Chain Drives Modelling Using Kinematic Constraints and Revolute Clearance Joints Formulations

Based on Multibody Dynamics two different formulations for modelling chain drive mechanisms are presented in this work: (i) one in which the revolute joints are considered as ideal joints, modelled as kinematic constraints; (ii) and another in which the kinematic constraints are removed and replaced by a pair of forces representing the contact between the connected bodies, i.e., modelled using the revolute clearance joint formulation. When the chain drive components’ connections are modelled as kinematic joints, the integration of the equations of motion lead to constraint violations that grow to a point at which the chain seems to start vibrating with a very high frequency and ends up disintegrating, even when the Baumgarte stabilization method is used. This problem is, however, eliminated when the interaction between the chain drive components is modelled using the revolute clearance joint formulation, since any constraint violation is exhibited as the number of kinematic constraints used in the multibody model is kept to a minimum.