基于贝叶斯博弈的自动驾驶车辆换道预测模型

Lane-changing prediction model of autonomous vehicle based on Bayesian game

在混合交通环境下,人类驾驶员换道目标车道的驾驶风格,是自动驾驶车辆博弈建模过程中的不完全信息,导致自动驾驶车辆无法预测人类驾驶员的驾驶决策。本文提出了一种解决博弈参与者间不完全信息的贝叶斯博弈换道预测模型。首先,使用车辆加速度主观感受评估模型,得到目标车道人类驾驶员驾驶风格的初始量化值,并用于贝叶斯博弈换道模型中人类驾驶员状态空间的置信度。其次,使用基于分子动力学模型的期望安全距离求解博弈安全收益。最后,将贝叶斯博弈转化为完全信息静态博弈求解纳什均衡,通过对比人类驾驶员预测动作和实际动作的匹配度,结合驾驶风格量化指标修改其状态空间评估置信度。仿真结果表明:与K级博弈模型和具有鲁棒性的K级博弈改进模型相比,在相同的交通环境中,采用更严格的碰撞率统计标准,贝叶斯博弈模型的碰撞率为2%,远低于K级博弈的13%和鲁棒模型的7%,三种博弈模型在3.5秒内完成换道的占比分别为93%,92%和69%。本文所提换道模型在自动驾驶车辆决策风险控制上具有更好的效果,在合理时间范围内的换道效率也可以得到保障。

The driving styles of the human vehicles(HVs)in the lane-changing target lane are incomplete information for the game modeling process of the autonomous vehicles(AVs),making it difficult for AVs to predict the driving decisions of HVs.A Bayesian game lane-changing prediction model is proposed,which solves incomplete information among game participants.First,vehicle acceleration’s subjective perception evaluation model is used to obtain the initial quantified value of HVs’driving styles in the target lane,which is used for the state space’s confidence of HVs in the Bayesian game lane-changing model.Secondly,the expected safety distance based on the molecular dynamics model is used to solve the game safety benefits.Finally,the Bayesian game is transformed into a complete information static game to solve the Nash equilibrium.By comparing the matching degree of HVs’predicted actions with actual actions,combined with the quantitative indicators of driving styles,the state space’s evaluation confidence is modified.The simulation results show that compared with the K-level game model and the robust K-level game improvement model,the Bayesian game model has a collision rate of 2%in the same traffic environment by using more stringent collision rate statistics standards,which is far lower than the 13%of the K-level game and the 7%of the robust model.The three game models account for 93%,92%and 69%of lane-changing within 3.5 s,respectively.The proposed lane-changing model has a better effect on the decision-making risk control of AVs,and the efficiency of lane-changing within a reasonable time can also be guaranteed.