\" extremamente baixo e com custo acessível. O método GRAFCET como ferramenta de desenvolvimento, aliado a tecnologia FPGA, nas fases de prototipação e produção, mostram-se eficazes e de fácil aplicabilidade. Para essa finalidade foi desenvolvida uma ferramenta de conversão GRAFCET - Circuito Digital que facilita e torna possível não só na elaboração do esquema GRAFCET, mas principalmente possibilita antever semelhança com outras aplicações que não são facilmente visualizadas num primeiro momento, permitindo a sua simplificação. O dispositivo concebido, mostrou que, com pequenas modificações, é possível desenvolvê-los de forma que atenda não apenas um, mas vários portadores de necessidades especiais, viabilizando assim a diminuição dos custos de projeto, desenvolvimento e construção dos equipamentos que venham a atender estas pessoas, permitindo assim melhora significativa em sua qualidade de vida. / In all countries, particularly in underdeveloped ones, there are few equipment and solutions available to people with physical disabilities, whose needs hardly rank among the government\'s top priorities. Therefore, there is a real need to develop low cost equipment to people with disabilities. The high cost of production of assistive devices results from the necessity of building them in a customized way, generally employing some state-of-the-art technology. This work proposes using well known technologies as tools, in such a way to allow the design of assistive devices with a low degree of customization and, consequently, at low cost. Using GRAFCET as a development tool and FPGA technology have shown to be an effective and easily applicable approach during the phases of prototyping and production. We developed a tool that converts GRAFCET designs into a digital circuit. The tool makes it easier to develop GRAFCET schemes and highlights the similarities among different applications, which otherwise could pass unnoticed, resulting in simplified designs. With small modifications, the proposed device can meet the needs of several people with disabilities, resulting in lower design, development and building costs of equipment that can significantly improve their quality of life.
77

Using Sonic Enhancement to Augment Non-Visual Tabular Navigation

Cofino, Jonathan M, Barreto, Armando 22 May 2014 (has links)
More information is now readily available to computer users than at any time in human history; however, much of this information is often inaccessible to people with blindness or low-vision, for whom information must be presented non-visually. Currently, screen readers are able to verbalize on-screen text using text-to-speech (TTS) synthesis; however, much of this vocalization is inadequate for browsing the Internet. An auditory interface that incorporates auditory-spatial orientation was created and tested. For information that can be structured as a two-dimensional table, links can be semantically grouped as cells in a row within an auditory table, which provides a consistent structure for auditory navigation. An auditory display prototype was tested. Sixteen legally blind subjects participated in this research study. Results demonstrated that stereo panning was an effective technique for audio-spatially orienting non-visual navigation in a five-row, six-column HTML table as compared to a centered, stationary synthesized voice. These results were based on measuring the time- to-target (TTT), or the amount of time elapsed from the first prompting to the selection of each tabular link. Preliminary analysis of the TTT values recorded during the experiment showed that the populations did not conform to the ANOVA requirements of normality and equality of variances. Therefore, the data were transformed using the natural logarithm. The repeated-measures two-factor ANOVA results show that the logarithmically-transformed TTTs were significantly affected by the tonal variation method, F(1,15) = 6.194, p= 0.025. Similarly, the results show that the logarithmically transformed TTTs were marginally affected by the stereo spatialization method, F(1,15) = 4.240, p=0.057. The results show that the logarithmically transformed TTTs were not significantly affected by the interaction of both methods, F(1,15) = 1.381, p=0.258. These results suggest that some confusion may be caused in the subject when employing both of these methods simultaneously. The significant effect of tonal variation indicates that the effect is actually increasing the average TTT. In other words, the presence of preceding tones increases task completion time on average. The marginally-significant effect of stereo spatialization decreases the average log(TTT) from 2.405 to 2.264.
78

The MouthPad - a Tongue Interface for Hands-Free Computer Control

Draghici, Ovidiu January 2014 (has links)
Tongue-computer interfaces allow people with upper limb disability to control a computer with their tongue. A number of assistive devices, that make use of this technology, have been developed in the last two decades: some employ contact impedance, membrane switches, or miniature joysticks, while others use magnetic or piezoelectric sensors. This thesis proposes a new tongue-computer interface, which was designed to enable users to manipulate a computer pointer by moving the tip of their tongue over an intraoral electrode array. The system maps the contact between the tongue and the electrodes, detects the movements of the tongue, and translates it into pointer movements. Compared to similar devices, the MouthPad does not require any head gear or sensors, and does not employ heavy signal processing. The hardware is simplified by using a small number of electrodes and only one output channel, multiplexed over the electrode array. A low power footprint allows the potential miniaturization of the system, so that it could fit on palatal retainer, and allow for permanent unobtrusive usage. The performance of the device was evaluated by measuring the throughput and the accuracy as defined in ISO 9241-9 standard. Two extra measures proposed in the literature, target re-entry and movement offset, were used for the evaluation of the accuracy. The measured throughput values were situated between 78% and 88% of the throughput rates of regular computer joysticks.
79

Aging with Developmental Disabilities: Implications for Long-term Care

Dorrance, Kristin January 2015 (has links)
Background: Persons with developmental disabilities (DDs) represent about 1-3% of the total population in Canada; however, very little statistical data exists regarding this population in the context of long-term care (LTC). As the life expectation of these individuals increases, the distinct needs they have that are associated with aging should be addressed in LTC to help improve the quality and relevancy of the care they receive. Methods: An exploratory qualitative study. Semi-structured interviews were conducted. Open coding of interview transcripts, and content analysis was completed. Descriptive statistics of the sample were calculated using Excel. Results: All participants had experienced earlier functional decline which resulted in changes in their care needs. Often this meant needing to change their assistive devices. Many participants feared losing their independence as they aged. Conclusion: There is insufficient understanding of the unique needs that face people aging with DDs or how they access LTC. The preference for these individuals is to age in place, their independence must be maintained in order for this to be successful. Three factors help to facilitate this: assistive devices, attendant care and accessibility of health care services. Contexte: Les personnes ayant un handicaps developmental représentent environ 1-3% de la population totale au Canada. Cependant, très peu de données statistiques concernant cette population existent dans le contexte de soins de longue durée. L’espérance de vie de ces personnes augmente, les besoins distincts associés au vieillissement devraient être examinés pour aider à améliorer la qualité et la pertinence des soins qu'ils reçoivent dans les soins de longue durée. Méthodes: Une étude qualitative exploratoire. Des entrevues semi-structurées ont été menées. Les transcriptions d'entrevues ont été codées en utilisant un style de codage ouvert et l'analyse de contenu a été accomplie. Les statistiques descriptives des participants ont été calculées. Résultats: Plusieurs thèmes sont devenus apparents. Tous les participants avaient connu un déclin fonctionnel à un jeune âge qui a entraîné des changements dans leurs besoins de soins. Souvent, cela signifit avoir à changer leurs appareils et accessoires fonctionnels. De nombreux participants craignaient de perdre leur indépendance en vieillissant. Conclusion: Il y a une méconnaissance des besoins uniques auxquels font face les personnes vieillissant avec un handicap developmental et la façon dont ils accident aux soins de longue durée. La préférence pour ces personnes est de viellir en place, leur indépendance devant être maintenue pour que ce soit un succès. Trois facteurs contribuent à faciliter ceci: les appareils et accessoires fonctionnels, les soins auxiliaires et l'accessibilité aux services santé.
80

Development and Testing of an Unpowered Ankle Exoskeleton for Walking Assist

Leclair, Justin January 2016 (has links)
Assistive technologies traditionally rely on either strong actuation or passive structures to provide users with increased strength, support or the ability to perform lost functions. At one end of the spectrum are powered exoskeletons, which significantly increase a user’s strength, but require strong actuators, complex control systems, and heavy power sources. At the other end are orthoses, which are generally unpowered and lightweight devices that rely on their structure’s mechanical behaviour to enhance user’s support and stability. Ideally, assistive technologies should achieve both systems’ characteristics by enhancing human motion abilities while remaining lightweight and efficient. This can be achieved by using distinctive actuators to harness gait energy, towards enhancing human mobility and performance. Pneumatic Artificial Muscles (PAMs), compliant and flexible, yet powerful and lightweight, present a unique set of characteristics compared to other mechanical actuators in human mobility applications. However, given the need of a compressor and power source, PAMs present a significant challenge, limiting their application. In contrast, PAMs can be implemented as unpowered actuators that act as non-linear elastic elements. This thesis aims to develop a wearable lightweight unpowered ankle exoskeleton, which relies on the PAM to harness gait energy and compliment the human ankle biomechanical abilities at the push off movement, thusly assisting the user in propelling the body forward during walking. Presently, limited PAM models have been developed to analyse PAM passive behaviour and to assist in designing and selecting the appropriate PAM for unpowered application. Thus, this thesis aims to develop a passive model for the PAM. To mechanically validate the proposed exoskeleton design, a prototype is fabricated, and tested within an Instron tensile machine setup. The unpowered exoskeleton has shown its ability to provide significant contribution to the ankle timed precisely to release at the push off phase of the gait cycle. Furthermore, the proposed PAM stiffness model is validated experimentally, and accounts for muscle pressure, geometry, material and stretching velocity. This enables the evaluation of the impact of various parameters on the muscle behaviour and designs the PAM accordingly for the unpowered ankle exoskeleton

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