考虑加速度衰减效应的网联车跟驰建模与仿真

Modeling and Simulation of Connected Vehicles Following Considering Acceleration Attenuation Effect

为研究未来道路上存在的由网联车(CVs)和普通人工驾驶车辆组成的混合交通流跟驰特性,在智能驾驶员模型(IDM)的基础上,考虑接收到的前车加速度信号衰减效应,类比信号塔信号强度与距离的反比关系,构建基于V2V的网联跟驰车辆间的信号传输模型。基于IDM模型对网联车构建加速度信号衰减的跟驰(AACF)模型,利用V2V环境下的城市道路跟驰数据对模型中参数进行标定以及修正。此研究选取优化速度模型(OVM)作为人工车跟驰模型,AACF作为网联车车跟驰模型,设计数值仿真试验。为了能够测试网联人工混合车流的队列稳定性,在数值仿真试验中人工加入了头车的速度扰动。此研究在头车速度随机扰动的情况下,对于不同网联车渗透率随机分布的混合交通流队列跟驰稳定性进行了测试。利用了MATLAB进行数值仿真试验,并通过X-T与V-T图像进行不同网联车渗透率情况下的队列跟驰行为分析。结果表明:在头车进行相同扰动的前提下,不论头车在加速还是减速过程中,AACF跟驰队列的速度最大极差均比IDM的小,这表明AACF模型更能体现网联车的驾驶特性。对于混合交通流,随着网联车渗透率的增加,交通流的速度扰动减小,安全系数提高;且当网联车渗透率达到0.6时,混合交通流可以处于稳定的驾驶状态;且在网联车渗透率超过0.6后,混合交通流的稳定性趋于稳定。

To study the mixed traffic flow car-following characteristics consisting of connected vehicles(CVs)and regular vehicles on the road in the future,based on the intelligent driver model(IDM),the attenuation effect of received front-vehicle acceleration signal was considered;and the inverse relation between signal strength and tower distance was compared.The V2V-based signal transmission model among CVs was constructed.The acceleration attenuation car following(AACF)model was constructed for CVs.The model parameters were calibrated and corrected by using the urban road car-following data in V2V environment.The numerical simulation experiment was designed.The optimal velocity model(OVM)was selected as the regular vehicles following model,and the AACF was selected as the CVs following model.To test the queue-stability of mixed traffic flow,the velocity disturbance of the lead vehicle was artificially added in the experiment.In the case of lead vehicle velocity random disturbance,the following stability of mixed traffic flow queue with different CVs’permeability random distribution was tested.MATLAB was used to carry out the numerical simulation experiment.X-T and V-T images were used to carry out the queue following analysis with different CVs’penetration rates.The result indicates that on the premise of same disturbance of lead vehicle,the speed disturbance amplitude of AACF is smaller than that of IDM,no matter the lead car is accelerating or decelerating.It indicates that AACF can better reflect the driving characteristics of CVs.For the mixed traffic flow,the velocity disturbance decreases and the safety index increases with the increase of CVs’permeability.When the CVs’penetration rate reaches 0.6,the mixed traffic flow can be in a stable driving state.When the CVs’penetration rate exceeds 0.6,the stability of mixed traffic flow tends to be constant.