Jeudi 4 Juillet 2024 à 11h — 3ème séminaire de la série à l'IRPHE
4 Juillet 2024 à 11h — Bouncing Stars and Snapping Rods
Abstract: I will discuss two seemingly disparate problems: snap-through instabilities in elastic rods and gait transitions from crawling to bouncing in sea stars. Symmetries and symmetry-breaking provide a general motif for explaining these transitions. They can guide future design of functional metamaterials, and, in sea stars, help to decipher the hierarchical organization of distributed mechanosensing and control in locomotion and cooperative transport.
28 Mai 2024 à 11h — Ciliary Carpets and Flames
Abstract: Motile cilia are basic microactuators in cell biology that beat cyclically to transport fluid across the cell surface. They serve diverse biological functions from locomotion and feeding in microorganisms to transport of luminal fluids in higher organisms, including humans. Here, I will discuss the organization of ciliated organs from a physics perspective, whereby I attempt to untangle the intricate interplay between morphology, activity, and mechanics that lead to robust biological function. I will comment on the broad implications of this work to areas ranging from marine ecology to human health.
20 Juin 2024 à 11h — Collective Phase Transitions in Confined Fish Schools
Abstract: I will discuss action-perception cycles in fish and robots that enable (i) navigation in unsteady flows and (ii) emergent collective patterns. In confined fish groups, I will show intermittent collective modes that switch back-and-forth between schooling and milling and analyze the underlying bifurcations by mapping the stochastic dynamics of fish onto a Fokker-Planck equation that governs the group dynamics. Our work establishes promising directions for learning, from a fish- or robot-centric perspective, in a dynamically changing physical environments and opens avenues for investigating the mapping between environmental conditions and sensory requirements in biological systems.
Eva Kanso / Professor of Aerospace and Mechanical Engineering, University of Southern California