Modeling cooperative and autonomous adaptive cruise control dynamic responses using experimental data

Abstract

Vehicle longitudinal control systems such as (commercially available) autonomous Adaptive Cruise Control (ACC) and its more sophisticated variant Cooperative ACC (CACC) could potentially have significant impacts on traffic flow. Accurate models of the dynamic responses of both of these systems are needed to produce realistic predictions of their effects on highway capacity and traffic flow dynamics. This paper describes the development of models of both ACC and CACC control systems that are based on real experimental data. To this end, four production vehicles were equipped with a commercial ACC system and a newly developed CACC controller. The Intelligent Driver Model (IDM) that has been widely used for ACC car-following modeling was also implemented on the production vehicles. These controllers were tested in different traffic situations in order to measure the actual responses of the vehicles. Test results indicate that: 1) the IDM controller when implemented in our experimental test vehicles does not perceptibly follow the speed changes of the preceding vehicle; 2) consecutive strings of ACC vehicles are unstable, amplifying the speed variations of preceding vehicles; and 3) consecutive strings of CACC vehicles overcome these limitations, providing smooth and stable car following responses. Simple but accurate models of the ACC and CACC vehicle following dynamics were derived from the actual measured responses of the vehicles and applied to simulations of some simple multi-vehicle car following scenarios.

Influence of CAV clustering strategies on mixed traffic flow characteristics: An analysis of vehicle trajectory data

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“…The conflict rate, which is derived from the vehicle interactions between AV and HV at each simulation time step, was used as a safety indicator among nine levels of CAV aggressiveness. However, the performance of each vehicle group was not separated, and the efficacy of simulating AV behavior by merely adjusting the Wiedemann model is still subject to debate (Milans and Shladover, 2014).…”

Delayed Feedback MPC Algorithms of Vehicle Platoons Subject to Constraints on Measurement Range and Driving Behaviors

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Modeling and simulations on automated vehicles to alleviate traffic congestion

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