# Snap-Through Buckling Mechanism for Frequency-up Conversion in Piezoelectric Energy Harvesting
## 5 Discussion and Conclusions  
On the basis of the results obtained from the experimental tests and the numerical simulations, the effectiveness of FuC due to STB of the designed device is demonstrated. As a matter of fact, when the bistable mechanism is subject to a displacement and let free to impulsively snap from the reversed to the initial state, the measured output voltage of the converter contains a wide range of high frequency components. The employment of a tip mass, while reducing the resonance frequency of the bimorph beam, implies a significant increase in terms of voltage output, due to the increased deformation of the beam, leading to higher strains in the piezoelectric layers. The results obtained from the experimental tests are compared with those coming from a FE model accounting for geometrical nonlinearities and for the electromechanical coupling, showing a good agreement. Figure 17: Fourier transform of the open-circuit output voltage obtained during the STB tests with sinusoidal excitation at frequencies of 20, 25 and 30 Hz with peak amplitudes of 1, 1.5, 2, 2.5, and 3 g. The vertical dashed lines denote the excitation frequency. Figure 18: Mean power as a function of the peak amplitude of the sinusoidal excitation at frequencies of 20, 25, and 30 Hz for \(R_{\mathrm{L}}=400\,\mathrm{k}\Omega\). * [PERSON] and [PERSON] (1996) [PERSON]; [PERSON] Analysis of a micro-electric generator for microsystems. _Sensors Actuators A Phys._**1996**, _52_, 8-11. [CrossRef]
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