Hertz Model Based Contact Modeling for Joints with Clearance

This paper presents the techniques of contact modeling for revolute joints in flexible multibody systems, in which the dry clearance revolute joints have been coupled with the flexibility of connected bodies. The contact model for revolute joints takes into account the relative planar motion caused by the clearance between the outer and inner races. This model applies a penalty method to simulate the phenomenon of inner-penetration between contact/impact bodies. The relationship between the normal contact force and the inner-penetration is described by the nonlinear Hertz model with energy dissipation. Meanwhile, the friction force can be predicted from continuous Coulomb's law. Finally, an example of flexible multibody systems has been simulated by using the developed contact models.