滤波白噪声路面时域模拟方法与悬架性能仿真

Simulation Method of Road Excitation in Time Domain Using Filtered White Noise and Dynamic Analysis of Suspension

摘要:

为合理模拟路面时域模型，通过路面不平度空间功率谱密度分析路面频域模型，并由路面频域模型推导路面时域模型的滤波白噪声数值模拟方法.提出了采用滤波白噪声方法模拟路面时域模型时，改变仿真车速的同时需调整白噪声采样频率使之与车速相配.通过分析生成的路面时域模型的空间功率谱密度，验证了路面时域模型的准确性.比较只改变车速和所提出的改变车速并调整相应白噪声采样频率模拟的路面时域模型的高度历程、频谱和空间功率谱密度，得到了后者模拟方法更符合标准等级路面的结论.并通过仿真，分析比较了某1/4车辆悬架模型在不同方法生成的路面时域模型输入下的系统响应精确性，体现了所提方法的重要性.

关键词:路面不平度; 路面时域模型; 滤波白噪声; 悬架性能分析

Abstract:

In order to simulate road excitation in time domain appropriately, an analysis was first made on the road excitation in frequency domain based on power spectral density (PSD) of road excitation in spatial frequency. Then a numerical simulation method of road excitation in time domain was derived using filtered white noise. Based on a road excitation simulation in time domain with the filtered white noise method, the sampling frequency of white noise was proposed to be adjusted to the change of the vehicle speed. By analyzing PSD of the generated road excitation in spatial frequency, the generated road excitation in time domain was verified. A comparative study of the road excitation in time domain, and the spectrum as well as the PSD of the road excitations in spatial frequency generated by changing vehicle speed only and that by changing vehicle speed together with the adjusted sampling frequency of white noise show that the latter method agrees well with the standard road classification. A quarter car suspension dynamic performance was simulated with the road excitations generated by different methods, the system response accuracies were compared and analyzed, and thus the importance of the proposed method was validated.

Key words:road surface roughness; road excitation in time domain; filtered white noise; dynamic analysis of suspension