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

BPN738: Sensor Instrumentation to Improve Safety of U.S. Underground Coal Mines

Omid Mahdavipour
2016

Coal mining is recognized as a dangerous undertaking. Explosions of coal dust and gases that may exist underground (such as methane) are well-known hazards, in addition to which are unexpected structural collapses. In order to prevent the propagation of coal dust explosions, regulations require that inert rock dust is applied in underground areas of a coal mine. This project is aimed at creating real-time sensors to determine the explosibility of a coal and rock dust mixture and to communicate the results from inside the mine to safety personnel above ground.

Project...

BPN810: Non-Intrusive Wireless Current Metering of Standard Power Cables Using Vector Magnetic Field Measurements

Naing Ye Aung
Michael C. Lorek
2016

The goal of this project is to design a non-intrusive meter that can accurately measure the current in a standard electric power cable such as an extension cord or lamp cord by monitoring the vector magnetic field around it. Standard ’non-intrusive’ current meters either require the conductors to be separated and a single conductor inserted through a magnetic loop-based current transformer, or use an external magnetic field sensor and knowledge of the relative geometry of the wires and sensor. The net flux surrounding a standard power cable is zero because there is no net current in...

BPN722: 3D Ultrasonic Fingerprint Sensor On a Chip Using Piezoelectric Micromachined Ultrasonic Transducers (PMUT)

Joshua Kay
Joy Jiang
2016

We've successfully built a 500dpi, 4.75mm x 3.5mm monolithic ultrasonic fingerprint sensor on a chip with PMUT and integrated CMOS process that solves the problem of capacitive fingerprint sensors. The sensor is resilient to common contamination such as dirt, sweat, and oil by penetrating through them, and the sensor has the capability of capturing inner-finger feature such as dermis fingerprint. The capability of generating a three- dimensional, volumetric image of the finger surface and the tissues beneath the finger surface makes it extremely difficult to deceive the sensor with...

BPN466: Air-Coupled Piezoelectric Micromachined Ultrasonic Transducers

Scott Block
2016

Characterize air-coupled aluminum nitride piezoelectric micromachined ultrasound transducers (pMUTs) for use in range finding and gesture recognition applications. MEMS Aluminum Nitride (AlN) piezoelectric sensor technology has been chosen due to the relatively simple deposition process and compatibility with CMOS technology which enables the potential integration of the sensor and drive electronics on the same chip. Guided by both analytic and finite element models the optimum design parameters are chosen to obtain the desired resonant frequency, bandwidth, and maximum output sound...

BPN850: Wearable Sweat Rate Sensor

Li-Chia Tai
Wei Gao
2016

Wearable sensor is a growing area in which real-time monitoring of an individual’s health status can be realized. Recently, skin-worn sensors capable of screening biomarkers in human body fluids have been developed. Since human sweat contains physiologically insightful information, it is a wonderful candidate for non-invasive health monitoring. In particular, sweat rate information is highly desired as it can provide a more complete picture for sweat analysis. Hence, the objective of this work is to develop a wearable sensor capable of monitoring sweat rate.

Project end...

BPN433: A Micromechanical Power Converter

Ruonan Liu
2016

The overall goal of this project is to demonstrate a switched-mode power converter (e.g., a charge pump) using micromechanical switching elements that allow substantially higher voltages and potentially higher conversion efficiencies than transistor-switch based counterparts.

Project end date: 09/15/16

BPN842: Conductometric Gas Sensing Behavior of WS2 Aerogel

Wenjun Yan
2016

The gas sensing characteristics of a high surface area tungsten disulfide (WS2) aerogel are investigated. Gas sensors are fabricated by integrating a low-density WS2 aerogel onto a low power polysilicon microheater platform to provide control over the operating temperature. The response of the WS2 aerogel-based sensors to NO2, O2, and H2 is investigated with the sensing characteristics indicating p-type behavior. The optimum sensing temperature is found to be about 250 ℃;, when considering sensitivity, power consumption and response time. The role of O2 in H2 and NO2 sensing is...

BPN808: Acoustic Detection of Neural Activity

Konlin Shen
2016

There is a need for non-invasive methods of neural probing without genetic modification for both clinical and scientific use. It has been found that action potentials are accompanied by small nanometer-scale membrane deformations in firing neurons. These mechanical waves, known as “action waves”, travel down axons in concert with action potentials and could be used to determine neuronal activity. Because acoustic waves are far less lossy in the brain than electromagnetic waves, we believe it may be possible to detect action waves from neurons up to 4 millimeters away with a...

BPN812: Improving Micro-Oscillators Performance By Exploiting Nonlinearity

Martial Defoort
2016

Due to their small size, micro-sensors experience complex phenomena including the emergence of nonlinearities, affecting the intrinsic properties of the system and commonly known to reduce its performance. In the case of micro-resonators, while larger displacement typically leads to lower SNR, it also increases the nonlinearity of the system, altering both frequencies and quality factors which in turn decrease stability and thus performance. However, a careful control of these nonlinearities opens the way for new implementation schemes and improved stability in micro-sensors, such as...

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...