Automotive Brake Vibration and Squealing Suppression Analysis
Methods in Simulation Design Stage
The brake vibration and squealing problem has been investigated from its occurrence mechanism to systematical analysis method by my group since 1984. The brake system eigenvalue matrix is a non symmetric one due to its frictional coupling parts. So the mismatched system structural design parameters lead to double conjugate complex eigenvalues. The positive real part of complex eigenvalue means that brake system is unstable with the negative damping and self-excited vibration can be occurred, that is the brake vibration and squealing phenomenon.
Our study established a systematical analysis method to identify the most important substructures and their design parameters that should be modified to suppress the vibration and squealing occurrence.
The analytical methods include:
1) Sub structural participation analysis;
2) The substructure modal parameters sensitivity analysis to the real part of squealing modal eigenvalue;
3) Feed-in energy analysis
With above systematic analysis methods, the design target of modification can be formed. The systematic analytical methods have been used for analyzing six cases including 3 cases for drum brake judder and squealing; 3 cases for disk brake low and high frequency squealing and effect of pad shapes. All of them were verified directly or indirectly.
So I wonder if any company wishes to use the system methods in the brake simulation design stage to verify and utilize their values in order for the suppression of brake vibration and squealing occurrence.