MPC-Based Emergency Vehicle-Centered Multi-Intersection Traffic Control

Abstract

This article proposes a traffic control scheme to alleviate traffic congestion in a network of interconnected signaled lanes/roads. The proposed scheme is emergency vehicle-centered, meaning that it provides an efficient and timely routing for emergency vehicles. In the proposed scheme, model predictive control is utilized to control inlet traffic flows by means of network gates, as well as the configuration of traffic lights across the network. Two schemes are considered in this article: 1) centralized and 2) decentralized. In the centralized scheme, a central unit controls the entire network. This scheme provides the optimal solution even though it might not fulfill real-time computation requirements for large networks. In the decentralized scheme, each intersection has its own control unit, which sends local information to an aggregator. The main responsibility of this aggregator is to receive local information from all control units across the network and the emergency vehicle, augment the received information, and share it with the control units. Since the decision-making in a decentralized scheme is local and the aggregator should fulfill the abovementioned tasks during a traffic cycle, which takes a long period of time, the decentralized scheme is suitable for large networks even though it may provide a suboptimal solution. Extensive simulation studies are carried out to validate the proposed schemes and assess their performance. Notably, the obtained results reveal that traveling times of emergency vehicles can be reduced up to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\sim 50$ </tex-math></inline-formula> % by using the centralized scheme and up to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\sim 30$ </tex-math></inline-formula> % by using the decentralized scheme without causing congestion in other lanes.