网联自动驾驶技术的出现与发展为解决城市交通问题带来了巨大的机遇。着眼于城市交通控制面临的车流冲突关系复杂、交通流量分布不均、异质车辆差异较大等问题，本文提出了一种面向网联自动驾驶环境的城市道路交通“节奏式”控制方法，旨在提高城市交通运行效率与安全性。从节奏式控制的基础模型到面向各类城市交通场景的节奏式控制方法延拓，本文主要工作包括以下四个方面：（1）提出了路口级节奏式控制的基础模型。深入分析了车流冲突关系与冲突点布局、车辆通行轨迹之间的耦合机理，提出了将道路空间组织与交通控制策略联合设计的方法。引入虚拟厢的概念以规范车辆的通行轨迹，协同优化虚拟厢时空轨迹与交叉口空间布局，实现了交叉口通行权的精细划分与道路时空资源的充分利用。经测试，在交通饱和度达到90\%时，交叉口的平均车辆延误不超过10秒。（2）提出了路网级节奏式控制的进阶设计方法。考虑由多个交叉口组成的城市路网，提出了纽结型交叉口布局设计以简化车流冲突关系，构建了多交叉口协同设计方法，应用二相位控制策略实现了通行能力的近似最大化。联合道路组织设计、网络交通流量分配与车辆轨迹优化问题，构建了路网级节奏式控制方案的优化模型。实验结果显示，在节奏式控制下路网吞吐量可达传统信号控制的两倍。（3）提出了面向不均衡交通需求的多重节奏式控制方法。基于交通流量分布特性设计差异化控制周期，针对不同车辆通行特性提出多样化虚拟厢设计，并考虑车道配置与交通流量分配问题构建了联合优化模型，实现了对异质交通的协同组织与有效控制。经测试，在各类交通需求分布场景下，该方法均能够降低车辆通行成本，同时提高路网通行能力。（4）提出了面向多模式交通的异步节奏式控制方法。考虑由公交车与小汽车组成的多模式交通，针对公交车通行优先级提出专用虚拟厢设计，并结合公交车行程规划问题、小汽车流量分配问题进行联合优化。实验结果显示，该方法在保证公交车通行优先性的前提下，减少了对小汽车通行效率的负面影响，提高了多模式交通的总体运行效率。整体而言，本文以节奏式控制为核心，按照“机理分析-模型构建-仿真验证”的主线展开研究，构建了一个完整的面向网联自动驾驶环境的城市交通控制方法体系，在解决当前城市交通问题、适应未来城市交通发展上具有重要的参考意义。
The rapid development of connected and automated technologies brings great potential for advanced urban traffic control. Considering the traffic problems of complicated conflict relations among vehicular movements, imbalanced distribution of traffic flows, and incompatibility of heterogeneous vehicles, this dissertation aims to develop an innovative rhythmic traffic control approach under a connected and automated vehicle environment to improve traffic efficiency and safety. To achieve the research objectives, this dissertation begins with the fundamental concept and model of rhythmic traffic control, extends to various methods for different traffic scenarios. The main contents are summarized as follows:(1) The novel and fundamental rhythmic traffic control philosophy is proposed for single intersections. By in-depth examining the relationship of vehicular conflicting movements, the road geometric layout and traffic control strategy are designed in a unified framework. The concept of virtual container is introduced to organize traffic in a highly-orderly manner, and jointly optimized with the intersection geometric layout, so the right-of-ways of intersection could be finely assigned and the space-time resources could be fully utilized. The approach could reduce the average vehicular delay to below 10 seconds when the traffic saturation level reaches 90%.(2) The fundamental rhythmic traffic control strategy is extended over an urban network. A knotted intersection design is proposed to simplify the conflicting relations, and collaborated among adjacent intersections. The two-phase traffic control strategy is developed and achieves the nearly-optimum throughput of intersections. The knotted intersection design, space-time trajectories of virtual containers and network traffic flow assignment are jointly optimized to build up a network-level traffic control optimization model. The results show that the maximum traffic volume under rhythmic control strategy is twice as much as that under traditional signal control.(3) The multiple rhythmic traffic control approach is proposed for an urban network with imbalanced traffic distribution. Differential control rhythms are adopted for different areas according to the flow distribution, and various virtual containers are designed for different types of vehicles. Collaborated with lane configuration and traffic flow assignment, a joint optimization model is developed for the heterogeneous traffic control. The approach could reduce vehicular travel cost and improve network throughput under various demand cases.(4) The asynchronous rhythmic traffic control approach is proposed for the multi-mode traffic with transit buses and private cars. Dedicated virtual containers are designed for transit buses to provide priority of right-of-ways, and the travel itinerary planning of buses and the traffic flow assignment of private cars are jointly optimized. The results show that under the premise of priority treatment for buses, the approach could eliminate the efficiency damage for private cars and enhance the overall traffic efficiency.On the whole, this dissertation focuses on rhythmic traffic control, and follows the main line that begins with fundamental philosophy, optimization models, and ends with simulation validation, and develops a complete solution of urban traffic control approach under the connected and automated environment. The proposed approaches are expected to provide important reference significance for solving the current traffic problem and adapting to the future traffic development in urban cites.
