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La thèse s’inscrit dans le cadre du projet de recherche collaborative VEADISTA (Veille à distance et alerte intelligente) qui repose sur la conception d’une technologie ergonomique à bas coût. L’objectif de cette thèse est de concevoir et de réaliser des capteurs de température et de pression imprimés sur support flexible pour des applications biomédicales. Ils doivent être adaptés à une intégration sur un transpondeur passif télé-alimenté, conformables pour s’adapter au bras du patient, bas coût et permettant un transfert technologique vers l’industrie.Des prototypes de tests ont été réalisés dans le but d’identifier la topologie et la couche active les plus prometteuses pour la réalisation des capteurs de température en tout imprimé sur support souple. A l’issue de cette étude préliminaire, une thermorésistance à base d’encre d’argent a été réalisée par jet d’encre sur un substrat flexible. La caractérisation de ces capteurs a permis d’évaluer leur sensibilité et d’attester de leur bonne linéarité.Des tests préliminaires sur des capteurs commerciaux ont ensuite été effectués pour démontrer qu’il était possible de détecter le rythme cardiaque avec un capteur de pression. A la suite de cette étude, des capteurs de pression sur support souple ont été fabriqués en utilisant la technologie jet d’encre. Ces capteurs ont été caractérisés électriquement sous contrainte mécanique contrôlée. Pour aboutir à ces résultats, de nombreux développements technologiques ont été réalisés autour de la technique d’impression par jet d’encre. La maîtrise du triptyque encre-tête d’impression-substrat est en effet indispensable pour l’obtention de motifs de qualité. / This thesis is a part of the collaborative research project VEADISTA (Remote monitoring of vital parameters and smart alerts) based on the conception of an ergonomic technology at low-cost.The objective of this thesis is to design and to realize printed temperature and pressure sensors on flexible support for biomedical applications. Subsequent to this, these sensors must be suitable to an integration on a passive transponder remotely powered, conformable to fit the patient's arm, low cost and allowing a technological transfer towards industry.Prototype tests were realized in order to identify the most promising topology and active layer to achieve printed temperature sensors on flexible support. At the end of this preliminary study, a RTD based on a silver ink was performed by inkjet on a flexible substrate (Kapton). The characterization of these sensors allowed to assess their sensitivity and to attest to their good linearity.The preliminary tests on commercial sensors were then made to demonstrate that it was possible to detect the heart rate with a pressure sensor. Following this study, pressure sensors were manufactured on flexible support using inkjet technology. These sensors were electrically characterized under controlled mechanical constraint. To achieve these results, many technological developments were realized around the inkjet printing technique. The mastery of the ink – inkjet head – substrate interaction is indeed essential for obtaining good printed quality and functional sensors.

Στον τομέα της κινητικής αποκατάστασης, η έννοια της βιοανάδρασης για τη βελτίωση του ταλάντευσης της στάσης του ανθρώπινου σώματος και του ελέγχου της ισορροπίας είναι αρκετά διαδεδομένη. Στις περισσότερες περιπτώσεις, το υποκείμενο προσπαθεί να ελέγξει τη θέση του με μια οπτική, προφορική ή αφής ανατροφοδότηση που παρέχεται από ένα ηλεκτρονικό σύστημα ή έναν νοσοκομειακό γιατρό. Πρόσφατες μελέτες αφορούν ασθενείς με κάποια νευρολογική ασθένεια που ελάμβαναν την οπτική ανατροφοδότηση στεκόμενοι σε μια δυναμοπλατφόρμα, ώστε να ελέγχουν την θέση του σημείου κεντρικής τους πίεσης (CoP). Στην έρευνά μας, καταγράφουμε τη κατανομή πίεσης κάτω από τα πόδια του υποκειμένου και παρέχουμε τις σχετικές ακουστικές πληροφορίες βιοανάδρασης (ABF) στην κατεύθυνση της βελτίωσης της ισορροπίας στάσης του. Με την παροχή αυτών των πρόσθετων ακουστικών πληροφοριών, στόχος μας είναι να διευκολύνουμε τη διαδικασία αντιστάθμησης της ελλείπουσας ή ανεπαρκούς αισθητήριας πληροφορίας από το κεντρικό νευρικό σύστημα (CNS). Έχουμε αναπτύξει και σε προκαταρκτικό στάδιο δοκιμάσει ένα σύστημα ακουστικής βιοανάδρασης βασιζόμενο σε μεσοσόλες με αισθητήρες πίεσης. Ο χρησιμοποιούμενος αλγόριθμος ABF έχει την ίδια βάση με αυτον που εφαρμόζεται σε ένα πρωτοτύπο ABF σύστημα, ήδη αναπτύγμενο και δοκιμασμένο, το οποίο ελέγχει τις μετακινήσεις επιτάχυνσης του σώματος. Οι μετρήσεις των τιμών πίεσης στα πόδια γίνονται μέσω ενός ζευγαριού εύκαμπτων μεσοσολών με 24 ειδικούς ενσωματωμένους αισθητήρες πίεζο-αντίστασης που περικλύονται σε κυτταρική δομή γεμάτη υγρό (Paromed). Η εφαρμογή ελέγχου αναπτύχθηκε σε περιβάλλον LabView και επιτρέπει τη συλλογή δεδομένων πίεσης σε 100Hz και την επεξεργασία αυτών σε πραγματικό χρόνο για τον υπολογισμό μιας εκτίμησης της τιμής του στιγμιαίου CoP. Η συμπεριφορά ταλάντευσης του CoP στα δυο επίπεδα, εμπρόσθια-οπίσθια AP και διάμεσα-πλευρικά ML, αποτυπώνεται σε ένα στερεοφωνικό ακουστικό σήμα που αλλάζει στο εύρος, τη συχνότητα και την ισορροπία L/R και μέσω των ακουστικών παρέχεται στο υποκείμενο. Το πειραματικό μας πρωτόκολλο περιέλαβε μια σειρά μετρήσεων με υγιείς εθελοντές εκτελώντας συγκεκριμένους στατικούς στόχους, με και χωρίς παρεχόμενο ABF. Κατά τη διάρκεια αυτών των στόχων προσπαθήσαμε να εξομοιώσουμε τις συνθήκες όπου η αισθητήρια πληροφορία είναι ελλείπουσα ή ανεπαρκής. Προκαταρκτικά αποτελέσματα στην ML κατεύθυνση, έδειξαν οτι με την ύπαρξη του ABF το ανθρώπινο σώμα ταλαντεύθηκε λιγότερο, γεγονός ενδεικτικό του ότι αυτό το νέο-αναπτυγμένο σύστημα βιοανάδρασης βασιζόμενο στις πίεζο-μεσοσόλες μπορεί να χρησιμοποιηθεί για να βελτιώσει την ισορροπία. Περισσότερα πειράματα και αναλυτική στατιστική ανάλυση πρέπει να ακολουθήσουν ώστε να γίνει κατανοητή η επιρροή αυτού του ABF στην ισορροπία του ανθρώπινου σώματος. / In the area of motor rehabilitation, the concept of biofeedback for improving postural sway and balance control is quite common. In most cases, the subject tries to control his position by a visual, oral or tactile feedback provided by an electronic system or a clinician. Recent studies involved patients with neurological disease that were receiving visual feedback as were standing in a force plate, for the monitoring of their centre of pressure (CoP) position. In our research, we record the pressure distribution beneath the subject's feet and provide related audio biofeedback (ABF) info in the direction of improving posture balance. By providing this extra audio information to the subject our aim is to facilitate the compensation process of the missing or inadequate sensory information by its central nervous system (CNS). We have developed and preliminary validated an insole pressure sensor-based, ABF system. The ABF concept followed is the same with the one applied in a prototype ABF system, already developed and validated, which monitors trunk acceleration movements. Foot pressure values were acquired through a pair of flexible insoles with 24 embedded discrete piezo-resistive sensors contained in a fluid-filled cell (Paromed). The control application was developed in LabView environment and permits pressure data collection in 100Hz and real-time processing for the calculation of an estimated value of the instant CoP. Swaying CoP behaviour in both AP and ML planes is mapped in a stereo audio signal changing in amplitude, frequency and L/R balance, which through the earphones is provided to the subject. Our experimental protocol involved a series of measurements with normal subjects performing specific static tasks, with and without ABF provided. During these tasks we tried to simulate conditions of missing or inadequate sensory information. Preliminary results about ML direction, shown that when ABF was provided the subject swayed less, suggesting that this new-developed biofeedback pressure-sensor insole-based system can be used to improve balance. More experiments and appropriate statistical analysis has to be done so as to understand the influence of this ABF on subject’ s balance.

In der vorliegenden Arbeit wurde eine neue Klasse von implantierbaren biochemischen Sensoren bezüglich ihrer Sensitivität im physiologisch relevanten pH- (pH 7,4) sowie Glukose-Konzentrationsbereich (2 - 20 mM) entwickelt und untersucht. Die Glukose-sensitiven Hydrogele basieren auf der Bindung von 5-fach-Zuckern an Boronsäuregruppen, die in einem Acrylamid-basierten Hydrogel mit N,N′-Methylenbisacrylamid (BIS) als Vernetzter (AAm/APB/BIS, 80/20/0,75 mol%) verankert sind. Weiterhin konnten pH-sensitive Hydrogele auf Basis von 2-(Dimethylamino)ethyl Methacrylate (DMAEMA), Hydroxypropyl-methacrylat (HPMA) sowie Tetraethyleneglycol dimethacrylate (TEGDMA) als Vernetzter in unterschiedlichen Zusammensetzungen und Geometrien untersucht werden. Die verwendeten Hydrogele wurden hinsichtlich der Diffusionsprozesse sowie ihrer Quellkinetik charakterisiert, um deren Sensitivität, Selektivität, Reproduzierbarkeit und Ansprechzeit gegenüber den physiologischen Parametern (pH, pCO2, Glukose) zu verbessern. Die aufgebauten pCO2-Sensoren zeigten vielversprechende Ansprechzeiten von wenigen Minuten. Die Glukose und pH-Sensoren wiesen im physiologischen Medium (PBS) deutlich höhere Ansprechzeiten von mehreren Stunden auf. Die Kombination von piezoresistiven Drucksensoren mit Stimuli-sensitiven Hydrogelen bietet nicht nur eine große Vielfalt bezüglich der zu detektierenden Analyten, sondern ermöglicht auch miniaturisierte und implantierbare Sensoren für die kontinuierliche Erfassung von physiologischen Parametern. So war die Verkapselung zum Schutz und zugleich zur Gewährleistung der Biokompatibilität und ohne Beeinträchtigung der Funktionalität und Flexibilität der elektronischen Bauteile das Ziel. Dazu wurden die Sensoren mit dem Polymer Parylene C eingehaust, dass zusätzlich eine Polyethylenglykolschicht enthielt. Hierfür wurden Blockcopolymere mittels Ringöffnungspolymerisation synthetisiert, die Polyaminosäuren als Linkermoleküle und PEG zur gezielten Funktionalisierung enthalten. Nach kovalenter Anbindung an die inerte Parylene C-Oberfläche zeigten sich deutlich veränderte Oberflächeneigenschaften und eine verbesserte Zellkompatibilität und Hämokompatibilität. Zudem wurde der sogenannte Tarnkappeneffekt von PEG-Ketten, die sich in der Schicht nach außen ausrichten, festgestellt. Damit wurde Adsorption von Proteinen (Fibronektin, Fibrinogen), die in Entzündungsreaktionen, der Zelladhäsion sowie der Blutgerinnung maßgebend sind, deutlich verringert. / In this work a new class of implantable biochemical sensors with a high sensitivity at physiological pH (pH 7,4) and glucose (2 – 20 mM) ranges were developed and tested. The glucose sensitive hydrogel was made of acrylamide and N,N′-methylene-bis(acrylamide) as a crosslinker (AAm/APB/BIS, 80/20/0,75 mol%). The swelling mechanism was based on the reversible interaction of sugar molecules and the boronic acid groups in the hydrogel. Also a pH sensitive hydrogel made of 2-(dimethylamino) ethyl methacrylate (DMAEMA), hydroxypropyl-methacrylat (HPMA) and the crosslinker tetraethylene glycol dimethacrylate (TEGDMA) with different molar ratios and geometries was characterized. The swelling kinetics as well as the diffusion processes of different hydrogels were studied to advance sensitivity, selectivity, reproducibility and response time with respect to physiological parameters (pH, pCO2, glucose). pCO2 sensors showed promising short response times of about 4 min whereas glucose and pH sensors displayed longer response times of several hours in phosphate-buffered saline solution. The combination of piezoresistive pressure sensors and stimuli-sensitive hydrogels enables a great diversity of detecting analytes as well as miniaturized and implantable sensors for continuous measuring of physiological parameters. However, to implant the sensors an encapsulation strategy is needed that secures the electronics as well as ensures the biocompatibility without loss of functionality and flexibility. For this, the devices were coated with the polymer parylene C and an additional layer of blockcopolymers composed of polyaminoacid (PAA) and polyethyleneglycol (PEG) blocks synthesized via ring-opening polymerization. The functionalization units are carried out by the PEG blocks whereas the PAA blocks perform as linker molecules onto the activated parylene C surface. After covalent coupling of blockcopolymers to the inert polymer the surface characteristics changed and hence the cell and blood compatibility was improved. Furthermore the stealth effect of the outwards PEG chains was utilized to reduce the adsorption of proteins like fibronectin or fibrinogen. These proteins play a major role in inflammatory processes, cell adhesion and blood coagulation. The results gave proof that the encapsulation leads to decisively reduced physiological reactions.

In der vorliegenden Arbeit wurde eine neue Klasse von implantierbaren biochemischen Sensoren bezüglich ihrer Sensitivität im physiologisch relevanten pH- (pH 7,4) sowie Glukose-Konzentrationsbereich (2 - 20 mM) entwickelt und untersucht. Die Glukose-sensitiven Hydrogele basieren auf der Bindung von 5-fach-Zuckern an Boronsäuregruppen, die in einem Acrylamid-basierten Hydrogel mit N,N′-Methylenbisacrylamid (BIS) als Vernetzter (AAm/APB/BIS, 80/20/0,75 mol%) verankert sind. Weiterhin konnten pH-sensitive Hydrogele auf Basis von 2-(Dimethylamino)ethyl Methacrylate (DMAEMA), Hydroxypropyl-methacrylat (HPMA) sowie Tetraethyleneglycol dimethacrylate (TEGDMA) als Vernetzter in unterschiedlichen Zusammensetzungen und Geometrien untersucht werden. Die verwendeten Hydrogele wurden hinsichtlich der Diffusionsprozesse sowie ihrer Quellkinetik charakterisiert, um deren Sensitivität, Selektivität, Reproduzierbarkeit und Ansprechzeit gegenüber den physiologischen Parametern (pH, pCO2, Glukose) zu verbessern. Die aufgebauten pCO2-Sensoren zeigten vielversprechende Ansprechzeiten von wenigen Minuten. Die Glukose und pH-Sensoren wiesen im physiologischen Medium (PBS) deutlich höhere Ansprechzeiten von mehreren Stunden auf. Die Kombination von piezoresistiven Drucksensoren mit Stimuli-sensitiven Hydrogelen bietet nicht nur eine große Vielfalt bezüglich der zu detektierenden Analyten, sondern ermöglicht auch miniaturisierte und implantierbare Sensoren für die kontinuierliche Erfassung von physiologischen Parametern. So war die Verkapselung zum Schutz und zugleich zur Gewährleistung der Biokompatibilität und ohne Beeinträchtigung der Funktionalität und Flexibilität der elektronischen Bauteile das Ziel. Dazu wurden die Sensoren mit dem Polymer Parylene C eingehaust, dass zusätzlich eine Polyethylenglykolschicht enthielt. Hierfür wurden Blockcopolymere mittels Ringöffnungspolymerisation synthetisiert, die Polyaminosäuren als Linkermoleküle und PEG zur gezielten Funktionalisierung enthalten. Nach kovalenter Anbindung an die inerte Parylene C-Oberfläche zeigten sich deutlich veränderte Oberflächeneigenschaften und eine verbesserte Zellkompatibilität und Hämokompatibilität. Zudem wurde der sogenannte Tarnkappeneffekt von PEG-Ketten, die sich in der Schicht nach außen ausrichten, festgestellt. Damit wurde Adsorption von Proteinen (Fibronektin, Fibrinogen), die in Entzündungsreaktionen, der Zelladhäsion sowie der Blutgerinnung maßgebend sind, deutlich verringert. / In this work a new class of implantable biochemical sensors with a high sensitivity at physiological pH (pH 7,4) and glucose (2 – 20 mM) ranges were developed and tested. The glucose sensitive hydrogel was made of acrylamide and N,N′-methylene-bis(acrylamide) as a crosslinker (AAm/APB/BIS, 80/20/0,75 mol%). The swelling mechanism was based on the reversible interaction of sugar molecules and the boronic acid groups in the hydrogel. Also a pH sensitive hydrogel made of 2-(dimethylamino) ethyl methacrylate (DMAEMA), hydroxypropyl-methacrylat (HPMA) and the crosslinker tetraethylene glycol dimethacrylate (TEGDMA) with different molar ratios and geometries was characterized. The swelling kinetics as well as the diffusion processes of different hydrogels were studied to advance sensitivity, selectivity, reproducibility and response time with respect to physiological parameters (pH, pCO2, glucose). pCO2 sensors showed promising short response times of about 4 min whereas glucose and pH sensors displayed longer response times of several hours in phosphate-buffered saline solution. The combination of piezoresistive pressure sensors and stimuli-sensitive hydrogels enables a great diversity of detecting analytes as well as miniaturized and implantable sensors for continuous measuring of physiological parameters. However, to implant the sensors an encapsulation strategy is needed that secures the electronics as well as ensures the biocompatibility without loss of functionality and flexibility. For this, the devices were coated with the polymer parylene C and an additional layer of blockcopolymers composed of polyaminoacid (PAA) and polyethyleneglycol (PEG) blocks synthesized via ring-opening polymerization. The functionalization units are carried out by the PEG blocks whereas the PAA blocks perform as linker molecules onto the activated parylene C surface. After covalent coupling of blockcopolymers to the inert polymer the surface characteristics changed and hence the cell and blood compatibility was improved. Furthermore the stealth effect of the outwards PEG chains was utilized to reduce the adsorption of proteins like fibronectin or fibrinogen. These proteins play a major role in inflammatory processes, cell adhesion and blood coagulation. The results gave proof that the encapsulation leads to decisively reduced physiological reactions.

This thesis examines how the pressure sensors can be used in rehabilitation for patients with weakened hand strength. The rehabilitation process usually contains everyday tasks to evaluate the patient’s capability and the tools for this part of the rehabilitation process are few. The challenges will be to find a suitable sensor for the application and how to implement the sensor in a versatile prototype with direct feedback for the user. To solve this problem, research will be conducted on different pressure sensor types to determine the most suitable one for this implementation. The resulting prototype is utilizing a force sensing resistor (FSR) mounted on a glove together with a module that presents direct feedback to the patient and caretaker. The glove has pressure sensors in each fingertip to detect the applied force for each individual finger when the patient grips an object. To present the feedback, a visual interface is created in the form of a hand with a LED for each finger, which provides direct visual feedback and a display to present numerical data. / Denna avhandling undersöker hur trycksensorer kan användas vid rehabilitering av patienter med försvagad handstyrka. Rehabiliteringsprocessen innehåller vanligtvis vardagliga uppgifter för att utvärdera patientens förmåga och nuvarande hjälpmedel är få. Utmaningarna är att hitta en lämplig sensor för applikationen och hur man kan implementera sensorn i en mångsidig prototyp med en direkt återkoppling för användaren. För att lösa detta problem kommer forskning att genomföras på olika typer av trycksensorer. Detta görs för att kunna bestämma den mest lämpade sensortypen för denna implementering. Den resulterande prototypen består av en handske med kraft känsliga resistorer (FSR) och en separat modul som ger direkt återkoppling till patienten och vårdtagaren. Handsken har en sensor i varje fingertopp för att detektera applicerad kraft för varje enskilt finger när patienten greppar ett föremål. För att presentera data från sensorerna skapas ett visuellt gränssnitt. Gränssnittet är i form av en hand med lysdioder i varje finger för direkt återkoppling och en bildskärm för att presentera numeriska data.

Implantable sensors have been extensively investigated to facilitate diagnosis or to provide a means to generated closed loop control of therapy by yielding in vivo measurements of physical and chemical signals. Biodegradable sensors which degrade gradually after they are no longer functionally needed exhibit great potential in acute or shorter-term medical diagnostic and sensing applications due to the advantages of (a) exclusion of the need to a secondary surgery for sensor removal, and (b) reduction of the risk of long-term infection. The objective of this research is to design and characterize microfabricated RF wireless pressure sensors that are made of completely biodegradable materials and degrade at time-controlled manner (in the order of years and months). This was achieved by means of investigation of appropriate biodegradable materials and development of appropriate fabrication processes for these non-standard (Microelectromechanical systems) MEMS materials. Four subareas of research are performed: (1) Design of sensors that operate wirelessly and are made of biodegradable materials. The structure of the wireless sensor consists a very compact and relatively simple design of passive LC resonant circuits embedded in a polymer dielectric package. To design the sensor with a particular resonant frequency range, an electromagnetic model of the sensor and a mechanical model for circular plate are developed. The geometry of the sensor is established based on the analytical and finite element simulations results. (2) Investigation of the biodegradable materials in the application of implantable biodegradable wireless sensors to achieve controllable degradation lifetimes. Commercially available and FDA approved biodegradable polymers poly(L-lactic acid) (PLLA) and a "shell-core" structure of poly(lactic-co-glycolic acid) (PLGA) and polyvinyl alcohol (PVA) are utilized as the dielectric package for slow and rapid degradation sensors, respectively. Biodegradable metallic zinc and zinc/iron couples are chosen as conductor materials. The degradation behavior of Zn and Zn/Fe-couple are investigated in vitro. (3) Development of novel fabrication processes. The process exploit the advantages of MEMS technology in fabricating miniaturized devices, while protecting vulnerable biodegradable materials from the strong and/or hazardous chemicals that are commonly used in conventional MEMS fabrication process. These new processes enable the fabrication of biocompatible and biodegradable 3-D devices with embedded, near-hermetic cavities. (4) Testing the pressure response functionality and studying the degradation behavior of the wireless biodegradable pressure sensors. Both PLLA-based and PLGA/PVA-based sensors are characterized in vitro by being immersed in 0.9% saline for prolonged time. All the sensors exhibit three stages of behavior in vitro: equilibration, functional lifetime, and performance degradation. During the functional lifetime, most sensors exhibit fully stable functionality. The PLLA-based sensors show no significant weight loss within 8 month and are expected to fully degrade after 2 years, while the PLGA/PVA-based sensors can degrade completely within 26 days.

Det finns många sensormetoder för vattennivåmätning ute på marknaden idag. Målet för forskningsstudien är att presentera och jämföra några av de mätningsmetoder som finns på marknaden för nivåmätning. I studien jämförs modellerna för trycksensorer, flytsensorer, ultraljudssensor och elektromagnetisk sensor för att sedan se vilken sensor som passar bäst för just mätningar av vattennivåer. Genom, datainsamlingen från sök motorerna Google scholar och Mittuniversitetets egen databas Primo har fakta samlats. Informationen har sedan bearbetas och jämförts mot behoven från Vattenfall som ska göra tre sensorbyten på vattenkraftverket i Stugun. Resultatet av studien visade slutsatsen att utifrån kravspecifikationerna Vattenfall gav så var en trycksensor det bästa alternativet för Stugun. Studien gjorde så att Vattenfall köpte in tre stycken Waterpilot FMX21, 22 mm som sedan sattes på plats och kalibrerades. / There are many sensor methods for water level measurement on the market today. The aim of the research study is to present and compare some of the measurement methods available on the market for level measurement. In the study, the models for pressure sensors, flow sensors, ultrasonic sensors and electromagnetic sensors are compared to see which sensor is most suitable for precise measurements of water levels. Through the data collection from the search engines Google scholar and Mid University of Sweden own database Primo, facts have been gathered. The information has since been processed and compared to the needs of Vattenfall, which will do three sensor changes at the Stugun hydropower plant. The result of the study showed that according to the requirement specifications of Vattenfall, a pressure sensor was the best alternative for Stugun. The study resulted in Vattenfall purchasing three Waterpilot FMX21, 22 mm, which were then put in place and calibrated.

This diploma thesis deals with a portable working place for automated measuring of pressure characteristic dependence on ventilator air flow and dependence of pressure loss on air flow for electrical machines and other devices. The goal of this thesis is to design and create the working place with performance validation measure.

Les travaux de thèse portent sur le développement de méthodologies d'élaboration de dispositifs à base de polymères PDMS, destinés à des applications médicales. Ce travail s'appuie sur deux volets applicatifs : le développement de matrices de micro-capteurs capacitifs souples portables destinées à la mesure de champs de pression dans un contexte de suivi d'appuis du corps humain, et le développement d'une technique de collage réversible de composants PDMS dans une application de laboratoire sur puce en micro-fluidique. Dans ces travaux, les propriétés mécaniques du PDMS sont déterminées expérimentalement et à l'aide de modélisations numériques, afin d'identifier les éléments essentiels du dimensionnement des micro-capteurs capacitifs. Différents types de micro-capteurs de pression souples sont réalisés par un procédé de microfabrication à transfert de films. Ce procédé est optimisé à chacune de ses étapes afin d'obtenir un procédé fiable et reproductible. Les caractérisations électromécaniques montrent que les capteurs fabriqués sont opérationnels et adaptés aux applications médicales visées. Les capteurs de pression normale ont une variation de capacité de 3 à 17 % à 10 N - 300 kPa, adaptée à une application dentaire. Les capteurs à trois axes de sensibilité ont une résolution spatiale de 25 mm2, et une sensibilité de 4 % à 3 N en compression et 1,4 % par Newton en cisaillement pur, et sont adaptés à une application de mesure de la pression plantaire destinée à l'analyse de la marche et la détection des hyper-appuis. Par ailleurs, deux méthodes différentes permettant le collage réversible de composants PDMS sont développées. Les dispositifs microfluidiques fabriqués avec ces méthodes peuvent être utilisés avec jusqu'à 5 cycles de collage/décollage, et travailler à débit élevé (500 µL/min, correspondant à une pression de 148 kPa). Les méthodologies développées dans ces travaux ouvrent la voie à l'élaboration de dispositifs à base de PDMS performants et optimisés pour répondre à des cahiers des charges exigeants pour des applications biomédicales ciblées. / This thesis focuses on the development of methodologies dedicated to the development of PDMS-based devices, which are required in medical applications. Two objective applications are considered in this work: i) the development of wearable flexible micro-sensors arrays for measuring pressure fields on human body and ii) the development of a reversible bonding technique of PDMS components dedicated to microfluidic chips. In this work, the mechanical properties of PDMS are determined using experiments and computations; they allow identifying the essential elements of the design of capacitive micro-sensors. The manufacturing process is reliable and reproducible, and different types of flexible pressure sensor have been fabricated by a film transfer process. Electromechanical characterizations show that the fabricated sensors are fully operational and suitable for the intended applications. Normal pressure sensors have a capacitance change ranging from 3 to 17% under a 10 N - 300 kPa - load, which is suitable for dental applications. Fabricated triaxial sensor arrays have a spatial resolution of 25 mm2, and a sensitivity of 4% under 3 N load in compression, and 1.4% / N under shear. These features are suitable for plantar pressure measurements required in gait analyses or for the detection of over-pressures. Besides, two different process methods for the reversible bonding of PDMS devices are developed. The microfluidic devices fabrcitated with these methods can be used within up to 5 “bonding & peeling off” cycles, and can be working at high microfluidic flows (500 µL / min, corresponding to a pressure of 148 kPa). The methodologies developed in these works open the way to the design and fabrication of PDMS-based devices suitable for demanding biomedical applications.