Nonlinear vibration energy generators with mechanical stops for low-frequency broadband applications

A variety of energy-autonomous sensor systems are excited by a spectrum of excitation frequencies. Especially in the low-frequency range, an optimal system design is important because the available energy for conversion is relatively low. Because the maximum deflection for multimodal excitations is dependent on the stochastic phase, mechanical stops must be implemented to prevent an overloading of the springs. Due to the nonlinear effect of the mechanical stops, only an expected value of the mean output power can be specified. The standard deviation increases with the occurrence of contacts between the seismic mass and the stops. This paper presents a comparison between a linear approach and nonlinear simulations.