Experimental Study of an Energy Harvesting Beam-Tuned Mass Damper

Abstract

The previous chapter has introduced, and investigated theoretically, the concept of an electromechanically tuned vibration absorber (TVA —or, more specifically, tuned mass damper, TMD). This device was formed from two symmetric dual-function TMD/energy-harvesting beams which were suitably shunted in order to attenuate a vibration mode of a generic structure. The analytical modal analysis method (AMAM) and the dynamic stiffness method (DSM) were used to derive the frequency response functions (FRFs) of the host structure with the attached TMD beams shunted across different circuit configurations. Simulations predicted that through the correct tuning of the R-L-C parameters, the electromechanical TMD was capable of producing a response that very closely replicated the benchmark response of an equivalent, optimally damped mechanical system. In this chapter, a prototype electromechanical TMD is developed and tested to validate the findings of the theoretical study. The effect of the piezoelectric energy harvesting on the dynamics of the system (via the alteration of the R-L-C parameters) is investigated. It shall be noted that the larger size variable R-L-C boxes, used in this study, facilitate swift tuning and adjusting of R-L-C values during the experiment. In practice, a compact dual function EH/TMD can be realized by following the theroy of this chapter. The chapter begins with a description of the experimental set-up used in this study, followed by a presentation of the test results along with the simulation results.