DITS S.r.l. has implemented the BANDITS 1.0 software tool (BANdella – Dinamica Infrastruttura TramWave Sistema d’alimentazione) intended for the dynamic analysis of the continuous steel band that allows the activation of the ground contact line when the on-board magnet of the TramWave vehicle passes. The activation of the contact line means that it is tensioned in a short area underneath the vehicle, thus allowing the electrical power supply for its activation. The continuity of the band is obtained by connecting a series of modules 3 – 5 meters long. Each module consists of a box containing a portion of the band joined at the two ends with the similar portions of the adjacent modules. The magnet on the tram attracts the band upwards, lifting a portion of about 3 meters long from its lower supports. This allows the tensioning via the upper electrical contacts. A portion of the strip thus comes into contact with the upper internal surface of the box (the “upper contact”). Obviously, the two adjacent portions remain suspended (“floating” portions), with no contact between the strip and the box. As the vehicle travels along the track, the raised portion of the strip moves with it, creating a traveling wave. The movement of the tram also creates vibrations of the “floating” portions of the strip and causes variations in the length of the upper contact and the floating portions.
The study explores the dynamic behavior described above in the range of travel speeds 0-70 km/h, in order to identify potential dynamic criticalities.
The study was started by repeating and verifying the linear static and dynamic analytical calculations already available. A non-linear finite element model (FEM) of the strip was then built using the GNU software called Salome-Meca, whose development is directed by Electricité de France. Its first results were verified by comparison with those of analytical calculations (in terms of static deflections and natural frequencies) and with some preliminary experimental results (in terms of natural frequencies).
The BANDITS 1.0 tool was then created in a Python environment, based on the FEM model, used to study the dynamic behavior of the band and to produce highly immediate graphic representations (video) of the same.

Job name: Development of an application for the dynamic simulation of the behavior of the ‘band’ of the Tramwave system as the vehicle speed varies. Construction of a refined dynamic model, graphical interface and output data.
Year: 2015
Client: Ansaldo STS S.p.A.
Type of work: Consulting and software
Website: https://www.hitachi.com/