• Energy Research

Magneto-rheological fluids, or MRF, have been known for a long time in the technological and scientific community [...]

The concept of power harvesting works towards the development of self-powered devices not requiring replaceable power supplies. The increase in power used by the electronics has led to a reduction in battery life and has limited the functionality of the devices. In an effort to extend the life and to reduce the volume of the electronics, researchers have begun investigating methods to obtain energy from the ambient energy surrounding the device. In this work the authors focused on the characterization of a piezoelectric vibration harvesting device to be applied in a train derailment detector system, in which the harvesting device supplies the wireless transmission unit sending warning messages to the trains driver. In what follows the attempt to harvest energy by means of a specific architecture to be placed, according to the project specifications, on the train gear, is presented.

By introducing the progresses on Morphing currently achieved within the European Project “AIRGREEN2”, in Clean-Sky 2 GRA platform, this work presents a review of the research step forwards accomplished in the last decade by three Italian Partners largely active in the field: the Italian Aerospace Research Centre, the University of Naples “Federico II” and the Politecnico of Milano. A chronologic overview is at first presented, revisiting the research programs and the achieved results; an organic development path has been then built, starting from low TRL achievements up to arrive at the most complete technical accomplishments, characterized by a high level of integration and targeting specific aerospace applications.

Today, as railways increase their capacity and speeds, it is more important than ever to be completely aware of the state of vehicles fleet‟s condition to ensure the highest quality and safety standards, as well as being able to maintain the costs as low as possible. Operation of a modern, dynamic and efficient railway demands a real time, accurate and reliable evaluation of the infrastructure assets, including signal networks and diagnostic systems able to acquire functional parameters. In the conventional system, measurement data are reliably collected using coaxial wires for communication between sensors and the repository. As sensors grow in size, the cost of the monitoring system can grow. Recently, auto-powered wireless sensor has been considered as an alternative tool for economical and accurate realization of structural health monitoring system, being provided by the following essential features: on-board micro-processor, sensing capability, wireless communication, auto-powered battery, and low cost. In this work, an original harvester device is designed to supply wireless sensor system battery using train bogie energy. Piezoelectric materials have in here considered due to their established ability to directly convert applied strain energy into usable electric energy and their relatively simple modelling into an integrated system. The mechanical and electrical properties of the system are studied according to the project specifications. The numerical formulation is implemented with in-house code using commercial software tool and then experimentally validated through a proof of concept setup using an excitation signal by a real application scenario.