@article {63,
	title = {Rods coiling about a rigid constraint: Helices and perversions},
	journal = {Proceedings of the Royal Society A},
	volume = {477},
	year = {2021},
	pages = {20200817},
	abstract = {<p align="justify">Mechanical instabilities can be exploited to design innovative structures, able to change their shape in the presence of external stimuli. In this work, we derive a mathematical model of an elastic beam subjected to an axial force and constrained to smoothly slide along a rigid support, where the distance between the rod midline and the constraint is fixed and finite. Using both theoretical and computational techniques, we characterize the bifurcations of such a mechanical system, in which the axial force and the natural curvature of the beam are used as control parameters. We show that, in the presence of a straight support, the rod can deform into shapes exhibiting helices and perversions, namely transition zones connecting together two helices with opposite chirality. The mathematical predictions of the proposed model are also compared with some experiments, showing a good quantitative agreement. In particular, we find that the buckled configurations may exhibit multiple perversions and we propose a possible explanation for this phenomenon based on the energy landscape of the mechanical system.</p>},
	keywords = {bifurcation theory, elastic rods, finite-element simulations, helices, perversions, weakly nonlinear analysis},
	doi = {/10.1098/rspa.2020.0817},
	author = {Davide Riccobelli and Giovanni Noselli and Antonio DeSimone}
}
@article {38,
	title = {A robotic crawler exploiting directional frictional interactions: Experiments, numerics and derivation of a reduced model},
	journal = {Proceedings of the Royal Society A},
	volume = {470},
	year = {2014},
	pages = {20140333},
	abstract = {<p align="justify">We present experimental and numerical results for a model crawler which is able to extract net positional changes from reciprocal shape changes, i.e. {\textquoteleft}breathing-like{\textquoteright} deformations, thanks to directional, frictional interactions with a textured solid substrate, mediated by flexible inclined feet. We also present a simple reduced model that captures the essential features of the kinematics and energetics of the gait, and compare its predictions with the results from experiments and from numerical simulations.</p>},
	keywords = {breathing-like deformations, crawling motility, directional interactions, directional surfaces, scallop theorem},
	doi = {10.1098/rspa.2014.0333},
	author = {Giovanni Noselli and Antonio DeSimone}
}
