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Project Type
UTRC Research Initiative
Project Dates
01/01/2014 - 12/31/2014
Principal Investigators
Project Status

In 2012, there were 139 incidents in which people got hit by subway trains in New York City, compared with 146 in 2011. Most of the victims slipped or fell or went on to the tracks to fetch personal belongs. A promising approach to reduce future occurrence of such tragedies is distributed sensor nodes that detect obstacles and monitor train motion [1]. In such applications, an important limitation is the near impossible task of maintaining numerous sensors and microsystems. Accordingly, the development of alternate low-cost and reliable distribute power sources would fill an acute need to replace traditional batteries or electricity supply. To this need, energy harvesting of ambient vibrations and pneumatic vortices induced by running subway trains is proposed to enable self-sufficient wireless sensor nodes and/or many other surveillance devices. A primary issue limiting energy harvesting advances is its poor efficiency, as linear generators still use frequency matching to achieve optimal harvesting performance [2]. However, in practice, the power output can be drastically reduced due to many limiting factors that may result in mismatch between the excitation and the resonance frequencies. Recently, piezoelectric energy harvesting using coupled magnets has been proposed to enhance bandwidth and therefore the harvesting efficiency [3,4]. However, to date, coupling the electromagnetic and piezoelectric transduction mechanisms in one device has not yet been investigated nor has pneumatic vortices yet been used as an ambient power source. This underscores the promising idea of my proposal, which is to develop broadband hybrid electromagnetic and piezoelectric harvesters that rely on ambient vibrations and pneumatic vortices induced by running subway trains. The main objectives of this proposed research are: 1) How to convert ambient vibrations and pneumatic wave vortices to electric power? 2) What is the harvested output power? Is it sufficient to power a sensor network? 3) To use the results from this UTRC investment to develop proposals to interested industries and agencies to address this important societal need of public health and safety.