Structure-Borne Shock Absorber Noise: Non-Linear Noise Source Characterization in a Laboratory Environment

The paper describes a technique to qualify and quantify the shock absorber as a non-linear noise source. Unlike other research on suspension components this paper does not identify the shock absorber as a transmission path but as a structure-borne noise source.

The structure-borne noise is originated from the non-linear characteristics of the damper. The force-velocity curve of a damper has been made highly non-linear for passenger comfort purposes. This built in non-linearity and other mechanical properties cause the shock absorber to generate forces in the frequency range of 50..1000 Hz under normal road input conditions. A method is described how to differentiate the shock absorber noise from other noise sources.

Applying the technique one can systematically change components inside the shock absorber and predict the noise reduction in the car cavity without having the car available all the time. A practical example of this research method is elaborated.