中文摘要：

通过相应的假设和线性处理，建立了线性四自由度汽车列车模型。基于此模型，分析了LQR控制策略，设计了LQR最优控制器。通过Matlab/Simulink和TruckSim联合仿真分析，结果表明：设计的LQR最优控制器能有效地改善汽车列车的机动性和方向稳定性。

英文摘要：

A linear four degree-of-freedom road train model was established through appropriate hypothesis and linear processing.The LQR control strategy was analyzed,and a LQR controller was designed based on the model.By co-simulation of Matlab/Simulink with TruckSim,the results show that the LQR controller can effectively improve the maneuverability and stability of the road train.