ROADSIDE project
Start month: January 2026 | End month: June 2027
ROADSIDE (dRone mOnitoring of differentiAl speeD limitS In congesteD nEtworks) aims to advance the design, evaluation, and potential implementation of lane-specific variable speed limit (VSL) strategies in modern motorway environments. As traffic systems become increasingly complex due to congestion, mixed vehicle fleets, and the gradual integration of connected and automated vehicles (CAVs), there is a growing need for more targeted and adaptive traffic management solutions. ROADSIDE addresses this challenge by combining innovative data collection methods with advanced traffic analysis and modeling approaches.
At the core of the project is the use of drone-based monitoring to capture high-resolution, lane-level vehicle trajectory data under real traffic conditions. This approach overcomes the limitations of traditional infrastructure-based sensing systems, enabling a detailed understanding of driver behavior, lane interactions, and congestion dynamics. The collected data are used to generate precise vehicle trajectory datasets, which form the basis for both empirical analysis and the calibration of microscopic traffic simulation models.
Building on this data, ROADSIDE investigates the performance and feasibility of lane-specific VSL strategies, where different speed limits can be applied to individual lanes rather than uniformly across the roadway. The project evaluates how such strategies impact traffic flow efficiency, safety, and stability, particularly in congested conditions and mixed traffic environments. Special attention is given to the interaction between conventional vehicles and emerging CAV technologies, as well as to the role of compliance and real-world driving behavior.
A key objective of ROADSIDE is to move beyond purely simulation-based assessments by grounding the analysis in real-world observations collected on Swiss motorways. This enables the development of context-specific insights that reflect local infrastructure characteristics, traffic patterns, and regulatory conditions. The project also considers practical implementation aspects, including technological requirements, operational constraints, and potential barriers from a legal and administrative perspective.
Through ROADSIDE we aim to provide traffic authorities and stakeholders with robust, evidence-based recommendations to support the future deployment of advanced VSL systems. By bridging the gap between research and real-world application, the project contributes to safer, more efficient, and more sustainable motorway traffic management, while supporting the broader transition toward intelligent and adaptive transport systems.
The project is funded by the working group MB4 - Mobility 4.0 of the Swiss Federal Road Office.
