CACC车辆跟驰建模及混合交通流分析

建立协同自适应巡航控制(Cooperative Adaptive Cruise Control，CACC)车辆跟驰模型，并分析不同CACC比例下的混合交通流通行能力，尾部碰撞安全及交通排放.考虑车辆期望车头间距随速度动态变化的交通流特性，建立基于非线性动态车头间距策略的CACC跟驰模型，推导不同CACC比例下的混合交通流基本图模型，分析CACC提高通行能力的交通流运行机理.设计高速公路上匝道瓶颈数值仿真实验，评估不同CACC比例下的车辆尾部碰撞安全隐患，以及油耗、CO、HC、NOx的排放.研究结果表明，本文建立的CACC模型能够在交通流速度基本不变的情况下，以较高的交通流密度显著提升通行能力，同时有利于车辆尾部碰撞安全风险及交通排放的降低.

Car-following Modeling for CACC Vehicles and Mixed Traffic Flow Analysis

A Car-following model of cooperative adaptive cruise control (CACC) vehicles is built. At the same time, capacity, rear- end collision safety, and traffic emissions of the mixed traffic flow are also analyzed under different CACC proportions. By considering the traffic flow characteristics that desired headways of vehicles change dynamically with respect to speeds, the non- linear dynamic headway policy based CACC model is presented. Then, the fundamental diagram model of the mixed traffic flow is derived under different CACC proportions, in order to analyze traffic flow operation mechanism which improves capacity. Numerical simulations are designed near bottleneck of the freeway with an on- ramp, based on which rear- end collision risk, fuel consumption, CO, HC, and NOx are evaluated. Research results show that the presented CACC model can have high traffic flow density to improve capacity obviously for the case in which speeds are basically not changed. Moreover, CACC benefits the decrease of rear-end collision risks and traffic emissions.