Over 50% of the inductive loops installed in the city of Genova to manage traffic lights are out of order. In fact, it is common that broken loops are not replaced due to economic issues because of the high maintenance costs. This is a quite common situation in many cities, since inductive loops are extremely breakable due to asphalt deterioration and heavy traffic and their replacement is very expensive.
Given the background, a test project have been carried out to validate Sky Light technology comparing its performance with inductive loop detectors.
In May 2012, 6 Sky Light Sensors have been installed at a crossroads located in via Milano / via Cantore in Genova. In the same place there were two inductive loops for vehicle detection.
This test was conducted in cooperation with Selex (merged into Finmeccanica S.p.A., today Leonardo).
In order to interface the wireless system with PMFU central unit produced by Selex, Nabla Quadro developed a specific interface card, to “translate” digital information provided by the Sky Light System into analogue contacts.
Wireless sensors have been placed as to replicate two inductive loops in the same position. It has been useful to compare the results obtained from the two kind of traffic detection devices. It is important to stress that this kind of configuration is rather limiting for wireless sensors, since they are able to provide more detailed information. The results prove that data provided from the two kind of detector are strongly congruent. In fact, in the same traffic conditions, they generated the same traffic signal stage.