Damping adjustment of a nonlinear vibration absorber using an electro-magnetomechanical coupling

Vibration absorbers are known for their use in vibration mitigation. In particular, nonlinear vibration absorbers have been of great interest for vibratory level reduction as they do not have to be tuned to the natural frequency of their supporting structure. In order to obtain satisfactory operations of the absorber (energy necessary for its activation and dissipated vibratory level), it is necessary to identify the correct parameters of the absorber which are its nonlinear stiffness and damping. However, when moving from analytics to designing an experimental prototype, it is complicated to have the appropriate parameter values, especially damping, because it is very difficult (or even impossible) to adjust a precise value for a mechanical assembly. As a consequence, this bad adjustment leads to an inefficiency of the absorber and unsatisfactory results. To avoid this lack of robustness, the addition of a multiphysical coupling, to a nonlinear absorber is studied in this paper in order to create an equivalent damping coefficient from another nature: electro-magnetomechanical. This new damping generated is adapted and allows to adjust the equivalent damping coefficient of the absorber to get the best efficiency, analytically and experimentally.