**Author details**

20 Will-be-set-by-IN-TECH

Therefore, for the overall optimal location a trade-off is necessary, and the piezoceramics is placed with *r* = 97.5mm and *α* = 22.5◦. In this case the coupling with both the bending and

Finally, measurements are conducted with the BLISC test rig. The system is excited harmonically by additional piezoceramics placed at the back side at identical positions as the shunted ones at the front side. One single passive *LR* network is connected to all piezoceramics simultaneously, and the electrical eigenfrequency and the damping ratio are set to the optimal values according to the previous sections. Figure 16 shows the measurement as well as the simulation results for isolated electrodes and optimal *LR*-shunting. Generally, the

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Measurement w/o LR Measurement with LR Simulation w/o LR Simulation with LR

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Excitation Frequency [Hz]

**Figure 16.** Simulated and measured frequency response of the BLISC model for isolated electrodes and

simulation results are in very good agreement with the measured ones. The damping effect of

This chapter deals with shunted piezoceramics for vibration damping. A small overview of typical shuntings is presented. Further on, a general model of a one degree of freedom mechanical oscillator with embedded piezoceramics and external electrical circuit is derived. Based on this system, the optimal tuning of a resonant *LR*-shunt is performed for a damped mechanical system. The influence of the mechanical damping upon the optimal parameters and the resulting damping performance is studied. Further on, a novel combination of a 'SSDI' switching circuit and a negative capacitance is discussed. It is shown that this network

Excitation Frequency [Hz]

torsion mode is about *K* = 2%.

<sup>10</sup>−7

−270

the shunted piezoceramics is clearly visible.

−180

Phase [°]

*LR*-shunting.

**7. Conclusions**

−90

0

<sup>10</sup>−6

Amplitude [m/V]

<sup>10</sup>−5

<sup>10</sup>−4

*6.2.2 Measurements*

Marcus Neubauer, Sebastian M. Schwarzendahl and Xu Han *Institute of Dynamics and Vibration Research, Leibniz University Hannover, Germany*
