考虑轮胎几何与胎压因素的轮地相互作用力模型及其参数辨识

Tire-Ground Interaction Force Model and Its Parameter Identification Considering Tire Geometry and Pressure

轮地相互作用力对于车辆设计、通过性评价、控制和仿真等方面具有极其重要的作用。传统模型以平板压力为力学假设前提,导致模型中各项参数难以同时响应轮胎几何和胎压因素对轮地相互作用力的影响。采用特定几何和胎压条件下的轮胎弹性形变量建立虚拟刚性轮形,结合轮地接触应力的分布状况,推导一种新的轮地相互力模型。该模型依据轮胎运动状态划分为轮胎准静态压载的垂向载荷模型以及轮胎稳态滑转的牵引力模型,模型中各项参数具有反映轮胎几何、胎压和土壤力学性质之间关联性的特点。通过土槽和原位地面试验对轮地相互作用力模型及其参数辨识结果进行验证,试验结果表明,不同几何尺寸和胎压下的轮胎垂向载荷与试验值之间最大误差不超过0.1 kN,模型参数辨识结果与试验值之间相对误差不超过12%,依据参数辨识结果计算的轮胎牵引力与试验值之间方均根误差为0.37。因而该模型可以有效地应用于考虑轮胎几何和胎压因素的轮地相互作用力学计算中。

Tire-ground interaction plays an important role in vehicle design,trafficability evaluation,control and simulation.The traditional model is based on the assumption of plate pressure,which makes it difficult for the parameters of the model to simultaneously respond to the influence of tire geometry and tire pressure.The virtual rigid wheel shape is established by using the elastic deformation of tire under specific geometry and pressure,and based on the stress distribution of rigid wheel shape,a new tire-ground interaction model is derived.According to tire motion state,the model can be divided into vertical load model with tire quasi-static load and pulling force model with tire steady slip,which can reflect the correlation between tire geometry,tire pressure and soil mechanical properties.The model of tire-ground interaction force and its parameter identification results are validated by soil-bin and in-situ tests.The test results show that the maximum error between calculation and test is not more than 0.1 kN under different tire geometric sizes and tire pressures,and the relative error between the parameter identification result and the test result is less than 12%.The root mean square error between the tire tractive force and the test result is 0.37.Therefore,the model can be effectively applied to the mechanical calculation of tire-ground interaction considering tire geometry and tire pressure.