Seminars

PMMH’s weekly seminar is held every Friday at 11 am (map)

Contact :
Alice Pelosse
Stéphane Perrard
Etienne Reyssat
Virgile Thiévenaz
responsables-seminaires (arobase) pmmh.espci.fr

PMMH
BARRE CASSAN
BAT A 1ER ETAGE CASE 18
7 QUAI SAINT BERNARD
75005 PARIS
France

Tel : (33) 1 40 79 45 22


Séminaire PMMH – Émilien Dilly (LiPhy, Grenoble)

Vendredi 30 janvier de 11h00 à 12h00 - Salle réunion PMMH 1

Metabeams with programmable nonlinear bending response

Recent advances in mesoscale material architecture have enabled the design of structures exhibiting nonclassical mechanical responses, including auxetic behavior, mode coupling (e.g., stretching–bending and stretching–twisting), and exceptional stiffness-to-weight ratios. Inspired by the nonlinear bending response of a carpenter's measuring tape and the pronounced drooping of U-shaped plant petioles under water stress, we investigate the bending behavior of rectangular beams decorated with one or more longitudinal vertical fins.
During bending, longitudinal stretching of the fins couples to the beam curvature, inducing transverse compression within the fins. Beyond a critical curvature, this compression triggers fin buckling, which we rationalize in terms of the governing geometric parameters. Fin buckling leads to an abrupt reduction of the beam's effective moment of inertia, giving rise to a non-monotonic moment–curvature relationship closely analogous to that observed in carpenter's tapes.
By incorporating pillars that engage only beyond a prescribed curvature, we introduce curvature-dependent mechanical hardening. When combined with the fins, this strategy enables the programming of rich, highly tunable, and non-monotonic torque–curvature responses. An inverse design framework is developed to achieve on-demand torque profiles and is validated experimentally.
Exploiting this complex torque response, we further show that embedding fin-decorated beams into pneumatic bending actuators induces a snap-through instability, resulting in rapid actuation and a hysteretic mechanical response. This behavior enables fast, programmable motion.

Top







Seminars  (12)

Information for the speakers

The audience is composed of people with rather heterogeneous backgrounds including specialists in solids, fluids, granular flows, statistical physics... so the idea is to keep your talk understandable by people not necessarily working in your field... The seminar time slot runs from 11am to noon so the best is to make the talk last around 45 minutes to leave some time for discussion.

Link to cofee seminar (internal, every Thursday)


Top



Contact

Directeur : Ramiro GODOY DIANA
Codirecteur : Laurent DUCHEMIN
Administratrice : Frédérique AUGER (01 40 79 45 22)
Gestionnaire : Claudette BAREZ (01 40 79 58 53)
Courriel : dir (arobase) pmmh.espci.fr
Téléphone : 01 40 79 45 22
Adresse : PMMH UMR 7636 CNRS, ESPCI Paris-PSL, Sorbonne Université, Université Paris Cité
7 Quai Saint Bernard, Barre Cassan Bât A 1er étage Case 18, 75005 Paris