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This paper deals with a recently proposed device for energy harvesting from environmental vibrations, employing a magnetostrictive material. Even if most of the modeling efforts were focused on a linear approach, more complex and nontrivial phenomena are experimentally observed. A sample of such nontrivial behaviors, suggesting the definition of potentially more effective models, is described and discussed in this paper [ABSTRACT FROM AUTHOR]

In this paper a generalization of a stress-dependent magnetostriction phenomenological model is presented. The model makes use of a classical Preisach operator and of a memoryless bivariate function and includes a pure elastic contribution. It is shown that, even if the structure of the model is simple, the operator state is still influenced by the applied stress. This property is important because the model is able to catch real magnetostrictive behavior in the presence of complex time evolutions of both the variables, current and stress. Experimental and numerical results confirm the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

A model for the description of the energy harvesting in magnetostriction devices is discussed. In particular, the effects of hysteresis, normally observed in these materials, are highlighted and compared to the predictions of the linear modeling. The coupling of the model to the circuit equations leads to a differential equation with hysteresis, which could provide an effective macroscopic description of the energy conversion mechanism taking place in these devices. Numerical tests are performed in order to show the effect of a magnetic field bias on the generated electric power. [ABSTRACT FROM AUTHOR]

The paper deals with the mechanical vibrations damping effect induced by a magnetostrictive energy harvesting device properly working. The proposed experimental setup allows us to investigate, through time-domain measurements, the dependence of the mechanical damping from parameters like magnetic bias and external load, affecting the global harvested power. This result would underline the promising possibility to reduce mechanical vibrations and obtain power harvesting at the same time. [ABSTRACT FROM AUTHOR]