基于风险评估的自主车辆主动避障预测控制

Predictive control of active obstacle avoidance for autonomous vehicles based on risk assessment

针对自主车辆的主动避障问题,提出一种基于模型预测控制的车辆轨迹规划与跟踪控制方法。为了评估道路结构及不同障碍物对自主车辆的影响,分析不同障碍物的特性并引入风险评估函数。首先,将风险评估函数加入模型预测控制的优化目标函数中,同时考虑车辆动力学特性、车辆物理约束、燃油经济性及舒适性要求;其次,定义自主车辆紧急避障最小转向点,分析车辆进行紧急避障时的行车特性并设计碰撞损失最小控制器;最后,根据行车风险场设计控制器切换机制,实现主动避障控制。所提出的方法在高保真CarSim车辆模型上进行了仿真。

Aiming at the active obstacle avoidance control problems of autonomous vehicles,a vehicle trajectory planning and tracking control method is proposed for the autonomics vehicle based on model predictive control.In order to evaluate the impact of road structure and different obstacles on autonomous vehicles,the characteristics of different obstacles is analysed and a risk assessment function is introduced.Firstly,the risk evaluation functions are embedded into optimization objective functions of model predictive control,while the vehicle dynamic characteristics,vehicle physical constraints,fuel economy and comfort requirements are considered.Then,the minimum turning point of autonomous vehicle for emergency obstacle avoidance is defined and the minimum collision loss controller is designed by analysing the driving characteristics of the vehicle for emergency obstacle avoidance.Finally,the controller switching mechanism is designed to realize the active obstacle avoidance control based on the driving risk field.The proposed method is simulated on a high fidelity CarSim vehicle model.