0
Research Papers

Design and Optimization of a Shape Memory Alloy-Based Self-Folding Sheet

[+] Author and Article Information
Edwin Peraza-Hernandez

e-mail: eperaza@neo.tamu.edu

Darren Hartl

e-mail: darren.hartl@tamu.edu
Department of Aerospace Engineering,
Texas A&M University,
College Station, TX 77843

Edgar Galvan

e-mail: e_galvan@tamu.edu

Richard Malak

e-mail: rmalak@tamu.edu
Design Systems Laboratory,
Department of Mechanical Engineering,
Texas A&M University,
College Station, TX 77843

1Corresponding author.

Contributed by the Design Automation Committee of ASME for publication in the JOURNAL OF MECHANICAL DESIGN. Manuscript received February 11, 2013; final manuscript received June 28, 2013; published online October 3, 2013. Assoc. Editor: Mary Frecker.

J. Mech. Des 135(11), 111007 (Oct 03, 2013) (11 pages) Paper No: MD-13-1078; doi: 10.1115/1.4025382 History: Received February 11, 2013; Revised June 28, 2013

Origami engineering—the practice of creating useful three-dimensional structures through folding and fold-like operations on two-dimensional building-blocks—has the potential to impact several areas of design and manufacturing. In this article, we study a new concept for a self-folding system. It consists of an active, self-morphing laminate that includes two meshes of thermally-actuated shape memory alloy (SMA) wire separated by a compliant passive layer. The goal of this article is to analyze the folding behavior and examine key engineering tradeoffs associated with the proposed system. We consider the impact of several design variables including mesh wire thickness, mesh wire spacing, thickness of the insulating elastomer layer, and heating power. Response parameters of interest include effective folding angle, maximum von Mises stress in the SMA, maximum temperature in the SMA, maximum temperature in the elastomer, and radius of curvature at the fold line. We identify an optimized physical realization for maximizing folding capability under mechanical and thermal failure constraints. Furthermore, we conclude that the proposed self-folding system is capable of achieving folds of significant magnitude (as measured by the effective folding angle) as required to create useful 3D structures.

FIGURES IN THIS ARTICLE
<>
Copyright © 2013 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 1

Demonstration of the reconfigurable self-folding concept. A sheet with no pre-engineered folds is deformed along a set of lines as determined by heating location only.

Grahic Jump Location
Fig. 2

Schematics of film and mesh design (aligned and staggered meshes) for foldable sheets

Grahic Jump Location
Fig. 3

Schematic of the folding sheet model showing boundary conditions

Grahic Jump Location
Fig. 4

Smooth thermal load profile

Grahic Jump Location
Fig. 5

Schematic of the mesh-based folding sheet showing input parameters

Grahic Jump Location
Fig. 6

Schematic of effective sheet lift angle ϕ

Grahic Jump Location
Fig. 7

Partial scatter-plot matrix demonstrating the relationship among the design variables and output parameters taken two at a time. The relationship between the design variables themselves is not shown. Only feasible designs are reported in the plots.

Grahic Jump Location
Fig. 8

Partial DOE results. The solid line in each subplot indicates the Pareto frontier in the case where the decision maker is only considering the parameters indicated on the subplot axes. It is assumed that the decision maker prefers to minimize R, σmax and TmaxSMA, and θ. Only feasible designs are reported in the plots.

Grahic Jump Location
Fig. 9

Contour plot of the minimum achieved θ (deg) as a function of wire thickness and elastomer thickness

Grahic Jump Location
Fig. 10

Contour plot of the minimum achieved R (m) as a function of P and TmaxSMA

Grahic Jump Location
Fig. 11

Optimized folding sheet configurations at the end of the heating period. Input and output parameters for this model are presented in Table 4. The contour plots show temperature and martensitic volume fraction. The symmetric and periodic analysis domain (Fig. 3) has been mirrored and patterned for the sake of visualization.

Grahic Jump Location
Fig. 12

Evolution in effective folding angle θ for the compound folds case study

Grahic Jump Location
Fig. 13

Folding sheet configurations at different times during the multiple folding operations. The contour plots show temperature and martensitic volume fraction. The symmetric and periodic analysis domain (Fig. 3) has been mirrored and patterned for the sake of visualization.

Grahic Jump Location
Fig. 14

Evolution of folding angle with time for the staggered mesh design and the aligned mesh design

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In