Cooperative Adaptive Cruise Control Small Scale Test- Phase 1: Final Report

Federal Highway Administration;Intelligent Transportation Systems Joint Program Office2017PDFTech ReportMeier, J.Abuchaar, O.Abubakr, M.Adla, R.Ali, M.Bitar, GeorgeIbrahim, U.Kailas, A.Kelkar, PKumar, V.Moradi-Pari, EhsanParikh, J.Rajab, S.Sakakida, M.Yamamoto, M.Deering, R.Crash Avoidance Metrics PartnershipVehicle-to-Infrastructure (V2I) ConsortiumUnited States. Department of Transportation. Intelligent Transportation Systems Joint Program OfficeUnited States. Department of Transportation. Federal Highway AdministrationUnited States. Department of Transportation. Intelligent Transportation Systems Joint Program OfficeUnited StatesAutonomous intelligent cruise controlDedicated short range communicationsLongitudinal controlPrototypesVehicle to infrastructure communicationsVehicle to vehicle communicationsConnected vehiclesAdaptive controlString-stabilityFHWA-JPO-18-617DTFH6114H00002Final reportThe focus of the Cooperative Adaptive Cruise Control \u2013 Small-Scale Test Project is to develop and implement CACC functionality as an extension of conventional ACC technology leveraging DSRC communications between vehicles and with the infrastructure. This report covers activities performed during Phase 1 of the research plan in which a reference ACC system was implemented in four prototype vehicles of different makes and models and baseline performance established through structured vehicle testing in a controlled environment. A simulation environment was established to model the behavior of vehicle strings under automated longitudinal control in freeway traffic. CACC algorithms were developed and evaluated in simulation, a preliminary hazard analysis was performed, and a safety concept was established for DSRC-enabled CACC. Specific technical goals for the project were to assess the ability of DSRC-enabled CACC to improve situational awareness, reduce system latency and optimize time gap. The proposed CACC system was implemented in simulation using BSMs with a small message extension containing additional necessary data elements. Acceleration forecasts played an important role in improving CACC performance. Overall it was shown that, through use of data exchanged via DSRC, improvements in string-stability may be realized. Reduced time gaps within a string of equipped vehicles may also be feasible, if close attention is paid to the additional functional safety requirements. These results were obtained in simulation and will need to be verified through vehicle implementation in Phase 2 of the research plan.119