Optimal Sequencing and Motion Control in a Roundabout With Safety and Comfort Guarantees

This paper develops a controller for Connected and Automated Vehicles (CAVs) traversing a single-lane roundabout so that it simultaneously determines (a) the optimal sequence and (b) the associated optimal motion control, jointly minimizing travel time, energy consumption and centrifugal discomfort while providing speed-dependent safety guarantees, as well as satisfying velocity and acceleration constraints. This is achieved by integrating (a) Model Predictive Control (MPC) to enable receding horizon optimization with (b) Control Lyapunov-Barrier Functions (CLBFs) to guarantee convergence to a safe set in finite time, thus providing an extended stability region compared to the use of standard Control Barrier Functions (CBFs). The proposed MPC-CLBF framework overcomes two important limitations of prior work on CAVs over multiple interconnected control zones in a traffic network: infeasibility and myopic control issues, while still providing safety guarantees. Simulations under varying traffic demands and roundabout configurations demonstrate the controller’s effectiveness and stability.