考虑轮辙相干性的两种随机路面IFFT生成算法  

Two IFFT-Based Construction Models of 2D Road Roughness Considering the Coherence Function of Different Wheel Tracks

作　　者：王汉平[1] 张哲 廖小华 WANG Han-ping;ZHANG Zhe;LIAO Xiao-hua(School of Aerospace Engineering, Beijing Institute of Technology, Beijing 100081, China)

机构地区：[1]北京理工大学宇航学院,北京100081

出　　处：《北京理工大学学报》2020年第8期835-840,共6页Transactions of Beijing Institute of Technology

基　　金：科技部重点研发计划项目(2018YFF0300804)。

摘　　要：基于不同轮辙路面不平度的自功率谱、互功率谱与其傅里叶变换之间的关系,证明了路面生成的IFFT法与谐波叠加法具有等价性,同时在考虑轮辙相干性的情况下推演了IFFT法中左右轮不平度特性所对应的逆Fourier变换相位角的解析相干关系;也根据左右轮辙功率谱密度阵的LU分解得到了左右轮辙不平度特性的双白噪声滤波传递关系;由此采用IFFT法,分别构建了基于相位角相干性和双白噪声滤波传递关系的两种考虑轮辙相干性的2维随机路面模拟模型.不同轮辙路面模拟结果表明,自功率谱密度几乎重合,左右轮的相干函数也吻合较好,这验证了两模型在路面模拟计算中均具有较高的可信度.Based on the relationship between auto-power spectrum density(PSD),cross-PSD and Fourier transform of road roughness of different wheel tracks,the analytic coherence relation of the phase angle corresponding to inverse Fourier transform(IFT)of road roughness for left and right wheel track in IFFT method.Through LU decomposition of the PSD matrix of road roughness of different wheel tracks,the white noise filter transfer function of the road roughness of left and right wheel track,and then two IFFT models of random road simulation considering the coherence of different wheel tracks.The simulation results show that the auto-PSD and the coherence function of different wheel tracks had high reliability in the simulation of 2D road roughness.

关 键 词：随机路面 逆快速傅里叶变换法 相干函数 功率谱密度 相位角 LU分解 

分 类 号：U461.4[机械工程—车辆工程]