Page 24 - ASME SMASIS 2017 Program

Awards
reversible change in wave energy focusing: a potential for acoustic field
morphing easily obtained through deployable, tessellated architectures.
Our experimental and theoretical studies directly translate the roles of
folding the tessellated array to the adaptations in spectral and spatial
wave propagation sensitivities for far field energy transmission. It is shown
that kinematic folding rules and flat-foldable tessellated arrays collectively
provide novel solutions to the long-standing challenges of conventional,
electronically-steered acoustic beamformers. While our examples
consider sound radiation from the foldable array in air, linear acoustic
reciprocity dictates that the findings may inspire new innovations for
acoustic receivers, e.g. adaptive sound absorbers and microphone arrays,
as well as concepts that include water-borne waves.
Biographies
Ryan L. Harne is an Assistant Professor in the Department of Mechanical
and Aerospace Engineering at The Ohio State University where he directs
the Laboratory of Sound and Vibration Research (LSVR). His research
expertise falls in the areas of vibration, acoustics, mechanics, and
nonlinear dynamics, with applications to noise and vibration control,
damping, and isolation; energy harvesting and guided energy transfer;
adaptive structural/material systems for properties and shape change; and
sensing methodologies and sensor development. Dr. Harne works include
several patents pending, one book, over 50 journal publications, and over
40 conference proceedings. Dr. Harne undertook undergraduate and
graduate work in the Department of Mechanical Engineering at Virginia
Tech (B.S. (2008), M.S. (2009), and Ph.D. (2012)). In 2008 he received a
Minor of Industrial Design from the Virginia Tech College of Architecture
and Design. From 2012 to 2015, Dr. Harne was a Research Fellow in the
Department of Mechanical Engineering at the University of Michigan. Dr.
Harne is an active Member of the Acoustical Society of America (ASA), the
American Society of Mechanical Engineers (ASME), and the International
Society for Optical Engineering (SPIE). He is an appointed member of the
ASA Technical Committee on Signal Processing in Acoustics, an elected
member of the ASME Technical Committee on Vibration and Sound, and
elected Chair of the ASME Technical Committee on Energy Harvesting. Dr.
Harne was awarded a 2017 Air Force Research Lab Summer Faculty
Fellowship, the 2017 ASME Best Paper Award in Structures and Structural
Dynamics, the 2016 Haythornthwaite Young Investigator Award from the
Applied Mechanics Division of ASME, and the 2011 ASA Royster Award for
noise control acoustics. He has served as Guest Associate Editor for the
ASME Journal of Vibration and Acoustics and the Journal of Intelligent
Material Systems and Structures, and currently serves as an Associate
Editor for The Journal of the Acoustical Society of America, Proceedings
of Meetings on Acoustics, in the Signal Processing in Acoustics technical
area.
Danielle T. Lynd is currently an Industrial Design Engineer at Norwood
Medical in Dayton, OH. Ms. Lynd completed her B.S. in Mechanical
Engineering at The Ohio State University in 2017. Ms. Lynd’s
undergraduate honors research was advised by Dr. Ryan L. Harne on the
research topic of origami-inspired acoustic transducer arrays. Ms. Lynd is
a recipient of a Best Paper Award during the 171st meeting of the
24 Acoustical Society of America (ASA) in 2016, and received the 2016 Robert
W. Young Award for Undergraduate Student Research in Acoustics from
ASA.
2017 BEST PAPER IN STRUCTURAL DYNAMICS AND CONTROL
M. Bodaghi, A. R. Damanpack, and W. H. Liao, 2016, “Self-expanding/
shrinking structures by 4D printing,” Smart Materials and Structures,
25(10): 105034.
M. Bodaghi
Chinese University of Hong Kong
A. R. Damanpack
Chinese University of Hong Kong
W. H. Liao
Chinese University of Hong Kong
Abstract
The aim of this paper is to create adaptive structures capable of self-
expanding and self-shrinking by means of four-dimensional printing
technology. An actuator unit is designed and fabricated directly by
printing fibers of shape memory polymers (SMPs) in flexible beams with
different arrangements. Experiments are conducted to determine
thermo-mechanical material properties of the fabricated part revealing
that the printing process introduced a strong anisotropy into the printed
parts. The feasibility of the actuator unit with self-expanding and self-
shrinking features is demonstrated experimentally. A phenomenological
constitutive model together with analytical closed-form solutions are
developed to replicate thermo-mechanical behaviors of SMPs. Governing
equations of equilibrium are developed for printed structures based on
the non-linear Green–Lagrange strain tensor and solved implementing a
finite element method along with an iterative incremental Newton–
Raphson scheme. The material-structural model is then applied to digitally
design and print SMP adaptive lattices in planar and tubular shapes
comprising a periodic arrangement of SMP actuator units that expand and
then recover their original shape automatically. Numerical and
experimental results reveal that the proposed planar lattice as meta-
materials can be employed for plane actuators with self-expanding/
shrinking features or as structural switches providing two different
dynamic characteristics. It is also shown that the proposed tubular lattice
with a self-expanding/shrinking mechanism can serve as tubular stents
and grippers for bio-medical or piping applications.