Dynamic analysis of a slider-crank mechanism with two types of non-ideal revolute joints

Abstract

Rolling element bearings and journal bearings are typical components comprising a revolute joint in a mechanical system. In the traditional dynamic analysis of multi-body systems, these two types of bearings are generally treated as ideal revolute joints and are modelled by kinematic constraints. The non-linearity of such bearings including internal radial clearance, local contact deformation, friction, lubrication and other phenomena associated with real joints are routinely ignored. In this work, an approach to the dynamic modelling of a multi-body system with these two types of non-ideal revolute joints is outlined. These non-ideal joints were modelled by their force interaction. In rolling element bearings, the frictionless multi-point contacts and bearing kinematics are considered. In the case of a journal bearing, the normal contact force and tangential dry friction force are considered. A planar slider-crank mechanism with multiple non-ideal revolute joints including a rolling ball bearing and two journal bearings is presented as a numerical example to demonstrate application of this approach. The variations of slider kinetic characteristics and the bearing reaction force are used to expound the dynamic characteristics of the mechanism when multiple non-ideal revolute joints are considered.