Micro enano energy harvesting

Transcription

1 Micro enano energy harvesting Helios Vocca NiPS Lab, Physics Dept., University of Perugia, IT & Wisepower srl

2 Who are we? In Arcadia, California The NiPS experience covers: Noise in Physical systems > (Nips) Thermal noise in equilibrium and out of equilibrium High sensitivity measurements Low dissipation materials and coatings (high Q) Non Linear Dynamics Stochastic Dynamics (stochastic resonance) => Energy harvesting Helios Vocca Workshop FE SEM Apr. 20th,

3 Our energy harvesting present projects Nanopower EC FET Proactive, 3 M ZEROPOWER EC FET Proactive, 600 k ENERGY HARVESTING MOBILE ONRG (US NAVY), 120 k ENERGY HARVESTING II PRIN2009 (MIUR), 65 k Landauer EC FET Proactive ~ 3 M in negoziation Nips, UniWurz, VTT, ICN, UniGeneva, UniCam Nips, UniGlasgow, UniCork, UAB Nips, ONR San Diego UniCT, Nips, UniBS Nips e Ghost (UniPG), UniWurz, UniDelft Helios Vocca Workshop FE SEM Apr. 20th,

4 Beyond the batteries Computing devices are becoming ubiquitous and pervasive! Wireless Sensor Networks are becoming more and more diffuse. Laptop Smartphone Wireless sensor nodes Wearable sensors Power requirements must be scaled down, for size of <1cm 3 the power consumption goal is below 100 μw Problem: batteries must be recharged/replaced and small batteries do not exist! Helios Vocca Workshop FE SEM Apr. 20th,

5 Energy harvesting as alternative for micropowering NO NEED TO REPLACE BATTERIES! Generator (EH) Temporary Storage system Electronic device Power sources Piezoelectric Electrodynamics Photovoltaic Thermoelectric Ultra capacitors Rechargeable Batteries Low power devices Wireless Sensors MEMS actuators Consumer electronics Photons: Light, Infrared, Radio Frequencies Energy harvesting for self organising, ii Kinetic: : vibrations, human motion, wind, hydro pervasive, nearly invisible and self Thermal: temperature gradients powered Wireless Sensor Networks can Biochemical: glucose, metabolic reactions be the solution. Helios Vocca Workshop FE SEM Apr. 20th,

6 WSNs have vast applications Environmental Monitoring Habitat Monitoring (light, temperature, humidity) Integrated Biology Structural Monitoring Interactive and Control RFID, Real Time Locator, TAGS Building, Automation Transport Tracking, Cars sensors Surveillance Pursuer Evader Intrusion Detection Interactive museum exhibits Medical remote sensing Emergency medical response Monitoring, pacemaker, defibrillators Military applications and Aerospace The main challenge for WSNs is to be SELF POWERING!! Helios Vocca Workshop FE SEM Apr. 20th,

7 Vibration energy harvesting Electromagnetic Wireless Device/Sensor Circuit Regulator & Storage Electrostatic/Capacitive Vibration Energy Harvester Piezoelectric Ambient vibrations Human motion Wind, Hydro Magnetostrictive Helios Vocca Workshop FE SEM Apr. 20th,

8 State of the art macro to millimetric i generators Electrodynamic Perpetuum PMG17 (England) Up to 1g rms (15Hz) Piezoelectric Mide Volture (USA) 1grms (50Hz) Electrostatic/Capacitive ESIEE Paris A. Mahmood Parracha npower PEG Holst IMEC (Germany) Micro PZ generator 500Hz 1g Imperial College, Mitcheson 2005 (UK) Electrostatic generator 20Hz 1g Micro electromagnetic generator S. Beeby 2007, (UK) Microlab at UC Berkeley (Mitcheson) Helios Vocca Workshop FE SEM Apr. 20th,

9 Linear systems are widely used 1) They can be easily realized with cantilevers and pendula 1) There exist a simple math theory to solve the equations Ambient energy Electric power Linear oscillator 2) They have a resonant behaviour (resonance frequency) 9 Helios Vocca Workshop FE SEM Apr. 20th, 2012

10 Limits of linear systems: The frequency spectrum of available vibrations instead of being sharply peaked at some frequency is usually very broad. The frequency spectrum of available vibrations is particularly rich in energy in the low frequency part and it is very difficult, if not impossible, to build small low frequency resonant systems W l t Helios Vocca Workshop FE SEM Apr. 20th,

11 The vibration harvester 2.0 (nonlinear) Better performances of nonlinear systems have been demonstrated Capable of harvesting energy on a broad band No need for frequency tuning Capable of harvesting energy at low frequency increasing D Result: output power is maximum for an optimal nonlinear regime Helios Vocca Workshop FE SEM Apr. 20th, 2012 PATENTS: PCT/IT2008/ WO/2008/ US2010/ A1 PCT/IT2011/ Bistable Piezoelectric i Generator Nonlinear electric generator 11

12 Micro to nano vibration harvesters With this approach with our partners we are developing energetically autonomous mems and nems: In collaboration with CEA Leti we are investigating g linear and nonlinear dynamics of μcantilevers. Helios Vocca Workshop FE SEM Apr. 20th,

13 Membranes from VTT (Helsinki) Helios Vocca Workshop FE SEM Apr. 20th,

14 Nonlinear membranes and beams from VTT Helios Vocca Workshop FE SEM Apr. 20th,

15 Nonlinear membranes from VTT Helios Vocca Workshop FE SEM Apr. 20th,

16 Conclusions Vibrations represents one of the most promising renewable and reliable solutions for mobile electronics powering. Most of vibrational energy sources are inconsistent and have relative low frequency. Scaling from millimeter down to micrometer size is important as well as further improvement of conversion efficiency. Non linear mechanical oscillators outperform linear ones in noisy environments. Non linear systems are more difficult to treat but more interesting, and especially they work in general environments! Let s start to develop new micro & nano applications (i.e. WSN, smart cements, etc) Helios Vocca Workshop FE SEM Apr. 20th,