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arXiv · 1805.07201

Asymptotic self-restabilization of a continuous elastic structure

F. Bosi·D. Misseroni·F. Dal Corso·S. Neukirch·D. Bigoni
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Abstract

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.

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F. Bosi, D. Misseroni, F. Dal Corso, S. Neukirch, D. Bigoni. 2018-05-05. Asymptotic self-restabilization of a continuous elastic structure. https://doi.org/10.1103/physreve.94.063005

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