Abstract
Traffic optimization at an intersection, using real-time traffic information, presents an important focus of research into intelligent transportation systems. Several studies have proposed adaptive traffic lights control, which concentrates on determining green light length and sequence of the phases for each cycle in accordance with the real-time traffic detected. In order to minimize the waiting time at the intersection, the authors propose an intelligent traffic light using the information collected by a wireless sensors network installed in the road. The proposed algorithm is essentially based on two parameters: the waiting time in each lane and the length of its queue. The simulations show that the algorithm applied at a network of intersections improves significantly the average waiting time, queue length, fuel consumption, and CO2 emissions.
TopTraffic Light Regulation
In cities, most traffic lights control systems are of two types: fixed lights control plan and adaptive control. The first type of regulation is older and less expensive, while the second is more complex and efficient. We present in this part the specifications of each of those types of regulation. But first, we will give a number of definitions for the intersection and its operation.
Key Terms in this Chapter
SUMO Simulator (Simulation of Urban Mobility): Is a road traffic simulator that models the behavior of vehicles at the different flows of an intersection or a network of intersections. This simulator allows us to reproduce user behavior by generating the observations that would normally come from the detectors. This makes it possible to replace the ITS information and to evaluate the performance of the traffic control approach as a whole. They are called “Intelligent” because their development is based on functions generally associated with intelligence: sensory capabilities, memory, communication, information processing and adaptive behavior.
Intelligent Transportation Systems (ITS): Have attracted considerable attention in recent years especially with the significant progress made in the field of computer and telecommunication technologies. ITS intervenes in a global context of traffic congestion on the one hand and development of new information technologies on the other, particularly in the areas of simulation, real-time traffic control. telecommunication networks.
Detector: Is a technology that collects and transmits environmental information to a processing node.
Green Light Time: Is a time interval during which several movements are allowed in the intersection. A cycle is divided into several phases, each of which has a duration of green light that it is essential to properly regulate. Indeed, a phase too short may not allow enough time for a queue to discharge. Conversely, a phase that is too long increases the waiting time for drivers present on the other phases, without being useful.
Wireless Sensor Network (WSN): A wireless sensor network is a set of sensor nodes communicating wirelessly. These sensor nodes are able to self-organize into distributed subnets to collect information from the physical world on which they are deployed.
Traffic Lights Plan: Corresponds to the description of a given cycle, and defines the different phases to be unfolded as well as their duration. Generally, a traffic lights plan is designed for a specific time slot, depending on the average level of traffic to be absorbed (eg, a shorter traffic lights plan for the night, a longer one in rush hour).
Junction or Road Intersection: Is located at the intersection of several streets defining entrance and exit lanes. It can take many forms, both in infrastructure and in crossing rules. The directions of vehicles are either go straight, turn left, or flow to turn right. Vehicles are always allowed to turn right without restricting traffic.