Lightweight compliant surfaces are commonly
used as roofs (awnings), filtration systems or propulsive appendages,
that operate in a fluid environment. Their flexibility allows for shape
to change in fluid flows, to better endure harsh or fluctuating
conditions, or enhance flight performance of insect wings for example.
The way the structure deforms is however key to fulfill its function,
prompting the need for control levers. In this talk, we will consider
two ways to tailor the deformation of surfaces in a flow, making use of
the properties of origami (folded sheet) and kirigami (sheet with a
network of cuts). Previous literature showed that the substructure of
folds or cuts allows for sophisticated shape morphing, and produces
tunable mechanical properties. We will discuss how those original
features impact the way the structure interacts with a flow, through
combined experiments and theory. We will notably show that a sheet with a
symmetric cutting pattern can produce an asymmetric deformation, and
study the underlying fluid-structure couplings to further program shape
morphing through the cuts arrangement. We will also show that extreme
shape reconfiguration through origami folding can cap fluid drag.
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