Page 12 - ASME SMASIS 2016 Program

Symposia

Biography tion is to use the linear piezoelectric constitutive equation, but it will cover
Jeremy Schaffer is a well-tenured research engineer & scientist develop- only one specific pre-stress case. New modeling technique will be needed
ing precision materials with Fort Wayne Metals Research Products Corp. to cover in depth the modeling and characterization issues for magneto-
(FWM, Fort Wayne, IN). He earned his materials’ focused MSME and strictive materials as well as investigating potential device applications.
Biomedical Engineering Ph.D. at Purdue University. The Fort Wayne- Current efforts on active and adaptive capabilities for the Army’s Next
based R&D group seeks to leverage principles of engineering and Generation Air and Ground Combat Vehicles will be discussed.
materials science toward improved material performance in medical and
other precision applications. Examples of current research areas include
nutrient-based metals for absorbable medical devices, fatigue-resistant Biography
metals for biostimulation lead systems, and new shape memory alloys for Dr. Yoo is a Research Engineer in the Vehicle Technology Directorate, at
medical and defense industries. In absorbable metals, the group is Army Research Laboratory. Prior to joining to ARL, he was Research
working to combine opposing paradigms, that being design against failure Scientist of the University of Maryland at the Alfred Gessow Rotorcraft
in permanent scaffolds, versus design towards complimentary “failure” in Center from 1999 to 2011. Dr. Yoo received his Ph.D. in Mechanical
temporary scaffolds to provide more ideal medical materials that do not Engineering from Yonsei University in South Korea, at 1999. He has
fail injuriously and improve the natural long term function of human tissues. studied in modal testing on vibration system and vibration isolation control
Towards community stewardship, the group is also designing medical using smart materials for his academic career.
materials that will serve to reduce healthcare cost while improving
functional benefit. Recently, he has investigated the research field of application develop-
ment with various smart materials, including magnetorheological (MR) fluid,

electrostrictive and magnetostrictive materials. He has been working 3
SYMPOSIUM 3 years simultaneously as a contractor at the Naval Surface Warfare Center
in Carderock since 2007 where he is expanding his expertise to the
magnetic material characterization. He has co-authored over 25 contribu-
MAGNETOSTRICTIVE MATERIAL FOR ARMY APPLICATIONS tions to international journals and has contributed over 48 papers to
international conference proceedings.

JinHyeong Yoo
Mechanics Division
U.S. Army Research Laboratory ADAPTIVE TRACKING CONTROL FOR LINEAR INFINITE-
Aberdeen Proving Ground, MD DIMENSIONAL SYSTEMS

Abstract Mark Balas
Magnetostrictive materials (e.g. galfenol, Terfenol-D) are distinguished by Embry-Riddle Aeronautical University
the phenomenon of dimensional changes occurring in response to Daytona Beach, FL
changes in the magnetization of these ferromagnetic materials. The
inverse is also true, whereby magnetization occurs in response to changes
in applied stress fields, so called Villari effect. Fe-Ga alloys (Galfenol) are
a particularly promising transducer material that combines highly desirable Abstract
mechanical attributes with superior magnetic properties. In contrast with Tracking an ensemble of basic signals is often required of control systems
typical piezo-ceramic materials, Galfenol is the most ductile of the current in general. Here we are given a linear continuous-time infinite-dimensional
transduction materials and appears to have an excellent ability to plant on a Hilbert space and a space of tracking signals generated by a
withstand mechanical shock and tension load. The Villari effect in Galfenol finite basis, and we show that there exists a stabilizing direct adaptive
can be used in various sensor configurations that utilizing a magnetic field control law that will stabilize the plant and cause it to asymptotically track
sensor, such as Hall Effect sensor or giant magnetoresistance (GMR) any member of this collection of signals. The plant is described by a
sensor. This stress-based permeability change is not time dependent and closed, densely defined linear operator that generates a continuous
can measure static loads. Galfenol also has low hysteresis and loses less semigroup of bounded operators on the Hilbert space of states. There is
than ~10% of its transduction maximum performance over a range of -20 to no state or parameter estimation used in this adaptive approach. Our
+80 ºC. In contrast to the piezoelectric materials, heating the material to results are illustrated by adaptive control of general linear diffusion
above its Curie temperature of 670 ºC does not permanently destroy its systems.
transduction capabilities. These characteristics make it possible to design
robust structural sensors and actuators that take advantage of tempera-
ture insensitivity and high strength under both compressive and tensile
loads. In order to design such robust sensors and actuators it is necessary Biography
to characterize magnetostrictive materials for use in harsh environment Mark Balas is a distinguished faculty member in Aerospace Engineering at
12 and develop an engineering model to describe the non-linear behavior as Embry-Riddle Aeronautical University. He was formerly the Guthrie
functions of magnetization and external stress. The simplest approxima- Nicholson Professor of Electrical Engineering and former Head of the Elec-
trical and Computer Engineering Department at the University of