Adaptive Traffic Control System

The adaptive traffic light control systems PTV Epics and PTV Balance are innovative and cost-efficient software solutions that continually optimize the traffic light control at signalized intersections and across entire networks. They ensure that green phases correspond to real time traffic conditions rather than to traffic patterns. The goal of these state-of-the-art adaptive traffic control systems is to manage the available infrastructure capacity efficiently, while contributing to road safety, improving traffic flow and reducing congestion in inner cities. Thereby, they contribute to better quality of life, improve air quality and increase the reliability and punctuality of public transport services.

PTV Epics analyses traffic conditions locally and determines the best control option for single nodes based on the situation at hand on the roads. The adaptive traffic signal control system decides in seconds whether a phase needs to be omitted, shortened or lengthened. To coordinate signals over multiple signalized intersections and reduce congestion across your entire network, PTV Balance transmits the ideal traffic signal timing for a particular phase to the local adaptive signal control system, allowing vehicles to travel down a corridor on a green wave without stop-and-go. Traffic light control with PTV Epics and PTV Balance helps cities to move vehicles on the roads more efficiently, improves air quality and ensures that public transport lines operate according to schedule.

Adaptive traffic light control for single nodes is an efficient and effective way to reduce stop-and-go traffic and to keep inner-city traffic moving without expanding road infrastructure. PTV Epics was developed specifically for single signalized intersections and runs directly inside the control unit. The model-based process observes local real-time conditions and calculates numerous control options every second. The adaptive traffic signal control for nodes then uses its internal model to evaluate the different options before applying the most suitable one. In this process, it takes all modes of transport into account - from individual motorized transport and pedestrians to prioritizing public transport.

The underlying parameters, e.g. minimum and maximum phase duration, green phases for the different signal groups, the permitted phase sequences and the weighted requirements for private and public transport and pedestrians, can be defined individually to achieve a specific goal. For example, to make public transportation more attractive and to reduce emissions, a growing number of cities prioritize public transport over personal vehicles in traffic.

PTV Balance allows you to orchestrate traffic lights across multiple nodes to cover entire networks and activate green waves. This way, you free your city from spillbacks and long queues and reduce emissions. Unlike systems with a fixed signal control, adaptive traffic signal control reacts to what's happening on the road and efficiently utilizes the capacity of all intersections across entire networks.

At the heart of the software is a two-layer real time transport model. In the macroscopic stage, PTV Balance uses detector data to derive the traffic density on individual routes and side roads. Based on the results of the macroscopic model, PTV Balance calculates different strategic framework signal plans. An integrated mesoscopic model evaluates the traffic signal control options over multiple nodes within seconds – taking into account factors like their effects on stops, waiting times and blocking backs. This evaluation is based on a custom performance index, which represents the weighted sum of all relevant factors.