Vibration in an automobile internal rear-view mirror

Finite element models for automobile rear-view mirrors were created to predict mirror vibration response. The models used published and measured material properties and were developed using the ANSYS package. Vibration modes were predicted for the mirror bracket alone and for the complete mirror. All predictions were compared with the results of vibration tests. A detailed study of the mirror clip region (connection to windscreen) was performed to determine its mechanical behaviour. Good agreement was obtained between predicted and measured resonant frequencies and model shapes for both bracket and complete mirror models. The damping characteristics of the bracket material were determined from tests and related to the mirror vibration amplitudes.