This dataset contains all data as used for the paper 'Viscoelastic Snapping Metamaterials', as published in the Journal of Applied Mechanics.
Abstract:
Mechanical metamaterials are artificial composites with tunable advanced mechanical properties. Particularly, interesting types of mechanical metamaterials are flexible metamaterials, which harness internal rotations and instabilities to exhibit programable deformations. However, to date, such materials have mostly been considered using nearly purely elastic constituents such as neo-Hookean rubbers. Here, we experimentally explore the mechanical snap-through response of metamaterials that are made of constituents that exhibit large viscoelastic relaxation effects, encountered in the vast majority of rubbers, in particular, in 3D printed rubbers. We show that they exhibit a very strong sensitivity to the loading rate. In particular, the mechanical instability is strongly affected beyond a certain loading rate. We rationalize our findings with a compliant mechanism model augmented with viscoelastic interactions, which qualitatively captures well the reported behavior, suggesting that the sensitivity to the loading rate stems from the nonlinear and inhomogeneous deformation rate, provoked by internal rotations. Our findings bring a novel understanding of metamaterials in the dynamical regime and open up avenues for the use of metamaterials for dynamical shape-changing as well as vibration and impact damping applications.
Notes
Written by David Dykstra (28/08/2019)
This is the readme file for the Replication package of the article:
"Viscoelastic Snapping Metamaterials"
David M.J. Dykstra , Joris Busink , Bernard Ennis & Corentin Coulais
Journal of Applied Mechanics, JAM-19-1166 (2019)
The Replication package consists of:
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* Figures_and_Data
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This folder contains all data used to replicate the figures and data used in the article. All subfolders are directly structured per figure, as mentioned in the subsubfolder titles. The subfolders are structured as follows:
*RAW_Data:
-Contains all experimentally obtained RAW_Data, used to generate:
> Figure2: Used to generate Figure 2
> Figure3-4: Used to generate Figure 3 and Figure 4
*PostProcessingCodes:
-Contains all Python codes that are used to process RAW_Data, generate numerical data, generate intermediate data and process this data to obtain the Final Data used to plot the figures.
> Figure2: Fig2_PostProcessingCode_01.py processes the Figure2 RAW_Data to obtain the Figure 2 Final Data
> Figure3-4: Processes the experimental Figure3-4 RAW_Data to obtain the Figure 3 and 4 Intermediate and Final Data. Have to be run in the following order:
# Fig3-4_IntermediateResultsGeneration_Part01_Instron.py
# Fig3-4_IntermediateResultsGeneration_Part02a_Movies_Main.py
# Fig3-4_ResultsGeneration_Part03.py
> Figure5-6: Generates the numerical intermediate and final data to obtain Figure 5 and 6. Have to be run in the following order:
# Fig5-6_ResultsGeneration_Part01.py
# Fig5-6_ResultsGeneration_Part02.py
> Figure7: Generates the numerical intermediate and final data to obtain Figure 7. Have to be run in the following order:
# Fig7ab_ResultsGeneration_Part01.py
# Fig7ab_ResultsGeneration_Part02.py
# Fig7cd_ResultsGeneration_Part01.py
# Fig7cd_ResultsGeneration_Part02.py
*IntermediateData:
-Contains data in various formats generated by the scripts mentioned in "PostProcessingCodes", which are used by other scripts in "PostProcessingCodes" to obtain the results in "FinalData".
*FinalData:
- Contains for each figure employing graphs (Figures 2-7), the plotted data in .csv format, generated by the scripts in "PostProcessingCodes". If a figure contains subfigure (a,b,c etc.), the data in each subfigure is contained in a single .csv file titled "Fig**_FinalData.csv", where ** indicates the (sub)figure ID.
- Each .csv file is structured into the following columns: [Index, x-data - Line 1, y-data - Line 1, x-data - Line 2, y-data - Line 2, ...].
*FinalFigureGenerationCodes:
- Contains for each figure employing graphs (Figures 2-7), the python script processing the data in "FinalData" to the .pdf Final Figures in "FinalFigures".
- Folders "RAW_Data", "PostProcessingCodes" and "IntermediateData" are not necessary to run these codes, only the data in "FinalData"
*FinalFigures:
- Contains the .pdf files generated by the codes in "FinalFigureGenerationCodes"
- Contains the final figures "Fig*.eps", employed in the article where * is the figure ID used in the article, employing the .pdf files mentioned previously. The .eps files further employ non numerical images directly and have been generated using Adobe Illustrator CC 2019.
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* ViscoelasticSnappingMetamaterials
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- This folder contains the latex source code to generate the preprint of the article, titled 'Paper.pdf'.
- With the figures "Fig*.eps" in "FinalFigures" copied to "ViscoelasticSnappingMetamaterials/figure".
