为提高高速匝道入口车辆合流安全性与通行效率,减少燃油消耗,提出了面向高速匝道入口的多智能网联车辆最优纵向轨迹规划方法,以实现车辆的协同合流.首先,建立车辆纵向动力学模型,考虑能量效率与乘坐舒适性构造代价函数,构建入口匝道的车辆最优车速控制问题;同时,基于先进先出的合流次序,设计各相邻车辆到达合流点的时刻与时间间隔,实现安全与高效的协同合流.利用庞特里亚金极小值原理求解车辆最优车速控制问题,推导出各车辆纵向速度的最优解析解.仿真结果表明:与无控制自然合流相比,所提出控制方法通行时长缩短41.64％,燃油消耗降低12.25％;与现有基于虚拟队列的控制方法相比,通行时长相差1.67％,燃油消耗降低4.52％.

The on-ramps traffic for merging of main road and secondary road will lead to congestion under heavy traffic conditions. Connected and automated vehicles (CAVs) are recognized as one of the techniques which could improve traffic capacity, safety and fuel efficiency. This paper proposes a cooperative merging strategy which projects the approaching vehicles on the secondary road onto the main road to form a virtual vehicle platoon Bi-directional communication topology is used to achieve the vehicle inter-communications. In addition, the distributed controller based on feedback linearization method is designed to ensure the inner-vehicle closed-loop stability for virtual platoon with derived feedback gains. The merging simulations at highway on-ramps show stable platoon and smooth merging for multiple CAVs before the merging point.

Vehicle platoon is a typical application of connected and automated vehicle, and known for its energy saving potential because smaller inter vehicle spacing implies less aerodynamic drag. However, the regular platooning control method may lead redundant energy consumption because unnecessary vehicle acceleration and deceleration of the following vehicles may occur for the purpose of tracking leading vehicle's velocity precisely. To improve the energy efficiency of platoon operation, this paper proposes an energy-efficient control strategy for homogeneous platoon on highway with varying slopes. The range of control gains for the state feedback controller is derived based on the string stability analysis. The optimal control gains are calculated by using genetic algorithm (GA). The simulation results for a platoon with five electric vehicles indicate 2.213% energy consumption reduction can be achieved by optimizing the control gains on terrain road.