Frequency domain investigation of brake squeal problem using a low order nonlinear model

The goal of this paper is to investigate the nonlinear dynamics of a low order mathematical model that is developed to study a brake squeal problem. In particular, a two degree of freedom model of a disc brake system is constructed where the brake pad is modeled as a rigid body particle undergoing planar motions, and the disc is represented by a sliding body moving with a constant velocity. Corresponding nonlinear governing equations are obtained, and numerically solved to examine the hammering phenomenon. In order to find the frequency domain response of the system, some of the nonlinear terms apparent in the governing equations are ignored to facilitate solutions. However, only the contact loss nonlinearity is retained to investigate the nature of dynamic system. Equations with the contact loss nonlinearity are then solved using the multi-term harmonic balance method. Shifts in the resonant frequencies during the motion of the pad are clearly observed.