Speed Harmonization for Partially Connected and Automated Traffic

This paper proposed a speed harmonization controller for partially connected and automated traffic. It regulates the flow rate of the entire traffic by adjusting only the target cruising speed of Connected and Automated Vehicles (CAVs). The proposed controller bears the following features: i) compatibility enabled with partially connected and automated traffic consisting of CAVs and Human-driven Vehicles (HVs); ii) stability ensured for the traffic system under control; iii) precision guaranteed for the demand management on a multi-lane road with the help of a small portion of vehicles. To evaluate the proposed controller, a microscopic simulation evaluation was conducted. Results confirm that the control accuracy of the proposed controller is generally over 80% across all CAV Penetration Rates, demand levels (v/c ratio) and target demand drops (within 20%). A case study is presented to demonstrate the benefit of applying the proposed controller on a bottleneck. By preventing the onset of a breakdown and, along with it, a capacity drop, the proposed controller is able to increase the flow rate by 6%, reduce the number of stops by up to 90% and delay by approximately 5%.