## Multi-objective optimal cooperative driving for connected and automated vehicles at non-signalised intersection

The problem of cooperative driving for the connected and automated vehicles (CAVs) at the non-signalised intersection is addressed in this study. The conceptions of conflict point and intersection layout are used to formulate the mathematical model of the non-signalised intersection. Based on this model, a novel cooperative control algorithm is proposed for the CAVs driving at the non-signalised intersection. In the cooperative algorithm, the high-dimensional problem of multi-CAV cooperating at multi-conflict points is expediently converted into the single-dimensional problem of searching the optimal time for current CAV to enter the intersection. Then the analytical solution based on Pontryagin's minimum principle considering constraints of vehicles is used to control the CAVs at the intersection area. In addition, the modification of the switching input is used to reduce the CAVs’ jerk. With the cooperative control algorithm, the multi-objectives are considered including guaranteeing CAV safety, alleviating traffic congestion, and improving the performance of fuel consumption. In particular, the low-computational characteristic of the proposed algorithm guarantees that each CAV can get the optimal solution quickly and effectively. Simulation results verify that the proposed algorithm is capable of achieving coordination of CAVs with the various speeds at the non-signalised intersection.