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Using Network Cellular Communications for Connected Work Zone Applications

ITS Arizona 2024 Annual Meeting

October 10, 2024�

David Lucas, Maricopa County Department of Transportation

Jeremy L. Schroeder, Ph.D., P.E., Athey Creek Consultants

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Direct vs. Network Communications

Vehicle-to-Everything (V2X) Direct Communications

5.9 GHz spectrum, formerly exclusively for dedicated short-range communications (DSRC)
Reallocated for Cellular-V2X (C-V2X) by the Federal Communications Commission (FCC)
Roadside units broadcast data for any receiver in range to receive
No ‘handshake’ for broadcaster to know who receives the data

Cellular Network Communications

The client (e.g., a web browser or mobile application) needs to initiate each interaction
Request-response model often uses the hypertext transfer protocol (HTTP)

Agencies publish and update XML feeds of road events
Applications receive updated information when they pulls the data
Alternatively, a publish-subscribe model is being demonstrated

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Arizona DOT Pilot

Connected Work Zone application messages issued based on Manual of Uniform Traffic Control Devices (MUTCD)
Broadcast audio and visual in-vehicle messages based on content and location of static signs

Pilot also examined back-of-queue warning and curve speed warning applications

Message 2

Message 1

Message 3

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Process for Using Network Cellular Communications for Connected Work Zones

Agency staff or systems report lat/long representing the start of a known work zone

Agency Linear Referencing System is queried to determine appropriate upstream locations

Agency software defines a data message for a notification at desired upstream locations

Agency publishes each data message to a cloud-based message broker

Mobile application subscribes to message broker and sends mobile app/vehicle location to edge computing servers via 4G/5G cellular communications

Verizon (or other carrier) message broker on the edge compares vehicle and agency-designated locations

When mobile app/vehicle location matches agency locations, the data message is delivered to the mobile app to alert the driver

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Arizona DOT Pilot

Demonstrated delivery of agency messages to a mobile application based on the position of the application

Leveraged new technologies and capabilities being developed by Verizon

Pilot replicated in-vehicle messaging as if there was a physical RSU, but without the need for field equipment

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Connected Vehicle Pooled Fund Study

The Connected Vehicle Pooled Fund Study (CV PFS) is a partnership of transportation agencies who have established a program to facilitate the development and evaluation of Connected Vehicle (CV) applications.

The program prepares state, local, and international transportation agencies for the deployment of CV technologies.

The program focuses on the following outcomes:

Development and demonstration of connected vehicle technology, algorithms, tools and applications
Preparation for field deployments
Development and deployment documentation
Lessons learned and identification of challenges from field deployments

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CV PFS Membership

Virginia DOT is the lead agency with technical/administrative support from the University of Virginia

Alaska, Arizona, California, Colorado, Connecticut, Delaware, FHWA, Florida, Georgia, Illinois, Maricopa County, Maryland, Michigan, Minnesota, New Hampshire, New Jersey, Ohio, Pennsylvania, Tennessee, Texas, Transport Canada, Utah, Virginia, and Wisconsin

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CV PFS Available Resources

Connected Intersections Guidance
MAP Guidance
Connected Intersection Message �Monitoring System (CIMMS)

https://engineering.virginia.edu/labs-groups/cvpfs

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Connected Vehicle Pooled Fund Study: �Connected Work Zone Project Purpose

Gather information and support deploying agencies

Arizona DOT, Caltrans, Maricopa County DOT

Develop Guidance materials based on these agency experiences to:

Enable DOTs to leverage available resources
Not limit approaches or restrict DOTs to using approaches that prevent interoperability or only favor one cellular carrier
Expand the Connected Work Zone vision beyond physical roadside units (RSUs)
Explain what is needed from IOOs for Connected Work Zones

Creation and delivery of data
Receipt of data from vehicles/applications
Testing and verifying the accuracy and delivery of messages

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Connected Vehicle Pooled Fund Study: �Connected Work Zone Project Activities

Coordination with Relevant National Standards Efforts
Document Arizona DOT Smart Work Zone Pilot
Provide Technical Support for California Connected Work Zone Deployment

Developed draft scope document

Conduct Assessment of Interoperability of Arizona and California Deployments
Develop Guidance Materials for IOO Deployment of Connected Work Zones

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Connected Vehicle Pooled Fund Study: �Connected Work Zone Project

Leveraging existing standards and informing agencies about enabling technologies and capabilities

SAE J2735 Traveler Information Message (TIM)

Protobuf

SAE J2540/2: ITIS Phrase Lists (International Traveler Information Systems)
Message Queuing Telemetry Transport (MQTT)
Mobile Edge Computing

Message Queuing Telemetry Transport (MQTT) - An OASIS standard for a mass text distribution portal that facilitates the sending of many messages in low-bandwidth environments.

Source: MQTT: The Standard for IoT Messaging (MQTT, n.d.)

Multi-access Edge Computing (MEC) (also referred to as Mobile Edge Computing) - Allows software applications to tap into local content and real-time information about local-access network conditions. By deploying various services and caching content at the network edge, mobile core networks are alleviated of further congestion and can efficiently serve local purposes. MEC also enables applications and services to be hosted ‘on top’ of the mobile network elements, i.e. above the network layer. These applications and services can benefit from being in close proximity to the customer and from receiving local radio-network contextual information.MEC moves the computing of traffic and services from a centralized cloud to the edge of the network and closer to the customer. Instead of sending all data to a cloud for processing, the network edge analyzes, processes, and stores the data. Collecting and processing data closer to the customer reduces latency and brings real-time performance to high-bandwidth applications.

SAE J2540/2: ITIS Phrase Lists (International Traveler Information Systems). This standard provides textual messages meeting the requirements for expressing International Traveler Information Systems (ITIS) phrases commonly used in the ITS industry. The codes within this standard were used in the ADOT pilot to communicate specific details about distance to the work zone and what lanes were closed, for example

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Connected Vehicle Pooled Fund Study: �Connected Work Zone Project

Demonstrate and test interoperability

Understand interoperability of Arizona and Caltrans systems and applications to recommend improvements, for these and future systems
Create test plan with assessment questions and describe activities
Summarize findings, changes for interoperability, and recommendations to enhance the application and interoperability

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Arizona efforts

SMART Stage 1 Planning Grant: $1.7M, Arizona Commerce Authority lead

Sept 1, 2023 – March 1, 2025
Build upon the success of the pioneering ADOT-MAG-Verizon pilot
Demonstrate the potential of next-generation Cellular Vehicle-to-Everything (C-V2X) applications using 4G/5G networks.

Back of Queue Warning
Work Zone Warning
Transit Signal Priority
Exploratory pilot for Vulnerable Road User (VRU) warnings

https://www.azcommerce.com/iam/projects/drive-arizona/

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Arizona efforts

USDOT Accelerating V2X Deployment Grant: $19.6M, MCDOT lead

Awarded June 2024
Relying primarily on 5.9 GHz communications

Connect 750 physical and virtual roadside units (RSUs) to…
Estimated 400 vehicle onboard units (OBUs) targeting transit, emergency and freight fleets.
Emergency Vehicle Preemption, Vulnerable Road User detection, Transit Signal Priority, and Freight Signal Priority
Cities of Phoenix, Tolleson, Avondale and unincorporated Maricopa County, as well as along ADOT’s US 60

https://highways.dot.gov/newsroom/usdot-awards-nearly-60-million-advanced-vehicle-technology-grants-arizona-texas-and-utah

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Looking to the future….

National efforts are working toward an interoperable, network cellular solution for providing connected work zone information

CV PFS Connected Work Zones
Utah DOT’s Connecting the West V2X Accelerator Grant

Goal is a seamless solution that is interoperable and consistent:

For IOOs to provide information
For drivers to receive it

And:

Across jurisdictional boundaries
For all network cellular carriers
Via different communications mechanisms

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Conclusion

Every agency will deploy and respond to new technologies at a different pace

Engagement and work being done now is important to ensure interoperability

Agencies are exploring and demonstrating new approaches that:

Leverage developed standards for direct communications
Leverage technologies available via network cellular communications
Leverage in-vehicle technologies that are already present (i.e., mobile devices)
Can be leveraged when cellular-V2X technologies are deployed

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For More Information

Jeremy Schroeder�Schroeder@acconsultants.org

David Lucas

David.Lucas@maricopa.gov

Connected Vehicle Pooled Fund Study

https://engineering.virginia.edu/labs-groups/cvpfs