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Magnets have received broad attention for vibration energy harvesting due to noncontact, nonlinear forces that may be leveraged among harvesting system elements. Yet, opportunities to integrate multi-directional coupling among a nonlinear energy harvesting system subjected to impulsive excitations have not been scrutinized, despite widespread prevalence of such excitations. To characterize these potentials, this research investigates an energy harvesting system with magnetically induced nonlinearities and coupling effects under impulsive excitations. A system model is formulated and validated with experimental efforts to reconstruct static and dynamic properties of the system via simulations. Then, the model is harnessed to scrutinize dynamic response of the system when subjected to impulse conditions. This research reveals the clear impulse strength dependence and influence of asymmetries on total electrical energy capture and energy conversion efficiency that are tailored by magnetic force coupling. Asymmetry is found to promote greater impulse-to-electrical energy conversion when compared to the symmetric counterpart system and a benchmark nonlinear energy harvester. The roles of initial conditions exemplify how stored energy in an asymmetric energy harvesting system may be released during nonlinear impulsive response. These results provide insights about opportunities and challenges to incorporate magnetic coupling effects in nonlinear energy harvesting systems subjected to impulses.
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Obtaining the impulse response from nonlinear spectroscopy measurements by laser normalization
In nonlinear spectroscopies, the detected spectrum is determined by the response of the system to the particular excitation pulses, which can vary as excitation energy and pulse duration are tuned. Here, we analytically show that, under reasonable assumptions, the nested integrals that describe the light-matter interaction of the system can be simplified by application of the Fourier convolution and shift theorems, resulting in an expression for the nonlinear spectrum that is a product of the impulsive system response and the interaction laser spectra. The impulsive response can then be obtained by linearly dividing the laser spectrum from the detected signal. We demonstrate our normalization scheme by recovering the impulsive response from two different material systems, highlighting removal of distinct spectral artifacts.
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- Award ID(s):
- 1906013
- PAR ID:
- 10491642
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Journal of the Optical Society of America B
- Volume:
- 41
- Issue:
- 3
- ISSN:
- 0740-3224; JOBPDE
- Format(s):
- Medium: X Size: Article No. 653
- Size(s):
- Article No. 653
- Sponsoring Org:
- National Science Foundation
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