Abstract
In this work, we are interested in the design of polymerMEMSfor future integration of electroactive materials for mechanical energy harvesting from environmental vibrations. Organic micro-beams are designed by both analytical modeling and finite element analysis to exhibit a low resonant frequency and a high global strain on top surface under vibration. An original method of fabrication combining photolithography and screen-printing is used for the fabrication of these micro-structures. The patterned micro-beams are based on SU8 epoxy photoresist, while the printed seismic mass material is a silver loaded epoxy composite. Trapezoidal shaped micro-beams give the best results with a resonant frequency of similar to 350 Hz and a uniform strain overall the structure, well adapted for a further piezoelectric or electrostrictive transduction. On the other hand, a multimode harvester is realized with a set of micro-beam-mass systems to cover a frequency range larger than 300 Hz, within the standard ambient vibration frequency domain.