Scientific Results

Triaxial ball-impact piezoelectric converter for autonomous sensors exploiting energy harvesting from vibrations and human motion

Year: 2015

Authors: Alghisi D., Dalola S., Ferrari M., Ferrari V.

Autors Affiliation: Univ Brescia, Dept Informat Engn, I-25123 Brescia, Italy;‎ INO CNR, I-25123 Brescia, Italy

Abstract: A piezoelectric converter for energy harvesting composed of a rigid ball enclosed among six piezoelectric diaphragms arranged in a cube-shaped structure is presented. When the converter is excited by mechanical vibrations, the ball repeatedly bounces and hits one or more diaphragms, implementing the impact technique in a multi-degree-of-freedom configuration. The structure is isotropic thus the converter is effective irrespective of the vibration orientation. The converter is particularly suitable for energy harvesting from low-frequency random vibrations, such as those provided by human motion. The triaxial ball-impact piezoelectric converter was designed, built and experimentally characterized in the laboratory, and then tied to the ankle of a person and tested during physical activity. While the person is running at 7 km/h, a peak instantaneous power of up to 16 mW is provided by each of the six piezoelectric diaphragms, while the average power is significantly lower. The converter was coupled to a tailored power management circuit which intermittently powers a battery-less wearable temperature sensor module. In about 260 s of walking at 2 km/h, an energy of 1.4 mJ is extracted, stored into a 1-mF capacitor, and used to power the sensor module, which performs a temperature measurement and transmits the data to a receiver through a 433-MHz RF-UART link. (C) 2015 Elsevier B.V. All rights reserved.581


Volume: 233      Pages from: 569  to: 581

KeyWords: Energy harvesting; Piezoelectric converter; Multi-degree-of-freedom converter; Triaxial converter; Ball impact; Frequency-up technique; Autonomous sensor
DOI: 10.1016/j.sna.2015.07.020

Citations: 31
data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2021-10-17
References taken from IsiWeb of Knowledge: (subscribers only)
Connecting to view paper tab on IsiWeb: Click here
Connecting to view citations from IsiWeb: Click here

This site uses cookies. If you decide to continue browsing we consider that you accept their use. For more information about cookies and how to delete them please read our Info Policy on cookies use.
Read more