A Laser-micromachined Vibrational to Electrical Power Transducer for Wireless Sensing Systems

Summary

This paper presents the development of a vibration-induced power generator with total volume of ∼cm³ which uses laser-micromachined springs to convert mechanical energy into useful electrical power by Faraday’s Law of Induction. The goal of this project is to create a minimally sized electric power generator capable of producing enough voltage to drive low-power ICs and/or micro sensors for applications where ambient mechanical vibrations are present. Thus far, we have fabricated generators with total volume of 1cm³ that are capable of producing up to 4.4V peak-to-peak, which have a maximum rms power of ∼680µW with loading resistance of 1500Ω. The mechanical vibration required to generate this electrical energy has frequencies ranging from 60 to 110Hz with ∼200µm amplitude. We have demonstrated that this generator can drive an IR transmitter to send 140ms pulse trains every minute, or a 914.8MHz FM wireless temperature sensing system.