Abstract: Analyzed the reliability of vehicle disc brake system from the view of dependent failure mechanism to improve the reliability calculation accuracy of automobile disc brake system. Fitted failure functions for both the modal failure and the thermal-mechanical coupling failure, based on a finite element analysis with sample data, by using response function method and back propagation (BP) neural network method. Established a correlation model between different failure modes based on Vine Copula model, to estimate the correlation parameters of the system failure modes and to calculate the system reliability at the moment of 1 000, 2 000, 3 000, 4 000, 5 000 h after the vehicle disc brake starts running. The reliability of the system at different moments was simulated for 105 times by using the Monte Carlo method. The results show that the maximum relative error between the simulated value and the calculated value of the model is 0.29%. Therefore, the model meets the accuracy calculation requirements when calculating the reliability of complex mechanical systems.

Key words: vehicle disc brake, dependent failure, approximate fitting, vine copula model, time-varying reliability