Impact of damping factor on the effectiveness of an energy harvesting vibration absorber

Vibration absorbers are usually used to reduce the vibration of mechanical systems. On the other hand, the vibration can also excite piezoelectric transducers for mechanical-to-electrical energy conversion in order to have self-powered sensors. The transducers can be integrated in the structure of the absorber obtaining an energy harvesting vibration absorber (EHVA). Nevertheless, despite the structures of absorber and of energy harvester can be very similar, the parameters necessary to design optimal devices are usually different. In particular, the requirements about the damping are in contrast. In this work the impact of the EHVA damping on the effectiveness of vibration reduction and power generation has been investigated in simulation and experimentally. A test rig with adjustable damping via an active control has been set up for experimental validation. A voltage driven voice coil actuator has been used for this purpose with a relative velocity feedback control.