an investigation into resonant frequency of triangular v-shaped cantilever piezoelectric vibration energy harvester

Power supply is a bottle-neck problem of wireless micro-sensors, especially where the replacement of batteries is impossible or inconvenient. now piezoelectric material is being used to harvest vibration energy for self-powered sensors. however, the geometry of a piezoelectric cantilever beam will greatly affect its vibration energy harvesting ability. this paper deduces a remarkably precise analytical formula for calculating the fundamental resonant frequency of v-shaped cantilevers using rayleigh-ritz method. this analytical formula, which is very convenient for mechanical energy harvester design based on piezoelectric effect, is then validated by abaqus simulation. this formula raises a new perspective that, among all the v-shaped cantilevers and in comparison with rectangular one, the simplest tapered cantilever can lead to maximum resonant frequency and highest sensitivity.