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Awards

EPHRAHIM GARCIA BEST PAPER AWARD ASME ASMS TC 2016 BEST PAPER AWARD
This ASMS award was established in memory of Professor Garcia’s
extraordinary contributions in scholarship, education, and service to the There are two best-paper awards established by the ASME Adaptive
field of smart materials and adaptive structures. Structures and Materials Systems Technical Committee (ASMS TC): 1)
Structural Dynamics and Control Best Paper Award and 2) Materials and
2016 Ephrahim Garcia Best Paper Award Systems Best Paper Award. Papers published in journal publications
G. Wang, N. Wereley, T. Pillsbury, “Nonlinear Quasi-Static Model of relevant to smart materials and structures and conference proceedings
Pneumatic Artificial Muscle Actuators,” Journal of Intelligent Material sponsored by the ASMS committee are eligible for the best-paper
Systems and Structures. 26(5), 541-553, 2015 competition. Nominated papers are sent out for review. The winners of this
year’s awards are listed below.

Gang Wang 2016 Best Paper in Structural Dynamics and Control
University of Alabama Suyi Li and K. W. Wang, “Fluidic origami: a plant-inspired adaptive
structure with shape morphing and stiffness tuning,” Smart Materials and
Structures, 24(10), 2015.

Suyi Li
Norman M Wereley Clemson University
University of Maryland

Kon-Well Wang
Thomas Pillsbury University of Michigan
University of Maryland

Abstract
Inspired by the physics behind the rapid plant movements and the rich
Abstract topologies in origami folding, this research creates a unique class of
Pneumatic artificial muscles are a class of pneumatically driven actuators multi-functional adaptive structure through exploring the innovation of
that are remarkable for their simplicity, lightweight, high stroke, and high fluidic origami. The idea is to connect multiple Miura folded sheets along
force. The McKibben artificial muscle, which is a type of pneumatic artificial their crease lines into a space-filling structure, and fill the tubular cells
muscle, is composed of an elastomeric bladder, a braided mesh sleeve, in-between with working fluids. The pressure and fluid flow in these cells
and two end fittings. Gaylord first developed an analysis of the McKibben can be strategically controlled much like in plants for nastic movements.
artificial muscle based on the conservation of energy principle. The The relationship between the internal fluid volume and the overall
Gaylord model predicts block force but fails to accurately capture structure deformation is primarily determined by the kinematics of folding.
actuation force versus contraction ratio behavior. To address this lack, a This relationship can be exploited so that fluidic origami can achieve
non-linear quasi-static model is developed based on finite strain theory. actuation/morphing by actively changing the internal fluid volume, and
The internal stresses in the bladder are determined by treating it as a stiffness tuning by constraining the fluid volume. In order to characterize
cylinder subjected to applied internal pressure and a prescribed kinematic the working principles and performance potentials of these two adaptive
constraint of the outer surface. Subsequently, the force balance approach functions, this research develops an equivalent truss frame model on a
is applied to derive the equilibrium equations in both the axial and fluidic origami unit cell to analyze its fundamental elastic characteristics.
circumferential directions. Finally, the closed-form pneumatic artificial Eigen-stiffness analysis based on this model reveals the primary modes of
muscle quasi-static actuator force is obtained. The analysis was experi- deformation and their relationships with initial folding configurations.
mentally validated using actuation force versus contraction ratio test data Performances of the adaptive functions are correlated to the crease
at a series of discrete inflation pressures for two different pneumatic pattern design. In parallel to analytical studies, the feasibility of the
artificial muscles: a large pneumatic artificial muscle (L = 128.5 mm, B = 7.85 morphing and stiffness tuning is also examined experimentally via a 3D
mm, with a latex bladder) and a miniature pneumatic artificial muscle (L = printed multi-material prototype demonstrator. The research reported in
43.9 mm, B = 2.3 mm, with a V330 elastomeric bladder). this paper could lead to the synthesis of adaptive fluidic origami cellular
metastructures or metamaterial systems for various engineering
applications.

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