Woodruff School of Mechanical Engineering
Faculty Candidate Seminar
MEMS Design: From Ballistics to Biology
Dr. David Myers
Department of Pediatrics, Emory University
Thursday, April 2, 2015 at 2:00:00 PM
MRDC Building, Room 4211
Micro-Electro-Mechanical systems (MEMS) have the remarkable ability to measure physical phenomena such as temperature, acceleration, pressure, and strain with exceptional sensitivity in a small form factor. In my talk, I will present the design, fabrication, and testing of MEMS for two seemingly dissimilar applications, discussing how design principles and methodology for MEMS can be used to solve a variety of problems. The first half of the talk will focus on my contributions to creating a MEMS strain sensor capable of surviving extreme environmental conditions (600oC & 100,000 G), while maintaining nanostrain sensitivity. Such survivability gives the sensor the ability to survive forces encountered during ballistic explosions as well as a broad range of applications in automotive, energy, and manufacturing sectors. Furthermore, with nanostrain sensitivity and small form factor, I show how this device can be mounted on virtually any object to measure the real-time forces experienced by the object, offering new paradigms of force feedback and control. In the second half of my talk, I will discuss my work to apply the same techniques and design principles to create a MEMS diagnostic capable of measuring the individual nanomechanical contraction forces of platelets, the cells responsible for forming, stabilizing, and contracting blood clots. Changes in the overall mechanical stiffness of blood clots has been linked to both stroke and bleeding disorders, but is difficult to clinically assess due to a number of confounding factors. To address this, Iíve created an extremely robust, easy to make, and sensitive diagnostic based on mechanical principles. Using the diagnostic, Iíve been able to measure and establish ďtypicalĒ contraction forces from healthy donors and the mechanical and biochemical parameters that influence contraction. I will also discuss our recent clinical measurements from individuals with bleeding disorders and notable differences in contraction forces. Although these two cases have very different purposes and material sets, they both utilize microfabrication technology to precisely position mechanical elements which are useful for measuring nanomechanical forces. It is this commonality which enables MEMS to be useful and relevant in many different scientific disciplines despite being first proposed and patented 50 years ago.
David Myers is currently a Postdoctoral Fellow in the Department of Pediatrics at Emory University. Working with Wilbur Lam, MD, PhD, David is working on microsystems technologies aimed at better understanding the mechanics of clots and clot contraction. Davidís work has been supported by the American Heart Association through a postdoctoral fellowship, and he has received several abstract achievement awards from the American Society of Hematology. David received his PhD & MS in Mechanical Engineering at the University of California at Berkeley with Albert P. Pisano, PhD. His thesis work focused on the design, fabrication, and experimental use of high sensitivity silicon carbide strain sensors capable of surviving extreme temperatures (600oC) and shock (100,000 G).
Refreshments will be served.