Connected Automated Vehicles Entry Capacity on Roundabouts- Case Study Hungary

This study delves into roundabout entry capacity in Hungary, introducing a new model emphasizing the impact of circulating flow and geometric variables. The relationship between estimated entry capacity and various circulating flows and geometric factors is expressed multiplicatively. Central island diameter and splitter island width are identified as key factors, surpassing others. Comparisons with European models validate the new model's reliability, especially at low circulating traffic levels. Additionally, the study explores Connected and Autonomous Vehicles (CAVs) effects on single-lane roundabout capacity. Using adjustment factors from the 2022 Highway Capacity Manual (HCM), the study estimates entry capacity for varying CAV penetration levels, revealing significant increases as CAV levels rise with R2 of 0.723. Central island diameter and splitter island width notably contribute to these increases.