Optimized modal synchronized switching control for flexible structures

This paper focuses on the Synchronized Switching Damping (SSD) control, a semi-active vibration suppression technique based on the coupling between a mechanical structure and piezoelectric actuators. This control family is optimized for structures subjected to mono-harmonic excitation. Anyway, in the last years, different solutions to address multi-harmonic and multi-modal excitation have been developed. One of them is the so-called Modal SSD, where the switches of the shunting circuit are governed by the behavior of the modal coordinates of the structure. Although the control performance is good, this paper shows that there are still some issues to be solved. For this reason, the paper proposes a modified version of this control strategy able to improve the control performance without increasing the circuit complexity. The proposed solution is firstly described in detail and then tested and compared with the existing ones on the numerical model of a cantilever beam.