This paper focuses on evaluating, in a structured manner, the potential benefits, along with the implementation and performance issues, of utilizing dedicated short range communication-based communication in conjunction with adaptive cruise control (ACC) systems. This work was done in the United States under a cooperative agreement between the Crash Avoidance Metrics Partners LLC and the Federal Highway Administration. Designing cooperative adaptive cruise control (CACC) as an extension of ACC, and by using a combination of a comprehensive simulation framework and test vehicles, benefits of vehicular communication on string stability were established, and the performance of the novel CACC-enabling software modules were validated. Another key contribution of this work is the consideration of vehicles with different dynamic responses as a part of a single string. Four light-duty vehicles (hatchback, mid- and full-size sedans, large SUV), each from a different automotive original equipment manufacturer, were retrofitted with common ACC and vehicular communication systems. They were tested under many different conditions to obtain performance data (such as radar sensor readings, etc.) when operating in a vehicle string. These data were then integrated into the simulation environment to develop and validate the CACC modules. The paper concludes with a recommendation of some data elements for over-the-air messages to enable CACC functionality.
