Expérimental
Context. The laws of linear elasticity rely on the assumption that deformations should remain small. For conventional solids, this is usually true. For soft solids (polymers, rubbers, gels ...) however, a moderate stress can induce a significant strain, meaning that nonlinear events are likely to occur. Objectives. Thanks to optical detection methods, we will track nonlinear phenomena in simple flexible structures [1]. Starting from a soft beam undergoing a parametric forcing, we will look for signatures of instable behaviors [2]. Soft polymers can easily be molded in different shapes which will allow us to explore a variety of configurations. As a possible direction, one could load the elastic structure with iron magnetic particles in order to monitor its mechanical properties with an external magnetic field [3]. This system also provides a new platform to investigate nonlinear wave-wave interaction in the context of elastic fields [4]. Perspectives. Understanding the motion of soft structures is crucial for applications ranging from energy harvesting to soft robot’s actuation. The implementation of a nonlinear self-propelled robot prototype will be considered. contact: M. LANOY maxime.lanoy@univ-lemans.fr F. PETRELIS petrelis@phys.ens.fr