基于三次样条插值谐波叠加技术的随机路面重构方法研究

A study on harmonic superposition method based on cubic spline interpolation of random road reconstruction

汽车虚拟试验仿真研究的关键点在于:如何在获取准确的试验道路信息的基础上重现三维虚拟路面模型,其中道路谱的重构和分析是建立模型的核心内容。首先,以砂石路面为研究对象,对其进行高程数据采集和预处理,获得路面不平度的频谱分布;其次,在谐波叠加法基础上创新性地引入三次样条插值技术,对中心频率点间的互功率谱密度矩阵采取正定平方(Cholesky)分解,并且采用不同条件下的插值方法获取重构功率谱密度模型;最后,通过对谐波叠加法及3类插值重构谱与原始谱的相关系数r的横向对比发现:第1类边界条件下三次样条插值方法在重构精度与效率方面有着明显的优势。此外,基于该方法的拓展性利用软件MATLAB/GUI建立了试验道路谱数据库以及软化操作平台,为车辆虚拟试验仿真提供了可靠支撑。

The key point of vehicle virtual test simulation research is how to reproduce the three-dimensional virtual road model on the basis of obtaining accurate test road information,and the core contents of the model are the reconstruction and analysis of road spectrum.In this paper,the elevation data acquisition and preprocessing of the sand road were carried out,and the spectrum distribution of road roughness was obtained.Secondly,the cubic spline interpolation technique was innovatively introduced on the basis of harmonic superposition method,the mutual power spectral density matrix between the center frequency points was decomposed by Cholesky method,and the reconstructed power spectral density model was obtained by interpolation method under different conditions.Finally,by comparing the correlation coefficient(r) of harmonic superposition method and three kinds of interpolation reconstruction spectrum with the original spectrum,it is found that the cubic spline interpolation method under the first boundary condition has obvious advantages in accuracy and efficiency of reconstruction.In addition,based on the expansion of this method,MATLAB/GUI was used to establish the relevant test road spectrum database and software-based operation platform,which provide reliable support for vehicle virtual test simulation.