Coordinated control of road internal boundary and lane changes of connected autonomous vehicles on freeways of mixed autonomy

This paper addresses lane-free traffic of connected autonomous vehicles (CAVs) under a mixed-autonomy condition on freeways. It introduces an integrated control method that combines road internal boundary control (IBC) and active lane-changing control (LCC) for CAVs. To cope with the coexistence of CAVs and human-driven vehicles (HVs), a dedicated bidirectional zone is established for CAVs in the center of the considered freeway, which is operated in the lane-free mode in either direction. IBC is considered within the dedicated zone of CAVs. The rest of space in either direction is shared by CAVs and HVs, and an LCC strategy is applied to regulate the lane-changing flow of CAVs between the dedicated zone and mixed area in either direction. A model predictive control (MPC) framework is adopted to coordinate IBC and LCC of CAVs, for the sake of optimizing road space utilization and traffic flow efficiency. The study results demonstrate that the proposed control method is able to achieve the control goal.