Research On Post Processing For Vehicle Vibration Signal

Vehicle vibration is one of the most important factors which influence vehicle ride performance and passenger ride comfort. Meanwhile, it is one of the most indices which can obtain predominance in the increasingly drastic market competition for vehicle products. So processing the vehicle vibration signal more effectively and taking measures accordingly to diminish or restrain vehicle vibration have become more and more important. Based on this point, the paper carries through the processing of vehicle vibration signal with twomethods--Fourier Transform and Wavelet Analysis. Firstly, post processingsoftware for vehicle vibration signal has been developed according to the classical FFT transform and spectrum analysis theory based on Visual Basic 6.0. The software, which have undermentioned function: conversion of data file format, display of three dimensions , nephogram display , fiducial frequency processing and data exchange with Matlab, offers a platform for integrated processing for vehicle vibration signal. Then the paper presents the basic theory and engineering comprehension of Wavelet Analysis. The denoising work of vehicle vibration signal with wavelet threshold and research on the twoparameters of wavelet transform--mother wavelet and adjusting tactic ofwavelet coefficients have been done. Fifty mother wavelets of the four discrete wavelet series have been filtered according to the two estimation indices of denoising performance: the plus of Signal-to-Noise Ratio and the denoising gene, and the four mother wavelets of db13, sym11, coif3 and bior6.8 have been selected as better mother wavelets. Aimed at the wavelet coefficient of threshold denoising, it analyzes the trait of traditional soft/hard threshold method and concludes three ameliorative adjusting tactics. Finally, it applies the three methods to denoising work of emulational signal and the true vehicle vibration signal and gets preferable effect.