Optoelectronic multifunction portals for the monitoring of trains in railway

We report on the development of multifunction portals to monitor trains in railways, to generate alarms in case of an abnormal travelling setup of the train before the entrance in tunnels. The portals monitor (i) 3-D profile of the trains using laser telemeters (two per track), to detect the presence of possible load unbalances, (ii) temperatures of parts of the train using thermal cameras (four per track), detect overheated parts of the train (brakes, locomotive resistors) (iii) 2-D shape of the trains using visible camera arrays (two per track). Auxiliary instruments are sensors for carriage recognition, and to detect carriage borders. A sophisticated Hw/Sw system that controls and synchronizes the above hardware and generates the alarms has been developed. The overall performance of the equipment are (i) up to 700 full 3-D profiles/second at 1024 points per profile (one profile every 5 cm), 512 thermal measurements per second per camera (one thermal profile every 10 cm), and 3600 linear images/second per camera at 512 pixel. The first experimental system is currently installed between Bologna and Prato, and a second system is being installed in the Roma-Neaples railway.