Design of a MEMS-Based Piezoelectric Vibration Energy Harvesting Device for Automotive Applications

Abstract

The automotive industry requires new sensors to improve automotive performance,comfort and safety. These sensors will need the electrical power for their operation,which could be supplied by future MEMS energy harvesting devices. We present thedesign of a MEMS-based piezoelectric vibration energy harvesting (PVEH) device. Thedesign is formed of two cantilevers of trapezoidal shape (2500  1064  9 μm) that havetwo proof masses in their ends. The cantilevers and proof masses are designed of siliconwith a PZT-5H film, considering the PiezoMUMPs fabrication process of MEMSCAP. ThisPVEH device can generate voltage when its structure is deformed at resonance under avibration acceleration. Finite element method (FEM) models of the PVEH device are developedto predict its electrical and structural behavior at resonance under a vibrationacceleration of 12 m/s2. The proposed device has a resonant frequency of 207.8 Hz, amaximum deflection of 201 μm and a generated voltage of 61.5 mV with an electrical resistiveload of 10 kΩ. A PVEH devices array could be used to supply electrical power tosensors of modern and future automobiles.