Abstract
Pantographic metamaterial design benefits from model identification procedures starting from what can be considered as the elementary unit cell of larger pantographic structures. Results from a tensile experiment and digital image correlation are utilized to identify the constitutive parameters of a discrete Hencky-type model for a millimetric pantographic cell. In the performed calibration, two different cost functions are formulated. First, the cost function is based upon measured resultant forces on the specimen boundaries. Then, the second cost function is based upon the measured pivot displacements in addition to reaction forces. The second cost functions thus exploits the pivot kinematics, which is a key feature of the deformation of pantographic structures. The identified model is further validated by predicting the reaction forces and pivot displacements of the same specimen subjected to compression. It is shown that the identification with the cost function incorporating pivot displacements is superior. It is also noted that the calibrated parameters deviate considerably from their initial guess derived from the linear Saint Venant problem, thereby indicating microscale nonlinear affects in otherwise linear reaction force-prescribed displacement responses at the macroscale.
Original language | English |
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Article number | 104419 |
Journal | International Journal of Non-Linear Mechanics |
Volume | 153 |
DOIs | |
Publication status | Published - Jul 2023 |
Bibliographical note
Publisher Copyright:© 2023 Elsevier Ltd
Funding
This work was partially funded by CNRS/IRP Coss&Vita between Fédération Francilienne de Mécanique (F2M, CNRS FR2609 ) and M&MoCS.
Funders | Funder number |
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IRP Coss&Vita between Fédération Francilienne de Mécanique | FR2609 |
Centre National de la Recherche Scientifique |
Keywords
- Digital image correlation
- Discrete model
- Inverse analysis
- Pantographic structures