自 动 驾 驶 汽 车 双 车 道 换 道 最 优 轨 迹 规 划 方 法

For two lane traffic scenarios， a decision-making and optimization-based lane changing trajectory planning method for autonomous vehicles was proposed. Firstly，a risk assessment method based on the Bayesian probability theory was designed to obtain the conditional probability of the lane safety in the current scenario；then，a behavior decision-making method based on the safety utility was designed. According to the risk assessment Bayesian network and decision graph，the behavior decision of lane keeping or lane changing was made. An optimization-based trajectory planning method based on the nonlinear MPC was proposed at the trajectory planning layer，which imitates the excellent driver to give the weight coefficient of each optimized objective function to solve the optimal desired lane changing trajectory. At last，The effectiveness of the decision-making and trajectory planning method was verified by the simulation. The simulation results show that the risk assessment， behavior decision-making and optimization-based trajectory planning method can make the safe behavior decision and plan the optimal lane changing trajectory for autonomous vehicles in different risk scenarios，so that the autonomous vehicle can change the lane safely and quickly.