A piezoelectric vibration harvester based on clamped-guided beams

The paper addresses the design, modeling, fabrication and experimental results of a piezoelectric energy harvester based on clamped-guided beams. The design is featured by shorter mass displacement and higher reliability than cantilever beams. Two separate sets of capacitors allow exploiting both tensile and compressive stress at the same time. The maximum output power reaches about 20 μW at an input acceleration of 1.2 g. A tuning range of 3 Hz is demonstrated by varying the voltage across the capacitors. Nonlinear behavior observed at larger mass displacement is also discussed.