Summary on the Pseudo-Excitation Method for Vehicle Random Vibration PSD Analysis

Random vibration will take place for vehicles moving on uneven road or railway surfaces.Quick and reliable PSD(power spectral density) analysis for such random vibration is of great importance in order to improve the performance of vehicles.Due to the low efficiency and precision of the conventional random vibration algorithm,previously the vehicles have to be modeled into spring-mass systems with very low degrees of freedom,and so the analysis precision cannot be ensured.Particularly if the fatigue stress concentration is computed,very refined finite element meshes must be adopted,the computational cost will be extremely high and prohibited.In addition,when several wheels are excited simultaneously on different locations of the surface,the MIMO(multi-input-multi-output) random vibration analysis will be even more difficult.Usually,only one or a few samples of the surface unevenness were taken for direct numerical integration,the results were then used to evaluate the statistical characteristics of the vehicle random responses.Clearly,both the precision and efficiency are quite limited.In recent years,the pseudo-excitation method has received much attention in overcoming the above difficulties,and are being used and further developed by many experts in the research fields of cars,trains or even maglevs,which are briefly summarized.