Study on dynamic characteristics of disc brake system considering the third body

This paper uses dynamic model of the brake system with tangential vibration, which takes into account the disc torsion and the tangential motion of the brake pad. By dividing the area of the three-body contact area and the two-body contact area, the friction generated by each is calculated, and finally the sum of the friction forces in the two areas is calculated, thereby realizing the establishment of a three-body coupling friction model. The two are combined to establish the dynamic model of the automobile disc brake considering the tangential motion of the third-body particles and its differential equations. Based on the nonlinear dynamics theory, using the Stribeck dry friction model, and using the numerical analysis method, the influence of the system's excitation angular velocity and the bifurcation characteristics of the relative velocity between the disc blocks under the influence of the third-body particles is analyzed. It is found that with the gradual increase of the particle size, the system performance is more stable, and for the system vibration, the influence of the particle size on the system vibration mostly comes from the low-speed area. When the system excitation angular velocity reaches a certain value, the particle size has little effect on the system vibration noise.