基于车辆执行驱动能力的复杂路况速度规划及控制

Speed planning and control under complex road conditions based on vehicle executive capability

为解决复杂道路环境(大曲率、低附着)下满足安全性和高效性约束的车速规划问题,提出了一种基于车辆动力学解析的微分方程规划方法。首先,推导了在稳态转向时满足侧向轮胎力约束的极限速度结构参数表达式。其次,将前轮和后轮的轮胎力执行空间组合为F-F图,得到考虑载荷转移和驱动方式因素的隐式微分方程,并求解该微分方程得到沿路径的极限速度,同时给出了面向离散路径信息的极限速度计算方法。最后,设计了横、纵向协同模型预测控制器,搭建了CarSim和Simulink联合仿真平台,在连续和离散两种信息路径上以规划的极限速度进行轨迹跟踪仿真实验。结果表明,本文提出的极限速度规划方法能够在尽快完成复杂路面环境下轨迹跟踪任务的同时,将轮胎力控制在稳定摩擦圆范围内。

In order to solve the problem of speed planning in complex road environment(large curvature,low adhesion) meeting the constraints of safety and efficiency,a differential equation programming method based on vehicle dynamics was proposed.Firstly,the structural parameter expression of the limit velocity satisfying the lateral tire force constraint was derived in steady-state steering.Secondly,the spatial combination of the tire forces of the front wheel and the rear wheel is shown in the F-F diagram.And the implicit differential equation considering load transfer and driving mode factors was derived.The limit velocity along the path can be obtained by solving the differential equation.A method for calculating the limit speed based on discrete path information was given.Finally,a model prediction controller was designed and a co-simulation platform of CarSim and Simulink was built.The trajectory tracking simulation experiments were carried out with the planned limit speed on the continuous and discrete information paths.The results show that the proposed limit speed planning method can complete the trajectory tracking task as soon as possible in the complex road environment and control the-tire force within the range of stable friction circle.