A Nonlinear Energy Harvester by Direct Printing Technology

This paper presents an energy harvester based on a bistable clamped-clamped beam to collect energy from wideband vibrational sources at low frequencies. The device exhibits a nonlinear dynamic behaviour which can be described by a double well bistable potential with a switching threshold and two stable equilibrium states. The beam switching is activated by environmental vibrations. The mechanical-to-electrical energy conversion is performed by a screen printed piezoelectric layer electrically connected using InterDigiTed Electrodes (IDT) realized by the inkjet printing of a silver based solution on a flexible PET (PolyEthyleneTerephthalate) substrate through a cheap commercial EPSON (R) inkjet printer. Main advantages of the proposed approach are related to the wide frequency band assuring high device efficiency and low cost technologies adopted to realize both electrodes and the piezoelectric layer. (C) 2012 Elsevier Ltd....Selection and/or peer-review under responsibility of the Symposium Cracoviense Sp. z.o.o.