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Urban Freight Lab

Research Keyword: Curb infrastructure

Paper

Evaluating the Impacts of Variable Message Signs on Airport Curbside Performance Using Microsimulation

 
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URL: https://doi.org/10.1177/03611981251387133
Publication: Transportation Research Record: Journal of the Transportation Research Board
Publication Date: 2025
Summary:

Inefficient curb space allocation increases congestion and emissions at airports. Variable message signs (VMS) can alleviate this issue, guiding vehicles from congested to underutilized curbs. However, VMS effectiveness hinges on the right activation and deactivation timing. Using a microsimulation model of the Seattle-Tacoma International Airport, we analyzed the impacts of implementing VMS and determined the best time to turn the sign on and off. We simulated sixteen VMS management scenarios and compared the results against those of a baseline where there was no VMS. We found that strategic and timely management of the VMS is crucial to achieving improvements in congestion and curb performance. Specifically, activating VMS before congestion started on the sending link and deactivating it before congestion began on the receiving link substantially improved curb productivity and accessibility, vehicle delay, and CO2 emissions. On the other hand, if not managed correctly, VMS may lead to little to no improvements, or even negative impacts on traffic conditions and curb performance. For instance, late activation or deactivation can worsen curb accessibility and vehicle delay. Our framework provides valuable insights into how airports could successfully manage VMS technologies.

Authors: Thomas Maxner, Jorge M. Diaz-Gutierrez, Andisheh Ranjbari, Nicola Longo, Nawaf Nazir
Recommended Citation:
Diaz-Gutierrez, J.M. et al. (2025) Evaluating the Impacts of Variable Message Signs on Airport Curbside Performance Using Microsimulation. Transportation Research Record: Journal of the Transportation Research Board. https://doi.org/10.1177/03611981251387133

Open Mobility Foundation: SMART Grant Curb Collaborative

The Open Mobility Foundation’s SMART Curb Collaborative is a group of cities united in tackling challenges in curb management, reducing congestion, enhancing livability, and improving safety and equity on city streets. Each of these public agencies is a recipient of a USDOT Strengthening Mobility and Revolutionizing Transportation (SMART) Grant, which provides funding to build data and technology capacity across the US.

In close coordination with the Open Mobility Foundation (OMF) Collaborative Program Manager, the UFL will support the nine cities of the SMART Grant collaborative as a component of joint services provided through enhanced membership with the OMF. The UFL will lead research initiatives within the Collaborative, contribute academic content and presentations to the group, and work closely with Cityfi and the OMF Collaborative team to support joint deliverables. The UFL will focus on three main thematic areas of inquiry to inform comparative learnings and insights across the Collaborative. The three themes are: curb infrastructure, curb policy, and curb demand.

Objectives

The Urban Freight Lab will:

  • Lead comparative analysis of the Collaborative across various indices (infrastructure, policy, and demand) and connect to questions around the digitization of curbspace
  • Support Cityfi and the OMF Program Manager by contributing expert academic and industry expertise to the Collaborative
  • Support the development of joint deliverables such as case studies.

Task 1. Project Management/Coordination with Collaborative and Support Team

Task 2. Organize and create a comparative rubric of Collaborative projects
The UFL, in collaboration with CityFi and OMF, will help to capture and document an overview of projects, catalog of research objectives and learnings, metrics and data to be collected by cities, and goals of projects. This will help to inform further comparative studies and learnings across the Collaborative.

Task 3. Curb Infrastructure
The UFL will document and compare the supply of curb infrastructure being studied by the nine Collaborative cities and gather publicly available data sources to be used for comparative analysis. The UFL will incorporate information collected in Task 2 such as information about the study area, curb inventory, and if data allows compare curb allocation between study areas.

Task 4. Curb Policy
The UFL will document and compare curb policies among cities. Once documented, researchers will create a typology of curb-related regulations, strategies and technologies adopted in the past and proposed in the SMART Cohort. Researchers will incorporate data collected from cities in Task 2 and undertake additional research and policy scan as needed.

Task 5. Curb Demand
The UFL team will use data collected in Task 2 to assess if any of the Cohort cities are capturing curb-use data. For cities where this data is available, the UFL team will estimate curb use for selected study areas within the cohort of cities and perform a comparative analysis. The accuracy of the analysis will depend on the availability of data provided by the selected cities.