Diagnosis and analysis of twin-tube shock absorber rattling noise in electric vehicle

Abstract

To address the rattling noise issue of a Twin-tube hydraulic shock absorber for a electric vehicle, a road test and subjective evaluation were performed. The diagnostic method of the rattling noise source of the shock absorber is studied, and three methods are used to process the test date: the fast Fourier transform can only obtain the main frequency band of the rattling noise; and the short-time Fourier transform can roughly diagnose the frequency band and the occurrence time; using wavelet transform technology combined with displacement signal can accurately lock the source of rattling noise in the rebound stroke. Furthermore, combined with the internal valve configuration of the shock absorber, the rattling noise source is diagnosed in the rebound valve and the compensation valve. The time of rattling noise and the corresponding working stroke of shock absorber can be quickly locked by using the wavelet transform, which is of great significance to solve the problem of shock absorber rattling noise caused by deficiency design of the internal valve architecture of the shock absorber.