569 research outputs found
A personalized rehabilitation system based on wireless motion capture sensors
We live in an aging society, an issue that will be exacerbated in the coming decades, due to low birth rates
and increasing life expectancy. With the decline in physical and cognitive functions with age, it is of the
utmost importance to maintain regular physical activity,in order to preserve an individualâs mobility, motor
capabilities and coordination. Within this context, thispaper describes the development of a wireless sensor
network and its application in a human motion capturesystem based on wearable inertial and magnetic
sensors. The goal is to enable, through continuous real-time monitoring, the creation of a personalized
home-based rehabilitation system for the elderly population and/or injured people. Within this system, the
user can benefit from an assisted mode, in which their movements can be compared to a reference motion
model of the same movements, resulting in visual feedback alerts given by the application. This motion
model can be created previously, in a âlearning phaseâ, under supervision of a caregiver.Fundação para a CiĂȘncia e a Tecnologia (FCT
Programa GOAL - Going for the Goal / Lutar pelos objectivos: um programa de competĂȘncias de vida no ensino bĂĄsico
O principal objectivo deste estudo consistiu em caracterizar e analisar diferenças entre dois grupos (um grupo experimental e um grupo controlo) de crianças que frequentavam o 4.Âș ano de escolaridade no ano lectivo 2001/2002 em Leiria. O grupo experimental foi sujeito Ă aplicação de um programa de competĂȘncias de vida (Programa GOAL â Going for the Goal / Lutar pelos Objectivos) e o grupo controlo apenas participou nos momentos do prĂ© e do pĂłs-teste. Os sujeitos de ambos os grupos fizeram uma auto-avaliação (Escala de auto-conceito de Piers-Harris para crianças); foram avaliados pelos pares (teste sociomĂ©trico) e pelos professores (inquĂ©rito por questionĂĄrio) em dois momentos distintos, antes e apĂłs o tratamento. Os resultados da auto-avaliação e da avaliação pelos pares sugerem nĂŁo existir diferenças estatisticamente significativas entre os dois grupos. Relativamente aos momentos de avaliação (prĂ©-teste e pĂłs-teste), os resultados sugerem diferenças estatisticamente significativas na variĂĄvel auto-conceito. No que concerne Ă avaliação por parte dos professores, verifica-se um maior nĂșmero de respostas por parte dos docentes do GE, tanto no momento do prĂ© como do pĂłs-teste. No prĂ©-teste, as respostas relativas ao GE mostram uma diferença de mĂ©dias e de dispersĂŁo de resultados face ao GC. A maior parte das questĂ”es apresenta uma mĂ©dia superior no GE e uma maior dispersĂŁo no GC. No pĂłs-teste, a mĂ©dia das respostas Ă© superior no GC e a dispersĂŁo Ă© menor no GE
Vital signs monitoring and management using mobile devices
Constant breakthroughs in medical sensor technology
and mobile devices fields, combined with growing wireless
communication capabilities, have made possible the emergence of
new health monitoring paradigms. The ever-increasing features
of PDAs and smartphones make them a vital component in
innovative health monitoring systems. In this paper, we introduce
a handset mobile monitoring and management system, developed
as complement to a complete vital signs monitoring project
(MOHLL). The main purpose of this system is to provide
physicians with real-time visualization of the patientsâ vital
parameters, namely the ECG trace, heart rate, and body
temperature, through an Internet-connected PDA.Clinical and financial support for the case-study has been provided by Grupo AMI - Assistencia Medica Integral (Casa de Saude de Guimaraes, SA), Portugal, under the partnership established between this healthcare company and the University of Minho
A telerehabilitation system based on wireless motion capture sensors
The constant growth of the elderly population in the world creates new challenges and opportunities in health care systems. New technological solutions have to be found in order to meet the needs and demands of our aging society. The welfare and quality of life of the elderly population must be a priority. Continuous physical activity will play an important role, due to the increase of the retirement age. However, physiotherapy can be expensive, even when the desire movements are autonomous and simple, also requires people to move to rehabilitation centres. Within this context, this paper describes the development and preliminary tests of a wireless sensor network, based on wearable inertial and magnetic sensors, applied to the capture of human motion. This will enable a personalized home-based rehabilitation system for the elderly or people in remote physical locations.Project âAAL4ALLâ, co-financed by the European Community Fund FEDER through COMPETE â Programa Operacional Factores de Competitividade (POFC).FCT â Foundation for Science and Technology â Lisbon, Portugal, through project PEst-C/CTM/LA0025/2013
Sistema de fabrico råpido de implantes ortopédicos
Este estudo teve como objectivo o desenvolvimento uma metodologia
de fabrico råpido de implantes ortopédicos, em simultaneidade
com a intervenção cirĂșrgica, considerando duas
potenciais aplicaçÔes na årea ortopédica: o fabrico de implantes
anatomicamente adaptados e o fabrico de implantes para substituição
de perdas ósseas. A inovação do trabalho desenvolvido
consiste na obtenção in situ da geometria do implante, através
da impressão directa de um material elastomérico (polivinilsiloxano)
que permite obter com grande exactidĂŁo a geometria
pretendida. Após digitalização do modelo obtido em material
elastomérico, o implante final é fabricado por maquinagem recorrendo
a um sistema de CAD/CAM dedicado. O implante
após esterilização, pode ser colocado no paciente. O conceito
foi desenvolvido com recurso a tecnologias disponĂveis comercialmente
e de baixo custo. O mesmo foi testado sob a forma
de uma artroplastia da anca realizada in vivo numa ovelha. O
acréscimo de tempo de cirurgia foi de 80 minutos sendo 40
directamente resultantes do processo de fabrico do implante.
O sistema desenvolvido revelou-se eficiente no alcance dos
objectivos propostos, possibilitando o fabrico de um implante
durante um perĂodo de tempo perfeitamente compatĂvel com o
tempo de cirurgia.This study, aimed the development of a methodology for rapid
manufacture of orthopedic implants simultaneously with the
surgical intervention, considering two potential applications
in the fields of orthopedics: the manufacture of anatomically
adapted implants and implants for bone loss replacement. This
work innovation consists on the capitation of the in situ geometry
of the implant by direct capture of the shape using an elastomeric
material (polyvinylsiloxane) which allows fine detail
and great accuracy of the geometry. After scanning the elastomeric
specimen, the implant is obtained by machining using a
CNC milling machine programmed with a dedicated CAD/CAM
system. After sterilization, the implant is able to be placed on
the patient. The concept was developed using low cost technology
and commercially available. The system has been tested in
an in vivo hip arthroplasty performed on a sheep. The time increase
of surgery was 80 minutes being 40 minutes the time of
implant manufacturing. The system developed has been tested
and the goals defined of the study achieved enabling the rapid
manufacture of an implant in a time period compatible with the
surgery time
Biomechanical behaviour of cancellous bone on patellofemoral arthroplasty with journey prosthesis : a finite element study
Isolated patellofemoral (PF) arthritis of the knee is a common cause of anterior knee pain and disability. Patellofemoral arthroplasty (PFA) is a bone conserving solution for patients with PF degeneration. Failure mechanisms of PFA include growing tibiofemoral arthritis and loosening of components. The implant loosening can be associated with bone resorption, or fatigue-failure of bone by overload. This research work aims at determining the structural effects of the implantation of PF prosthesis Journey PFJ (Smith&Nephew, USA) on femur cancellous bone. For this purpose, the finite element (FE) method is considered to perform computational simulations for different conditions, such as well-fixed and loosening scenarios. From the global results obtained, in the well-fixed scenario, a strain decrease on cancellous bone was noticed, which can be related to bone resorption. In the loosening scenario, when the cement layer becomes inefficient, a significant increase of cancellous bone strain was observed, which can be associated with bone fatigue-failure. These strain changes suggest a weakness of the femur after PFA.Fundação para a CiĂȘncia e a Tecnologia (FCT
A wireless posture monitoring system for personalized home-based rehabilitation
We live in an aging society, an issue that will be exacerbated in the coming decades, due to low birth
rates and increasing life expectancy. With the decline in physical and cognitive functions with age, it is of the
utmost importance to maintain regular physical activity, in order to preserve an individualâs mobility, motor
capabilities and coordination. Within this context, this paper describes the development of a wireless sensor
network and its application in a human motion capture system based on wearable inertial and magnetic sensors.
The goal is to enable, through continuous real-time monitoring, the creation of a personalized home-based
rehabilitation system for the elderly population and/or injured people. Within this system, the user can benefit
from an assisted mode, in which their movements can be compared to a reference motion model of the same
movements, resulting in visual feedback alerts given by the application. This motion model can be created
previously, in a âlearning phaseâ, under supervision of a caregiver.Project âAAL4ALLâ, co-financed by the
European Community Fund FEDER through
COMPETE â Programa Operacional Factores de
Competitividade (POFC). This work is funded by
FEDER funds through the COMPETE 2020
Programme and National Funds through FCT -
Portuguese Foundation for Science and Technology
under the projects UID/CTM/50025/2013 and
UID/EEA/04436/2013.info:eu-repo/semantics/publishedVersio
Review of fiber-optic pressure sensors for biomedical and biomechanical applications
As optical fibers revolutionize the way data is carried in telecommunications, the same is happening in the world of sensing. Fiber-optic sensors (FOS) rely on the principle of changing the properties of light that propagate in the fiber due to the effect of a specific physical or chemical parameter. We demonstrate the potentialities of this sensing concept to assess pressure in biomedical and biomechanical applications. FOSs are introduced after an overview of conventional sensors that are being used in the field. Pointing out their limitations, particularly as minimally invasive sensors, is also the starting point to argue FOSs are an alternative or a substitution technology. Even so, this technology will be more or less effective depending on the efforts to present more affordable turnkey solutions and peer-reviewed papers reporting in vivo experiments and clinical trials.info:eu-repo/semantics/publishedVersio
Design of laminated structures using piezoelectric materials
Composite structures incorporating piezoelectric sensors and actuators are increasingly becoming important due to the offer of potential benefits in a wide range of engineering applications such as vibration and noise supression, shape control and precisition positioning. This paper presents a finit element formulation based on classical laminated plate theory for laminated structures with integrated piezoelectric layers or patches, acting as actuators. The finite element model is a single layer triangular nonconforming plate/shell element with 18 degrees of freedom for the generalized displacements, and one electrical potential degree of freedom for each piezsoelectric elementlayer or patch, witch are surface bonded on the laminate. An optimization of the patches position is performed to maximize the piezoelectric actuators efficiency as well as, the electric potential distribuition is search to reach the specified structure transverse displacement distribuition (shape control). A gradient based algorithm is used for this purpose. The model is applied in the optimization of illustrative laminated plate cases, and the results are presented and discussed
Shape control of laminated panels using piezoelectric actuators
This paper presents a finite element formulation based on the classical laminated plate theory for laminated structures with integrated piezoelectric layers or patches, acting as actuators.The finite element model is a single layer trinaguular nonconforming plate/shell element with 18 degrees of fredom for the generalized displacements, and one electrical potential degree of freedom for each piezoelectric element elemenet layer or patch. An optimization of the patches position is perfomed to maximize the piezoelectric actuators efficiency as well as,the electric potential distribution is serach to reach the specified strusctura transverse displacement distribution is search to reach the specified structures trsnsverse displacement distribution (shape control). A gradient based algorithm is used for this purpose.Results are presented and discussed
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