The Study Of Stick-slip Vibration Of Mini Vehicle's Disc Brake

For choosing frictional material and improving design of the automotive brake, the stick-slip vibration characteristic of brake has been investigated Based on the matching pair of the brake.A flexible multi-body model of the brake assembly is established by using Virtual Prototype Technology and Automatic Dynamic Analysis of Mechanical System (ADAMS) as well Finite Element Analysis Software (ANSYS), and used to simulate the braking process and analyze the influence of the stick-slip on the dynamics during the process. The research shows that the braking efficiency increases with raise of dynamic friction coefficient, but the raising amplitude should be controlled within a certain range. The probability to result in stick-slip vibration increases when the friction coefficient reaches up a given value.For exploring the influence of friction pairs on stick-slip vibration, a new stick-slip model to simulate the braking process has been developed based on the tribology with dynamics. By using the model and a serial of negative slope characteristic curves of friction-speed by experiments, the influence of friction pair on the stick - slip vibration was investigated. The results indicate that the higher the hardness of the matching material is, the higher the friction coefficient is, and that the stick-slip vibration easily occurs at low-speed braking conditions.For confirming the theoretical model and analyzing results above, a bench tester and two groups matching pairs were used to study the stick-slip vibration phenomenon. The results indicate that the vibration signals change with friction pair in the braking process, and the higher the hardness of the matching material is, the greater the intensity of vibration signal of the brake is. This shown that the theoretical model in the thesis is correct and can be used in engineering to analyzing the vibration phenomenon of the brake.