In November 2014, Nabla Quadro and Roma Servizi per la Mobilità srl (public transport agency) started a pilot experiment to evaluate an innovative wireless system for train detection on a mixed-use road.
The main purpose is to detect when a tram is in transit, in order to apply preferential mobility politics.
The installation is composed of 4 aligned sensors between two rails, placed at a fixed distance (longer than a car). Trains are detected through a classification by length of the vehicles in transit. In fact, when a train goes by on the rails it obscures progressively all the 4 sensors without interruptions, i.e. the first sensor is still occupied when the last one is. This means that the vehicle in transit is longer than the distance occurring between the first sensor and the last one, so it is a train and not a car.
Roma Servizi per la Mobilità srl had already tested other kind of sensors (mostly magnetic) and cameras for the same purpose, but they didn’t reach the goal. The reason was that magnetic sensors decrease their accuracy in congested traffic conditions, while Nabla Quadro sensors keep their precision due to their optical detection mode. Moreover, being a wireless system, times and costs for installation and maintenance are much less than other intrusive sensors, as well as cameras.
The pilot experiment has given stunning results and it has been the starting point of next projects for traffic management in the City of Rome, as traffic light control in via Nomentana and via Casilina.