【摘要】 牵引车在承担林业运载作业时，由于林间路况复杂，因此多以低速运行，有较高的转向需求，且往往带有负载单位，所以更关注其行驶稳定性与转向灵敏性。利用CarSim软件构建牵引车物理模型与负载模型，基于Simulink软件进行牵引车控制策略的设计，结合二自由度动力学模型建立牵引车二自由度模型，以牵引车横摆角速度与质心侧偏角参数结合模糊控制理论对牵引车转向过程进行制动力矩反馈控制，另外根据牵引车四轮转向模式，引入前后轮转角比例控制策略。在CarSim-Simulink联合仿真平台下，结合林业作业复杂路况进行不同控制策略下牵引车低速行驶与转向试验。结果表明，采取的控制策略有效减少复杂路况下牵引车的转向半径，提升转向速度，并将质心侧偏角限制在较小范围，牵引车稳定性较高，且横摆角速度稳态值更接近理想状态，转向更加灵敏。更多还原

【Abstract】 When the tractor is undertaking the forestry carrying operation, due to the complex road conditions in the forest, it mostly runs at a low speed, has a high steering demand, and often has a load unit, so it pays more attention to its driving stability and steering sensitivity. In this paper, CarSim software is used to build the physical model and load unit model of the tractor, the control strategy of the tractor is designed based on Simulink software combined with the two-degree-of-freedom dynamic model, and the two-degree-of-freedom model of tractor is established. The braking torque feedback control is carried out by combining the yaw rate and the side deflection angle of centroid with the fuzzy control theory. In addition, the proportional control strategy of front and rear wheel angle is introduced according to the four-wheel steering mode of the tractor. Under the CarSim-Simlulink co-simulation platform, combined with the complex road conditions of forestry operations, the low-speed driving and steering experiments of tractor under different control strategies are carried out. The results show that the control strategy adopted in this paper can effectively reduce the steering radius of the tractor under complex road conditions, increase the steering speed, and limit the side deflection angle of centroid to a small range. The tractor has high stability, the steady state value of yaw rate is closer to the ideal state, and the steering is more sensitive.更多还原