A Roundabout Control for Connected and Automated Traffic

This research proposed a roundabout control for a single-lane roundabout when a connected and automated vehicle (CAV)’s market penetration rate is 100%. This system uses linear programming to optimize entering sequence for the global benefit (total delay minimization). A distributed consensus-based cruise control is designed for vehicles to enter the roundabout smoothly. The proposed roundabout control has the following features: it optimizes the movements of all vehicles for the global benefit. It is robust against unexpected situations, and also has an efficient cruise control to realize smooth coordination and can reduce abrupt braking under the premise of ensuring safety. A simulation-based evaluation proved that the proposed system is effective for mitigating performance degradation caused by heavy circulating flow and can improve roundabout capacity by about 50%. This system almost always avoids vehicles from stopping at the merging point. Delay benefits range from 91.5% to 97.6%. Fuel consumption benefits range from 0.6% to 57.5%. The variations are caused by different v/c ratios. The higher the v/c ratio, the greater the performance improvement.