Development of a Wireless Traffic Light Controller System, with Real-Time Traffic Monitoring and Green Wave Coordination applied to Smart Cities

摘要

The accelerated urbanization process can cause several traffic problems, such as congestion, environmental, and noise pollution [1]–[3]. The system hardware developed consists of an actuator circuit, for the switching of AC/DC lamps and a sensor circuit, to check if the lamps are burnt out [4]. The microcontroller's firmware performs all the control logic, timing and traffic light safety for each type of crossing [5], [6]. For all traffic lights at all intersections to operate as intended, a wireless communication network with a specific communication protocol was used to mediate the information exchange between the traffic lights at intersections and its control center [7]. Safety routines [8]–[10] have been designed so that, in the event of technical problems (burnt-out lamp, electrical or communication failure) with one or more traffic lights at a given intersection, all traffic lights immediately go into alert mode and notify the situation to the traffic management center. The wireless traffic light controller system (according to Fig. 1) allows the green wave [11], [12] implementation for successive intersections. The system validation was based on the comparison of the theoretical and practical time diagrams, so that in all situations in which the system was exposed, it acted in the way it was designed.