Characterization of Self-Folding Origami Structures Using Magneto-Active Elastomers

Sung, Elaine; Erol, Anil; Frecker, Mary; Lockette, Paris von

doi:10.1115/detc2016-59919

Cited by 6 publications

(4 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…MAE actuation can also be modeled using the FEA method by applying surface tractions on MAE patches with varying magnitudes as the patches rotate in spatial coordinate system, such as the models developed by Sheridan et al (2014), Sung et al (2016), and Zhang et al (2016). Haldar et al (2016) developed constitutive relations of magneto-active polymers to combine responses of both magnetic and mechanical systems by introducing Maxwell stress contributions to the free energy function.…”

Section: Introductionmentioning

confidence: 99%

Finite element analysis of electroactive and magnetoactive coupled behaviors in multi-field origami structures

Wei

Ahmed

Masters

et al. 2018

Journal of Intelligent Material Systems and Structures

Self Cite

View full text Add to dashboard Cite

Active origami-inspired designs, which incorporate active materials such as electroactive polymers and magnetoactive elastomers into self-folding structures, have shown good promise in engineering applications. In this article, finite element analysis models are developed for several bending and folding configurations that incorporate a combination of active and passive material layers, such as electroactive polymer-actuated unimorph benders based on single and multilayer electroactive polymers, electroactive polymer-actuated notched unimorph folding configurations, and a multi-field actuated bimorph configuration. Constitutive relations are developed for both electrostrictive and magnetoactive materials to model the coupled behaviors explicitly. Shell elements are adopted for their capacity of modeling thin films, relatively low computational cost, and ability to model the intrinsic coupled behaviors in the active materials under consideration. The electrostrictive coefficients are measured and then used as input in the constitutive modeling of the coupled behavior. The magnetization of the magnetoactive elastomer is measured and then used to calculate the magnetic torque as a function of the special orientation, which leads to spatial deformation of the magnetoactive elastomers. The objective of the study is to validate the constitutive models implemented through the finite element analysis method to simulate multi-field coupled behaviors of the active origami configurations. Through quantitative comparisons, simulation results show good agreement with experimental data. By investigating the impact of material selection, location, and geometric parameters, this finite element analysis approach can be used in design of self-folding structures, reducing trial-and-error iterations in experiments.

show abstract

Section: Introductionmentioning

confidence: 99%

Finite element analysis of electroactive and magnetoactive coupled behaviors in multi-field origami structures

Wei

Ahmed

Masters

et al. 2018

Journal of Intelligent Material Systems and Structures

Self Cite

View full text Add to dashboard Cite

show abstract

“…Hard magnets have been used to actuate self-folding because the magnetic torque is strong enough to generate large displacements, especially in compliant mechanisms [13,[23][24][25]. Magnetic torque is possible due to the anisotropic magnetic properties of hard magnets, which have a preferred magnetic direction determined by their magnetization.…”

Section: Magneto-active Structuresmentioning

confidence: 99%

Multi-objective optimization of a multi-field actuated, multilayered, segmented flexible composite beam

Erol

Lockette

Frecker

2019

Smart Mater. Struct.

Self Cite

View full text Add to dashboard Cite

Multi-layered, self-actuated devices have been the focus of recent studies due to their ability to exhibit large displacements and achieve complex shapes. Such devices have been constructed using active materials responsive to varying stimuli including electro-active and magneto-active materials to perform useful functions and achieve a wider variety of target shapes compared to single-field actuated unimorph/bimorph structures. However, fabrication of these devices for experimentation is time-consuming and expensive, which warrants the use of simulations as a means of designing high-performing structures. This work seeks to optimize structures employing materials response to magnetic and electric fields for multiple objective functions selected based on the needs of soft robotics applications such as grippers. A multi-objective optimization problem is constructed, utilizing a model developed for any arbitrary number of segments, layers, and material types, accommodating for large displacements and simultaneously applied fields. Three objective functions are chosen: (1) target shape approximation, based on the errors between the coordinates of the computed and desired shapes, (2) cost based on volume of magnetic material, and (3) work performed on a tip-force. The arbitrary optimization problem is reduced to a specific case study containing eight segments to alleviate the computational cost of an unwieldy number of parameters. The parameters are narrowed to: (1) segment lengths, (2) magnetic material in each magneto-active layer. The structure is pre-set to three material types: electro-active polymer, magneto-active elastomer, and a passive substrate. The case study's optimization problem is performed by a genetic algorithm developed by MATLAB for multiple objective functions. The results of the optimization on the case study are analyzed by studying the feasible designs on the Pareto front of the objective functions. Different trade-offs between objective functions are identified, and various feasible designs are found more suitable than others, based on the needs and priorities of an application.

show abstract

“…When bonded to a passive substrate, this MAE alignment can be used to create bending and folding. MAE has been used in the selffolding of an accordion geometry [29,38] as well as a bistable arch [9,39]. In both of these applications, an elastomer, namely, polydimethylsiloxane (PDMS), was used as the substrate upon which MAE was placed.…”

Section: Dynamic Modeling: Magneto-active Elastomermentioning

confidence: 99%

Design, Fabrication, and Modeling of an Electric–Magnetic Self-Folding Sheet

Bowen

Springsteen

Ahmed

et al. 2017

Journal of Mechanisms and Robotics

Self Cite

View full text Add to dashboard Cite

A concept recently proposed by the authors is that of a multifield sheet that folds into several distinct shapes based on the applied field, be it magnetic, electric, or thermal. In this paper, the design, fabrication, and modeling of a multifield bifold are presented, which utilize magneto-active elastomer (MAE) to fold along one axis and an electro-active polymer, P(VDF-TrFE-CTFE) terpolymer, to fold along the other axis. In prior work, a dynamic model of self-folding origami was developed, which approximated origami creases as revolute joints with torsional spring–dampers and simulated the effect of magneto-active materials on origami-inspired designs. In this work, the crease stiffness and MAE models are discussed in further detail, and the dynamic model is extended to include the effect of electro-active polymers (EAP). The accuracy of this approximation is validated using experimental data from a terpolymer-actuated origami design. After adjusting crease stiffness within the dynamic model, it shows good correlation with experimental data, indicating that the developed EAP approximation is accurate. With the capabilities of the dynamic model improved by the EAP approximation method, the multifield bifold can be fully modeled. The developed model is compared to the experimental data obtained from a fabricated multifield bifold and is found to accurately predict the experimental fold angles. This validation of the crease stiffness, MAE, and EAP models allows for more complicated multifield applications to be designed with confidence in their simulated performance.

show abstract

Characterization of Self-Folding Origami Structures Using Magneto-Active Elastomers

Cited by 6 publications

References 24 publications

Finite element analysis of electroactive and magnetoactive coupled behaviors in multi-field origami structures

Finite element analysis of electroactive and magnetoactive coupled behaviors in multi-field origami structures

Multi-objective optimization of a multi-field actuated, multilayered, segmented flexible composite beam

Design, Fabrication, and Modeling of an Electric–Magnetic Self-Folding Sheet

Contact Info

Product

Resources

About