This paper presents an approach to predict automotive windscreen wiper chatter noise using the finite element method. In this study, a 3-dimensional finite element model of a real wiper blade is developed and then validated using experimental modal analysis. In order to assess stability of the wiper blade assembly, complex eigenvalue analysis is performed using ABAQUS. The positive real parts of a complex eigenvalue indicate an unstable system. The baseline model is first simulated and stability of the system is examined. Having found a predicted unstable frequency that generates chatter noise, various structural modifications are proposed in order to reduce the vibration.

ABSTRCT:For decades, it has been a challenging task for brake engineers to reduce or totally eliminate squeal that emanates from brake systems. Despite the large number of proposals that have been implemented in tackling disc brake squeal, very few solutions are totally effective to reduce or suppress it. This paper presents an approach to tackle disc brake squeal through chamfered and slotted pad. A three-dimensional FE model of an actual disc brake system is developed. The baseline FE model is first simulated using complex eigenvalue and transient analysis to predict squeal and compared to the squeal tests data obtained in the brake dynamometer. A reasonable correlation is found between these results. Then, three different pad modifications are proposed, simulated and tested. It is shown that pad with chamfers and diagonal slot can totally suppress squeal both in prediction and squeal test.