{"id":1589,"date":"2010-07-12T10:55:33","date_gmt":"2010-07-12T14:55:33","guid":{"rendered":"https:\/\/wpmu2.mit.local\/?p=1589"},"modified":"2010-07-22T13:56:29","modified_gmt":"2010-07-22T17:56:29","slug":"ultra-wide-bandwidth-micro-energy-harvester","status":"publish","type":"post","link":"https:\/\/wpmu2.mit.local\/ultra-wide-bandwidth-micro-energy-harvester\/","title":{"rendered":"Ultra-wide-bandwidth Micro Energy-harvester"},"content":{"rendered":"

A novel ultra-wide-band resonating thin-film PZT MEMS energy-harvester has been developed. It harvests energy from parasitic ambient vibration at a wide range of amplitude and frequency via the piezoelectric effect. Up to this point, the designs of most piezoelectric energy devices have been based on high-Q linear cantilever beams that use the bending strain to generate electrical charge via the piezoelectric effect [1<\/a>]<\/sup> [2<\/a>]<\/sup>. They suffer from very small bandwidth and low power density, which prohibit practical use. Contrary to the traditional designs, our new design utilizes the tensile stretching strain in doubly-anchored beams [3<\/a>]<\/sup>. The resultant stiffness nonlinearity due to the stretching provides a passive feedback and consequently an ultra-wideband resonance [4<\/a>]<\/sup>. This wide bandwidth of resonance enables a robust power generation amid the uncertainty of the input vibration spectrum. This work includes the design, microfabrication, and testing of a MEMS-scale prototype that aims to harvest up to 0.1mW electrical power in a wide range of excitation frequencies. Mechanical testing has shown 10-fold improvements in the displacement bandwidth. Our simulation predicts 100-fold improvement in the electrical power bandwidth compared to the conventional linear designs. Currently, a new generation of the device is under fabrication and testing at MTL and MNSL facilities.<\/p>\n\n\t\t