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Cilj ovoga rada je implementirati programsku podršku sustava za površinsku elektromiografiju visoke prostorne razlučivosti. Programska potpora podrazumijeva implementaciju SPI i Wi-Fi komunikacije. U radu su ostvarene navedene komunikacije te je stvoren funkcionalni sustav. Sustav prikuplja podatke s elektroda te ih pomoću SPI-ja šalje do mikrokontrolera EPS32. Mikrokontroler šalje podatka pomoću Wi-Fi-ja do udaljenog poslužitelja gdje se podatci mogu dalje obrađivati, prikazivati i analizirati. This paper aims to implement software support for the High-Density Surface Electromyography system. Software support includes the implementation of SPI and Wi-Fi communication. Mentioned communications were realized in the paper, and a functional system was created. The system collects data from electrodes and sends them to the ESP32 microcontroller using SPI. The microcontroller sends data via Wi Fi to a server where the data can be further processed, displayed and analyzed.

Elektrodiagram eller EKG används inom sjukvården för att mäta hjärtats elektriska aktivitet med hjälp av flera elektroder som placeras ut på kroppen. Från mätningarna kan indikationer på hjärtsjukdomar och störningar i hjärtrytm upptäckas och sedan behandlas. Hjärt- och kärl-sjukdomar är den vanligaste dödsorsaken i Sverige och behovet av EKG undersökningar är stort. Vanligtvis är EKG-apparaterna stora, otympliga och begränsade till sjukhus då de är komplicerade och dyra. Linköpings universitets forskningsgrupp tillsammans med flera examensarbeten har då tagit fram en prototyp på en kompakt och portabel EKG. Den portabla EKG-apparaten kopplas med en sele som är integrerad med elektroder och ska brukas av främst kvinnor, då utbudet av användarvänliga EKG:s till kvinnor är litet. Den tidigare portabla EKG:en är uppbyggd av två moduler, EKG-modulen och Nordic Thingy52. EKG-modulen konstruerad på ett specialanpassat kretskort som utför den faktiska mätningen av elektroderna och uträkningar. Den är sedan ihopkopplad med Thingy52 som ansvarar för den trådlösa kommunikationen till andra enheter via Bluetooth Low Energy eller BLE som det också kallas. BLE-modulen som innefattade Thingy52 och den modifierade källkoden från tidigare arbeten, klarade av viss trådlös kommunikation men ansågs vara förlångsam och klarade inte av kontinuerlig dataöverföring. Från de tidigare arbetena uppkom då frågeställningar om det var möjligt att vidareutveckla den tidigare BLE-modulen genom att förbättra dataöverföring och införa fler funktioner. De mest väsentliga önskemål var att optimera modulens dataöverföring till att bli kontinuerlig, införa funktionalitet för att spara mätvärden som en typ av backup och introducera ett enklare digitalt filter för att filtrera bort brus och störningar på mätvärdena. Utöver detta skulle även ett kompaktare och mindre kretskort till BLE-modulen tas fram som skulle ersätta Thingy52. Projektet började med att införskaffa kunskap och förståelse om hur befintliga och tillkommande funktioner samt tjänster fungerar samt hur de ska implementeras. Val om vilka komponenter och utvecklingsmiljöer som skulle användas under projektet fastställdes. Valen resulterade i att fortsätta med tidigare System-on-chip, SoC nRF52832 från Nordic Semiconductor som Thingy52 är utformad runt. Detta ledde till att befintliga utvecklingskort kunde användas och kretsschema från Thingy52 kunde återanvändas till det nya kretsschemat. Innan det eget skapade kretskortet kunde beställas och testas behövdes verifiering av att den valda SoC klarade av kontinuerlig dataöverföring. Detta kunde utföras på utvecklingskort nRF52 SDK med samma typ av SoC. Verifieringen av dataöverföringen var mer tidskrävande än vad som hade räknats med och tyvärr blev det inte tid att beställa kretskortet och kunde inte testas i praktiken. Ett kretsschema utfördes ändå som har mindre dimensioner än Thingy52 och innehåller de önskade delarna. Under utveckling av BLE-funktionen valdes det att använda Nordic:s nya utvecklingsmiljö som förenklade programmering av avancerade funktioner, till exempel BLE. Valet av att byta utvecklingsmiljö resulterade dock i att tidigare programmeringskod som hanterade konfigurering och dataöverföring med EKG-modulen, behövdes konverteras om till ett nytt operativsystem efter att Nordic bytt till operativsystemet Zypher. Detta gav i följd att funktioner och bibliotek inte stödes eller inte fanns. Efter detta flyttades fokuset till att implementera och integrera lagringsfunktionen med BLE- och EKG-funktionerna. Multitrådning infördes för att kunna utföra och optimera BLE-modulens funktioner. Tidsbrist gjorde att endast platshållare för framtida implementering av digitala filter kunde utföras. Utifrån de testresultaten över BLE-modulen är det även svårt att garantera att SoC hinner utföra filtrering av mätdata under det redan begränsade tidsintervallet. Efter en del problem och många tester resulterade examensarbetet slutligen i ett kompakt kretsschema som skulle kunna ersätta Thingy52. En BLE-modul som kan utföra dataöverföring med viss kontinuerlighet och samtidigt lagra mätdata till ett SD-kort utan att påverka kommunikationen med EKG-modulen eller användargränssnittet. Slutprodukten har även många möjligheter att utökas i framtida arbeten. Electrocardiography or ECG is used in healthcare to measure the electrical activity of the heart using several electrodes that are placed on the body. From the measurements, indications of heart diseases and heart rhythm disorders can be detected and then treated. Cardiovascular disease is the most common cause of death in Sweden and the need for ECG examinations is great. Usually the ECG devices are large, awkward, and limited to hospitals as they are complicated and expensive. Linköping University's research group together with several bachelor thesis projects has developed a prototype of a compact and portable ECG. The portable ECG device is connected to a bra that is integrated with electrodes and should be used mainly by women, as the range of user-friendly ECGs for women is small. The previously portable ECG is made up of two modules, the ECG module, and the Nordic Thingy52. The ECG module is designed on a specially adapted circuit board that performs the actual measurement of the electrodes and calculations. It is then paired with Thingy52 which is responsible for the wireless communication to other devices via Bluetooth Low Energy or BLE as it is also called. The BLE module, which included Thingy52 and the modified source code from previous work, managed some wireless communication but was considered too slow and could not handle continuous data transfer. From the previous work questions arose as to whether it was possible to further develop the previous BLE module by improving data transfer and introducing more features. The most desired features were to optimize the module's data transfer to become continuous, implement functionality to save measured values as a type of backup and implement a simple digital filter to filter out noise and disturbances of the measured values. In addition to this, a more compact and smaller circuit board for the BLE module would also be developed that would replace the Thingy52. The project began with acquiring knowledge and understanding of how existing and additional functions or services work and how they should be implemented. Choices about which components and development environments would be used during the project were determined. The choice resulted in continuing with the previous System-on-chip, SoC nRF52832 from Nordic Semiconductor around which Thingy52 is designed. As a result, existing development boards could be used and the circuit diagram from Thingy52 could be reused for the new circuit diagram. Before the self-created circuit board could be ordered and tested, verification was needed to determine that the selected SoC was capable of continuous data transfer. This could be done on development card nRF52 SDK with the same type of SoC. The verification of the data transfer was more time consuming than had been expected and unfortunately there was no time to order the circuit board and therefore could not be tested in practice. A circuit diagram was nevertheless performed which has smaller dimensions than Thingy52 and contains the desired parts. During the development of the BLE function, it was chosen to use Nordic's new development environment as it simplified programming of advanced functions, like BLE. The choice to change the development environment, however, resulted in the previous programming code, which handled configuration and data transfer with the ECG module, having to be converted to a new operating system after Nordic switched to the Zypher operating system. As a result, functions and libraries were not supported or did not exist. After this, the focus shifted to implementing and integrating the storage function with the BLE and ECG functions. The multithreading tool was introduced to perform and optimize the functions of the BLE module. Lack of time meant that only placeholders for future implementation of digital filters could be performed. Based on the test results over the BLE module, it is also difficult to guarantee that the SoC has time to perform filtering of measurement data during the already limited time interval. After some problems and many tests, the bachelor thesis project finally resulted in a compact circuit that could replace Thingy52. Also, a BLE module that can perform data transfer with some continuity and at the same time store measurement data to a SD card without affecting the communication with the ECG module or the user interface. The end product also has many opportunities to be expanded in future work.

U ovom radu obrađene su teme snimanja elektromiografskih signala i problemi koji se pojavljuju prilikom snimanja površinske elektromiografije. Tehnikom snimanja površinske elektromiografije visoke prostorne razlučivosti moguće je riješiti problem ispravnog pozicioniranja elektroda i ponovljivosti mjerenja. Kao rezultat rada implementiran je 16 kanalni sustav. Napravljena je analiza analognih sučelja za mjerenje biopotencijala proizvođača Texas Instruments. Na temelju provedene analize odabrano je analogno sučelje ADS1298. Za implementaciju 16 kanalnog sustava povezana su dva ADS1298 kojima preko SPI protokola upravlja mikrokontroler ESP32. Projektirana je tiskana pločica na kojoj su dva ADS1298 i potrebno sklopovlje, a preko konektora se spaja na tiskanu pločicu s ESP32. Za razvijeni sustav napisana je ispitna programska podrška, tehnička dokumentacija i upute za korištenje. This paper deals with the topics of electromyographic signal recording and problems that appear when recording surface electromyography. With the technique of high density surface electromyography, it is possible to solve the problem of correct electrode positioning and repeatability of measurements. As a result of the work, a 16-channel system was implemented. An analysis of analog front - end ICs from Texas Instruments for measuring the biopotential was made. Based on the performed analysis, the analog front - end ADS1298 was selected. For the implementation of the 16-channel system, two ADS1298s are connected, which are controlled by the ESP32 microcontroller via the SPI protocol. A PCB with two ADS1298 and the additional hardware is designed, and it is connected to the PCB with ESP32 via a connectors. Test software, technical documentation and instructions for use have been written for the developed system.

Projektet tar sin start i den intressanta fasen testning och verifiering. En prototyp har påbörjats för ett portabelt EKG tillsammans med Linköpings universitet och ett tidigare examensarbete. Prototypens elektriska egenskaper behöver nu genomgå test och verifiering. Samt undersöka om kretskortet kan ha blivit fel designat. Målsättningen för produkten är att den ska kunna krympa avståndet mellan mätpunkterna i förhållande till ett 12 avlednings-EKG. En problematik för arbetet är att undersöka vilka alternativa placeringar eller konfigurationer av Wilson Central Terminal som kan göras på enbart överkroppen. En testplattform grundad på enkortsdatorn Raspberry Pi utformades för att säkerställning av systemets funktionalitet kunde utföras med en känd signal. Efter säkerställningen gjordes tester med elektroder på person. Testplattformen fungerade väl och kunde ge en bra bild över produktens kapacitet och begränsningar. Kretskortet är felkopplat i någon mening samt att systemet begränsar frekvensomfånget så att inte alla nödvändiga frekvenser upptas för en korrekt återspegling av hjärtats aktivitet. Produkten fungerar bra men har en del funktioner kvar att implementera innan den kan tas i allmänt bruk. Att dubbla bandbredden för frekvenser skulle innebära att hjärtfel inom de området skulle upptäckas av systemet. En av elektroderna har anslutits till fel kanalingång på A/D-omvandlaren för att helt kunna kopiera och komprimera en normal mätning av EKG. The project takes it start at the interesting phase testing and verification. A prototype has been started for developing of a portable ECG in cooperation between Linköpings university and an earlier bachelor thesis. The prototypes electrical properties need to be tested and verified. The PCB also needs an examination to see if it has been incorrectly designed. The objective for this product is to minimize the distance between the measuring points relative to a 12-lead ECG. A challenging task is to examine what alternative placements or configurations there is of Wilson Central Terminal which can only be done on the upper body. A test platform based on the single card computer Raspberry PI has been developed to ensure the systems functionality by sending a known signal into the system. Next phase after the verification was to undergo and investigate the system behavior when the electrodes is placed on a test person. The test platform worked well and was able to put light on both the abilities and constraints. It turned out that in some meaning the PCB is not optimally designed. The total bandwidth for the system is limited and cannot fully represent all frequencies that is needed to cover extreme cases and give an exact health check on the heart. The instrument is now able to pick up the electric activities with aid from the loose electrodes, that also has been used under the verification. There still is a small amount of noise left on the signal. Before the instrument can be launched to commercial use there remain a few functions to implement. One thing is to double the bandwidth, it should solve the difficulty to detect the higher frequency. It is not necessary, but to completely shrink and copy the original pattern from a larger EKG-measurement the PCB design must be remade. The results from the new pattern appear to be good enough but must be verified from medical view.

There is a large number of biosignals that can be obtained from the human body. Repositories of biosignals are used for researchers in many studies as datasets. Datasets with clinical and personal information have many regulations and they are not accessible to everyone. Platforms with acquisition, recording and visualization of data are currently used in homecare systems for monitoring patients in an effcient way. Distant monitoring allows a good and prompt communication between patients and physicians. This work describes the design and development of a platform at hardware and software level for recording, storage, visualization and analysis of biosignals on the cloud. For the platform, IoT and Cloud Computing resources were used. Open-source and free software are considered for an easy and flexible enlargement of the system.

U okviru rada razvijen je sklop za prikupljanje bioelektričnih signala temeljen na ADS129x integriranom sklopu. Tiskana pločica omogućuje primjenu ADS1298 i ADS1299 sklopova, koji su pin-kompatibilni i razlikuju se u nekim specifičnim tehničkim karakteristikama, ciljnim primjenama i cijeni. Sustav je upravljan mikrokontroleorm STM32F407, a omogućava pohranu podataka na SD karticu te komunikaciju putem Wi-Fi i drugih radijskih sučelja. Proširenje sustava moguće je korištenjem I2C, SPI, USART i USB komunikacijskih sučelja. Sustav predstavlja fleksibilnu, kompaktnu i prenosivu platformu koja može poslužiti za daljnji razvoj i istraživanje u području biomedicinskih primjena. In this thesis a device for acquisition of bioelectric signals was developed, based on ADS129x integrated circuit. Printed circuit board is suitable to accomodate both ADS1298 and ADS1299 variants, which are pin-compatible and they differ in some specific technical characteristics, target applications, and price. The system is controlled by STM32F407 microcontroller, it enables data storage on SD card, and communcation via Wi-Fi and other radio protocols. System expansion is available through I2C, SPI, USART, and USB interfaces. System represents a flexible, compact, and mobile platform that can be used for further research and development in the field of biomedical applications.

A 12-lead ECG data acquisition system based on ADS1298 is presented in this paper. ADS1298 is a latest 16-channel 24-bit Analog to Digital Converter (ADC) made in TI Company, which has the characters of high-precision, low power and low noise, with the internal integration of the input multiplexers, analog low-pass filter, and digital filter, etc. Combined with the high-speed low-power chip M051 as MCU, it can achieve the standard 12-lead simultaneous ECG acquisition. ECG data can also be transmitted to an upper host PC though nRF24LE1 MCU. This system greatly compact the circuit and reduce the power cost, as well as implement the wireless transmission. It has laid the foundation for the future high-accuracy portable ECG instrument.

Se presenta un sistema compuesto por hardware de adquisición y software de soporte para la medición de biopotenciales en tiempo real desde una PC. El equipo cuenta con 8 canales diferenciales acoplados en continua, muestreados con convertidores analógico-digitales sigma-delta de 24 bits, con ganancia y tasa de muestreo configurables. La resolución del dispositivo está dada por el piso de ruido del sistema que es inferior a 2 µVrms en un ancho de banda de (0,05-100) Hz. Para medidas en un ancho de banda de 1 kHz el piso de ruido resulta menor a 3 µVrms. El coeficiente de rechazo de modo común es de 96 dB, y para lograr medidas de mayor calidad se utilizan electrodos activos y un circuito independiente para reducir la tensión de modo común, lo que posibilita utilizar topologías de medición no diferenciales. La transmisión de datos y de energía para todo el sistema se realiza a través del bus USB. El equipo cuenta con una barrera de aislamiento compatible con normas internacionales de seguridad eléctrica para equipamiento médico. Se relevó la respuesta en frecuencia y se comprobó que cumple con requisitos para dispositivos de electrocardiografía. Se adquirieron distintas señales de biopotenciales para verificar el funcionamiento del equipo y demostrar el uso del software. A biopotential measurement system composed of acquisition hardware and software capable of relaying real-time signals to a PC is presented. The device has 8 DC coupled differential channels sampled by 24 bits sigma-delta analog to digital converters with programmable gain and sampling frequency. The noise floor of the device determines its resolution, and it is less than 2 µVrms in a bandwidth of (0.05-100) Hz. Measurements up to 1 kHz can be carried out with a noise voltage less than 3 µVrms. The common mode rejection ratio is 96 dB. To achieve high-quality measurements active electrodes are used along with a common mode voltage reduction circuit allowing single-ended measurement topologies. A USB connection serves both as data channel and power source. The device includes an isolation barrier in agreement with international standards for the electrical safety of medical equipment. Its frequency response was measured and compared with accepted standards for electrocardiographic devices, and various biopotential measurements were carried out in order to test both hardware and software. É apresentado um sistema composto de hardware de aquisição e software de suporte para a medição de biopotenciais em tempo real a partir de um PC. O aparelho tem 8 canais diferenciais acopladas em contínuo, amostrados com conversores analógico-digital sigma-delta 24 bits. com o ganho e taxa de amostragem configurável. A resolução do dispositivo é determinado pelo nível de ruído do sistema é menos 2 µVrms uma largura de banda (0,05-100) Hz. Para medições em uma largura de banda de 1 kHz o piso de ruído é inferior a 3 µVrms. A razão de rejeição de modo comum é 96 dB, e para se obter medidas de qualidade superior é usado eléctrodos activos e um circuito separado para reduzir a tensão de modo comum, tornando-se possível a utilização de topologias de medição não diferenciais. A transmissão de dados e energia para todo o sistema é feito através do barramento USB. A equipe tem uma barreira de isolamento compatível com as normas de segurança elétrica internacionais para equipamentos médicos. Foi revelada a resposta em frequência e está em conformidade com os requisitos para dispositivos de eletrocardiografia. Se Obteveram diferentes sinais de biopotenciais para vereficar o funcionamento equipamento e demonstrar a utilização do software.

Se presenta un sistema compuesto por hardware de adquisición y software de soporte para la medición de biopotenciales en tiempo real desde una PC. El equipo cuenta con 8 canales diferenciales acoplados en continua, muestreados con convertidores analógico-digitales sigma-delta de 24 bits, con ganancia y tasa de muestreo configurables. La resolución del dispositivo está dada por el piso de ruido del sistema que es inferior a 2 µVrms en un ancho de banda de (0.05-100) Hz. Para medidas en un ancho de banda de 1 kHz el piso de ruido resulta menor a 3 µVrms. El coeficiente de rechazo de modo común es de 96 dB, y para lograr medidas de mayor calidad se utilizan electrodos activos y un circuito independiente para reducir la tensión de modo común, lo que posibilita utilizar topologías de medición no diferenciales. La transmisión de datos y de energía para todo el sistema se realiza a través del bus USB. El equipo cuenta con una barrera de aislamiento compatible con normas internacionales de seguridad eléctrica para equipamiento médico. Se relevó la respuesta en frecuencia y se comprobó que cumple con requisitos para dispositivos de electrocardiografía. Se adquirieron distintas señales de biopotenciales para verificar el funcionamiento del equipo y demostrar el uso del software. A biopotential measurement system composed of acquisition hardware and software capable of relaying real-time signals to a PC is presented. The device has 8 DC coupled differential channels sampled by 24 bits sigma-delta analog to digital converters with programmable gain and sampling frequency. The noise floor of the device determines its resolution, and it is less than 2 µVrms in a bandwidth of (0.05-100) Hz. Measurements up to 1 kHz can be carried out with a noise voltage less than 3 µVrms. The common mode rejection ratio is 96 dB. To achieve high-quality measurements active electrodes are used along with a common mode voltage reduction circuit allowing single-ended measurement topologies. A USB connection serves both as data channel and power source. The device includes an isolation barrier in agreement with international standards for the electrical safety of medical equipment. Its frequency response was measured and compared with accepted standards for electrocardiographic devices, and various biopotential measurements were carried out in order to test both hardware and software. é apresentado um sistema composto de hardware de aquisição e software de suporte para a medição de biopotenciais em tempo real a partir de um PC. O aparelho tem 8 canais diferenciais acopladas em contínuo, amostrados com conversores analógico-digital sigma-delta 24 bits. com o ganho e taxa de amostragem configurável. A resolução do dispositivo é determinado pelo nível de ruído do sistema é menos 2 μVrms uma largura de banda (0,05-100) Hz. Para medições em uma largura de banda de 1 kHz o piso de ruído é inferior a 3 μVrms. A razão de rejeição de modo comum é 96 dB, e para se obter medidas de qualidade superior é usado eléctrodos activos e um circuito separado para reduzir a tensão de modo comum, tornando-se possível a utilização de topologias de medição não diferenciais. A transmissão de dados e energia para todo o sistema é feito através do barramento USB. A equipe tem uma barreira de isolamento compatível com as normas de segurança elétrica internacionais para equipamentos médicos. Foi revelada a resposta em frequência e está em conformidade com os requisitos para dispositivos de eletrocardiografia. Se Obteveram diferentes sinais de biopotenciais para vereficar o funcionamento equipamento e demonstrar a utilização do software. Fil: Guerrero, Federico Nicolás. Universidad Nacional de la Plata. Facultad de Ingeniería. Departamento de Electrotecnia. Laboratorio de Electrónica Industrial, Control e Instrumentación; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Haberman, Marcelo Alejandro. Universidad Nacional de la Plata. Facultad de Ingeniería. Departamento de Electrotecnia. Laboratorio de Electrónica Industrial, Control e Instrumentación; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Spinelli, Enrique Mario. Universidad Nacional de la Plata. Facultad de Ingeniería. Departamento de Electrotecnia. Laboratorio de Electrónica Industrial, Control e Instrumentación; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina