The target of the research activity presented in this paper is to design, to realize and to test an autonomous sensor node able to measure the accelerations in correspondence of the axle box of a freight train. The final goal of the sensor is to identify the derailment conditions by observing the variations in the spectra of the box accelerations, around the frequencies associated to the wheel revolution and its multiples.

The sensor node embeds an accelerometer, a microprocessor, a transmission system, a piezoelectric bimorph energy harvester and an integrated circuit for managing the power distribution to each component of the node.

In particular, a mechanical filter to be applied to the node was specifically designed to increment the energy recovered by the harvester and to filter out the high frequency components of the axle-box acceleration, allowing the use of a more sensitive accelerometer. The harvesting system was setup by means of laboratory tests carried out with an electromechanical shaker and the sensor node was finally tested through field tests on freight trains.

Date Published: 20 April 2016
PDF: 10 pages
Proc. SPIE 9803, Sensors and Smart Structures Technologies for Civil, Mechanical, and Aerospace Systems 2016, 98034W (20 April 2016); doi: 10.1117/12.2220770

Published in SPIE Proceedings Vol. 9803:
Sensors and Smart Structures Technologies for Civil, Mechanical, and Aerospace Systems 2016
Jerome P. Lynch, Editor(s)