基于自然驾驶数据的跨江大桥小客车跟驰特性研究

为明确跨江大桥的跟驰行为特征以及驾驶模式，在重庆菜园坝大桥展开了30位被试的小客车实车驾驶试验，使用华测航姿测量系统和前视碰撞预警系统Mobileye 630采集自然驾驶状态下汽车的连续行驶速度、车头时距和车头间距等数据。通过筛选得到了725条有效跟驰轨迹数据，对比分析发现跨江大桥与城市一般道路的跟驰行为存在一定差异性，明确了菜园坝大桥车头时距和车头间距的分布特征，并且对强跟驰(小于1.6 s)、过渡区间(1.6~2.6 s之间)以及弱跟驰(大于2.6 s)3种跟驰状态和驾驶人性别差异下的跟驰数据进行了分析。结果表明:桥梁段车头时距分布集中在1.6 s处，车头间距分布集中在18 m处;超过1/3的跟驰轨迹处于强跟驰状态，此状态下前车驾驶行为对跟驰车辆具有较强制约性;当车辆处于弱跟驰状态时，前车对于后车的约束性会随车头时距的增大而快速降低;过渡区间的设立更好地揭示了强/弱跟驰状态之间的转变并不是只有一个临界值，而是存在一个转换过程，并且其间车辆跟驰特性的变化与驾驶人本身的操作行为存在较大关联;驾驶人的性别差异对跟驰距离几乎没有影响，但男性驾驶人往往会采取更加冒险的驾驶行为，平均车头时距、车头间距以及相对速度均高于女性驾驶人。

Car-following Behavior of Passenger Cars on River Crossing Bridge Based on Naturalistic Driving Data

In order to clarify the car-following characteristics and driving patterns of the river crossing bridge, the field driving test of 30 drivers was carried out in Chongqing Caiyuanba bridge. The attitude measurement system and Mobileye 630 were used to collect the continuous driving speed, headway and space headway under the natural driving state.This paper obtained 725 effective car-following trajectory data through data screening,through comparative analysis and found that there are certain differences in the car-following behavior of the cross-river bridge and the general road in the city. Identified the distribution characteristics of the time headway and the space headway of the Caiyuanba Bridge, and analyzed the car-following data of different driver genders and three car-following states. The three car-following states refer to strong car-following (less than 1.6 s), transitional interval (between 1.6-2.6 s), and weak car-following (greater than 2.6 s). The results show that the distribution of the time headway of the bridge section is concentrated at 1.6 s, and the distribution of space headway is concentrated at 18 m. More than one-third of the car-following trajectories are in a strong car-following state. In this state, the driving behavior of the preceding vehicle is more mandatory for the car-following vehicle. When the vehicle is in a weak car following state, the restraint of the preceding car on the following car will rapidly decrease as the time headway increases. The establishment of the transition zone reveals that there is not only a critical value between the strong and weak car-following states, but there is a transition process, and The driver's own operating behavior will affect the change of the car following state. Driver gender have almost no effect on car-following distance, but male drivers tend to be more adventurous. Their average time headway, average space headway, and relative speed are higher than female drivers.