Development of a Mathematical Model for Traffic Light Control

Abstract

the invention of traffic lights has helped to reduce traffic congestion on highways and eased mode of transportation. However, the ever-increasing volume of vehicles has given rise to conflicts, accidents and pollution due to emission from the vehicles. Traffic light switching control could either be pre-timed (Static) or Actuated (Adaptive). In this paper, a comparative study of mathematical models is done to determine the better switching technique for vehicles at an intersection at various levels of saturation and which reduces conflicts and accidents on the highway. For the static time, Webster’s method for the signal design was used to determine the total cycle length of the signal and the approach in the allocation of green-time in a cycle. The adaptive model uses sensors in connection with the control unit to determine the cycle length and also allocate the green and red time depending on the queue length and arrival rate on each of the phases at the intersection. Both models were simulated side by side with simulation of urban mobility (SUMO) programme using python language. Results obtained indicated that the developed adaptive time switching scheme is better in almost all level of saturations as it took less time for the vehicles to exit the intersection and reduced the occurrence of conflicts and accidents at the intersection.