A broadband semi passive piezoelectric technique for structural damping

The damping of vibration resonance is a crucial problem for light and elongated structures. Different kinds of solutions have been developed in order to address the problem of volume or mass, or temperature dependence which are common to the passive approach. In the semi-passive technique proposed here, damping is obtained through the use of piezoelectric patches bonded on the structure. These piezoelements are controlled with a very simple approach only requiring switches which are driven periodically and synchronously with the structure motion. The overall control circuit requires a very few amount of energy. Results obtained on a beam and on a plate demonstrate that this self-adaptive technique is able to control simultaneously different modes on a broad frequency range.