Archived

A Flush-Mount Piezoelectric MEMS Microphone for Aeroacoustic Flight Testing Applications

In their effort to locate, understand and mitigate the impact of noise sources on an aircraft, aeroacousticiansare in need of a high performance, low cost microphone to combat the increasing noise restrictions on commercial aircraft. Existing commercial sensors, even with their relatively high cost, in some cases constrain the quality and type of measurement that may be achieved. One such constraint is that the physical size and characteristics of the sensors limit the optimal locations in which the sensors may be placed. Previous generations of MEMS aeroacoustic microphones have failed to address the need for a sensor that can be packaged and installed with a smooth front surface to be used for boundary layer measurements in a fuselage array at cruise conditions. Additionally, these microphones must meet demanding requirements, including the sensing of high sound pressure levels (>160 dB) with low distortion (<3%) and high sensitivity stability (with respect to moisture and freezing) over temperatures from -60°F to 150°F. This work addresses the limitations of existing MEMS piezoelectric microphones used in aeroacoustic applications by incorporating through-silicon vias(TSVs) into the fabrication to eliminate the use of wirebondsthat affect the flow field and create an overall flush-mount microphone package.

Modeling of the Magnetic Particle Imaging Signal Due to Magnetic Nanoparticles

Magnetic Particle Imaging (MPI) is a new tomographic imaging technique that maps the spatial distribution of iron oxide magnetic nanoparticles (MNPs) in real time and with spatial resolution that is on par or better than other biomedical imaging techniques. In this project, we will develop a theoretical foundation relating the properties of MNPs and MPI magnetic field conditions to the MPI signal strength and resolution. These efforts will yield design rules that will guide the rational design of future generations of MNP tracers for MPI. The proposed research will enable development of a novel biomedical imaging technique capable of high resolution real time imaging using nontoxic tracers suitable for a variety of biomedical applications.

Directed Nanoparticle Assembly by Electrophoretic Deposition

This industry-sponsored project is funded by the MIST Center. The specific details of this project are confidential.

 

The Multi-functional Integrated System Technology (MIST) Center is an NSF Industry/University Cooperative Research Center (I/UCRC) led by the University of Florida and the University of Central Florida. Our mission is to facilitate integration of novel materials, processes, devices, and circuits into multi-functional systems through research partnerships between university, industry, and government stakeholders. With ~30 faculty participants from 6 different departments, the MIST Center serves as an early-stage research sandbox for developing next-generation smart systems in the Internet of Things era.

High-Performance CoPt Micromagnets

This industry-sponsored project is funded by the MIST Center.  The specific details of this project are confidential.

 

The Multi-functional Integrated System Technology (MIST) Center is an NSF Industry/University Cooperative Research Center (I/UCRC) led by the University of Florida and the University of Central Florida. Our mission is to facilitate integration of novel materials, processes, devices, and circuits into multi-functional systems through research partnerships between university, industry, and government stakeholders. With ~30 faculty participants from 6 different departments, the MIST Center serves as an early-stage research sandbox for developing next-generation smart systems in the Internet of Things era.

Processes for Manufacturing High-Performance Magnetic Materials in Electronic Systems

The objective of this research is to develop new manufacturing processes for the magnetic components used in modern electronic systems. The goal is improve the manufacturability, performance, and energy efficiency of power supplies and communication devices, while simultaneously reducing their size and weight. A novel process is used to combine the properties of two different magnetic materials by embedding magnetic particles of one type of material inside of a second material. The result is a new, hybrid magnetic material that exhibits improved material properties compared to existing materials. In the long run, these new magnetic materials are aimed to enable next-generation mobile electronics, communication systems, robotics, and medical devices. The project will strengthen an industry/university research partnership between the University of Florida and Electron Energy Corporation via technical exchange and a graduate student summer internship. The project also aims to broaden participation and retention of female and minority students in STEM career fields.

Distributed Wireless Power Transmission to Compact Electronic Devices

Motivation

The maintenance procedures to replace the batteries typically require physical contact or wire connections with the devices, which may be inconvenient, difficult, or costly. Even where batteries can be easily recharged, the ever-growing hunger for portable power presents an important technical challenge. For example, the modern dismounted Warfighter carries a vast array of battery-powered technologies. The logistical burden of monitoring, recharging, and replacing these batteries is overwhelming, and no soldier would willingly go on mission without fully charged batteries. For soldier power systems, there are two main issues: the large number of different electronic devices and the requirement for constant charging for maximum mission readiness.

To address these issues, the project explore the development of an electrodynamic wireless power transmission (EWPT) technology that is capable of wirelessly delivering power to a spatially distributed collection of power receivers over distances of a few centimeters to a few meters. Compared to the more widely studied inductively coupled wireless power transmission schemes, the EWPT technology enables the power receivers to be physically much smaller and with fewer restrictions on their orientation.

In the EWPT system, a transmitting coil is connected to a power source and carries an alternating current. The field generated by the transmitting coil moves a permanent magnet in the receiver through electrodynamic (magnetic) forces and/or torques. The magnet is mounted on a spring and is allowed to oscillate. This motion is then converted into electrical energy using an electrodynamic transduction within the receiver. Even using fairly weak magnetic fields, significant mechanical oscillations can be induced when the receiver magnet is excited near its mechanical resonance (assuming an underdamped mechanical system).

Magnetic Collection of Joint-Level Osteoarthritis Biomarkers

Motivation

Diagnosis of early-stage osteoarthritis (OA), a disease stage where emerging  therapeutics have demonstrated potential to reduce and prevent OA progression in animal models, remains a significant clinical challenge. However, OA early-stage detection could lead to interventions and change in lifestyle that would reverse the chronic cascade of joint destruction found in the OA-affected joint. Clinically, OA is diagnosed through radiographs and physical exams, yet these diagnostics are relatively poor at detecting early-stage OA. A significant need exists for technologies that facilitate early-stage OA diagnosis. Therefore, direct assessment of molecular changes within an OA-affected joint would overcome these limitations.  The goal of this project is to develop a novel magnetic nanoparticle-based technique to collect OA biomarkers from synovial fluid without the need to remove fluid from the joint space.

Our preliminary studies demonstrate a proof-of-concept for magnetic harvesting; however, additional refinement is needed to accurately and repeatedly relate the amount of biomarker collected to the initial biomarker concentration in the synovial fluid.

Ultrashort Pulsed Laser Micromachining of Sapphire Sensors for High Temperature Environments

 

As engineers seek to design more efficient gas turbines, they require a detailed understanding of fundamental thermal-fluid phenomena, as well as active control methods, in high-temperature environments. The high-temperature requirement is based on the increasing turbine inlet temperatures, which have risen to 1500 C, in combined cycle systems in order to improve turbine peak power and efficiency. The limited survivability of silicon-based MEMS sensors in high-temperature and harsh environments has caused researchers to investigate other materials for high-temperature MEMS-based sensors; more specifically sapphire.

 

Sapphire’s material properties make its entry into the world of high temperature sensors promising, but it also renders most traditional MEMS manufacturing methods impractical. Sapphire’s chemical inertness does not allow for effective dry or wet etching; consequently, a more effective method of machining the material is necessary. One potential solution is to use laser ablation, or material removal by vaporization due to localized heat input, to pattern the material. Femtosecond and picosecond pulsed lasers have shown the ability to reduce or eliminate the thermal damage issues of longer pulsed lasers. These lasers are classified as ultrashort pulse width because the duration of the pulse is so short that it does not allow for thermal conduction into the crystal lattice of the material.

Tailoring Energy Flow in Magnetic Oscillator Arrays

Despite the fact that nonlinearities are inherent in many natural and engineered systems, it is common for engineers to remove, or attempt to remove, all nonlinearity from their designs. Although this simplifies the performance analyses, it also overlooks a wide array of phenomena that could potentially enable fundamental breakthroughs.

The objective of this project is to derive fundamental insights for complex arrays of nonlinearly coupled oscillators, using structures defined as magneto-mechanical lattices. The magneto-mechanical lattices comprise periodic arrays of dynamically interacting magnets, which can be conceptualized as an array of equivalent springs and masses, or alternatively, as a solid composed of artificial macro-atoms. The nonlinear magnetic coupling is to be theoretically tailored to exploit nonlinear energy transfer behaviors, such as reconfiguring bandgaps, energy localization, internal resonances, etc. These nonlinear phenomena are to be experimentally demonstrated and measured by fabricated magneto-mechanical lattices.