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United States Department of Transportation United States Department of Transportation

Cooperative Adaptive Cruise Control (CACC)

Project Information

Project ID:
Project Abstract:

The CACC project included two phases. Phase 1 was an analytical proejct. The goal of this  project was to develop and evaluate research methods to assess drivers’ acceptance and behavior when using CACC based upon specific scenarios derived a the mobility service concept. Phase 2 was  focused on human factors research to examine the effects of CACC on driver performance in a variety of situations. CACC has been envisioned as an automated vehicle application that complements the capabilities of the vehicle operator without degrading the vehicle operator’s alertness and attention.

Four experiments are summarized that were conducted in a driving simulator. Three of these experiments focused on the effects of CACC when drivers in a string of CACC-equipped vehicles had to respond to other drivers merging into the string or to rapid deceleration of the lead vehicle in the string. The remaining experiment focused on the human factors issues that arose when a driver merged into an existing string of CACC vehicles.


The objectives of this exploratory project are to:

(1) Define a small set of scenarios, based upon the base CACC concept of operations, that recognize differences in the way this concept can be realized. These scenarios will, in turn, identify a series of independent variables that, when compared to current conditions, provide a basis for describing driver behavior and other human factors issues associated with the concepts.

(2) Identify possible key drivers and other human factors issues that must be addressed in order to develop effective mobility services as outlined here.

(3) Frame the issues by creating specific research questions or hypotheses.

(4) Identify and describe, in detail, possible methods of answering these research questions.

(5) Outline specific requirements for human factors testing methods and equipment.

(6) Establish general requirements and estimate costs of additional resources needed at Turner-Fairbank Highway Research Center to conduct these tests.

(7) Identify other appropriate resources, including driving simulators and test tracks, that might be employed to conduct these studies, either initially or as a follow-up step.

Research HUB ID:
Project Status:
Project Funding Amount (Contract Award Amount):
Start Date:
End Date:
Public Access Plan:
  • Human Factors Laboratory
FHWA Program Area:
  • Exploratory Advanced Research
FHWA AMRP Program:
  • Safety Design and Operations
FHWA Activity:
  • Speed Management

Contact Information

Human Factors Team
Office of Safety Research and Development
Office Code:

Management Organizations

Sponsor Organization

Federal Highway Administration: Office of Research, Development, and Technology - Office of Safety Research and Development
Contact Role:
Project Lead

Managing Organization

Organization Role:
Project Managing Organization
Federal Highway Administration: Office of Research, Development, and Technology - Office of Safety Research and Development
Contact Role:
Project Contact

Performing Organization

Organization Role:
Performing Organization