考虑预碰撞时间的自动紧急制动系统分层控制策略研究

为提升汽车的主动安全,对车辆自动紧急制动系统控制策略进行研究。利用分层控制的思想对控制策略进行建模,上层控制器为对车辆制动减速度进行决策的预碰撞时间模型,根据汽车追尾事故深度调查的驾驶员紧急制动数据分析制动系统的制动减速度,在考虑舒适性的条件下确定预碰撞时间阈值。下层控制器按照上层控制器输出的制动减速度,分析车辆轮胎模型和制动系统的关系,通过PID控制调节制动压力对车辆进行控制。在安全评价规程标准工况下验证控制策略的可靠性,通过追尾事故场景的重建来验证控制策略的有效性。仿真结果表明:设计的控制策略在相对车速65 km/h以内时能有效避撞,而高于65 km/h时能最大程度地降低碰撞车速,减小伤害。

Research on Hierarchical Control Strategy for Automatic Emergency Braking System with Consideration of Time-to-collision

In order to enhance the active safety of the vehicle,the control strategy for the vehicle automatic emergency braking system is studied.The control strategy is modeled with the idea of hierarchical control.The upper controller is a time-to-collision model for determining vehicle braking deceleration,which analyze the braking deceleration of brake system based on the drivers emergency braking data of the vehicle rear-end accident depth investigation to determine the time-to-collision threshold with consideration of comfort.The lower controller analyzes the relationship between the tire model and the brake system according to the braking deceleration output from upper controller,and controls the vehicle by adjusting the braking pressure through PID control.The reliability of control strategy is verified under the standard condition of safety evaluation specifications and the effectiveness of the control strategy is validated through the reconstruction of rear-end accident scene.The results of simulation show that the control strategy devised can effectively avoid collisions with a relative speed lower than 65 km/h and can reduce the collision speed to the maximum extent with a relative speed higher than 65 km/h,reducing the severity of damage.