Fabrication Technologies

As the field of hypersonic vehicle design develops, having shear stress data can aid in the minimization of 
drag source effects and verify results from computational fluid dynamics simulations. Transducer size, 
placement, and narrow bandwidth currently limit accurate shear stress measurements due to the small 
length and time scales seen in turbulent fluid motion and the issue of flow disruption. Shock wave and 
boundary layer effects also produce large thermal loads in hypersonic flows. The proposed research plan 

The goal of this project is to develop processes that will advance microfabrication technologies using stereolithography as the additive manufacturing (3D printing) method. This project focuses on fabrication of multifunctional devices that are both high resolution (tens of micrometers) and large area (tens of millimeters). The ability to fabricate functional microdevices using 3D printing can enable novel devices in the area of MEMs, sensors, actuators, microrobots, micro-optics, radio frequency, etc.

Understanding the character and dynamics of hypersonic boundary layers poses a considerable challenge to the design of hypersonic vehicles.  Specifically, being able to predict the location of laminar-to-turbulent transition is of critical concern as it affects heating rates, aerodynamic loading, and skin-friction drag, therefore impacting the design of the thermal protection system and thus the overall weight and performance of the vehicle.

We are developing ultra-compact antennas, where the antenna size is much smaller than the electromagnetic wavelength.

Pervasive wireless connectivity is a must for today’s interconnected world.  Many MHz-GHz communication systems require antennas with physical sizes that can be much larger than the entire size of the system.  It is difficult to achieve good antenna performance if the size of the antenna is less than 1/10^ththe electromagnetic wavelength (e.g. minimum of 3 cm at 1 GHz)

Detection of fecal indicating bacteria plays an important role in water quality monitoring to ensure safe human water contact and/or drinking.  Specifically, epidemiological studies by the U.S. Environmental Protection Agency (EPA) have shown strong correlations between illnesses and bacteria concentrations of Enterococci and E.

This collaborative research project will create a practical control scheme for large swarms of microrobots. These robots are typically no more than a few millimeters in length, and rely on an external power source and control signal. Currently, it is possible to steer the swarm as a whole to a single destination (or perhaps, to a desired average location). However, realizing the full potential benefits of microrobot swarms will require the ability to simultaneously send independent commands, either to individual robots or to small subgroups.

The aim of this project is to utilize the controllable nature of Graphene Oxide as an ultrathin separation membrane in biological applications, specifically targetting removal of uremic toxins. 

We are developing time-resolved dynamic pressure sensing technology for high-temperature (> 1000 °C) applications in the aerospace, energy, and automotive sectors and for chemical environment sensors for biotechnology companies.

This project is under DARPA's Magnetic Miniaturized and Monolithically Integrated Components (M3IC) program in the DARPA Microsystems Technology Office.

The objective of this effort is to develop thick-film magnetic materials that can be fabricated on semiconductor integrated circuits to enable highly miniaturized microwave components such as circulators and isolators operating in the 10 to 110 GHz frequency regime. These nonlinear, non-reciprocal components are critical for next generation radios, radar, and sensing systems for defense, consumer, automotive, and healthcare applications.

We seek to develop a platform that allows magnetic field sensing using a small footprint, in the absence of an external power supply. Our approach uses magnetoelectric nanofibers to create a zero-power magnetic field sensor. The challenge is to develop methods to assemble these materials into devices that leverage their unique anisotropic properties.

The figure of merit for magnetoelectric materials is the magnetoelectric coefficient, a measure of the amount of voltage generated with respect to the magnitude of the applied magnetic field. Bulk magnetoelectrics and thin films are limited by defects and substrate clamping respectively.  To overcome the limitations of thin-film based composite magnetoelectrics we have developed magnetoelectric bilayer structures on a single nanofiber, i.e., 1D magnetoelectrics. These materials are theoretically predicted to have magnetoelectric coupling coefficients that are orders of magnitude greater than their thin film counterparts. 

Magnetoelectric materials can be employed in a wide variety of applications including magnetic field sensors and tunable resonance energy harvesters.  By optimizing for material system and architecture, drastic increases in magnitude of voltage generated with decreased size can be achieved. This could allow for more sensitive magnetic field sensors appropriate for a wider array of applications and decreased size to allow for easier integration into ICs.