Dynamic analysis of crank slider mechanism considering 3D translational joint clearance based on variable contact area

This study investigates the influence of joint clearance on the motion accuracy of the slider in the 3D translational pair of the crank slider mechanism. Typically, joint clearance in the kinematic pair can affect the motion accuracy, stability, and service life of multibody mechanical system. The focus of this article is on the 3D translational pair, providing a detailed classification of the contact area between the slider and the guide rail. It summarizes 11 potential contact forms that may occur between these two components. Analyzing the contact states between the slider and guide rail in the 3D translational pair, the study explores three possible contact modes. Based on the geometric characteristics of the contact area between the slider and the guide rail, the mathematical expression for contact stiffness is redefined, considering both front and side contact of the contact area. Combining traditional contact force models with new contact stiffness models, a contact force model between the slider and the guide rail in a 3D translational pair is established, and the dynamics chaotic phenomena of the 3D crank slider mechanism were analyzed. The results indicate that the size of the clearance in the crank slider mechanism and the driving speed of the mechanism are the main factors affecting the dynamics and chaotic phenomena of the mechanism.