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CARMA Program Overview

Developed by the Federal Highway Administration (FHWA), the CARMASM Program uses a multimodal approach to encourage collaborative research on the technology, open source tools, and frameworks poised to improve transportation system mobility, safety, and efficiency.

The CARMA Program is leading research on cooperative driving automation (CDA), leveraging emerging capabilities in automation and cooperation to advance transportation systems management and operations (TSMO) strategies.

The following video provides a high-level overview of the CARMA Program ecosystem.

Cooperative Driving Automation

Defined by the Society of Automotive Engineers (SAE) J3216 Standard, CDA enables communication and cooperation between properly equipped vehicles, infrastructure, and other road users.

CDA is defined in J3216 as having four classes of cooperation, A through D, with an increasing amount of cooperation associated with each successive class:

  1. Class A: Status-sharing.
  2. Class B: Intent-sharing.
  3. Class C: Agreement-seeking.
  4. Class D: Prescriptive.

Information shared among CDA participants can directly influence the dynamic driving task (DDT) by one or more nearby vehicles with driving automation feature(s) engaged. Ultimately, CDA-enabled cooperation can facilitate the safer and more efficient movement of road users, which can significantly improve the overall performance of the transportation system—and at lower cost than traditional methods.

The introduction of CDA will provide essential solutions to the biggest challenges facing transportation. From reducing congestion, collisions, pollution, and energy consumption, to enhancing road user safety, traffic flows, and operational efficiency, CDA is poised to transform the Nation’s roads.

CARMA Program

The CARMA Program is spearheading the research and development (R&D) of CDA concepts in support of TSMO. The program employs an open source software (OSS) approach, coupled with agile development practices, to develop and test CDA features involving infrastructure, properly equipped vehicles, and other road users.

" fleet of 5 CARMA vehicles"

Source: FHWA.

Figure 1. Photo. Passenger vehicles and heavy truck from the CARMA research fleet.

The CARMA Program is uncovering opportunities to use CDA to improve transportation system safety and performance through an ecosystem of products, research tracks, evaluation tools, and engagement strategies.

"CARMA products icon."


"CARMA research tracks icon."

Research Tracks

"CARMA evaluation icon."


" CARMA engagement icon."


The CARMA Program examines all users in the transportation system and fosters collaborative research to accelerate advancements in pilot transportation technologies. Through this critical work, the FHWA aims to harness CDA concepts to improve the safety and mobility of millions of Americans.