Optimization based trajectory planner for multilane roundabouts with connected automation

Abstract

This paper proposes a trajectory planner for multilane roundabouts. The goal is to enhance the existing roundabout in terms of capacity with the help of connected automation. The trajectory planner is formulated as a bi-level optimization. The upper level is a passing sequence optimization, which determines the passing sequence of the approaching vehicles to achieve delay minimization. The lower level is a speed optimal control aiming at minimizing fuel consumption while honoring the pass sequences generated from the upper level optimization. The proposed planner is evaluated in simulation on a typical four-arm roundabout with two entrance lanes in each arm. Compared with the traditional yield-regulated control, the proposed approach can reduce the delay by 69.6% to 87.8% and fuel consumption by 24.7% to 28.6%. Compared with the first-come-first-service (FCFS) control, the proposed approach can reduce the delay by 33.5% to 81.9% and fuel consumption by 7.5% to 18.8%. The change in benefit is due to the variation of demand.