自动驾驶汽车在交通网络中的效能分析

Performance Analysis of Automatic Driving Vehicles in Traffic Network

研究了对于三车道的高速公路,自动驾驶汽车对混合交通流的通行能力及安全性的影响。引入变道欲望值、连续刹车率、空间速度方差和时间速度方差的概念,基于交通流元胞自动机模型,针对手动和自动驾驶2种汽车,建立了单向三车道的加减速和换道规则。选取6个评价参数,针对三车道模型,研究了随着自动驾驶汽车比例的增加,车道平均速度、平均速度的方差、交通密度、连续刹车率以及变道次数的变化情况。实验结果表明:在通行能力方面,当自动驾驶汽车的比例持续增加时,整个车道的平均速度、交通密度显著增加,从而大大提高了此交通网路中的通行能力;同时空间速度方差和时间速度方差会显著减少,说明整个交通流的平稳性增加了。在安全表现方面,当自动驾驶汽车的比例持续增加时,整个交通网路中的连续刹车率、变道次数先逐渐增加,然后逐渐减少,从而很好地刻画了安全性。最后分析了模型的优缺点,并指出了改进的方向。

The influence of the three-lane expressway and autopilot on the traffic capacity and safety of the mixed traffic flow is studied. Definitions of land-changing desire value, continuous braking rate, space velocity variance and time velocity variance are proposed. Based on the traffic flow cellular automata model, the acceleration / deceleration and lane-changing rules of one-way-three-lane are established for both manual and automatic driving. A total of six evaluation parameters are selected for the three-lane model,In view of the three-lane model, the variance of the average speed, the average speed, the traffic density, the continuous braking rate and the change of the number of changing lanes are studied with the increase of the proportion of the autopilot. The test results show that, as for the capacity of the traffic, when the proportion of automatic driving car continues to increase, the average speed of the entire lane and traffic density increased significantly,by contrast, the average speed variance significantly reduced, which greatly improving the traffic capacity in the trafficnetwork. At the same time, the variance of spatial velocity variance and time velocity will be significantly reduced, indicating that the smoothness of the whole traffic flow increases. In terms of safety performance, when the proportion of the automatic driving car continues to increase, the continuous braking rate in the entire traffic network, the number of change the first increase gradually, then gradually reduced,which is a good portray of the security. Finally, the advantages and disadvantages of the model are analyzed, and the direction of improvement is pointed out.