  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.
