一种指定功率谱密度与峭度值的对称威布尔分布道路谱重构方法

摘要

The present methods using PSD to reconstruct road spectra can only be used to generate Gaussian road spectra.The lower tail thickness leads to Gaussian PSD curvesare difficult to accurately describe those grim roads with severe road surface fluctuations.According to high-order moment characteristics of Weibull distribution,the method for calculating parameters of Weibull distribution possessing specified kurtosis was derived.Then,based on ZMNL method,a new method using Gaussian white noise to generate stochastic variables with symmetricWeibull distribution possessing specified PSD and kurtosiswas proposed.With this method,several road spectra with varying severity were generated through specifying different kurtoses under the premise of keeping the same PSD function/curve.The correctness and validity of this new method were verified by applying it to reconstruct the road spectrum for a certain road whose reliability was tested.The results provided a new non-Gaussian road modeling method for road and vehicle riding simulation tests.%当前由功率谱密度重构路形谱的方法仅能生成高斯路形谱.高斯分布概率密度分布曲线较低的“拖尾”厚度决定了其难以对各类有着剧烈路面起伏的严酷道路进行有效描述.根据威布尔分布的高阶矩特性,推导了具有指定峭度的威布尔分布参数的计算方法;进而以ZMNL方法为基础,提出了一种由高斯白噪声产生指定功率谱密度与峭度的对称幅度威布尔分布随机变量的方法.使用该方法,可在保持功率谱密度(函数)曲线的前提下,通过指定不同的峭度值,产生不同严酷程度的路形谱.通过将该方法应用于某试验场可靠性试验道路谱重构,验证了该方法的正确性和有效性.为道路模拟试验以及各种车辆仿真试验提供了一种新的非高斯道路模型建模方法.