25 research outputs found
In-body Communications Exploiting Light:A Proof-of-concept Study Using ex vivo Tissue Samples
This article presents a feasibility study on the transmission of information through the biological tissues exploiting light. The experimental results demonstrating the potentials of optical wireless communications through biological tissues (OCBT) are presented. The main application of the proposed technology is in-body communications, where wireless connectivity needs to be provided to implanted electronic devices, such as pacemakers, cardiac defibrillators, and smart pills, for instance. Traditionally, in-body communications are performed using radio and acoustic waves. However, light has several fundamental advantages making the proposed technology highly attractive for this purpose. In particular, optical communications are highly secure, private, safe, and in many cases, extremely simple with the potential of low-power implementation. In the experiments, near-infrared light was used, as the light propagation in biotissues is more favorable in this part of the spectrum. The amount of light exposure given to biotissues was controlled to keep it within the safety limits. Information transmission experiments were carried out with the temperature-controlled ex vivo samples of porcine tissue. The tissue temperature was found to be significantly affecting the light propagation process. Communication performance with respect to the biotissue thickness and light direction was assessed. The results showed that optical channels to and from the possible implant are nearly reciprocal. Communication links were established to the deepness of more than four centimeters, and the data rates of up to 100 Kbps were obtained. The encouraging results of this study allow us to anticipate the potential applications of the proposed light-based technology to communicate with the various electronic devices implanted at different depths in the human body
A Three â tier bio-implantable sensor monitoring and communications platform
One major hindrance to the advent of novel bio-implantable sensor technologies is the need for a reliable power source and data communications platform capable of continuously, remotely, and wirelessly monitoring deeply implantable biomedical devices.
This research proposes the feasibility and potential of combining well established, âhuman-friendly' inductive and ultrasonic technologies to produce a proof-of-concept, generic, multi-tier power transfer and data communication platform suitable for low-power, periodically-activated implantable analogue bio-sensors.
In the inductive sub-system presented, 5 W of power is transferred across a 10 mm gap between a single pair of 39 mm (primary) and 33 mm (secondary) circular printed spiral coils (PSCs). These are printed using an 8000 dpi resolution photoplotter and fabricated on PCB by wet-etching, to the maximum permissible density.
Our ultrasonic sub-system, consisting of a single pair of Pz21 (transmitter) and Pz26 (receiver) piezoelectric PZT ceramic discs driven by low-frequency, radial/planar excitation (-31 mode), without acoustic matching layers, is also reported here for the first time. The discs are characterised by propagation tank test and directly driven by the inductively coupled power to deliver 29 ÎŒW to a receiver (implant) employing a low voltage start-up IC positioned 70 mm deep within a homogeneous liquid phantom. No batteries are used.
The deep implant is thus intermittently powered every 800 ms to charge a capacitor which enables its microcontroller, operating with a 500 kHz clock, to transmit a single nibble (4 bits) of digitized sensed data over a period of ~18 ms from deep within the phantom, to the outside world.
A power transfer efficiency of 83% using our prototype CMOS logic-gate IC driver is reported for the inductively coupled part of the system. Overall prototype system power consumption is 2.3 W with a total power transfer efficiency of 1% achieved across the tiers
Toward Brain Area Sensor Wireless Network
RĂSUMĂ De nouvelles approches d'interfaçage neuronal de haute performance sont requises pour les interfaces cerveau-machine (BMI) actuelles. Cela nĂ©cessite des capacitĂ©s d'enregistrement/stimulation performantes en termes de vitesse, qualitĂ© et quantitĂ©, câest Ă dire une bande passante Ă frĂ©quence plus Ă©levĂ©e, une rĂ©solution spatiale, un signal sur bruit et une zone plus large pour
l'interface avec le cortex cérébral. Dans ce mémoire, nous parlons de l'idée générale proposant une méthode d'interfaçage neuronal qui, en comparaison avec l'électroencéphalographie (EEG), l'électrocorticographie (ECoG) et les méthodes d'interfaçage intracortical conventionnelles à une seule unité, offre de meilleures caractéristiques pour implémenter des IMC plus performants. Les avantages de la nouvelle approche sont 1) une résolution spatiale plus élevée - en dessous dumillimÚtre,
et une qualité de signal plus élevée - en termes de rapport signal sur bruit et de contenu fréquentiel - comparé aux méthodes EEG et ECoG; 2) un caractÚre moins invasif que
l'ECoG oĂč l'enlĂšvement du crĂąne sous une opĂ©ration d'enregistrement / stimulation est nĂ©cessaire;
3) une plus grande faisabilitĂ© de la libre circulation du patient Ă l'Ă©tude - par rapport aux deux mĂ©thodes EEG et ECoG oĂč de nombreux fils sont connectĂ©s au patient en cours d'opĂ©ration; 4) une utilisation Ă long terme puisque l'interface implantable est sans fil - par rapport aux deux
méthodes EEG et ECoG qui offrent des temps limités de fonctionnement. Nous présentons l'architecture d'un réseau sans fil de microsystÚmes implantables, que nous appelons Brain Area Sensor NETwork (Brain-ASNET). Il y a deux défis principaux dans la réalisation du projet Brain-ASNET. 1) la conception et la mise en oeuvre d'un émetteur-récepteur
RF de faible consommation compatible avec la puce de capteurs de réseau implantable, et, 2) la conception d'un protocole de réseau de capteurs sans fil (WSN) ad-hoc économe en énergie. Dans ce mémoire, nous présentons un protocole de réseau ad-hoc économe en énergie pour le
réseau désiré, ainsi qu'un procédé pour surmonter le problÚme de la longueur de paquet variable causé par le processus de remplissage de bit dans le protocole HDLC standard. Le protocole adhoc proposé conçu pour Brain-ASNET présente une meilleure efficacité énergétique par rapport
aux protocoles standards tels que ZigBee, Bluetooth et Wi-Fi ainsi que des protocoles ad-hoc de pointe. Le protocole a Ă©tĂ© conçu et testĂ© par MATLAB et Simulink.----------ABSTRACT New high-performance neural interfacing approaches are demanded for todayâs Brain-Machine Interfaces (BMI). This requires high-performance recording/stimulation capabilities in terms of speed, quality, and quantity, i.e. higher frequency bandwidth, spatial resolution, signal-to-noise, and wider area to interface with the cerebral cortex. In this thesis, we talk about the general
proposed idea of a neural interfacing method which in comparison with Electroencephalography (EEG), Electrocorticography (ECoG), and, conventional Single-Unit Intracortical neural interfacing methods offers better features to implement higher-performance BMIs. The new
approach advantages are 1) higher spatial resolution â down to sub-millimeter, and higher signal quality â in terms of signal-to-noise ratio and frequency content â compared to both EEG and ECoG methods. 2) being less invasive than ECoG where skull removal Under recording/stimulation surgery is required. 3) higher feasibility of freely movement of patient under study â compared to both EEG and ECoG methods where lots of wires are connected to the patient under operation. 4) long-term usage as the implantable interface is wireless â compared to both EEG and ECoG methods where it is practical for only a limited time under operation.
We present the architecture of a wireless network of implantable microsystems, which we call it Brain Area Sensor NETwork (Brain-ASNET). There are two main challenges in realization of the proposed Brain-ASNET. 1) design and implementation of power-hungry RF transceiver of the
implantable network sensors' chip, and, 2) design of an energy-efficient ad-hoc Wireless Sensor Network (WSN) protocol. In this thesis, we introduce an energy-efficient ad-hoc network protocol for the desired network,
along with a method to overcome the issue of variable packet length caused by bit stuffing process in standard HDLC protocol. The proposed ad-hoc protocol designed for Brain-ASNET shows better energy-efficiency compared to standard protocols like ZigBee, Bluetooth, and Wi-Fi
as well as state-of-the-art ad-hoc protocols. The protocol was designed and tested by MATLAB and Simulink
Effects of biocompatible encapsulations on the acoustic characteristics of CMUTs
Advances in modern medicine enable the use of medical implants for the treatment of an increasing number of diseases. If different implanted systems need to communicate with each other, data transmission using ultrasound is a promising solution. In this dissertation, an encapsulation strategy, which allows the use of capacitive micromachined ultrasonic transducers (CMUTs) within conventional implant housings, was developed and evaluated for the first time. The novel encapsulation approach consists of a silicone layer for coupling the CMUT to a layer of polyether ether ketone (PEEK) or titanium. Both materials are widely used for medical implant housings. Finite element simulations, complemented by measurements in air and in immersion as well as ex vivo experiments, have shown that effective data transmission with data rates of minimum 0.8 Mbps is possible over at least 6 cm with this encapsulation strategy.Die Fortschritte in der modernen Medizin ermöglichen immer hĂ€ufiger den Einsatz von medizinischen Implantaten zur Therapie. In AnwendungsfĂ€llen, die eine Kommunikation mehrerer implantierter Systeme untereinander erfordern, stellt die DatenĂŒbertragung mit Hilfe akustischer Wellen eine vielversprechende Lösung dar. HierfĂŒr ist eine biokompatible Kapselung nötig, die eine effiziente DatenĂŒbertragung nicht verhindert. In dieser Arbeit wird erstmals eine Kapselungsstrategie entwickelt und evaluiert, die den Einsatz von kapazitiven mikromechanischen Ultraschallwandlern (CMUTs) innerhalb konventioneller ImplantatgehĂ€use ermöglicht. Die untersuchte neuartige Kapselung besteht aus einer Silikonschicht zur Ankopplung an eine Schicht aus Polyetheretherketon (PEEK) oder Titan, zwei weitverbreitete Materialien fĂŒr die Kapselung medizinischer Implantate. Finite Elemente Simulationen, Messungen in Luft und FlĂŒssigkeit sowie ex vivo Experimente haben gezeigt, dass mit dieser Kapselungsstrategie eine effektive DatenĂŒbertragung ĂŒber mindestens 6 cm möglich ist. Die in ex vivo Experimenten ermittelten Frequenzbandbreiten der gekapselten CMUTs ermöglichen Datenraten von mindestens 0.8 Mbps. Ein zusĂ€tzlicher experimenteller Vergleich mit herkömmlichen Kapselungen fĂŒr CMUTs bestĂ€tigt das groĂe Potenzial der neuartigen Kapselung aus Silikon und PEEK. AbschlieĂend wurden zukĂŒnftige Ansatzpunkte zur Steigerung von Signalamplitude und Datenrate identifiziert und diskutiert
The Internet of Torts: Expanding Civil Liability Standards to Address Corporate Remote Interference
Thanks to the proliferation of internet-connected devices that constitute the âInternet of Thingsâ (âIoTâ), companies can now remotely and automatically alter or deactivate household items. In addition to empowering industry at the expense of individuals, this remote interference can cause property damage and bodily injury when an otherwise operational car, alarm system, or implanted medical device abruptly ceases to function.
Even as the potential for harm escalates, contract and tort law work in tandem to shield IoT companies from liability. Exculpatory clauses limit civil remedies, IoT devicesâ bundled object/service nature thwarts implied warranty claims, and contractual notice of remote interference precludes common law tort suits. Meanwhile, absent a better understanding of how IoT-enabled injuries operate and propagate, judges are likely to apply products liability and negligence standards narrowly, in ways that curtail corporate liability.
But this is hardly the first time a new technology has altered social and power relations between industries and individuals, creating a potential liability inflection point. As before, we must decide what to incentivize and who to protect, with an awareness that the choices we make now will shape future assumptions about IoT companiesâ obligations and consumer rights. Accordingly, this Article proposes reforms to contract and tort law to expand corporate liability and minimize foreseeable consumer injury
The Future of Digital Spaces and Their Role in Democracy
This is the 13th"Future of the Internet" canvassing Pew Research Center and Elon University's Imagining the Internet Center have conducted together to gather expert views about important digital issues. In this report, the questions focused on the prospects for improvements in the tone and activities of the digital public sphere by 2035. This is a nonscientific canvassing based on a nonrandom sample; this broad array of opinions about where current trends may lead in the next decade represents only the points of view of the individuals who responded to the queries.Pew Research Center and Elon's Imagining the Internet Center built a database of experts to canvass from a wide range of fields, inviting professionals and policy people based in government bodies, nonprofits and foundations, technology businesses and think tanks, as well as interested academics and technology innovators. The predictions reported here came in response to a set of questions in an online canvassing conducted between June 29 and Aug. 2, 2021.In all, 862 technology innovators and developers, business and policy leaders, researchers and activists responded to at least one of the questions covered in this report. More on the methodology underlying this canvassing and the participants can be found in the section titled "About this canvassing of experts.