针对高速工况下四轮独立驱/制动电动车的车道偏离问题，提出一种基于主动转矩分配的车道保持辅助控制方法。该方法的辅助控制系统分为3层，顶层控制器根据人-车-路信息实时进行辅助控制决策，并计算车道保持所需的横摆响应；中层控制器基于滑模控制算法，计算横摆响应跟踪所需的附加横摆力矩；底层控制器通过主动转矩分配产生附加横摆力矩，干预车辆行驶轨迹，以达到车道保持的目的。采用CarSim/Simulink联合仿真进行高速单移线实验验证，结果表明，提出的基于主动转矩分配的四轮独立驱/制动电动车车道保持辅助控制方法，具有良好的车辆动力学稳定性，在高附路面和低附路面上均能够有效地干预车辆行驶轨迹，防止车辆偏离车道。
This paper focuses on the lane keeping assistance system (LKAS) for a four in-wheel motor drive electric vehicle. A new method for lane keeping assistance is presented, which applies additional yaw moment to the electric vehicle to achieve lane maintenance with active distribution of four wheels driving/braking torque. The lane keeping assistance system is divided into three layers. In the upper layer, assistance control decision is made, and the desired yaw rate is calculated by considering vehicle-lane deviation, vehicle dynamic and limitation of road adhesion. In the middle layer, a sliding mode controller (SMC) is designed to control the additional yaw moment. In the lower layer, yaw moment is produced by distributing of drive/brake torques between the four wheels. Lane keeping assistance is carried out by tracking desired yaw response. The LKAS is evaluated via Carsim/Simulink. The simulation result for a single lane change test shows that the proposed method can make the vehicle have good dynamic stability, and can restrict the vehicle within the lane and avoid lane departure accidents.
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