车车通信模式下的车辆队列巡航安全性研究

With development of communication technology, the inter-vehicle wireless communication is applied to adaptive cruise control system. Traffic capacity is improved by shortening the inter-vehicle distance, but meanwhile vehicle safety problems are caused by communication invalid, communication distance or delay.The proposal focuses on vehicle platoon. The stability of vehicle platoon with VANets is studied and the impact of communication performance on vehicle platoon cruise safety is discussed.The proposal includes the following: Firstly, the vehicle cruise controller is designed based on the sliding model control method. the vehicle cruise stability that affected by the communication distance, transmission mode and communication delay is discussed, and the scope of headway between vehicles that satisfies the stability condition is calculated.Secondly, as the large-scale platoon is unstable in adaptive cruise control system, a new control stratagy for the large-scale platoon is proposed. The vehicles in large-scale platoon is grouped according to the new control strategy, and the maximum group size and the scope of headway between groups that satisfies the stability condition is established. Thirdly, by analysing inter-vehicle communication with partially invalid to the adaptive cruise control safety of large-scale platoon, the study presents the stability condition and safety control strategy of large-scale platoon. At last A cooperative collision avoidance algorithm is discussed under the condition that inter-vehicle distance too close.The study provides theoretical basis and key technical support for product designing of adaptive cruise control system with inter-vehicle wireless communication.

随着通信技术的发展，把无线通信引入车辆自适应巡航系统，有效缩短车间距离提高通行效率，同时由于通信的距离、延误或失效等带来车辆安全问题。本项目以车辆队列为研究对象，研究车车通信条件下的车辆队列稳定性问题，探讨通信性能对车辆队列巡航安全性的影响。本项目研究内容主要包括：设计基于滑模控制方法的车辆队列巡航控制器，探讨车间通信系统的通信距离、传输方式和信息延误对车辆队列巡航的稳定性的影响，确定满足稳定性条件的车间时距范围；针对在车车通信条件下大规模车辆队列巡航不稳定问题，提出车辆队列巡航分组控制策略研究，确定满足稳定条件的最大队列规模和组间时距范围；分析部分车辆通信失效对车辆队列巡航安全性影响，研究通信失效情况下的车辆队列稳定性问题和安全控制策略；探讨车间距过近状态下的协同避撞方法。该研究为具有车车通信功能的自适应巡航系统的产品研发提供理论基础和关键技术支撑。

本项目从提高车辆行驶安全性和保证车辆队列稳定性出发，主要完成了如下成果（1）针对传统车辆队列控制模型的计算复杂、难于实现的问题，项目将车辆动力学模型分层实现，并设计基于滑模控制理论的上层控制模型，通过仿真结果说明该模型满足实时控制需求；（2）针对车车通信失效和延时带来车辆队列控制安全性问题，项目建立了通信失效/延迟下的车辆队列协同控制模型，提出了相应的模型参数调整策略；（3）针对车辆队列车间距过小导致的车辆碰撞问题，项目提出了基于非线性规划理论的车辆队列协同主动避撞控制（CACA）模型，该模型可以在车间距小于制动距离时完成加速度分配，通过车辆队列中前后车协同控制来弥补车间距不足的安全隐患。（4）搭建了按1:10比例缩小的智能微缩车半实物仿真验证平台，沿用Buckingham的车辆“π groups”缩比模型法则和密歇根大学的模型车参数配置方法，分别对硬件、软件和道路环境按照相似比例进行设计，并搭建了半实物实验场景。项目设计的相关分析和验证方法，为车辆队列控制相关研究提供了理论基础和实验方法。