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                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:01/04/2023
                              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
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              Subject Area:Safety and Human Factors U.S. DEPARTMENT OF TRANSPORTATION

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