A practical application of energy harvesting based on piezoelectric technology for charging portable electronic devices

Developing methods for energy harvesting from the human body is a research field that can offer remarkable advances in medical and portable electronic devices, such as glucose monitoring (CGM) systems and cardiac pacemakers. Proper functionality of these devices relies heavily on the continuous supply of a sufficient amount of electricity and piezoelectricity must be included in the search of methods that can improve the aforementioned portable medical devices. This paper focuses on energy harvesting systems which the use of smart materials, such as piezoelectric transducers, in order to produce and save energy, exploiting the body as an energy source. This work also presents the implementation of two applications which are based on piezoelectricity in order to produce and save energy in a tiny battery. The first application involves the construction of a piezoelectric glove which produces energy from the force exerted by the fingers, using as base materials piezoelectric transducers. The practical implementation of this application and the measurements made on an integrated circuit, proved that 0.3236W of energy can be produced, by exerting force by the fingers on a flat surface. Moreover, a keystroke scenario and a scenario of using a tablet were investigated in which, 0.0187W were produced in 25 minutes and 0.0267W in 9 minutes, respectively. The second application involves the implementation of a piezoelectric wireless computer mouse which produces electricity, utilising the force exerted by the fingers clicking on mouse buttons. The assessment of this application proved that the battery voltage increased from 0.61V to 0.7V with 375 mouse clicks. (C) 2017 Elsevier Ltd. All rights reserved.