The Use of Amplitude Measurement in the Diagnosis of Hydraulic Shock Absorbers of Passenger Cars

The article presents the amplitude measurement used in the diagnosis of hydraulic fluid leakage from the shock absorbers of passenger cars. Measures used to assess the distribution of the peak using the free vibration method with force extortion. To verify the results of study the FFT were used. In particular illustration of a random vibroacoustic process, acceleration of sprung mass for front and rear suspension, spectrum of acceleration of sprung mass for front suspension, larger differences of spectrum of acceleration of sprung mass for front suspension are presented in the paper. Analysis results of the of the peak and of the spectrum for the front suspension with losses of shock absorber fluid show decrease in amplitudes of vibrations corresponding increase in shock absorber fluid. Asymmetry of the damping characteristics affects the differences in compression and tension of shock absorber. Spectral analysis is better measure then the study of period. For the rear shock absorbers, differences are smaller. This is due to difference in design of Fiat Seicento front and rear suspension). The presented method of diagnosis requires further study carried out on a large shocks absorbers population to their averaging and comparing test results using different testing methods and estimators and stochastic analysis of vibroacoustic signals.