I. Introduction
To scavenge mechanical vibration, we have to create an artificial mechanical reference point with an inertial mass and then translate the relative displacement between the vibration source and this inertial mass in electrical energy by a mechanical to electrical converter. We can theoretically show that the main limitation in vibration energy harvesting is the available input energy given by the inertial mass and the input vibration. The input vibration is given by the environment and can not be change and, in order to minimize the system size, we have to optimize the use of the inertial mass that can represent the main part in mass and volume of the system. For assuming that, we did some acceleration measurements in different environments (transport, industrial machine…) and we chose the resonant frequency (50 Hz) and the electrical damping that maximize the mechanical energy extraction for a normalized inertial mass. We demonstrated in a precedent paper [1] that for obtain a wide band of frequency system able to satisfy these different environments, a high equivalent electrical damping (≥0.1) is required and this high damping can only be obtain with an electrostatic transduction in case of low input frequencies (<120Hz) and for a small system size (<3 cm3).