110 research outputs found

    Healthy aims: developing new medical implants and diagnostic equipment

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    Healthy Aims is a โ‚ฌ23-million, four-year project, funded under the EUโ€™s Information Society Technology Sixth Framework program to develop intelligent medical implants and diagnostic systems (www.healthyaims.org). The project has 25 partners from 10 countries, including commercial, clinical, and research groups. This consortium represents a combination of disciplines to design and fabricate new medical devices and components as well as to test them in laboratories and subsequent clinical trials. The project focuses on medical implants for nerve stimulation and diagnostic equipment based on straingauge technology

    Circuitry for a remotely powered bio-implantable gastric electrical stimulation system

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    Power to bio-implantable devices is usually supplied through a battery implanted with the system or through wires extending to an outside power source. The latter case with wires protruding out of the body can be unaesthetic in appearance and can cause infection. In this research, we consider an alternative way to power a bio-implantable microsystem. It involves using rechargeable lithium batteries. Here, power is delivered remotely to charge implanted battery or batteries. This approach avoids periodic surgery necessary for battery replacement. It also does not tie a person to an external power source at all times. This improves patientโ€™s quality of life. The present work involves design and fabrication of signal conditioning circuit for a remotely rechargeable, bio-implantable, Battery-powered Electrical Stimulation System (BESS). A rechargeable lithium ion battery with a voltage of 3.7 V powers the proposed circuit. The desired output, which goes directly to the electrodes, is a series of 10 V, 15 mA pulses with a duty cycle of 4.5 %. A second rechargeable lithium ion battery serves as back-up. A lithium ion charging chip is included which is connected to the designed IC through a logic interface. The two batteries work in tandem i.e. when one battery powers the IC the other gets recharged and vice versa thereby providing an uninterruptible output. The IC uses a series of charge pumps to get the required boost in voltage. The IC also includes voltage detector circuits to detect battery voltages, voltage regulator, pulse generator circuits, logic circuits and necessary switches. Individual subsystems of the IC were designed, simulated and fabricated using standard CMOS technology. Individual subsystem circuits were found to work satisfactorily except for the charge pump. A revised design is now under fabrication. The microsystem utilizes a hybrid approach. Experiments done with a bench-top circuit model to simulate the proposed IC showed that a 3 V battery with a capacity of 190 mAh could power the IC for 15 hrs and needed 4 hrs for recharging

    ์†Œํ˜•๋™๋ฌผ์˜ ๋‡Œ์‹ ๊ฒฝ ์ž๊ทน์„ ์œ„ํ•œ ์™„์ „ ์ด์‹ํ˜• ์‹ ๊ฒฝ์ž๊ทน๊ธฐ

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    ํ•™์œ„๋…ผ๋ฌธ(๋ฐ•์‚ฌ)--์„œ์šธ๋Œ€ํ•™๊ต ๋Œ€ํ•™์› :๊ณต๊ณผ๋Œ€ํ•™ ์ „๊ธฐยท์ •๋ณด๊ณตํ•™๋ถ€,2020. 2. ๊น€์„ฑ์ค€.In this study, a fully implantable neural stimulator that is designed to stimulate the brain in the small animal is described. Electrical stimulation of the small animal is applicable to pre-clinical study, and behavior study for neuroscience research, etc. Especially, behavior study of the freely moving animal is useful to observe the modulation of sensory and motor functions by the stimulation. It involves conditioning animal's movement response through directional neural stimulation on the region of interest. The main technique that enables such applications is the development of an implantable neural stimulator. Implantable neural stimulator is used to modulate the behavior of the animal, while it ensures the free movement of the animals. Therefore, stable operation in vivo and device size are important issues in the design of implantable neural stimulators. Conventional neural stimulators for brain stimulation of small animal are comprised of electrodes implanted in the brain and a pulse generation circuit mounted on the back of the animal. The electrical stimulation generated from the circuit is conveyed to the target region by the electrodes wire-connected with the circuit. The devices are powered by a large battery, and controlled by a microcontroller unit. While it represents a simple approach, it is subject to various potential risks including short operation time, infection at the wound, mechanical failure of the device, and animals being hindered to move naturally, etc. A neural stimulator that is miniaturized, fully implantable, low-powered, and capable of wireless communication is required. In this dissertation, a fully implantable stimulator with remote controllability, compact size, and minimal power consumption is suggested for freely moving animal application. The stimulator consists of modular units of surface-type and depth-type arrays for accessing target brain area, package for accommodating the stimulating electronics all of which are assembled after independent fabrication and implantation using customized flat cables and connectors. The electronics in the package contains ZigBee telemetry for low-power wireless communication, inductive link for recharging lithium battery, and an ASIC that generates biphasic pulse for neural stimulation. A dual-mode power-saving scheme with a duty cycling was applied to minimize the power consumption. All modules were packaged using liquid crystal polymer (LCP) to avoid any chemical reaction after implantation. To evaluate the fabricated stimulator, wireless operation test was conducted. Signal-to-Noise Ratio (SNR) of the ZigBee telemetry were measured, and its communication range and data streaming capacity were tested. The amount of power delivered during the charging session depending on the coil distance was measured. After the evaluation of the device functionality, the stimulator was implanted into rats to train the animals to turn to the left (or right) following a directional cue applied to the barrel cortex. Functionality of the device was also demonstrated in a three-dimensional maze structure, by guiding the rats to navigate better in the maze. Finally, several aspects of the fabricated device were discussed further.๋ณธ ์—ฐ๊ตฌ์—์„œ๋Š” ์†Œํ˜• ๋™๋ฌผ์˜ ๋‘๋‡Œ๋ฅผ ์ž๊ทนํ•˜๊ธฐ ์œ„ํ•œ ์™„์ „ ์ด์‹ํ˜• ์‹ ๊ฒฝ์ž๊ทน๊ธฐ๊ฐ€ ๊ฐœ๋ฐœ๋˜์—ˆ๋‹ค. ์†Œํ˜• ๋™๋ฌผ์˜ ์ „๊ธฐ์ž๊ทน์€ ์ „์ž„์ƒ ์—ฐ๊ตฌ, ์‹ ๊ฒฝ๊ณผํ•™ ์—ฐ๊ตฌ๋ฅผ ์œ„ํ•œ ํ–‰๋™์—ฐ๊ตฌ ๋“ฑ์— ํ™œ์šฉ๋œ๋‹ค. ํŠนํžˆ, ์ž์œ ๋กญ๊ฒŒ ์›€์ง์ด๋Š” ๋™๋ฌผ์„ ๋Œ€์ƒ์œผ๋กœ ํ•œ ํ–‰๋™ ์—ฐ๊ตฌ๋Š” ์ž๊ทน์— ์˜ํ•œ ๊ฐ๊ฐ ๋ฐ ์šด๋™ ๊ธฐ๋Šฅ์˜ ์กฐ์ ˆ์„ ๊ด€์ฐฐํ•˜๋Š” ๋ฐ ์œ ์šฉํ•˜๊ฒŒ ํ™œ์šฉ๋œ๋‹ค. ํ–‰๋™ ์—ฐ๊ตฌ๋Š” ๋‘๋‡Œ์˜ ํŠน์ • ๊ด€์‹ฌ ์˜์—ญ์„ ์ง์ ‘์ ์œผ๋กœ ์ž๊ทนํ•˜์—ฌ ๋™๋ฌผ์˜ ํ–‰๋™๋ฐ˜์‘์„ ์กฐ๊ฑดํ™”ํ•˜๋Š” ๋ฐฉ์‹์œผ๋กœ ์ˆ˜ํ–‰๋œ๋‹ค. ์ด๋Ÿฌํ•œ ์ ์šฉ์„ ๊ฐ€๋Šฅ์ผ€ ํ•˜๋Š” ํ•ต์‹ฌ๊ธฐ์ˆ ์€ ์ด์‹ํ˜• ์‹ ๊ฒฝ์ž๊ทน๊ธฐ์˜ ๊ฐœ๋ฐœ์ด๋‹ค. ์ด์‹ํ˜• ์‹ ๊ฒฝ์ž๊ทน๊ธฐ๋Š” ๋™๋ฌผ์˜ ์›€์ง์ž„์„ ๋ฐฉํ•ดํ•˜์ง€ ์•Š์œผ๋ฉด์„œ๋„ ๊ทธ ํ–‰๋™์„ ์กฐ์ ˆํ•˜๊ธฐ ์œ„ํ•ด ์‚ฌ์šฉ๋œ๋‹ค. ๋”ฐ๋ผ์„œ ๋™๋ฌผ ๋‚ด์—์„œ์˜ ์•ˆ์ •์ ์ธ ๋™์ž‘๊ณผ ์žฅ์น˜์˜ ํฌ๊ธฐ๊ฐ€ ์ด์‹ํ˜• ์‹ ๊ฒฝ์ž๊ทน๊ธฐ๋ฅผ ์„ค๊ณ„ํ•จ์— ์žˆ์–ด ์ค‘์š”ํ•œ ๋ฌธ์ œ์ด๋‹ค. ๊ธฐ์กด์˜ ์‹ ๊ฒฝ์ž๊ทน๊ธฐ๋Š” ๋‘๋‡Œ์— ์ด์‹๋˜๋Š” ์ „๊ทน ๋ถ€๋ถ„๊ณผ, ๋™๋ฌผ์˜ ๋“ฑ ๋ถ€๋ถ„์— ์œ„์น˜ํ•œ ํšŒ๋กœ๋ถ€๋ถ„์œผ๋กœ ๊ตฌ์„ฑ๋œ๋‹ค. ํšŒ๋กœ์—์„œ ์ƒ์‚ฐ๋œ ์ „๊ธฐ์ž๊ทน์€ ํšŒ๋กœ์™€ ์ „์„ ์œผ๋กœ ์—ฐ๊ฒฐ๋œ ์ „๊ทน์„ ํ†ตํ•ด ๋ชฉํ‘œ ์ง€์ ์œผ๋กœ ์ „๋‹ฌ๋œ๋‹ค. ์žฅ์น˜๋Š” ๋ฐฐํ„ฐ๋ฆฌ์— ์˜ํ•ด ๊ตฌ๋™๋˜๋ฉฐ, ๋‚ด์žฅ๋œ ๋งˆ์ดํฌ๋กœ ์ปจํŠธ๋กค๋Ÿฌ์— ์˜ํ•ด ์ œ์–ด๋œ๋‹ค. ์ด๋Š” ์‰ฝ๊ณ  ๊ฐ„๋‹จํ•œ ์ ‘๊ทผ๋ฐฉ์‹์ด์ง€๋งŒ, ์งง์€ ๋™์ž‘์‹œ๊ฐ„, ์ด์‹๋ถ€์œ„์˜ ๊ฐ์—ผ์ด๋‚˜ ์žฅ์น˜์˜ ๊ธฐ๊ณ„์  ๊ฒฐํ•จ, ๊ทธ๋ฆฌ๊ณ  ๋™๋ฌผ์˜ ์ž์—ฐ์Šค๋Ÿฌ์šด ์›€์ง์ž„ ๋ฐฉํ•ด ๋“ฑ ์—ฌ๋Ÿฌ ๋ฌธ์ œ์ ์„ ์•ผ๊ธฐํ•  ์ˆ˜ ์žˆ๋‹ค. ์ด๋Ÿฌํ•œ ๋ฌธ์ œ์˜ ๊ฐœ์„ ์„ ์œ„ํ•ด ๋ฌด์„ ํ†ต์‹ ์ด ๊ฐ€๋Šฅํ•˜๊ณ , ์ €์ „๋ ฅ, ์†Œํ˜•ํ™”๋œ ์™„์ „ ์ด์‹ํ˜• ์‹ ๊ฒฝ์ž๊ทน๊ธฐ์˜ ์„ค๊ณ„๊ฐ€ ํ•„์š”ํ•˜๋‹ค. ๋ณธ ์—ฐ๊ตฌ์—์„œ๋Š” ์ž์œ ๋กญ๊ฒŒ ์›€์ง์ด๋Š” ๋™๋ฌผ์— ์ ์šฉํ•˜๊ธฐ ์œ„ํ•˜์—ฌ ์›๊ฒฉ ์ œ์–ด๊ฐ€ ๊ฐ€๋Šฅํ•˜๋ฉฐ, ํฌ๊ธฐ๊ฐ€ ์ž‘๊ณ , ์†Œ๋ชจ์ „๋ ฅ์ด ์ตœ์†Œํ™”๋œ ์™„์ „์ด์‹ํ˜• ์ž๊ทน๊ธฐ๋ฅผ ์ œ์‹œํ•œ๋‹ค. ์„ค๊ณ„๋œ ์‹ ๊ฒฝ์ž๊ทน๊ธฐ๋Š” ๋ชฉํ‘œ๋กœ ํ•˜๋Š” ๋‘๋‡Œ ์˜์—ญ์— ์ ‘๊ทผํ•  ์ˆ˜ ์žˆ๋Š” ํ‘œ๋ฉดํ˜• ์ „๊ทน๊ณผ ํƒ์นจํ˜• ์ „๊ทน, ๊ทธ๋ฆฌ๊ณ  ์ž๊ทน ํŽ„์Šค ์ƒ์„ฑ ํšŒ๋กœ๋ฅผ ํฌํ•จํ•˜๋Š” ํŒจํ‚ค์ง€ ๋“ฑ์˜ ๋ชจ๋“ˆ๋“ค๋กœ ๊ตฌ์„ฑ๋˜๋ฉฐ, ๊ฐ๊ฐ์˜ ๋ชจ๋“ˆ์€ ๋…๋ฆฝ์ ์œผ๋กœ ์ œ์ž‘๋˜์–ด ๋™๋ฌผ์— ์ด์‹๋œ ๋’ค ์ผ€์ด๋ธ”๊ณผ ์ปค๋„ฅํ„ฐ๋กœ ์—ฐ๊ฒฐ๋œ๋‹ค. ํŒจํ‚ค์ง€ ๋‚ด๋ถ€์˜ ํšŒ๋กœ๋Š” ์ €์ „๋ ฅ ๋ฌด์„ ํ†ต์‹ ์„ ์œ„ํ•œ ์ง€๊ทธ๋น„ ํŠธ๋žœ์‹œ๋ฒ„, ๋ฆฌํŠฌ ๋ฐฐํ„ฐ๋ฆฌ์˜ ์žฌ์ถฉ์ „์„ ์œ„ํ•œ ์ธ๋•ํ‹ฐ๋ธŒ ๋งํฌ, ๊ทธ๋ฆฌ๊ณ  ์‹ ๊ฒฝ์ž๊ทน์„ ์œ„ํ•œ ์ด์ƒ์„ฑ ์ž๊ทนํŒŒํ˜•์„ ์ƒ์„ฑํ•˜๋Š” ASIC์œผ๋กœ ๊ตฌ์„ฑ๋œ๋‹ค. ์ „๋ ฅ ์ ˆ๊ฐ์„ ์œ„ํ•ด ๋‘ ๊ฐœ์˜ ๋ชจ๋“œ๋ฅผ ํ†ตํ•ด ์‚ฌ์šฉ๋ฅ ์„ ์กฐ์ ˆํ•˜๋Š” ๋ฐฉ์‹์ด ์žฅ์น˜์— ์ ์šฉ๋œ๋‹ค. ๋ชจ๋“  ๋ชจ๋“ˆ๋“ค์€ ์ด์‹ ํ›„์˜ ์ƒ๋ฌผํ•™์ , ํ™”ํ•™์  ์•ˆ์ •์„ฑ์„ ์œ„ํ•ด ์•ก์ • ํด๋ฆฌ๋จธ๋กœ ํŒจํ‚ค์ง•๋˜์—ˆ๋‹ค. ์ œ์ž‘๋œ ์‹ ๊ฒฝ์ž๊ทน๊ธฐ๋ฅผ ํ‰๊ฐ€ํ•˜๊ธฐ ์œ„ํ•ด ๋ฌด์„  ๋™์ž‘ ํ…Œ์ŠคํŠธ๊ฐ€ ์ˆ˜ํ–‰๋˜์—ˆ๋‹ค. ์ง€๊ทธ๋น„ ํ†ต์‹ ์˜ ์‹ ํ˜ธ ๋Œ€ ์žก์Œ๋น„๊ฐ€ ์ธก์ •๋˜์—ˆ์œผ๋ฉฐ, ํ•ด๋‹น ํ†ต์‹ ์˜ ๋™์ž‘๊ฑฐ๋ฆฌ ๋ฐ ๋ฐ์ดํ„ฐ ์ŠคํŠธ๋ฆฌ๋ฐ ์„ฑ๋Šฅ์ด ๊ฒ€์‚ฌ๋˜์—ˆ๊ณ , ์žฅ์น˜์˜ ์ถฉ์ „์ด ์ˆ˜ํ–‰๋  ๋•Œ ์ฝ”์ผ๊ฐ„์˜ ๊ฑฐ๋ฆฌ์— ๋”ฐ๋ผ ์ „์†ก๋˜๋Š” ์ „๋ ฅ์˜ ํฌ๊ธฐ๊ฐ€ ์ธก์ •๋˜์—ˆ๋‹ค. ์žฅ์น˜์˜ ํ‰๊ฐ€ ์ดํ›„, ์‹ ๊ฒฝ์ž๊ทน๊ธฐ๋Š” ์ฅ์— ์ด์‹๋˜์—ˆ์œผ๋ฉฐ, ํ•ด๋‹น ๋™๋ฌผ์€ ์ด์‹๋œ ์žฅ์น˜๋ฅผ ์ด์šฉํ•ด ๋ฐฉํ–ฅ ์‹ ํ˜ธ์— ๋”ฐ๋ผ ์ขŒ์šฐ๋กœ ์ด๋™ํ•˜๋„๋ก ํ›ˆ๋ จ๋˜์—ˆ๋‹ค. ๋˜ํ•œ, 3์ฐจ์› ๋ฏธ๋กœ ๊ตฌ์กฐ์—์„œ ์ฅ์˜ ์ด๋™๋ฐฉํ–ฅ์„ ์œ ๋„ํ•˜๋Š” ์‹คํ—˜์„ ํ†ตํ•˜์—ฌ ์žฅ์น˜์˜ ๊ธฐ๋Šฅ์„ฑ์„ ์ถ”๊ฐ€์ ์œผ๋กœ ๊ฒ€์ฆํ•˜์˜€๋‹ค. ๋งˆ์ง€๋ง‰์œผ๋กœ, ์ œ์ž‘๋œ ์žฅ์น˜์˜ ํŠน์ง•์ด ์—ฌ๋Ÿฌ ์ธก๋ฉด์—์„œ ์‹ฌ์ธต์ ์œผ๋กœ ๋…ผ์˜๋˜์—ˆ๋‹ค.Chapter 1 : Introduction 1 1.1. Neural Interface 2 1.1.1. Concept 2 1.1.2. Major Approaches 3 1.2. Neural Stimulator for Animal Brain Stimulation 5 1.2.1. Concept 5 1.2.2. Neural Stimulator for Freely Moving Small Animal 7 1.3. Suggested Approaches 8 1.3.1. Wireless Communication 8 1.3.2. Power Management 9 1.3.2.1. Wireless Power Transmission 10 1.3.2.2. Energy Harvesting 11 1.3.3. Full implantation 14 1.3.3.1. Polymer Packaging 14 1.3.3.2. Modular Configuration 16 1.4. Objectives of This Dissertation 16 Chapter 2 : Methods 18 2.1. Overview 19 2.1.1. Circuit Description 20 2.1.1.1. Pulse Generator ASIC 21 2.1.1.2. ZigBee Transceiver 23 2.1.1.3. Inductive Link 24 2.1.1.4. Energy Harvester 25 2.1.1.5. Surrounding Circuitries 26 2.1.2. Software Description 27 2.2. Antenna Design 29 2.2.1. RF Antenna 30 2.2.1.1. Design of Monopole Antenna 31 2.2.1.2. FEM Simulation 31 2.2.2. Inductive Link 36 2.2.2.1. Design of Coil Antenna 36 2.2.2.2. FEM Simulation 38 2.3. Device Fabrication 41 2.3.1. Circuit Assembly 41 2.3.2. Packaging 42 2.3.3. Electrode, Feedthrough, Cable, and Connector 43 2.4. Evaluations 45 2.4.1. Wireless Operation Test 46 2.4.1.1. Signal-to-Noise Ratio (SNR) Measurement 46 2.4.1.2. Communication Range Test 47 2.4.1.3. Device Operation Monitoring Test 48 2.4.2. Wireless Power Transmission 49 2.4.3. Electrochemical Measurements In Vitro 50 2.4.4. Animal Testing In Vivo 52 Chapter 3 : Results 57 3.1. Fabricated System 58 3.2. Wireless Operation Test 59 3.2.1. Signal-to-Noise Ratio Measurement 59 3.2.2. Communication Range Test 61 3.2.3. Device Operation Monitoring Test 62 3.3. Wireless Power Transmission 64 3.4. Electrochemical Measurements In Vitro 65 3.5. Animal Testing In Vivo 67 Chapter 4 : Discussion 73 4.1. Comparison with Conventional Devices 74 4.2. Safety of Device Operation 76 4.2.1. Safe Electrical Stimulation 76 4.2.2. Safe Wireless Power Transmission 80 4.3. Potential Applications 84 4.4. Opportunities for Further Improvements 86 4.4.1. Weight and Size 86 4.4.2. Long-Term Reliability 93 Chapter 5 : Conclusion 96 Reference 98 Appendix - Liquid Crystal Polymer (LCP) -Based Spinal Cord Stimulator 107 ๊ตญ๋ฌธ ์ดˆ๋ก 138 ๊ฐ์‚ฌ์˜ ๊ธ€ 140Docto

    SenseBack - An implantable system for bidirectional neural interfacing

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    Chronic in-vivo neurophysiology experiments require highly miniaturized, remotely powered multi-channel neural interfaces which are currently lacking in power or flexibility post implantation. In this article, to resolve this problem we present the SenseBack system, a post-implantation reprogrammable wireless 32-channel bidirectional neural interfacing that can enable chronic peripheral electrophysiology experiments in freely behaving small animals. The large number of channels for a peripheral neural interface, coupled with fully implantable hardware and complete software flexibility enable complex in-vivo studies where the system can adapt to evolving study needs as they arise. In complementary ex-vivo and in-vivo preparations, we demonstrate that this system can record neural signals and perform high-voltage, bipolar stimulation on any channel. In addition, we demonstrate transcutaneous power delivery and Bluetooth 5 data communication with a PC. The SenseBack system is capable of stimulation on any channel with ยฑ20 V of compliance and up to 315 ฮผA of current, and highly configurable recording with per-channel adjustable gain and filtering with 8 sets of 10-bit ADCs to sample data at 20 kHz for each channel. To the best of our knowledge this is the first such implantable research platform offering this level of performance and flexibility post-implantation (including complete reprogramming even after encapsulation) for small animal electrophysiology. Here we present initial acute trials, demonstrations and progress towards a system that we expect to enable a wide range of electrophysiology experiments in freely behaving animals

    An efficient telemetry system for restoring sight

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    PhD ThesisThe human nervous system can be damaged as a result of disease or trauma, causing conditions such as Parkinsonโ€™s disease. Most people try pharmaceuticals as a primary method of treatment. However, drugs cannot restore some cases, such as visual disorder. Alternatively, this impairment can be treated with electronic neural prostheses. A retinal prosthesis is an example of that for restoring sight, but it is not efficient and only people with retinal pigmentosa benefit from it. In such treatments, stimulation of the nervous system can be achieved by electrical or optical means. In the latter case, the nerves need to be rendered light sensitive via genetic means (optogenetics). High radiance photonic devices are then required to deliver light to the target tissue. Such optical approaches hold the potential to be more effective while causing less harm to the brain tissue. As these devices are implanted in tissue, wireless means need to be used to communicate with them. For this, IEEE 802.15.6 or Bluetooth protocols at 2.4GHz are potentially compatible with most advanced electronic devices, and are also safe and secure. Also, wireless power delivery can operate the implanted device. In this thesis, a fully wireless and efficient visual cortical stimulator was designed to restore the sight of the blind. This system is likely to address 40% of the causes of blindness. In general, the system can be divided into two parts, hardware and software. Hardware parts include a wireless power transfer design, the communication device, power management, a processor and the control unit, and the 3D design for assembly. The software part contains the image simplification, image compression, data encoding, pulse modulation, and the control system. Real-time video streaming is processed and sent over Bluetooth, and data are received by the LPC4330 six layer implanted board. After retrieving the compressed data, the processed data are again sent to the implanted electrode/optrode to stimulate the brainโ€™s nerve cells

    WIRELESS POWER MANAGEMENT CIRCUITS FOR BIOMEDICAL IMPLANTABLE SYSTEMS

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    Ph.DDOCTOR OF PHILOSOPH

    CIR-Myo News: Abstracts of the 2015 Spring Padua Muscle Days

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    Neurostimulator with Waveforms Inspired by Nature for Wearable Electro-Acupuncture

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    The work presented here has 3 goals: establish the need for novel neurostimulation waveform solutions through a literature review, develop a neurostimulation pulse generator, and verify the operation of the device for neurostimulation applications. The literature review discusses the importance of stimulation waveforms on the outcomes of neurostimulation, and proposes new directions for neurostimulation research that would help in improving the reproducibility and comparability between studies. The pulse generator circuit is then described that generates signals inspired by the shape of excitatory or inhibitory post-synaptic potentials (EPSP, IPSP). The circuit analytical equations are presented, and the effects of the circuit design components are discussed. The circuit is also analyzed with a capacitive load using a simplified Randles model to represent the electrode-electrolyte interface, and the output is measured in phosphate-buffered saline (PBS) solution as the load with acupuncture needles as electrodes. The circuit is designed to be used in different types of neurostimulators depending on the needs of the application, and to study the effects of varying neurostimulation waveforms. The circuit is used to develop a remote-controlled wearable veterinary electro-acupuncture machine. The device has a small form-factor and 3D printed enclosure, and has a weight of 75 g with leads attached. The device is powered by a 500 mAh lithium polymer battery, and was tested to last 6 hours. The device is tested in an electro-acupuncture animal study on cats performed at the Louisiana State University School of Veterinary Medicine, where it showed expected electro-acupuncture effects. Then, a 2-channel implementation of the device is presented, and tested to show independent output amplitude, frequency, and stimulation duration per channel. Finally, the software and hardware requirements for control of the wearable veterinary electro-acupuncture machine are detailed. The number of output channels is limited to the number of hardware PWM timers available for use. The Arduino software implements PWM control for the output amplitude and frequency. The stimulation duration control is provided using software timers. The communications protocol between the microcontroller board and Android App are described, and communications are performed via Bluetooth
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