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

BPN920: Robust, Multimodal Sweat Sensors with High-Throughput Fabrication

Noelle Davis
Ashwin Aggarwal
Sorour Darvishi

In the field of sweat monitoring, many sensors have been piloted with one or two subjects over limited periods of time, but there is a need for prolonged, large-scale studies to establish reliable physiological correlations that account for diverse subjects, activities, and environments. Chemical sensors provide the concentration of analytes of interest, including sodium, potassium, and glucose, while sweat rate sensors provide standalone information on nerve function and hydration. Monitoring both of these in parallel will enable the decoding of concentrations of analytes that are...

BPN946: Sensor for Natural Sweat Analysis

Sorour Darvishi

Wearable sweat sensors have emerged as attractive platforms for non-invasive health monitoring. While most sweat sensors have relied on exercise or chemical stimulation to generate sweat, natural thermoregulatory sweat is an attractive alternative as it can be accessed during routine and even sedentary activity without impeding user lifestyles, while also potentially preserving correlations between sweat and blood biomarkers. For rapid accumulation of natural sweat that enables quick, single-point measurement of sweat analytes, we develop a simple, skin-attachable sensing platform to...

BPN979: Developing Sweat Rate Sensors Using New Sensing Modalities

Ashwin Aggarwal
Manik Dautta
Luis Fernando
Ayala Cardona

The skin surface naturally secretes sweat for thermoregulation during sedentary and physical activities at varying rates, which can sometimes indicate underlying health conditions such as nerve damages or metabolic disorders. As measuring low secretion rates poses a challenge for traditional microfluidic devices, we present new ways to collect such sweat rates precisely.

Project ended: 08/01/2023

BPN753: Ratio-Metric Readout Technique for MEMS Gyroscopes with Force Feedback

Burak Eminoglu
Igor I. Izyumin
Yu-Ching Yeh

Scale factor accuracy is critical for navigation grade gyroscopes. Traditional MEMS vibratory gyroscopes with force feedback provide good resolution, but their scale factor depends on a plethora of parameters including proof mass bias voltage, drive mode velocity,dimensions of the forcer electrodes,and mass. This project develops a ratio-metric readout technique for force feedback gyroscopes that provides a precise scale factor. Scale factor variations over 12 days are reduced from 547ppm p-p to 23ppm p-p, and temperature coefficient of the scale factor is reduced from 560ppm/C to...

BPN467: Aluminum Nitride Ultrasonic Doppler Velocity Sensor

Stefon E. Shelton
Hongsoo Choi

The goal of this project is to develop a high precision MEMS ultrasonic Doppler velocity sensor utilizing an array of Aluminum Nitride transducer elements for use in personal navigation units. Aluminum Nitride has been chosen for its desirable piezoelectric properties and compatibility with CMOS processes which allows for on chip integration of MEMS and electronics. In our device we aim to produce an ultrasound source-receiver pair with integrated signal processing circuitry on a single chip. To determine the velocity we will be developing and implementing an efficient and accurate...

BPN962: Insect-Scale Flying Robots

Fanping Sui
Kamyar Behrouzi
Wei Yue

Insect-scale untethered flight with maneuverability is very challenging toward possible practical applications and attitude-stabilized flight (hovering) is one of the first steps for long-time air flight operations. In this project, we introduce the insect-scale, untethered, rotating-wing aerial vehicles with inherent stability by the gyroscopic effect to achieve several key advancements: (1) powered by alternating magnetic fields wirelessly; (2) 160-mg in weight and 20.0-mm-in-diameter in size – smallest untethered flying robot in the world; and (3) attitude-stabilized flights (...

BPN974: Lidar-Camera Fusion for Autonomous Driving

Philip L. Jacobson

Within the past few decades, the goal of fully-autonomous vehicles has moved from a thought experiment to a potential reality thanks to advances in machine intelligence. One of the key challenges to still be overcome is the building of robotic perception systems which can achieve performance on-par with or surpassing that of humans. Currently, most autonomous driving researchers rely on several different modalities for collecting visual information, namely lidar, radar, and cameras. Although relying on lidar for perception has the drawback of high cost, maturing lidar technology has opened...

BPN876: Metal-Organic Frameworks for Chemical Sensing with High Selectivity

Alireza Pourghaderi
Isaac Zakaria

A classic challenge in gas sensing is the tunability of the sensing material for the selective absorption of target gases without interference from unwanted species. Metal-organic frameworks (MOFs), made up of metal-cluster nodes connected by organic linkers, can achieve selective adsorption owing to their high chemical and structural tunability. Their selectivity and flexibility make MOFs attractive for gas sensing, as realized in novel low-power, low-footprint, on-chip devices such as the chemical-sensitive field-effect transistor, previously demonstrated by our group. In this...

BPN913: Mixed-Dye ZIF-8-Based Colorimetric Carbon Dioxide Sensing for Robust Indoor Air Quality Monitoring

Adrian K. Davey

Indoor levels of carbon dioxide (700 parts per million and up), when coupled with volatile organic compounds (VOCs) under most temperature and humidity environments, can induce fatigue, nausea, nasal irritation, and related human health symptoms. Toward the realization of rapid, inexpensive, passive, and visually-obvious indoor gas sensors, we present dye-functionalized metal-organic frameworks (MOFs), which employ distinct color changes to measure indoor carbon dioxide concentrations. Our latest generation of the sensor, based on the coupling of multiple dyes blended with MOF...

BPN948: Wireless Tactile Stimulation with MEMS Inchworm Motors

Dillon Acker-James

The goal of this project is to make an untethered MEMS tactile stimulator. Electrostatic inchworm motors made in SOI substrates routinely generate 1-15 mN of force and 2 mm/s travel, making them a viable option for a millimeter-scale wireless tactile stimulator. Collaborating with Professor Eric Paulos and his students, our first step is to conduct haptic sensation surveys in order to understand what a user feels based on different forces. Our current chips provide a force range of 1mN up to 15mN, but we plan to increase this in the future. Our next step would be to integrate the MEMS...