Resumen de Snap-through analysis of multistable laminate using the variational asymptotic method
A. Phanendra Kumar, Dineshkumar Harursampath, Vinyas Mahesh, Ramesh Gupta Burela, Shaikbepari Mohmmed Khajamoinuddin
Multistable laminates have attracted the attention of researchers for developing morphing structures, as they can stay in different stable configurations without any need for external forces to maintain any of those configurations. In this study, a novel application of a reconfigurable antenna made with rectangular composite laminates [90/0] in the shape of a star is analyzed using the Variational Asymptotic Method (VAM), which is free of ad-hoc assumptions and highly accurate, unlike semi-analytical theories present in the literature. The star shaped laminate is modeled as a plate using geometrically exact kinematics, and thermal analysis is done by applying uniform temperature to obtain its cool-down shape, which shows multistability. Snap-through forces are applied on the structure to change to the other stable configurations. Three parametric studies are performed to identify the variation of snap-through force. These studies are carried out by varying the aspect ratio, curing temperature, and thickness of the individual rectangular laminates to identify the lower and upper limits beyond which the laminate loses its multistability. All studies performed using VAM are validated against 3D FEA in ABAQUS are found to be in good agreement with each other although, VAM handled the 3D problem at the 2D level achieved by systematic dimensional reduction. The computational efficiency is found to increase by almost 70% compared to 3D FEA.
