37 research outputs found

    Implementation of a low cost prototype for electrical impedance tomography based on the integrated circuit for body composition measurement AFE4300

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    Electrical impedance tomography (EIT) is a technique of image reconstruction of the electrical conductivity distribution in a tissue or region under observation. An electrical system for EIT comprises complex hardware and software modules, which are designed for a specific application which requires that the system to be able to detect conductivity variations within the study object. The Front-End for body composition measurement, AFE4300 from Texas Instruments allows a minimal implementation of an electrical impedance tomography system. It is the main device in the development of the EIT system presented in this paper, this device injects the current signal and measures the tensions generated on the study region boundary by 8 electrodes, the image reconstruction software was developed on the National Instruments platform Labview. The system includes a microcontroller PIC16F886 to configure the 8 channels for the definition of the patterns of injection and measurement of signals, also defines the current signal frequency and the bluetooth communication with the computer for the image reconstruction. The developed system was validated by a planar resistive phantom (CardiffEIT phantom), obtaining a stable voltage measurement every 50 ms per pair of electrodes, and a signal to noise ratio (SNR) maximum of 71.8 dB, for a current signal of 50 kHz. Additionally, tests were carried out in a saline tank with a concentration of 4 g/L, the developed system can simultaneously estimate the presence of conductive and non-conductive disturbances into the tank. CopyrightPeer ReviewedPostprint (published version

    How to deal with Haplotype data: An Extension to the Conceptual Schema of the Human Genome

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    [EN] The goal of this work is to describe the advantages of the application of Conceptual Modeling (CM) in complex domains, such as genomics. Nowadays, the study and comprehension of the human genome is a major challenge due to its high level of complexity. The constant evolution in the genomic domain contributes to the generation of ever larger amounts of new data, which means that if we do not manage it correctly data quality could be compromised (i.e., problems related with heterogeneity and inconsistent data). In this paper, we propose the use of a Conceptual Schema of the Human Genome (CSHG), designed to understand and improve our ontological commitment to the domain and also extend (enrich) this schema with the integration of a novel concept: Haplotypes. Our focus is on improving the understanding of the relationship between genotype and phenotype, since new findings show that this question is more complex than was originally thought. Here we present the first steps in our data management approach with haplotypes (variations, frequencies and populations) and discuss the database evolution to support this data. Each new version in our conceptual schema (CS) introduces changes to the underlying database structure that has essential and practical implications for better understanding and managing the relevant information. A solution based on conceptual models gives a clear definition of the domain with direct implications in the medical field (Precision Medicine), in which Genomic Information Systems (GeIS) play a very important role.[ES] El objetivo de este trabajo es describir las ventajas de la aplicación del Modelado Conceptual (MC) en dominios complejos, como la genómica. Hoy en día, el estudio y comprensión del genoma humano es un desafío importante debido a su alto nivel de complejidad. La constante evolución en el dominio genómico contribuye a la generación de grandes cantidades de datos nuevos, lo que significa que, si no lo gestionamos correctamente, la calidad de los mismos podría verse comprometida (por ejemplo: problemas relacionados con la heterogeneidad e inconsistencia de datos). En este trabajo se propone el uso de un Esquema Conceptual del Genoma Humano (ECGH), diseñado para comprender y mejorar nuestro compromiso ontológico con el dominio y extender este esquema con la integración de un nuevo concepto: Haplotipos. Nuestro objetivo es mejorar la comprensión de la relación entre genotipo-y-fenotipo, ya que los nuevos hallazgos muestran que este tema es mucho más complejo de lo que se pensaba originalmente. Aquí presentamos los primeros pasos en nuestro enfoque de gestión de datos haplotípicos (variaciones, frecuencias y poblaciones) y discutimos la evolución de la base de datos para apoyar dichos datos. Cada nueva versión de nuestro esquema conceptual (EC) introduce cambios en la estructura de la base de datos subyacente, que tiene implicaciones esenciales y prácticas con el fin de facilitar una mejor comprensión y gestión de la información relevante. Una solución basada en modelos conceptuales brinda una definición más clara del dominio con implicaciones directas en el campo médico (Medicina de precisión), en la que los Sistemas de Información Genómicos (GeIS) desempeñan un papel muy importante.The authors thanks to the members of the PROS Center Genome group for fruitful discussions. This work has been supported by the Ministry of Higher Education, Science and Technology (MESCyT) of the Dominican Republic, and It also has the support of Generalitat Valenciana through project IDEO (PROMETEOII/2014/039)Reyes Román, JF.; Pastor López, O.; Roldán Martínez, D.; Valverde Giromé, F. (2016). How to deal with Haplotype data: An Extension to the Conceptual Schema of the Human Genome. CLEI Electronic Journal. 19(3):1-21. https://doi.org/10.19153/cleiej.19.3.2S12119

    Políticas de Copyright de Publicações Científicas em Repositórios Institucionais: O Caso do INESC TEC

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    A progressiva transformação das práticas científicas, impulsionada pelo desenvolvimento das novas Tecnologias de Informação e Comunicação (TIC), têm possibilitado aumentar o acesso à informação, caminhando gradualmente para uma abertura do ciclo de pesquisa. Isto permitirá resolver a longo prazo uma adversidade que se tem colocado aos investigadores, que passa pela existência de barreiras que limitam as condições de acesso, sejam estas geográficas ou financeiras. Apesar da produção científica ser dominada, maioritariamente, por grandes editoras comerciais, estando sujeita às regras por estas impostas, o Movimento do Acesso Aberto cuja primeira declaração pública, a Declaração de Budapeste (BOAI), é de 2002, vem propor alterações significativas que beneficiam os autores e os leitores. Este Movimento vem a ganhar importância em Portugal desde 2003, com a constituição do primeiro repositório institucional a nível nacional. Os repositórios institucionais surgiram como uma ferramenta de divulgação da produção científica de uma instituição, com o intuito de permitir abrir aos resultados da investigação, quer antes da publicação e do próprio processo de arbitragem (preprint), quer depois (postprint), e, consequentemente, aumentar a visibilidade do trabalho desenvolvido por um investigador e a respetiva instituição. O estudo apresentado, que passou por uma análise das políticas de copyright das publicações científicas mais relevantes do INESC TEC, permitiu não só perceber que as editoras adotam cada vez mais políticas que possibilitam o auto-arquivo das publicações em repositórios institucionais, como também que existe todo um trabalho de sensibilização a percorrer, não só para os investigadores, como para a instituição e toda a sociedade. A produção de um conjunto de recomendações, que passam pela implementação de uma política institucional que incentive o auto-arquivo das publicações desenvolvidas no âmbito institucional no repositório, serve como mote para uma maior valorização da produção científica do INESC TEC.The progressive transformation of scientific practices, driven by the development of new Information and Communication Technologies (ICT), which made it possible to increase access to information, gradually moving towards an opening of the research cycle. This opening makes it possible to resolve, in the long term, the adversity that has been placed on researchers, which involves the existence of barriers that limit access conditions, whether geographical or financial. Although large commercial publishers predominantly dominate scientific production and subject it to the rules imposed by them, the Open Access movement whose first public declaration, the Budapest Declaration (BOAI), was in 2002, proposes significant changes that benefit the authors and the readers. This Movement has gained importance in Portugal since 2003, with the constitution of the first institutional repository at the national level. Institutional repositories have emerged as a tool for disseminating the scientific production of an institution to open the results of the research, both before publication and the preprint process and postprint, increase the visibility of work done by an investigator and his or her institution. The present study, which underwent an analysis of the copyright policies of INESC TEC most relevant scientific publications, allowed not only to realize that publishers are increasingly adopting policies that make it possible to self-archive publications in institutional repositories, all the work of raising awareness, not only for researchers but also for the institution and the whole society. The production of a set of recommendations, which go through the implementation of an institutional policy that encourages the self-archiving of the publications developed in the institutional scope in the repository, serves as a motto for a greater appreciation of the scientific production of INESC TEC

    Interpretability-oriented data-driven modelling of bladder cancer via computational intelligence

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    DISEÑO Y DESARROLLO DE UN SISTEMA DE INFORMACIÓN GENÓMICA BASADO EN UN MODELO CONCEPTUAL HOLÍSTICO DEL GENOMA HUMANO

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    Entender el genoma es un desafío de primer nivel, y esto se debe en gran parte a la gran cantidad de información existente en el dominio. Gracias a la aplicación de tecnologías NGS (Next-Generation Sequencing) se han generado enormes cantidades de datos -nuevos-, por lo que es fundamental construir estructuras que permitan organizar, procesar y explorar los datos con el fin de lograr un máximo provecho de la información y mejorar la comprensión del genoma humano. En este estudio se define un marco de trabajo centrado en el uso del Modelado Conceptual como estrategia esencial para la búsqueda de soluciones. En el campo médico este enfoque de desarrollo de software está ganando impulso por su impacto en el trabajo realizado por genetistas, laboratorios clínicos y bioinformáticos. Entender el genoma es un dominio de aplicación muy interesante debido a dos aspectos fundamentales: 1) en primer lugar, por las implicaciones sociológicas que supone plantearse la posibilidad de entender el lenguaje de la vida. 2) y, en segundo lugar, desde una perspectiva más práctica de aplicación en el ámbito clínico, debido a su repercusión en la generación de diagnósticos genómicos, los cuales juegan un papel importante dentro de la Medicina de Precisión. En esta Tesis Doctoral se propone utilizar un Modelo Conceptual del Genoma Humano (MCGH) como base fundamental para la generación de Sistemas de Información Genómicos (GeIS), con el objetivo de facilitar una conceptualización del dominio que permita i) alcanzar un conocimiento preciso del dominio y ii) ser capaces de llegar a una medicina de precisión (personalizada). Es importante resaltar que este Modelo Conceptual debe permanecer en constante crecimiento debido a los nuevos aportes que surgen en la comunidad científica. En este trabajo de investigación se presenta la evolución natural del modelo, así como un ejemplo de extensión del mismo, lo que permite comprobar su extensibilidad conservando su definición inicial. Además, se aplica el uso de una metodología (SILE) sistemática para la obtención de los datos desde los distintos repositorios genómicos, los cuales serán explotados a través herramientas software basadas en modelos conceptuales. Mediante el uso de este Modelo Conceptual holístico del Genoma Humano se busca comprender y mejorar el compromiso ontológico con el dominio -genómico-, y desarrollar Sistemas de Información Genómicos apoyados en Modelo Conceptuales para ayudar a la toma de decisiones en el entorno bioinformático.Understanding the genome is a first level challenge, and this is due in large part to a large amount of information in the domain. Thanks to the application of NGS (Next-Generation Sequencing) technologies, enormous amounts of -new- data have been generated, so it is essential to building structures that allow organizing, processing and exploring the data in order to obtain maximum benefit from the information and improve the understanding of the human genome. In this study we define a framework focused on the use of Conceptual Modeling as an essential strategy for finding solutions. In the medical field, this approach to software development is gaining momentum due to its impact on the work carried out by geneticists, clinical laboratories, and bioinformatics. Understanding the genome is a domain of very interesting application due to two fundamental aspects: 1) firstly, because of the sociological implications of considering the possibility of understanding the language of life. 2) secondly, from a more practical perspective of application in the clinical field, due to its repercussion in the generation of genomic diagnoses, which play an important role within Precision Medicine. In this PhD, it is proposed to use a Conceptual Model of the Human Genome (CMHG) as the fundamental basis for the generation of Genomic Information Systems (GeIS), with the aim of facilitating a conceptualization of the domain that allows i) to achieve a precise knowledge of the domain and ii) be able to increase and improve the adaptation of genomics in personalized medicine. It is important to highlight that this Conceptual Model must remain in constant growth due to the new contributions that arise in the scientific community. In this research work the natural evolution of the model is presented, as well as an example of its extension, which allows verifying its extensibility while preserving its initial definition. In addition, the use of a systematic methodology is applied to obtain the data from the different genomic repositories, which will be exploited through software tools based on conceptual models. Through the use of this Holistic Conceptual Model of the Human Genome, we seek to understand and improve the ontological commitment to the -genomic- domain, and develop GeIS supported in Conceptual Model to help decision making in the bioinformatic environment in order to provide better treatment to the patients.Entendre el genoma és un desafiament de primer nivell, i açò es deu en gran part a la gran quantitat d'informació existent en el domini. Gràcies a l'aplicació de tecnologies NGS (Next-Generation Sequencing) s'han generat enormes quantitats de dades - nous-, per la qual cosa és fonamental construir estructures que permeten organitzar, processar i explorar les dades a fi d'aconseguir un màxim profit de la informació i millorar la comprensió del genoma humà. En este estudi es definix un marc de treball centrat en l'ús del Modelatge Conceptual com a estratègia essencial per a la busca de solucions. En el camp mèdic este enfocament de desenvolupament de programari està guanyant impuls pel seu impacte en el treball realitzat per genetistes, laboratoris clínics i bioinformàtics. Entendre el genoma és un domini d'aplicació molt interessant a causa de dos aspectes fonamentals: 1) en primer lloc, per les implicacions sociològiques que suposa plantejar-se la possibilitat d'entendre el llenguatge de la vida. 2) i, en segon lloc, des d'una perspectiva més pràctica d'aplicació en l'àmbit clínic, a causa de la seua repercussió en la generació de diagnòstics genòmics, els quals juguen un paper important dins de la Medicina de Precisió. En esta Tesi Doctoral es proposa utilitzar un Model Conceptual del Genoma Humà (MCGH) com a base fonamental per a la generació de Sistemes d'Informació Genòmics (GeIS), amb l'objectiu de facilitar una conceptualització del domini que permeta i) aconseguir un coneixement precís del domini i ii) ser capaços d'arribar a una medicina de precisió (personalitzada). És important ressaltar que este Model Conceptual ha de romandre en constant creixement degut a les noves aportacions que sorgixen en la comunitat científica. En este treball d'investigació es presenta l'evolució natural del model, així com un exemple d'extensió del mateix, la qual cosa permet comprovar la seua extensibilitat conservant la seua definició inicial. A més, s'aplica l'ús d'una metodologia (SILE) sistemàtica per a l'obtenció de les dades des dels distints reposadors genòmics, els quals seran explotats a través ferramentes de programari basades en models conceptuals. Per mitjà de l'ús d'este Model Conceptual holístic del Genoma Humà es busca comprendre i millorar el compromís ontològic amb el domini -genòmic-, i desenvolupar Sistemes d'Informació Genòmics recolzats en Model Conceptuals per ajudar a la presa de decisions en l'entorn bioinformàtic.Reyes Román, JF. (2018). DISEÑO Y DESARROLLO DE UN SISTEMA DE INFORMACIÓN GENÓMICA BASADO EN UN MODELO CONCEPTUAL HOLÍSTICO DEL GENOMA HUMANO [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/99565TESI

    Prediction Of Heart Failure Decompensations Using Artificial Intelligence - Machine Learning Techniques

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    Los apartados 4.41, 4.4.2 y 4.4.3 del capítulo 4 están sujetos a confidencialidad por la autora. 203 p.Heart failure (HF) is a major concern in public health. Its total impact is increased by its high incidence and prevalence and its unfavourable medium-term prognosis. In addition, HF leads to huge health care resource consumption. Moreover, efforts to develop a deterministic understanding of rehospitalization have been difficult, as no specific patient or hospital factors have been shown to consistently predict 30-day readmission after hospitalization for HF.Taking all these facts into account, we wanted to develop a project to improve the assistance care of patients with HF. Up to know, we were using telemonitoring with a codification system that generated alarms depending on the received values. However, these simple rules generated large number of false alerts being, hence, not trustworthy. The final aims of this work are: (i) asses the benefits of remote patient telemonitoring (RPT), (ii) improve the results obtained with RPT using ML techniques, detecting which parameters measured by telemonitoring best predict HF decompensations and creating predictive models that will reduce false alerts and detect early decompensations that otherwise will lead to hospital admissions and (iii) determine the influence of environmental factors on HF decompensations.All in all, the conclusions of this study are:1. Asses the benefits of RPT: Telemonitoring has not shown a statistically significant reduction in the number of HF-related hospital admissions. Nevertheless, we have observed a statistically significant reduction in mortality in the intervention group with a considerable percentage of deaths from non-cardiovascular causes. Moreover, patients have considered the RPT programme as a tool that can help them in the control of their chronic disease and in the relationship with health professionals.2. Improve the results obtained with RPT using machine learning techniques: Significant weight increases, desaturation below 90%, perception of clinical worsening, including development of oedema, worsening of functional class and orthopnoea are good predictors of heart failure decompensation. In addition, machine learning techniques have improved the current alerts system implemented in our hospital. The system reduces the number of false alerts notably although it entails a decrement on sensitivity values. The best results are achieved with the predictive model built by applying NB with Bernoulli to the combination of telemonitoring alerts and questionnaire alerts (Weight + Ankle + well-being plus the yellow alerts of systolic blood pressure, diastolic blood pressure, O2Sat and heart rate). 3. Determine the influence of environmental factors on HF decompensations: Air temperature is the most significant environmental factor (negative correlation) in our study, although some other attributes, such as precipitation, are also relevant. This work also shows a consistent association between increasing levels SO2 and NOX air and HF hospitalizations

    Prediction Of Heart Failure Decompensations Using Artificial Intelligence - Machine Learning Techniques

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    Los apartados 4.41, 4.4.2 y 4.4.3 del capítulo 4 están sujetos a confidencialidad por la autora. 203 p.Heart failure (HF) is a major concern in public health. Its total impact is increased by its high incidence and prevalence and its unfavourable medium-term prognosis. In addition, HF leads to huge health care resource consumption. Moreover, efforts to develop a deterministic understanding of rehospitalization have been difficult, as no specific patient or hospital factors have been shown to consistently predict 30-day readmission after hospitalization for HF.Taking all these facts into account, we wanted to develop a project to improve the assistance care of patients with HF. Up to know, we were using telemonitoring with a codification system that generated alarms depending on the received values. However, these simple rules generated large number of false alerts being, hence, not trustworthy. The final aims of this work are: (i) asses the benefits of remote patient telemonitoring (RPT), (ii) improve the results obtained with RPT using ML techniques, detecting which parameters measured by telemonitoring best predict HF decompensations and creating predictive models that will reduce false alerts and detect early decompensations that otherwise will lead to hospital admissions and (iii) determine the influence of environmental factors on HF decompensations.All in all, the conclusions of this study are:1. Asses the benefits of RPT: Telemonitoring has not shown a statistically significant reduction in the number of HF-related hospital admissions. Nevertheless, we have observed a statistically significant reduction in mortality in the intervention group with a considerable percentage of deaths from non-cardiovascular causes. Moreover, patients have considered the RPT programme as a tool that can help them in the control of their chronic disease and in the relationship with health professionals.2. Improve the results obtained with RPT using machine learning techniques: Significant weight increases, desaturation below 90%, perception of clinical worsening, including development of oedema, worsening of functional class and orthopnoea are good predictors of heart failure decompensation. In addition, machine learning techniques have improved the current alerts system implemented in our hospital. The system reduces the number of false alerts notably although it entails a decrement on sensitivity values. The best results are achieved with the predictive model built by applying NB with Bernoulli to the combination of telemonitoring alerts and questionnaire alerts (Weight + Ankle + well-being plus the yellow alerts of systolic blood pressure, diastolic blood pressure, O2Sat and heart rate). 3. Determine the influence of environmental factors on HF decompensations: Air temperature is the most significant environmental factor (negative correlation) in our study, although some other attributes, such as precipitation, are also relevant. This work also shows a consistent association between increasing levels SO2 and NOX air and HF hospitalizations

    Envelhecimento vocal: estudo acústico-articulatório das alterações de fala com a idade

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    Background: Although the aging process causes specific alterations in the speech organs, the knowledge about the age effects in speech production is still disperse and incomplete. Objective: To provide a broader view of the age-related segmental and suprasegmental speech changes in European Portuguese (EP), considering new aspects besides static acoustic features, such as dynamic and articulatory data. Method: Two databases, with speech data of Portuguese adult native speakers obtained through standardized recording and segmentation procedures, were devised: i) an acoustic database containing all EP oral vowels produced in similar context (reading speech), and also a sample of semispontaneous speech (image description) collected from a large sample of adults between the ages 35 and 97; ii) and another with articulatory data (ultrasound (US) tongue images synchronized with speech) for all EP oral vowels produced in similar contexts (pseudowords and isolated) collected from young ([21-35]) and older ([55-73]) adults. Results: Based on the curated databases, various aspects of the aging speech were analyzed. Acoustically, the aging speech is characterized by: 1) longer vowels (in both genders); 2) a tendency for F0 to decrease in women and slightly increase in men; 3) lower vowel formant frequencies in females; 4) a significant reduction of the vowel acoustic space in men; 5) vowels with higher trajectory slope of F1 (in both genders); 6) shorter descriptions with higher pause time for males; 7) faster speech and articulation rate for females; and 8) lower HNR for females in semi-spontaneous speech. In addition, the total speech duration decrease is associated to non-severe depression symptoms and age. Older adults tended to present more depressive symptoms that could impact the amount of speech produced. Concerning the articulatory data, the tongue tends to be higher and more advanced with aging for almost all vowels, meaning that the vowel articulatory space tends to be higher, advanced, and bigger in older females. Conclusion: This study provides new information on aging speech for a language other than English. These results corroborate that speech changes with age and present different patterns between genders, and also suggest that speakers might develop specific articulatory adjustments with aging.Contextualização: Embora o processo de envelhecimento cause alterações específicas no sistema de produção de fala, o conhecimento sobre os efeitos da idade na fala é ainda disperso e incompleto. Objetivo: Proporcionar uma visão mais ampla das alterações segmentais e suprassegmentais da fala relacionadas com a idade no Português Europeu (PE), considerando outros aspetos, para além das características acústicas estáticas, tais como dados dinâmicos e articulatórios. Método: Foram criadas duas bases de dados, com dados de fala de adultos nativos do PE, obtidos através de procedimentos padronizados de gravação e segmentação: i) uma base de dados acústica contendo todas as vogais orais do PE em contexto semelhante (leitura de palavras), e também uma amostra de fala semiespontânea (descrição de imagem) produzidas por uma larga amostra de indivíduos entre os 35 e os 97 anos; ii) e outra com dados articulatórios (imagens de ultrassom da língua sincronizadas com o sinal acústico) de todas as vogais orais do PE produzidas em contextos semelhantes (pseudopalavras e palavras isoladas) por adultos de duas faixas etárias ([21-35] e [55-73]). Resultados: Tendo em conta as bases de dados curadas, foi analisado o efeito da idade em diversas características da fala. Acusticamente, a fala de pessoas mais velhas é caracterizada por: 1) vogais mais longas (ambos os sexos); 2) tendência para F0 diminuir nas mulheres e aumentar ligeiramente nos homens; 3) diminuição da frequência dos formantes das vogais nas mulheres; 4) redução significativa do espaço acústico das vogais nos homens; 5) vogais com maior inclinação da trajetória de F1 (ambos os sexos); 6) descrições mais curtas e com maior tempo de pausa nos homens; 7) aumento da velocidade articulatória e da velocidade de fala nas mulheres; e 8) diminuição do HNR na fala semiespontânea em mulheres. Além disso, os idosos tendem a apresentar mais sintomas depressivos que podem afetar a quantidade de fala produzida. Em relação aos dados articulatórios, a língua tende a apresentar-se mais alta e avançada em quase todas as vogais com a idade, ou seja o espaço articulatório das vogais tende a ser maior, mais alto e avançado nas mulheres mais velhas. Conclusão: Este estudo fornece novos dados sobre o efeito da idade na fala para uma língua diferente do inglês. Os resultados corroboram que a fala sofre alterações com a idade, que diferem em função do género, sugerindo ainda que os falantes podem desenvolver ajustes articulatórios específicos com a idade.Programa Doutoral em Gerontologia e Geriatri

    Ergowear: desenvolvimento de um vestuário inteligente para monitorização postural e biofeedback

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    Dissertação de mestrado em Engenharia Biomédica (especialização em Eletrónica Médica)Atualmente, as Lesões Musculoesqueléticas Relacionadas com o Trabalho (LMERT) são considera das o ”problema relacionado com o trabalho mais prevalente”na União Europeia, levando a um custo estimado de cerca de 240 biliões de euros. Em casos mais severos, estes distúrbios podem causar danos vitalícios à saúde do trabalhador, reduzindo a sua qualidade de vida. De facto, LMERTs são con sideradas a principal causa da reforma precoce dos trabalhadores. Foi reportado que os segmentos da parte superior do corpo são mais suceptíveis ao desenvolvimento de LMERTs. Para mitigar a prevalência de LMERTs, ergonomistas maioritariamente aplicam métodos de avaliação observacionais, que são alta mente dependentes da experiência do analista, e apresentam baixa objetividade e repetibilidade. Desta maneira, esforços têm sido feitos para desenvolver ferramentas de avaliação ergonómica baseadas na instrumentação, para compensar essas limitações. Além disso, com a ascensão do conceito da indústria 5.0, o trabalhador humano volta a ser o foco principal na indústria, juntamente com o robô colaborativo. No entanto, para alcançar uma relação verdadeiramente colaborativa e simbiótica entre o trabalhador e o robô, este último precisa de reconhecer as intenções do trabalhador. Para superar este obstáculo, sis temas de captura de movimento podem ser integrados nesta estrutura, fornecendo dados de movimento ao robô colaborativo. Esta dissertação visa a melhoria de um sistema de captura de movimento autónomo, da parte supe rior do corpo, de abordagem inercial que servirá, não apenas para monitorizar a postura do trabalhador, mas também avaliar a ergonomia do usuário e fornecer consciencialização postural ao usuário, por meio de motores de biofeedback. Além disso, o sistema foi já idealizado tendo em mente a sua integração numa estrutura colaborativa humano-robô. Para atingir estes objetivos, foi aplicada uma metodologia de design centrado no utilizador, começando pela análise do Estado da Arte, a avaliação das limitações do sistema anterior, a definição dos requisitos do sistema, o desenvolvimento da peça de vestuário, arquite tura do hardware e arquitetura do software do sistema. Por fim, o sistema foi validado para verificar se estava em conformidade com os requisitos especificados. O sistema é composto por 9 Unidades de Medição Inercial (UMI), posicionados na parte inferior e superior das costas, cabeça, braços, antebraços e mãos. Também foi integrado um sistema de atuação, para biofeedback postural, composto por 6 motores vibrotáteis, localizados na região lombar e próximo do pescoço, cotovelos e pulsos. O sistema é alimentado por uma powerbank e todos os dados adquiridos são enviados para uma estação de processamento, via WiFi (User Datagram Protocol (UDP)), garantindo autonomia. O sistema tem integrado um filtro de fusão Complementar Extendido e uma sequência de calibração Sensor-para-Segmento estática, de maneira a aumentar a precisão da estimativa dos ângulos das articulações. Além disso, o sistema é capaz de amostrar os dados angulares a 240 Hz, enquanto que o sistema anterior era capaz de amostrar no máximo a 100 Hz, melhorando a resolução da aquisição dos dados. O sistema foi validado em termos de hardware e usabilidade. Os testes de hardware abordaram a caracterização da autonomia, frequência de amostragem, robustez mecânica e desempenho da comuni cação sem fio do sistema, em diversos contextos, e também para verificar se estes estão em conformidade com os requisitos técnicos previamente definidos, que foi o caso. Adicionalmente, as especificações da nova versão do sistema foram comparadas com a anterior, onde se observou uma melhoria direta signifi cativa, como por exemplo, maior frequência de amostragem, menor perda de pacote, menor consumo de corrente, entre outras, e com sistemas comerciais de referência (XSens Link). Testes de usabilidade foram realizados com 9 participantes que realizaram vários movimentos uniarticulares e complexos. Após os testes, os usuários responderam a um questionário baseado na Escala de Usabilidade do Sistema (EUS). O sistema foi bem aceite pelos os usuários, em termos de estética e conforto, em geral, comprovando um elevado nível de vestibilidade.Nowadays, Work-Related Musculoskeletal Disorders (WRMSDs) are considered the ”most prevalent work-related problem” in the European Union (EU), leading to an estimated cost of about 240 billion EUR. In more severe cases, these disorders can cause life-long impairments to the workers’ health, reducing their quality of life. In fact, WRMSDs are the main cause for the workers’ early retirement. It was reported that the upper body segments of the worker are more susceptible to the development of WRMSDs. To mitigate the prevalence of WRMSD, ergonomists mostly apply observational assessment methods, which are highly dependant on the analyst’s expertise, have low objectivity and repeatability. Therefore, efforts have been made to develop instrumented-based ergonomic assessment tools, to compensate for these limitations. Moreover, with the rise of the 5.0 industry concept, the human worker is once again the main focus in the industry, along with the Collaborative Robot (cobot). However, to achieve a truly collaborative relation between the worker and the cobot, the latter needs to know the worker’s intentions. To surpass this obstacle, Motion Capture (MoCap) systems can be integrated in this framework, providing motion data to the cobot. This dissertation aims at the improvement of a stand-alone, upper-body, inertial, MoCap system, that will serve to not only monitor the worker’s posture, but also to assess the user’s ergonomics and provide posture awareness to the user, through biofeedback motors. Furthermore, it was also designed to integrate a human-robot collaborative framework. To achieve this, a user-centred design methodology was applied, starting with analyzing the State of Art (SOA), assessing the limitations of the previous system, defining the system’s requirements, developing the garment, hardware architecture and software architecture of the system. Lastly, the system was validated to ascertain if it is in conformity with the specified requirements. The developed system is composed of 9 Inertial Measurement Units (IMUs), placed on the lower and upper back, head, upper arms, forearms and hands. An actuation system was also integrated, for postural biofeedback, and it is comprised of 6 vibrotactile motors, located in the lower back, and in close proximity to the neck, elbows and wrists. The system is powered by a powerbank and all of the acquired data is sent to a main station, via WiFi (UDP), granting a standalone characteristic. The system integrates an Extended Complementary Filter (ECF) and a static Sensor-to-Segment (STS) calibration sequence to increase the joint angle estimation accuracy. Furthermore, the system is able to sample the angular data at 240 Hz, while the previous system was able to sample it at a maximum 100 Hz, improving the resolution of the data acquisition. The system was validated in terms of hardware and usability. The hardware tests addressed the char acterization of the system’s autonomy, sampling frequency, mechanical robustness and wireless commu nication performance in different contexts, and ascertain if they comply with the technical requirements, which was the case. Moreover, the specifications of the new version were compared with the previous one, where a significant direct improvement was observed, such as, higher sampling frequency, lower packet loss, lower current consumption, among others, and with a commercial system of reference (XSens Link). Usability tests were carried out with 9 participants who performed several uni-joint and complex motions. After testing, users answered a questionnaire based on the System Usability Scale (SUS). The system was very well accepted by the participants, regarding aesthetics and overall comfort, proving to have a high level of wearability
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