Wearable System for Biosignal Acquisition and Monitoring Based on Reconfigurable Technologies

Wearable monitoring devices are now a usual commodity in the market, especially for the monitoring of sports and physical activity. However, specialized wearable devices remain an open field for high-risk professionals, such as military personnel, fire and rescue, law enforcement, etc. In this work, a prototype wearable instrument, based on reconfigurable technologies and capable of monitoring electrocardiogram, oxygen saturation, and motion, is presented. This reconfigurable device allows a wide range of applications in conjunction with mobile devices. As a proof-of-concept, the reconfigurable instrument was been integrated into ad hoc glasses, in order to illustrate the non-invasive monitoring of the user. The performance of the presented prototype was validated against a commercial pulse oximeter, while several alternatives for QRS-complex detection were tested. For this type of scenario, clustering-based classification was found to be a very robust option.This work was funded by Banco Santander and Centro Mixto UGR-MADOC through project SIMMA (code 2/16). The contribution of Víctor Toral was funded by the University of Granada through a grant from the “Iniciación a la investigación 2016” program. The contribution of Antonio García was partially funded by Spain’s Ministerio de Educación, Cultura y Deporte (Programa Estatal de Promoción del Talento y su Empleabilidad en I+D+i, Subprograma Estatal de Movilidad, within Plan Estatal de Investigación Científica y Técnica y de Innovación 2013-2016) under a “Salvador de Madariaga” grant (PRX17/00287). The contribution of Francisco J. Romero was funded by Spain’s Ministerio de Educación, Cultura y Deporte under a FPU grant (FPU16/01451). The contribution of Francisco M. Gómez-Campos was funded by Spain’s Ministerio de Economía, Industria y Competitividad under Project ENE2016_80944_R

Remote health monitoring system for the elderly based on mobile computing and IoT

This document presents the work done in the Master’s thesis in Telecommunications and Computer Engineering and describes the development, implementation and subsequent of a Remote Health Monitoring System for the Elderly based on Mobile Computing and IoT. Due to increasing technological innovation over the last decades, the average life expectancy of humans is increasing year-by-year. Although this is an excellent step forward for humanity, it has led older population to being more prone to illness and accidents such as falls. In this work a study is made on the existing literature in nonintrusive remote health monitoring systems, towards the design and implementation of an IoT system capable of identifying falls and monitor cardiac data. A Systematic Literature Review (SLR) method was considered, taking into account the existing literature on remote health monitoring systems, fall detection algorithms and IoT. The Design Science Research (DSR) methodology was used to seek to enhance technology and science knowledge about this dissertation’s topic, through the creation of an innovative artifact. The system includes a smart watch (LILYGO T-WATCH-2020-V2), programmable in C under Arduino IDE to detect falls and a photoplethysmography monitoring unit (PPG) based on a Onyx 9560 Bluetooth oximeter, capable of measuring the user’s blood oxygen percentage (SpO2) and heart rate, in real time. It also provides remote monitoring through a user-friendly website to visualize live data about the health status of the user. The system was tested in volunteers to show the effectiveness of remote health monitoring systems for the elderly population.Este documento apresenta o trabalho realizado na tese de Mestrado em Engenharia de Telecomunicações e Informática e descreve o desenvolvimento, implementação e validação de um Sistema de Monitorização Remota da Saúde para Idosos. Devido à crescente inovação tecnológica ao longo dos anos, a esperança média de vida dos seres humanos está a aumentar anualmente. Embora seja um excelente passo em frente para a humanidade, tem levado à população mais idosa a ser propensa a doenças e acidentes, tais como quedas. Neste trabalho, efectua-se um estudo sobre a literatura existente em sistemas não intrusivos de monitorização remota da saúde, com vista à concepção e implementação de um sistema IoT capaz de identificar quedas e monitorizar dados cardíacos. Foi concebida uma Revisão Sistemática da Literatura (SLR), tendo em conta literatura existente sobre sistemas de monitorização da saúde, algoritmos de detecção de quedas e IoT. A metodologia Design Science Research (DSR) foi utilizada para procurar melhorar os conhecimentos tecnológicos sobre o tema desta dissertação, através da criação de um artefacto inovador. O sistema inclui um relógio inteligente (LILYGO T-WATCH-2020-V2), programável em C sob a IDE Arduino para detectar quedas e um dispositivo de monitorização fotopletismográfico (PPG) baseada num oxímetro Onyx 9560 Bluetooth, capaz de medir a percentagem de oxigénio no sangue (SpO2) e o ritmo cardíaco. Fornece ainda monitorização remota através de um website para visualizar dados em direto sobre a saúde do utilizador. O sistema foi testado em voluntários para mostrar a eficácia dos sistemas de monitorização remota da saúde em idosos

Jatkuva-aikainen vitaalielintoimintojen monitorointi pienillä lapsilla käyttäen rinnalle asetettavaa sensoria

Tiivistelmä. Tausta: Hengitystaajuus, sydämen syketaajuus ja happisaturaatio (SpO₂) ovat verenpaineen lisäksi kliinisesti tärkeitä indikaattoreita vastasyntyneiden ja kriittisesti sairaiden potilaiden tilan arvioimisessa ja ennustamisessa. Kliinisessä käytössä ei kuitenkaan ole yhdellä sensorilla toteutettavaa jatkuva-aikaista monitorointimenetelmää, joka avulla samanaikainen vitaalielintoimintojen seuranta olisi helposti ja nopeasti aloitettavissa. Työn tarkoitus: Tutkimuksen tavoitteena oli testata ja validoida mittausmenetelmää, jolla mitataan rintakehältä ei-invasiivisesti hengitys- ja syketaajuutta sekä happisaturaatiota. Tässä työssä rintakehälle asetettiin kiihtyvyysanturin lisäksi optinen happisaturaatioanturi sekä testattiin mittausmenetelmän soveltuvuutta erityisesti pienten lasten monitorointiin. Toisen kaulalle sijoitettavan kolmiaksiaalisen kiihtyvyysanturin avulla voidaan estimoida myöhemmin pulssin kulkuaikasignaalia. Tutkimuksen avulla myös pilotoidaan osa laajemman kliinisen tutkimuksen mittausasetelmasta. Menetelmät: Tutkimuksen aineisto kerättiin kotioloissa tehdyillä mittauksilla. Tutkimusjoukko koostui seitsemästä perusterveestä pienestä lapsesta (keskiarvo 2,7 v ja keskihajonta 2,1 v). Mittauksissa kerättiin signaalia rintakehältä sekä optisella anturilla että kiihtyvyysanturilla. Lisäksi kiihtyvyyssignaalia mitattiin kaulalle sijoitettavalla kiihtyvyysanturilla. Raakasignaalin laatua ja mittausasetelman käytettävyyttä arvioitiin eri mittaustilanteissa ja signaalinkäsittelyllä mittaussignaaleista estimoitiin hengitys- ja syketaajuus. Pilotoitavaa tutkimusta varten rakennettiin myös käyttöliittymä, johon yhdistettiin videokuvan tallennus synkronoidusti mittaussignaalien kanssa sekä suunniteltiin mittausasetelma. Tulokset: Mittausmenetelmän todettiin soveltuvan pienten lasten monitorointiin ja mittaukset suoritettiin onnistuneesti eri ikäisiltä lapsilta. Signaalien laatu eri mittaustilanteissa oli hyvää signaalinkäsittelyä varten lähes kaikissa mittauksissa, jolloin niistä voitiin laskea hengitys- ja syketaajuus sekä happisaturaatio. Signaalinkäsittely vaatii kuitenkin lisää kehittämistä, jotta vitaalielintoiminnoista kertovat parametrit ovat tarkkoja ja suodattavat liikehdinnästä aiheutuvat artefaktat riittävän hyvin. Tässä tutkimuksessa saadut happisaturaatioarvot eivät myöskään olleet uskottavia. Mittausasetelma kokonaisuudessaan oli käytännöllisesti toteutettavissa pienten lasten jatkuva-aikaiseen monitorointiin kotioloissa. Johtopäätökset: Käytettyä menetelmää on aiemmin testattu onnistuneesti mitattaessa vitaalielintoimintoja aikuisilta (Myllylä et al., 2017). Tähän tutkimukseen perustuen hengitystä, sydämen sykettä ja happisaturaatiota on mahdollista mitata helposti myös pieniltä lapsilta, mutta mittausmenetelmän validoinnille on vielä tarvetta. Jatkotutkimuksessa mittausmenetelmää soveltuvuutta tutkitaan keskosten monitoroinnissa sekä tutkitaan vastasyntyneiden kotimonitoroinnin mahdollisuuksia sähköisiin terveydenhuoltopalveluihin yhdistettynä.Continuous monitoring of vital functions in small children using wearable sensor on the chest. Abstract. Background: Respiratory rate, heart rate, and oxygen saturation (SpO₂) are important parameters for vital functions providing important information to identify a critically ill patient. However, neither in clinical nor in home use, there is a single sensor available that can monitor all these vital signals simultaneously and reliable. Objective: The aim of the study was to test and validate a measurement method for measuring respiratory rate, heart rate and oxygen saturation non-invasively on the chest. In this work, in addition to the accelerometer, an optical oxygen saturation sensor was placed on the chest and the applicability of the measurement method was tested, especially for monitoring of small children. The second tri-axial accelerometer located on the neck can be used to estimate the pulse transit time signal. The study also piloted part of a broader clinical trial measurement setup. Methods: The research material was collected by home measurements. The study group consisted of seven healthy small children (mean age 2,7 y and standard deviation 2,1 y). Measurements were taken from the chest using both an optical sensor and an accelerometer. In addition, the accelerometer was placed on the neck. The quality of the raw signal and the usability of the measurement setup were evaluated in different measurement situations, and the respiratory rate, heart rate and oxygen saturation were estimated from the measurement signals by signal processing. The user interface was also designed for a pilot study, which will combine video recording in synchronization with measurement signals. Results: The measurement method was found to be suitable for monitoring small children and measurements were successfully performed on children of different ages. The raw signal quality in various measurement situations was acceptable in almost all cases so that respiratory and heart rates as well as SpO₂ could be calculated. However, signal processing requires further development in order to ensure sufficiently accurate data also during movements of children which seemed to cause great deal of artefacts. Also, the oxygen saturation values were not credible. The whole measurement setup was practically feasible for continuous monitoring of small children at home. Conclusion: Based on this study, respiration, heart rate, and SpO₂ can be easily measured, even from small children, but there is still a need for further validation. In the follow-up study, the measurement method will be used also to monitor premature infants in hospital, as well as to explore the potential of home monitoring of small children and newborns in combination with eHealth services

The Speed of Waves : Measuring the velocity of pressure pulse waves traveling through peripheral blood vessels

Worldwide, cardiovascular diseases (CVDs) are the number one cause of death. Therefore, there is a strong and urgent need for an easy and quick prognostic indicator of this disease to support early diagnosis. The gold standard for determining arterial stiffness is measuring the pulse wave velocity (PWV), which is the speed of the pressure pulse traveling through the moving blood. The goal of this Ph.D. study was to develop and validate a non-invasive, photoplethysmography (PPG)-based device for peripheral measurement of the PWV on the finger. To this aim a novel sensor, called “Multi Photodiode Array” (‘MPA’), was designed for peripheral, non-invasive PWV measurements. Next, the MPA was shown to deliver reliable and accurate PWV measurements with a deviation below 3% within clinically relevant ranges. During the course of the research it was observed that the MPA positioning on the finger could strongly affect the quality of the PWV measurements. Therefore, an explorative study was conducted to find the optimal use condition of the MPA. The final clinical study showed that the MPA could be placed easily, rapidly, and consistently, irrespective of the volunteer whose PWV was measured, and delivered reliable and repeatable results. Overall, the results in this thesis suggest that the novel PPG-based MPA allows accurate and reliable PWV measurements within clinically relevant ranges. In the future, the MPA may substantially simplify PWV measurements and enable long-term monitoring of vascular health, which will contribute to improving prevention, diagnosis and treatment of CVD