【基于信息交互的元胞自动机车辆换道行为模型研究】元胞自动机模型范文.docx

基于信息交互的元胞自动机车辆换道行为模型研究】元胞自动机模型 摘要:相关车辆间的信息交互可能会对车辆换道过程中待换道车辆的决策产生较大影响基于车辆换道行为过程中的不同情形,考虑待换道车辆换道意图产生与换道行为实施的时间关系,建立综合性的车辆换道模型,该模型下车辆在不同条件时将分别执行自由换道及信息交互式换道仿真中通过改变交通流密度和目标车道后车加速概率,结果表明,相对于其它换道模型,新模型使整个路段的交通流平均速度变大,在一定程度上能够减少路段交通拥阻,提高路段通行能力,新模型中换道行为规则更符合实际交通流状态 Abstract: The course of vehicle lane-changing behavior not only depends on the decision-making of vehicle ready to change lane, but also relates to information interaction between the vehicle ready to change lane and the rear vehicle on the target lane. Based on different situations of vehicles’ lanes-changing process, the time relation between lane-changing intention appearance and lane-changing action implementation is considered, and the comprehensive lane-changing model is built. Respectively, the free lane-changing or lanes-changing from information interaction is executed under different conditions. By changing traffic flow density and the acceleration probability of the rear vehicle on target lane, simulation results showed that the average speed of whole road section was improved in the new model, and road traffic congestion was relieved. The vehicle lane-changing rules in the new model are more in line with real traffic flow state. 关键词:元胞自动机 换道行为 换道意图 信息交互 Keyword: cellular automatalane-changing behavior lane-changing intention information interaction 1 Foreword The transportation simulation is an effective tool in studying transportation system evolution characteristic and control policy. In recent years, do transportation simulation using the model of cellular automata, and then show different tendency of traffic flow under different conditions, has been one way used by numerous researchers, because of the discrete and non-liner characteristics owned by transportation system[1][2][3][4]. Individual vehicles is as the fundamental research object in cellular automaton transportation model hands, its movement renewal rules can be revised nimbly, finally the simple microscopic rule execution emerges the macroscopic transportation phenomenon, thus this kind of model has the incomparable superiority in the description actual transportation phenomenon process. In the research of lane-changing rules, an important model is the symmetrical double-lane cellular automaton model which is proposed by Chowdhury (STCA model) [5], in the STCA model"s foundation, the researchers make various improvements according to the actual vehicles behavior, Reference [6] proposed a kind of fuzzy control traded model, using the fuzzy reasoning to simulate the human’s subjective judgment process in the process of changing lane; Reference [7], proposed a more nimble elasticity lane -changing rule, which is based on pilot"s disposition difference, and discussed the influences to every parameter in different lane-changing models. Reference [8] thinks in the actual transportation, because lane-changing vehicles" moving velocity is different, its needs different security lane-changing interval, therefore it proposed cellular automaton model based on elasticity and safety lane-changing interval. 2 Mathematical Model In actual transportation environment, when vehicles change its lane, it will turn on the steering lamp in order to prompt vehicles after the goal vehicle. According to the differences of (distance between the lane-changing vehicle and vehicle after it in goal lane ) and( vehicle"s velocity in goal lane which is after the lane-changing vehicle), lane-changing behavior will generally have following several situations: ①When lane-changing vehiclethink thatandis safe enough to change its lane,turn on the steering lamp while changing to the goal lane, in this situation,belongs to free change,andis thought that they didn"t have mutual information, this is shown in Fig.1; ② When lane-changing vehicledon"t think thatandis safe enough to change its lane, andwant to try it,turn on the steering lamp but don"t change to the goal lane, and move on, watch the reaction of , which will have two kinds of reaction: speed up or move on in its primary speed,don"t want to change to the goal lane; the second situation is thatreduces its speed, in this situation, will do next step. Through the above analysis, we know that under this kind of traffic condition, in the process of changing laneandhave the mutual information, therefore, when establish the lane-changing model we must consider the movement behavior of . This situation is shown in Fig. 2. In the first situation, considering the safe of changing path, here we use converted STCA model as the model[7] of vehicles" changing lane,which is as follows: (2-1)our model respectively means the distance between vehicle n and the vehicle before it、the distance between vehicle n and the vehicle before it in adjacent lane、the distance between vehicle n and the vehicle after it in adjacent lane; means the lane the vehicle n in, and = 1 or 0.means vehicle n is hold ba。