Dynamics of an impact oscillator with SMA constraint

Abstract

The dynamic behaviour of an impact oscillator with an SMA constraint has been modelled and analysed. Following the formulation proposed by Bernardini and his co-authors [1,2] describing thermo-mechanics of SMA elements, we obtain a compact thermo-mechanical model of an impact pseudoelastic oscillator. Due to the mechanical characteristics of SMA element and non-smooth nature of the impacts, five different modes of operation can be distinguished for this system. The undertaken numerical investigation suggests that the system can exhibit complex dynamic responses which if appropriately controlled can be used for vibration reduction. For this reason alone a comparison with an equivalent elastic oscillator was made. It was found out that low amplitude regimes are not affected by the presence of SMA element. On contrary, for the large amplitude responses a significant vibration reduction was achieved due to the phase transformations.