Physical Sensors & Devices

Research that includes:

  • Silicon MEMS actuators: comb, electro-thermal, and plastic deformation
  • Precision electronic sensing and measurements of capacitive, frequency, and coulombic MEMS variables
  • Structures and architectures for gyroscopes, accelerometers, micro strain gauges for direct application to rigid structures e.g., steel, and levitated MEMS

BPN731: Flexible Electrodes and Insertion Machine for Stable, Minimally-Invasive Neural Recording

Timothy L. Hanson
2016

Current approaches to interfacing with the nervous system mainly rely on stiff electrode materials, which work remarkably well, but suffer degradation from chronic immune response due to mechanical impedance mismatch and blood-brain barrier disruption. This current technology also poses limits on recording depth, spacing, and location. In this project we aim to ameliorate these issues by developing a system of very fine and flexible electrodes for recording from nervous tissue, a robotic system for manipulating and implanting these electrodes, and a means for integrating electrodes...

BPN802: Electret-Enabled Energy Harvesters for Use Near Current-Carrying Conductors

Zhiwei Wu
2017

The purpose of this project is to employ long-lived electrets in energy harvesters for use on power lines.

Project end date: 02/08/17

BPN599: MEMS Electronic Compass: Three-Axis Magnetometer

Soner Sonmezoglu
2017

High sensitivity, low cost, low power, and direct integration with MEMS inertial sensors, such as accelerometers and gyroscopes, make the MEMS magnetic sensor a very attractive option in consumer electronic devices. The goal of this project is to develop a low-power three axis MEMS magnetic sensor suitable for use as an electronic compass in smart phones and portable electronics. Our objective is to achieve a resolution of 100 nT/rt-Hz and power consumption of 0.1 mW/axis with DC power supply of 1.8 V. Although past devices designed by our group have demonstrated that our resolution...

BPN603: Micro Rate-Integrating Gyroscope

Parsa Taheri-Tehrani
2017

The goal of this project is to realize a micro rate-integrating gyroscope that produces an output signal proportional to rotation angle rather than rotation rate. This device would eliminate the need of integrating the gyroscope's rate output to obtain the angle. Gyroscope resonators have at least two resonant modes that can be coupled by Coriolis force. Difference in damping coefficients and stiffness of the resonant modes of the MEMS resonator known as anisodamping and anisoelasticity are main sources of error in RIG. So realizing a micro rate-integrating gyroscope can be achieved...

BPN838: Dosimetry Dust: An Implantable Dosimeter for Proton Beam Therapy Treatment of Ocular Melanomas

Stefanie V. Garcia
2017

Proton beam therapy is a well-established medical procedure for treating certain kinds of cancer, and is uniquely suited for treatment of head, neck, and eye tumors. In order to effectively treat a patient’s tumor, medical physicists have developed various simulations to model proton interactions with tissue and create a patient specific treatment plan that determines optimal gaze angles, the depth of penetration, and width of the spread-out-Bragg Peak necessary to encompass the target tumor. Despite the continuous improvements in medical physics treatment plan simulations, improper...

BPN714: Impedance Sensing Device to Monitor Pressure Ulcers

Amy Liao
Monica C. Lin
2018

Chronic cutaneous wounds affect millions of people each year and take billions of dollars to treat. Formation of pressure ulcers is considered a "never event" - an inexcusable, adverse event that occurs in a healthcare setting. Current monitoring solutions (pressure-distributing beds, repositioning patients every few hours, etc) are very expensive and labor intensive. In response to this challenge, we are developing a novel, flexible monitoring device that utilizes impedance spectroscopy to measure and characterize tissue health, thus allowing physicians to objectively monitor...

BPN765: Full-Field Strain Sensor for Hernia Mesh Repairs

Amy Liao
2017

Each year, more than 400,000 ventral hernia repairs are performed in the United States. A hernia is the protrusion of an organ through a weak spot in the surrounding muscle or connective tissue that normal contains it. Large ventral hernias (hernias that occur in the abdominal wall) are typically treated by suturing in a surgical mesh to cover and overlap the hernia defect. The surgical mesh provides additional support to the damaged tissue surrounding the hernia. However, in 25-40% of patients, the hernia repair fails, resulting in recurrence of the hernia, along with other...

BPN883: Microchannel Contacting of Crystalline Silicon Solar Cells

James Bullock
Mark Hettick
2017

There is tremendous interest in reducing losses caused by the metal contacts in silicon photovoltaics, particularly the optical and resistive losses of the front metal grid. One commonly sought after goal is the creation of high aspect-ratio metal fingers which provide an optically narrow and low resistance pathway to the external circuit. Currently, the most widely used metal contact deposition techniques are limited to widths and aspect-ratios of ~40 μm and ~0.5, respectively. In this study, we introduce the use of a micropatterned polydimethylsiloxane encapsulation layer to form...

BPN817: Ultra-Low Power AlN MEMS-CMOS Microphones and Accelerometers

Yuri Kusano
2017

State-of-the-art (SOA) physical sensors used to monitor changes in the environment require active electronics that continuously consume power (in the order of mW) limiting the sensor lifetime to months or less. This project targets the integration of low frequency sensors with wake-up electronics that operates below 10nW (50dB lower than the SOA) and achieve high probability of detection (POD) (>95%) and low false alarm rate (FAR) (<1h^-1). To improve the sensor performance at low frequencies we design piezoelectric AlN MEMS microphones and accelerometers with high voltage...

BPN818: Fully-Integrated Wearable Sensor Arrays for Multiplexed In Situ Perspiration Analysis

Hnin Y.Y. Nyein
Wei Gao
Mallika Bariya
2017

A flexible and wearable microsensor array is described for simultaneous multiplexed monitoring of heavy metals in human body fluids. Zn, Cd, Pb, Cu, and Hg ions are chosen as target analytes for detection via electrochemical square wave anodic stripping voltammetry (SWASV) on Au and Bi microelectrodes. The oxidation peaks of these metals are calibrated and compensated by incorporating a skin temperature sensor. High selectivity, repeatability, and flexibility of the sensor arrays are presented. Human sweat and urine samples are collected for heavy metal analysis, and measured results...