Optimal Control of Traffic Lights in Urban Area

The rising number of people working and living in big cities around the world, many of which own a personal car, lead to a well-known social problem, namely, traffic congestions. Congestions occur when a large number of road traffic participants aim to use the very same infrastructure, while the latter has limited capacity. This situation entails a number of negative consequences, such as slow motion, economic losses, environmental pollution, safety problems and road accidents. The implementation of appropriate transport infrastructure management can make traffic more efficient, safer and greener.Traffic management in an urban environment is mainly realized through traffic light management. It is an integral part of the intelligent transport system (ITS), which is essential for facilitating traffic congestion. Poor traffic management and inefficient settings at signalized intersections cause many problems such as excessive delays for vehicles, increased fuel consumption and CO2 emissions generated by transport means. The efficiency of signalized intersections can be significantly improved by optimizing phase duration and synchronizing traffic lights using intelligent traffic management methods. For this reason, the paper demonstrates the use of the built-in Excel GRG Nonlinear Multi-start application for improving the level of service (LOS) in intersection by optimizing the phase length and cycle of two isolated traffic lights. The average weighted controlled vehicle delay at the intersection is the indicator for assessing the effectiveness of the objective function. The results of the study show that the calculated values for delays for passing through intersections have decreased.