Dynamic Instability of Rigid Shoe Modes in a Drum Brake System

Abstract

This study examined the dynamic instability of a drum brake induced by the rigid modes of the brake shoe. The brake shoe was modeled as a rigid curved plate subject to frictional contact with a rotating drum. In the presence of a negatively sloped friction curve, dynamic instability was numerically analyzed with respect to variation in the system parameters. The results showed that mode-coupling instability did not occur, but dynamic instability was induced by negative damping in a specific rigid mode, and its propensity varied with the operating conditions and geometric changes.

Keywords

• brake squeal
• drum brake
• rigid mode
• negative slope
• dynamic instability