Brake Moan Simulation using Flexible Methods in Multibody Dynamics 2000-01-2769
Brake noise is challenging to prevent or mitigate because it often interacts with components beyond the foundation brake, such as the axle and suspension. A complete understanding requires a system-level analysis, including elements of the suspension as well as the foundation brake components.
Bosch Braking Systems and Mechanical Dynamics, Inc. have previously used a multibody dynamics approach to simulating low-frequency brake vibrations in ADAMS® . An innovative leap forward has now been taken with the integration of finite element methods into the multibody dynamics simulation. An ADAMS model of a Bosch rear disc brake system was integrated with a flexible suspension trailing arm from MSC/NASTRAN®. A fully non-linear dynamic simulation of brake system behavior, containing rigid and flexible bodies, was performed for a prescribed set of operating conditions. Simulation results (signal frequency and response to known countermeasures and input variations) were validated using data from vehicle experimental testing. Then, the validated model was examined over a prescribed range of operating conditions to determine the effects of parameter variations, predict system-level performance and find parameter values that give desired performance changes.
The model correlated well to physical test data and observations. Spectral analysis of model and test data results show that the frequency content of the model compares very well to that of the test data. Likewise, the model behavior paralleled the physical responses to known countermeasures and input variations. The model is well positioned to be used for further countermeasure studies, or as a guide for predicting the NVH characteristics of similar brake systems currently under development.