A model for static contact of revolute cylinder based on geometric constraint and elastic half-space theory

Due to the existence of clearances, contact-impact events are liable to cause lower transmission precision and slower dynamic response of the mechanism involving revolute joints. Based on the elastic-damping method, the continuous contact force (CCF) model is widely used in explicating the contact-impact phenomena. As part of storing and releasing strain energy in the CCF model, the elastic force is equal to the static contact force (SCF) which reflects the purely elastic characteristic of contact objects. Nevertheless, the results calculated by the previous SCF models of revolute joint cannot agree well with the results of static contact experiments based on image method in this paper. An appropriate SCF model of revolute joint was built by the elastic half-space theory, which avoids determining the thickness of elastic layer of the Winkler theory or estimating the deformation of the revolute joint from the external contacting cylinders. Furthermore, the function of distance between contact points was built by the geometric constraint condition which supposes that the two arc lengths from the contacting point to initial contact point are equal. The results of experiment indicates that the proposed model can be used to describe the contact characteristics of a revolute joint exactly.