journal article·2021-03-13Open access

Variable Speed Limit and Ramp Metering for Mixed Traffic Flows: A Review and Open Questions

Filip Vrbanić, Edouard Ivanjko, Krešimir Kušić, Dino Čakija

Applied Sciences· Volume 11· Issue 6

Abstract

The trend of increasing traffic demand is causing congestion on existing urban roads, including urban motorways, resulting in a decrease in Level of Service (LoS) and safety, and an increase in fuel consumption. Lack of space and non-compliance with cities’ sustainable urban plans prevent the expansion of new transport infrastructure in some urban areas. To alleviate the aforementioned problems, appropriate solutions come from the domain of Intelligent Transportation Systems by implementing traffic control services. Those services include Variable Speed Limit (VSL) and Ramp Metering (RM) for urban motorways. VSL reduces the speed of incoming vehicles to a bottleneck area, and RM limits the inflow through on-ramps. In addition, with the increasing development of Autonomous Vehicles (AVs) and Connected AVs (CAVs), new opportunities for traffic control are emerging. VSL and RM can reduce traffic congestion on urban motorways, especially so in the case of mixed traffic flows where AVs and CAVs can fully comply with the control system output. Currently, there is no existing overview of control algorithms and applications for VSL and RM in mixed traffic flows. Therefore, we present a comprehensive survey of VSL and RM control algorithms including the most recent reinforcement learning-based approaches. Best practices for mixed traffic flow control are summarized and new viewpoints and future research directions are presented, including an overview of the currently open research questions.
Source: crossref · Quality: baseline

Research context

OpenAlex topics: Traffic control and management · Transportation Planning and Optimization · Traffic Prediction and Management Techniques

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

Faculty of Transport and Traffic Sciences, University of Zagreb, Vukelićeva Street 4, HR-10000 Zagreb, Croatia

Funding

European Regional Development Fund (DATACROSS)

References (100+)

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