【作者】 李凡；

【导师】 陈韬； 张宏超；

【作者基本信息】 天津大学 ， 工程（专业学位）， 2021， 硕士

【摘要】 作为自适应巡航控制(Adaptive Cruise Control,ACC)技术的延伸,协同式自适应巡航(Cooperative Adaptive Cruise Control,CACC)在结合车车通讯技术的基础上,能够实现更为便捷和快速的队列成员行驶状态信息获取,稳态行驶状态下的CACC队列控制对交通效率的改善和经济性具有重大意义。而决定协同式自适应巡航控制系统工作表现的主要因素为期望跟驰间距的设定和车速控制方法的设计,为了提高队列控制下的车距稳定性,本文提出了一种基于势场改进可变车头时距(Variable Time Headway,VTH)策略和扰动补偿模型预测控制方法的协同式自适应巡航控制策略。本文提出了一种基于人工势场法的VTH改进策略,用于提高期望车距的实时性和精确性。首先,以两辆前导车的跟驰误差为参考建立前车势场,通过行驶状态分析对势场中车辆势能高低进行甄别,最终落实为作用于被控本车的势场力,通过分析多前车产生的势场作用,并将其推广到队列后方,最后通过归一化方法确定综合势场作用方向和大小,并以此对VTH策略作出改进。通过Simulink与Carsim平台的联合仿真,验证了改进后策略对车距跟踪稳定性的优化效果。结果表明,根据前车跟驰误差建立的引斥力势场能够加快被控本车的响应速度,降低车距超调,并且能够提高0.667m的车距控制精确度。在车速控制算法部分,以安全性、跟驰效率、驾乘舒适性以及能耗经济性建立目标优化函数,并结合扩张状态观测器(Extended State Observer,ESO)设计基于扰动补偿的模型预测控制方法,并在Matlab/Simulink-Driving Scenario Designer仿真场景中通过算法对比对车距控制效果进行了验证。实验结果表明,增加扰动补偿后的算法车距和车速波动分别降低了25.8%和48.4%,证明了算法对跟驰稳定性的改善效果。更多还原

【Abstract】 As an extension of Adaptive Cruise Control(ACC)technology,Cooperative Adaptive Cruise Control(CACC)can achieve more convenient and fast acquisition of platooning members’ driving state information on the basis of vehicle-to-vehicle communication technology.The CACC platooning control in steady-state driving state is of great significance to the improvement of traffic efficiency and economy.The main factors that determine the performance of cooperative adaptive cruise control system are the setting of expected following distance and the design of vehicle speed control method.In order to improve the stability of vehicle distance under platooning control,this paper proposes a cooperative adaptive cruise control strategy based on potential field to improve Variable Time Headway(VTH)strategy and disturbance compensation model predictive control method.In this paper,firstly,an improved VTH strategy based on artificial potential field method is proposed to improve the real-time and accuracy of the desired distance.Firstly,the following errors of two leading vehicles are taken as reference to establish the potential field of the preceding vehicles,and the potential energy level of the vehicles in the potential field is discriminated by driving state analysis,which is finally implemented as the potential force acting on the controlled vehicle.By analyzing the potential field generated by multiple preceding vehicles,it is extended to the rear of the platooning.Finally,the direction and size of the comprehensive potential field are determined by normalization method,and the VTH strategy is improved.Through the joint simulation of Simulink and Carsim platform,the optimization effect of the improved strategy on the stability of distance tracking is verified.The results show that the repulsion potential field established according to the following error of the preceding vehicle can accelerate the response speed of the controlled vehicle,reduce the overshoot of the vehicle distance and improve the control accuracy of the vehicle distance of 0.667 m m.In the part of speed control algorithm,the objective optimization function is established with safety,car-following efficiency,ride comfort and energy consumption economy,and the model predictive control method based on disturbance compensation is designed with Extended State Observer(ESO),and the control effect of distance between vehicles is verified by algorithm comparison in MATLAB/Simulink-driving scenario designer simulation scene.Experimental results show that the distance between vehicles and the fluctuation of vehicle speed are reduced by 13.5% and 32.3% respectively after adding disturbance compensation,which proves that the algorithm improves the following stability.更多还原