Topology and Shape Optimization of Ultrathin Composite Self-Deployable Shell Structures with Cutouts

Abstract

The paper presents topology optimization studies of selfs-deployable joints in thin-walled tubular structures. The joints are made entirely of ultra-thin, fiber reinforced composite materials. The objective of this research is to strategically position cutouts on the joints so that they can fold without failing, while maximizing the deployed bending stiffness. The optimal shape and position of cutouts are the results of concurrent topology optimization of these composite, thin-shell joints with geometrical non-linearities, due to their folding and self-deployable nature. Numerical methods to accurately detect failure are implemented and results from a novel level-set method for topology optimization are compared to results from classical parametric optimization and preliminary designs based on physical intuition.

Effective continuum models for the buckling of non-periodic architected sheets that display quasi-mechanism behaviors

“…We note that the implicit relation (7) does not define the function g(C, ϕ) uniquely, implying that other choices of the functions Ψ p from (12) and Ψ m from (13) are possible. A good agreement with experiments is still attained, suggesting that the buckling behavior of the sheet is robust with respect to the choice of the function g. In principle, the effective elasticity parameters λ, µ, η and B are functions of the geometric parameters and would vary in space if not for the fact that l 1 , l 2 and δ are constant throughout the sheets, yielding a uniform spatial distribution of joints.…”

“…where J = √ det(C), Ī1 = tr(C)J −1 , µ and λ are the Lamé parameters and Ψ p is given in (12). Our bending energy density functions is…”

“…These fabrication processes have considerably expanded the design space for shape-shifting media [5][6][7] and deployable structures [8,9]. In this context, mesoscale design has been used to create compliant features that replace conventional hinges, extensional elements and flexures [10][11][12], or to create structures whose mechanical behaviors can be tailored by adjusting the geometry of a pattern [13][14][15][16][17][18][19][20][21].…”

A neural network-informed self-aware deployable structure with application to phased array antennas

“…The preparation of these particular composite hinges has been described previously along with their positioning performance with integrated actuators [9,23]. It should be noted that the current work can be implemented on many other deployable structures as well as with varying types of hinge mechanisms [24][25][26][27][28]. The deploy and stow of the structure is controlled by hand, and is stowed and deployed on the order of 15 s for each.…”

Roll-Out Deployment Process Analysis of a Fiber Reinforced Polymer (FRP) Composite Tape-Spring Boom

“…Pellegrion from Caltech investigated a bistable cylindrical shell, and a comprehensive analytical model was developed which could predict the residual stress distribution and bistable configurations of the shell [8][9][10]. Further, Pellegrino also concentrated on the analysis of multi-stable morphing structures, for instance, self-deployable shells, in the recent work for extending the applications of the FRP composite materials [11][12][13].…”