Charlotte Py 2026-11-05
Charlotte Py has investigated elasto-capillarity, including how surface tension deforms an elastic sheet. She is the first author of the 2007 study introducing capillary origami: spontaneous wrapping of a liquid droplet by a flexible sheet.[ref]
Capillary Origami: Spontaneous Wrapping of a Droplet with an Elastic Sheet by Charlotte Py and others. Page156103-1: full author byline, problem and experiments
The experiment used thin polydimethylsiloxane sheets cut into different shapes. As water evaporated, surface tension progressively curved the sheet around the diminishing droplet. Square and triangular cuts followed different folding sequences, while sufficiently small or stiff sheets reopened rather than completely enclosing the liquid. This connected an accessible observation with a competition between surface energy and elastic bending.[ref]
Capillary Origami: Spontaneous Wrapping of a Droplet with an Elastic Sheet by Charlotte Py and others. Pages156103-1–2; Figure1: wrapping sequences and reopening comparison
A complementary loop experiment measured the elastocapillary length: a wetting meniscus held a long strip in a loop whose shape could be compared with an elastic calculation. The resulting length scale helped organize the threshold for enclosure across sheet thicknesses and geometries.[ref]
Capillary Origami: Spontaneous Wrapping of a Droplet with an Elastic Sheet by Charlotte Py and others. Page156103-2; Equation1 and Figure2: characteristic length and loop calibration