## Kirigami Design and Analysis

Design and mechanical analysis of Kirigami structures

You must login before you can run this tool.

Version 1.0 - published on 28 Jan 2019

doi:10.21981/98HE-V722 cite this

## Tool Description

A short video tutorial is available here: GamIan Tutorial

GAMIAN is a design and mechanical ANalysis tool for KiriGAMI structures. Starting from designing cuts or incisions on any thin-film structure to solving for its final deformed configuration under planar loading, all the steps can be carried out using GAMIAN. GAMIAN provides functionalities to select material, define the Kirigami geometry, perform meshing, and numerically solve for the deformation response using the nonlinear finite-element method. Using these capabilities, a user can iterate over the choice of materials and geometric dimensions and cut-patterns and achieve the desired deformation pattern of a Kirigami structure.

## A Quick How-to

The response of a kirigami structure under stretching deformation can be simulated using the following basics steps:

• Select a material in the ‘Material’ tab
• The default material is Polyimide.
• To try a different material (that can be modeled using elastoplastic constitutive law)
• Fill out the material properties fields and…
• To review the stress-strain relation of the material, hit the ‘Show material’ button under ‘Preliminary Plots’
• Define the geometry parameters in the ‘Geometry’ tab referring to the ‘Geometry Layout Reference’
• Set the dimensions of the rectangular Kirigami sheet
• Set the dimensions and the number of notches on the planar surface of the sheet
• For the 2D view of the final Kirigami structure, hit the ‘Show geometry’ button under ‘Preliminary Plots’.
• Generate the mesh in the Mesh tab.
• There are settings to refine the size and resolution, a mesh setting of (no. of seg=1, size=0.2) tend to work well and limit run times to < 20min.
• When satisfied with the geometry and mesh setting, go ahead and hit “Generate Mesh”.
• Execute the simulation in the Simulation tab.
• Click the “Run pre-check” button.  This will check that all the required files are in place to run the finite element simulation.
• Click the “Run Simulation” button
• Review Results
• After the simulation completes you should see a line like: “Last Run: OK. Run Time: 00:xx:xx”.
• geom_kiri.step: Geometry file
• geom_kiri.step: Geometry file
• DXDYDZ_kiri.resu: Displacement result file
• vmisTresca_kiri.resu: Stress result file
• sigXXYYZZ_kiri.resu: Stress result file
• viz_kiri.rmed: Result file readable by ParaVIS module in Salome-Meca
• mesg_kiri.mess: Message file logging details of a simulation run

## Background

Kirigami (‘kiri’- cut, ‘gami’- paper), an ancient art of paper cutting, offers a structural design platform to yield unconventional mechanical and morphological responses by tuning the stiffness and deformation behaviors of the underlying material. Strategic kirigami incisions or notches applied on 2D precursor can enable the creation of highly deformable devices while maintaining the functional components strain-free, thereby offering significant implications for stretchable/reconfigurable electronics and soft robotics. As kirigami features yield geometric deformations that dominate the inherent material elasticity, the properties and structures of kirigami metamaterials can be controlled by the pattern and orientation of the incisions and notches. Under mechanical loading/stretching, 2D kirigami surface architectures morph into three-dimensional (3D) structures in the vicinity of patterned regions owing to buckling and mechanical bi-stability. GAMIAN can be used to predict the final morphology of a kirigami structure for a given choice of material and cut-patterns, and thereby optimize those parameters to achieve the desired morphology.