Diego Misseroni, Sébastien Neukirch, Davide Bigoni, F. Bosi, F. Dal Corso, Dipartimento di Ingegneria Civile Ambientale e Meccanica [Trento] (DICAM), Università degli Studi di Trento (UNITN), Mécanique et Ingénierie des Solides Et des Structures (IJLRDA-MISES), Institut Jean le Rond d'Alembert (DALEMBERT), and Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)
A challenge in soft robotics and soft actuation is the determination of an elastic system which spontaneously recovers its trivial path during postcritical deformation after a bifurcation. The interest in this behaviour is that a displacement component spontaneously cycles around a null value, thus producing a cyclic soft mechanism. An example of such a system is theoretically proven through the solution of the Elastica and a stability analysis based on dynamic perturbations. It is shown that the asymptotic self-restabilization is driven by the development of a configurational force, of similar nature to the Peach-Koehler interaction between dislocations in crystals, which is derived from the principle of least action. A proof-of-concept prototype of the discovered elastic system is designed, realized, and tested, showing that this innovative behaviour can be obtained in a real mechanical apparatus., 11 pages, 8 figures