Ultra-thin composites membrane for deployable structures: XCT driven characterization and FE modeling of folding structure

Light-weight, ultra-thin, high performance, origami-inspired deployable folding structures can be fabricated by simulating various designs and material combinations. In this study, an XCT-driven finite element (FE) model of a building block in a typical full-scale origami structure consisting of stiff and fold regions was developed. Following our previous work, the stiff region of the fold sample was fabricated using a hot compression molding technique whereas hand layup was employed for the fold region. XCT-driven FE based homogenization was carried out on an RVE of real microstructure of both ultra-thin composite laminates. The FE homogenization results were found to be in good agreement with the experimentally-measured effective stiffness properties of both the stiff and fold regions, with a maximum error of ∼10%. Folding tests were conducted on a simple fold and the force vs. displacement and moment vs. curvature curves were plotted. The applicability of XCT-driven FE modeling to simulate foldable structures were demonstrated using post-buckling and bending analysis available in the FE software ABAQUS®. A uniform and symmetric fold curvature, along with the corresponding force vs. displacement response were predicted using XCT-driven FE techniques and found to be in good agreement with data from the experimental tests. The peak force predicted by the FE model showed an error of ∼5.2% compared to the experimental fold test.