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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation
OFFICE OF RESEARCH, DEVELOPMENT, AND TECHNOLOGY AT THE TURNER-FAIRBANK HIGHWAY RESEARCH CENTER

Preferred Following Distance as a Function of Speed—Function-Specific Automation (Level 1) Applications

FHWA-HRT-22-107.pdf (755.3 KB)

Publication Information

Publication Type:
Technical Report
Publication Number:
FHWA-HRT-22-107
Abstract:

This report documents an experiment aimed at identifying comfortable gap distances used in adaptive cruise control (ACC) and cooperative adaptive cruise control (CACC) systems. This study used a variety of speeds that could be used to help guide set speeds for these systems. Participants drove an experimental course that included nine test speeds. The participants comfortable and minimally safe following gaps were recorded as they drove manually, and they rated their comfort level with the ACC gap distance at the same locations and speeds. The result was a creation of a set of comfortable and minimally safe following gap curves that were compared to the gap distance curve of an ACC system currently on the market.

 

This report is of interest to transportation engineers and researchers, ACC developers, State and local transportation agencies, and other roadway safety professionals interested in understanding how ACC and CACC systems will affect drivers and roadway safety.

 


 

Recommended citation: Federal Highway Administration, Preferred Following Distance as a Function of Speed—Function-Specific Automation (Level 1) Applications (Washington, DC: 2021) https://doi.org/10.21949/1521938.

Publishing Date:
December 2022
Posting Date:
Digital Object Identifier:
https://doi.org/10.21949/1521938
Author(s):
Weaver, Starla (ORCID: 0000-0002-9559-8337)
Chao, Szu-Fu (ORCID: 0000-0002-2037-5200)
Jannat, Mafruhatul (ORCID: 0000-0002-5218-3051)
Philips, Brian
Publishing Office:
Safety Data and Analysis Team
FHWA Program(s):
Safety
Research
Human Factors
AMRP Program(s):
Human Factors Analytics
FHWA Activities:
Data and Analysis
Human Factors
Roadway Safety Capacity Building Program
Subject Area:
Safety and Human Factors