Deterministic and Stochastic Characterization of Friction-Induced Vibration in Disc Brakes

The dynamic behavior of a disc brake subjected to a follower frictional force governed by a constant or random friction coefficient is studied. Under a constant frictional load, the circumferential motion is characterized by a quasi-periodic vibration while the transverse deflection exhibits a periodic motion. The numerical simulation indicates that the response amplitude of the circumferential vibration is larger than that of the transverse vibration. Under random frictional load, both transverse and circumferential displacements are found to be essentially non-Gaussian, non-stationary, and narrow-band processes. The energy of the transverse motion considerably concentrates at a dominant frequency. On the other hand, the spectral density of circumferential motion is mainly distributed at two different frequencies.