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

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...

BPN879: A Wearable Impedance-Based Microfluidic Sensor for Sweat Rate Monitoring

Li-Chia Tai
2017

A flexible and wearable sensor is presented for real-time monitoring of localized perspiration rate of human subjects. These sweat rate measurements are validated through controlled syringe pumping and a commercial sweat collector. Real-time on-body perspiration rate evaluation of human subjects is performed through cycling experiments to examine the change in sweat rate with different power output. Since it has been shown that the concentrations of a large number of sweat biomarkers are strongly related to the variation of a subject's perspiration rate, this platform is anticipated...

BPN880: Synchronization in Micromachined Resonators

2018

Synchronization is a well-known phenomenon in nonlinear dynamics that is used to lock the frequencies of two oscillators for frequency stabilization applications. The simplest evidence of such frequency entrainment occurs between a self-sustained oscillator and an external tone2, when the latter is swept around the resonance frequency of the oscillator. Synchronization between two oscillators with frequencies related by an integer ratio can occur but requires coupling between the two modes. We present an experimental study of synchronization between two resonance modes of a single...

BPN872: Compact Voltage Sensor for Power Lines

Duy-Son Nguyen
2018

This project is designed to measure the line-to-line voltages of distribution and transmission power lines by using very compact and inexpensive sensors that operate at low voltages. On a two-wire power line, the measurement devices are mounted on only one of the lines. The devices can also be applied in open air power substations and in buildings where high voltage power lines (e.g., 12,400 AC Volts) are used.

Project end date: 01/30/18

BPN780: Impedance Spectroscopy to Monitor Fracture Healing

Monica C. Lin
2018

An estimated 15 million fracture injuries occur each year in the United States. Of these, 10% of fractures result in delayed or non-union, with this number rising to 46% when they occur in conjunction with vascular injury. Current methods of monitoring include taking X-rays and making clinical observations. However, radiographic techniques lag and physician examination of injury is fraught with subjectivity. No standardized methods exist to assess the extent of healing that has taken place in a fracture, revealing the need for a diagnostic device that can reliably detect non-union in...

BPN628: Novel Ultrasonic Fingerprint Sensor Based on High-Frequency Piezoelectric Micromachined Ultrasonic Transducers (PMUTs)

Xiaoyue (Joy) Jiang
Qi Wang
2018

This project presents the first MEMS ultrasonic fingerprint sensor with the capability to image epidermis and dermis layer fingerprints. The sensor is based on a piezoelectric micromachined ultrasonic transducer (PMUT) array that is bonded at wafer- level to complementary metal oxide semiconductor (CMOS) signal processing electronics to produce a pulse-echo ultrasonic imager on a chip. To meet the 500 DPI standard for consumer fingerprint sensors, the PMUT pitch was reduced by approximately a factor of two relative to an earlier design. We conducted a systematic design study of the...

BPN886: 2D Carbides as a New Family of Gas Sensing Materials with Wide Working Temperature Range

Xining Zang
Niravkumar Joshi
2018

Some of the 2d and 2d-like carbide exhibit tunable band structure with relatively high conductivity, which provides sensing function for dopants such as gas molecules. 2d-like carbide also has limited phase change induced nanostructure aggregation. With up to 1000K thermal stability, such carbides will be a better fit than other oxide and nitride materials in higher temperature sensing. For certain gases that require combustion sensing, nanostructure 2d-like carbides will be much stable and reliable. 2d-like Molybdenum carbide is three times more sensitive than graphene in response...