小侧偏角下轮胎残余回正力矩算法的研究

Study on Algorithm of Tire Residual Aligning Torque in Small Slip Angle

在轮胎小侧偏角范围(±2°)内,应用线性分析法和多项式拟合曲线法对角度效应残余回正力矩(PRAT)和锥度效应残余回正力矩(CRAT)的测定数据进行分析,通过交叉验证法对1-9阶多项式拟合数据进行判断。结果表明,当侧偏角范围分别为±2°,±1°和±0.5°时,轮胎侧向力和回正力矩分别采用5阶多项式、3阶多项式和线性或2阶多项式拟合方差最小,可求得准确的PRAT和CRAT。

In the range of small slip angle(±2°) of the tire,the linear analysis method and the polynomial fitting curve method were used to analyze the measured data of the ply-steer residual aligning torque(PRAT) and the conicity residual aligning torque(CRAT).The 1-9 order polynomial fitting data was assessed by the cross-validation method.The results showed that when the slip angle range was ±2°,±1° and ±0.5°,the lateral force and the aligning torque of the tire were fitted by the fifth-order polynomial,the third-order polynomial and the linear or second-order polynomial respectively,in which the fitting variance was the smallest,and accurate PRAT and CRAT could be obtained.