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Design, Simulation And Testing Of Biomimetic Directional Acoustic Sensors, Brendan Francis Apr 2021

Design, Simulation And Testing Of Biomimetic Directional Acoustic Sensors, Brendan Francis

Thinking Matters Symposium

The Ormia ochracea, a species of parasitic fly, has become the focal point in sound localization research because of its finely tuned hearing abilities. The female of this species uses its super highly directional hearing to pinpoint the call of a host cricket, with hypersensitivity of frequency and phase difference, to reach and dispose of its eggs on the host. The goal of this study was to further the research of a previous Project in Professor Guvench’s group which implemented MEMS (Micro Electro-Mechanical System) technology on a chip to replicate these abilities. In this iteration, however, some commercially available …


Mems Directional Acoustic Sensors, Colby Damren Apr 2021

Mems Directional Acoustic Sensors, Colby Damren

Thinking Matters Symposium

The purpose of my project is to test and verify two Micro-Electro-Mechanical-System (MEMS) microphones. The two MEMS devices are biomimetic microphones that imitate the eardrums of the Ormia Ochracea, a parasitic fly that listens for host crickets to lay their eggs. The MEMS microphones mimic the eardrum spacing of the Ormia Ochracea with a spacing of 1000um. This is roughly twice the opening of the Ormia Ochracea. The microphones will be tested for directionality inside a wooden box. This box will be lined with beveled foam to prevent any echo or outside noise from interfering with the results. These results …


Fabrication Of Silicon Microneedles For Dermal Interstitial Fluid Extraction In Human Subjects, Caleb A. Berry Aug 2020

Fabrication Of Silicon Microneedles For Dermal Interstitial Fluid Extraction In Human Subjects, Caleb A. Berry

Electronic Theses and Dissertations

The goal of this project is to design and develop a fabrication process for silicon microneedle arrays to extract dermal interstitial fluid (ISF) from human skin. ISF is a cell- free, living tissue medium that is known to contain many of the same, clinical biomarkers of general health, stress response and immune status as in blood. However, a significant barrier to adoption of ISF as a diagnostic matrix is the lack of a rapid, minimally invasive method of access and collection for analysis. Microfabricated chips containing arrays of microneedles that can rapidly and painlessly access and collect dermal ISF for …


Development Of A Counter-Flow Thermal Gradient Microfluidic Device, Shayan Davani Feb 2019

Development Of A Counter-Flow Thermal Gradient Microfluidic Device, Shayan Davani

Doctoral Dissertations

This work presents a novel counter-flow design for thermal stabilization of microfluidic thermal reactors. In these reactors, precise control of temperature of the liquid sample is achieved by moving the liquid sample through the thermal zones established ideally through the conduction in the solid material of the device. The goal here is to establish a linear thermal distribution when there is no flow and to minimize the temperature change at flow condition. External convection as well as internal flowinduced effects influence the prescribed thermal distribution. The counter-flow thermal gradient device developed in this study is capable of both stabilizing the …


Localized Blood Occlusion Generation In An In-Vitro Circulatory Catheter System, Ryan D. Harris, Qi Yang, Hyowon Lee Aug 2017

Localized Blood Occlusion Generation In An In-Vitro Circulatory Catheter System, Ryan D. Harris, Qi Yang, Hyowon Lee

The Summer Undergraduate Research Fellowship (SURF) Symposium

Hydrocephalus is a debilitating neurological disorder that involves the accumulation of cerebrospinal fluid in a ventricle of the brain. The implantation of a catheter commonly treats hydrocephalus with drainage. These catheters have a short lifespan due to obstruction from biological materials. Shunt systems have an extremely high failure rate of more than 40% failed within 1 year and up to 85% failed within 10 years. Previously, polymer-based flexible implantable magnetic micro-actuators were developed to clean up the catheter by mechanical vibration. We have demonstrated clearing of bacteria attachment and are proceeding to examine clearing effects on larger clotting materials, such …


Mechanical Reliability Of Implantable Polyimide-Based Magnetic Microactuators For Biofouling Removal, Christian G. Figueroa-Espada, Qi Yang, Hyowon Lee Aug 2016

Mechanical Reliability Of Implantable Polyimide-Based Magnetic Microactuators For Biofouling Removal, Christian G. Figueroa-Espada, Qi Yang, Hyowon Lee

The Summer Undergraduate Research Fellowship (SURF) Symposium

Hydrocephalus is a neurological disorder that typically requires a long-term implantation of a shunt system to manage its symptoms. These shunt systems are notorious for their extremely high failure rate. More than 40% of all implanted shunt systems fail within the first year of implantation. On average, 85% of all hydrocephalus patients with shunt systems undergo at least two shunt-revision surgeries within 10 years of implantation. A large portion of this high failure rate can be attributed to biofouling-related obstructions and infections. Previously, we developed flexible polyimide-based magnetic microactuators to remove obstructions formed on hydrocephalus shunts. To test the long-term …


Micro Electrostatic Actuation Of A Silicon Diaphragm, Matthew W. Samples Jun 2015

Micro Electrostatic Actuation Of A Silicon Diaphragm, Matthew W. Samples

Master's Theses

There are a number of applications, from hearing aids to microfluidic pumps, which utilize micro-scale actuating diaphragms. These MEMS (micro-electromechanical system) devices can be actuated by electrostatic forces, which utilize an induced electric field to pull two charged plates towards one another. Such devices were fabricated and electrostatic actuation of the diaphragms was performed to analyze its viability as a micro-speaker. The long-term performance of such products requires adequate diaphragm deflection to create audible pressure waves with relatively low maximum stresses to ensure a high cycle fatigue life. With these requirements, initial calculations and FEA (finite element analysis) were performed …


Nanoenabled Microelectromechanical Sensor For Volatile Organic Chemical Detection, Chiara Zuniga, Matteo Rinaldi, Samuel M. Khamis, A. T. Johnson, Gianluca Piazza Feb 2013

Nanoenabled Microelectromechanical Sensor For Volatile Organic Chemical Detection, Chiara Zuniga, Matteo Rinaldi, Samuel M. Khamis, A. T. Johnson, Gianluca Piazza

Matteo Rinaldi

A nanoenabled gravimetric chemical sensor prototype based on the large scale integration of single-stranded DNA (ss-DNA) decorated single-walled carbon nanotubes (SWNTs) as nanofunctionalization layer for aluminum nitride contour-mode resonant microelectromechanical (MEM) gravimetric sensors has been demonstrated. The capability of two distinct single strands of DNA bound to SWNTs to enhance differently the adsorption of volatile organic compounds such as dinitroluene (simulant for explosive vapor) and dymethyl-methylphosphonate (simulant for nerve agent sarin) has been verified experimentally. Different levels of sensitivity (17.3 and 28 KHz µm^2/fg) due to separate frequencies of operation (287 and 450 MHz) on the same die have also …


Nanoenabled Microelectromechanical Sensor For Volatile Organic Chemical Detection, Chiara Zuniga, Matteo Rinaldi, Samuel M. Khamis, A. T. Johnson, Gianluca Piazza Jun 2009

Nanoenabled Microelectromechanical Sensor For Volatile Organic Chemical Detection, Chiara Zuniga, Matteo Rinaldi, Samuel M. Khamis, A. T. Johnson, Gianluca Piazza

Matteo Rinaldi

A nanoenabled gravimetric chemical sensor prototype based on the large scale integration of single-stranded DNA (ss-DNA) decorated single-walled carbon nanotubes (SWNTs) as nanofunctionalization layer for aluminum nitride contour-mode resonant microelectromechanical (MEM) gravimetric sensors has been demonstrated. The capability of two distinct single strands of DNA bound to SWNTs to enhance differently the adsorption of volatile organic compounds such as dinitroluene (simulant for explosive vapor) and dymethyl-methylphosphonate (simulant for nerve agent sarin) has been verified experimentally. Different levels of sensitivity (17.3 and 28 KHz µm^2/fg) due to separate frequencies of operation (287 and 450 MHz) on the same die have also …


Continuous Glucose Monitoring Microsensor With A Nanoscale Conducting Matrix And Redox Mediator, Daniel Pesantez Jan 2009

Continuous Glucose Monitoring Microsensor With A Nanoscale Conducting Matrix And Redox Mediator, Daniel Pesantez

Legacy Theses & Dissertations (2009 - 2024)

The major limiting factor in kidney clinical transplantation is the shortage of transplantable organs. The current inability to distinguish viability from non-viability on a prospective basis represents a major obstacle in any attempt to expand organ donor criteria. Consequently, a way to measure and monitor a relevant analyte to assess kidney viability is needed. For the first time, the initial development and characterization of a metabolic microsensor to assess kidney viability is presented. The rate of glucose consumption appears to serve as an indicator of kidney metabolism that may distinguish reversible from irreversible kidney damage. The proposed MetaSense (Metabolic Sensor) …


The Development Of An In Vivo Spinal Fusion Monitor Using Microelectromechanical (Mems) Technology To Create Implantable Microsensors, Lisa Anne Ferrara Jan 2008

The Development Of An In Vivo Spinal Fusion Monitor Using Microelectromechanical (Mems) Technology To Create Implantable Microsensors, Lisa Anne Ferrara

ETD Archive

Surgical fusion of the spine is a conventional approach, and often last alternative, to the correction of a degenerative painful spinal segment. The procedure involves the surgical removal of the intervertebral disc at the problematic site, and the placement of a bone graft that is commonly harvested from the patients iliac crest and placed within the discectomized space. The surrounding bone is expected to incorporate and remodel into the bone graft to eventually provide an immobilized site. Spinal instrumentation often accompanies the bone graft to provide further immobility to the targeted site, thus augmenting the fusion process. However, the status …


Mems (Micro-Electro-Mechanical-Systems) Based Microfluidic Platforms For Magnetic Cell Separation, Pulak Nath Jan 2008

Mems (Micro-Electro-Mechanical-Systems) Based Microfluidic Platforms For Magnetic Cell Separation, Pulak Nath

ETD Archive

Microfluidic platforms for magnetic cell separation were developed and investigated for isolation of magnetic particles and magnetically tagged cells from a fluidic sample. Two types of magnetic separation platforms were considered: an Isodynamic Open Gradient Magnetic Sorter (OGMS) and a multistage bio-ferrograph. Miniaturized magnets were designed using magnetostatic simulation software, microfluidic channels were fabricated using microfabrication technology and magnetic separation was investigated using video microscopy and digital image processing. The isodynamic OGMS consisted of an external magnetic circuit and a microfabricated channel (biochip) with embedded magnetic elements. The biochip is placed inside the magnetic field of the external circuit to …


Mems Transducer For Hearing Aid Device, Houwen Tang Jan 2008

Mems Transducer For Hearing Aid Device, Houwen Tang

Electronic Theses and Dissertations

A study of implantable middle ear MEMS piezoelectric transducer for hearing aids was developed. The physical vibration deflection at the tip of the transducer is simulated using finite element method. Further, a study of thermoelastic damping effect of four designed MEMS mirrors used as resonators is presented. An optical measurement system based on Mach-Zehnder interferometer is