Bilbao Port Authority has asked TST to design and develop a wireless remote control system to manage the traffic lights at train level crossings in Bilbao’s harbor.

Problem

Many traffic lights that regulate the traffic along the level crossings of goods trains within the harbor area are mobile traffic lights that have a rechargeable battery with a solar panel, i.e. no wires reach the traffic light. For this reason the system to manage them must be a wireless system.

Due to frequency scans carried out by the police, the system must be robust and reliable against electromagnetic noise and interferences. Furthermore the area to cover with the wireless system is quite extense, since the traffic light most far away from the access point connected to the harbor’s intranet is approx. 900 meters away without line-of-sight.

Solution

TST has developed for Bilbao’s Port Authority a wireless remote control system based on its TSmarT platform and using ZigBee technology. In each traffic light a TST device is installed, which basically consists of a relay controlled by a microcontroller with a ZigBee communication interface. According to the remote commands that are received from the control room, the relays that control the traffic light are switched on and off.

In order to facilitate mobile operations, the system can be also managed by remote controls developed also by TST. Usually train convoys are escorted by the harbor police. When the convoy is about to reach the crossing level, policemen can activate the traffic light or group of traffic lights with the remote control directly from the car.

The network is usually controlled from a web application that can be accessed from any computer within the Port Authority’s intranet. Through this application, authorized users can manually control each traffic light. In case of low battery level of any traffic light, the web application sends an alert per e-mail to maintenance staff.