动态轨迹跟踪下力矩相关性驱动辅助的人机协同转向预测控制策略研究

Research on Human-machine Shared Steering Predictive Control Strategy Assisted with Torque Correlation under Dynamic Trajectory Tracking

针对人机协同转向过程中驾驶员与辅助系统之间协同问题,提出一种基于相关性分析的协同转向预测控制方法。该方法使用记忆型缓存器存储的车辆状态及道路信息,用概率统计方法分析驾驶员输入力矩与辅助力矩的相关性,据此分配人机之间的转向控制权限,并将其引入至转向力矩预测控制策略设计中。同时,针对具有运动不确定的移动障碍物,提出一种实时避障轨迹规划方法。此方法能够根据障碍物运动轨迹变化、避障约束条件等规划出符合要求的最优轨迹,并作为人机协同预测转向控制的目标路径进行跟踪。仿真结果表明,所提出的人机协同预测转向控制方法能够根据驾驶员力矩特性提供对应的辅助力矩,提高了人机协同转向性能,减轻了驾驶员负荷,同时具有较好的跟踪精度和车辆稳定性能;所提出的轨迹规划方法能够获得避开障碍物的实时最优轨迹,结合协同预测转向控制策略实现了对最优轨迹的实时跟踪,形成了具有人机协同预测转向控制功能的集成轨迹规划与跟踪的一体化控制策略。

Aiming at cooperation problem of the human-machine collaborative assistance steering system,a shared steering predictive control method based on correlation analysis is proposed.In this method,the vehicle state and road information stored in memory buffer are used to analyze the correlation between the driver’s input torque and the assistance torque with probability statistics method.It is employed to assign the control authority,and incorporated into the predictive control design of assistant steering torque.At the same time,a real-time obstacle avoidance trajectory planning method is proposed for moving obstacles with uncertainty motion.The optimal trajectory can be obtained according to the change of obstacle trajectory and constraint conditions,and this trajectory can be used as target path tracked by the proposed human-machine cooperative prediction steering controller.The obtained results indicate that:the proposed human-machine shared predictive steering control method can provide the required torque according to the driver’s torque characteristics and improve the collaborative steering performance with reduced driving workload.Additionally,it has better good tracking accuracy and vehicle stability performance.The proposed trajectory planning method can obtain optimal trajectory to avoid obstacles in real-time.Combined with the cooperative predictive steering control strategy,the optimal trajectory is tracked in real-time.It is finally formed as integrated trajectory planning and tracking control strategy with function of human-machine shared predictive steering.