Modeling and simulation of planar multibody systems considering multiple revolute clearance joints

This paper presents a general procedure for dynamic modeling and simulation of planar multibody systems considering multiple revolute clearance joints. The normal contact force is evaluated by a hybrid continuous contact force model, established on the base of the Lankarani-Nikravesh (L-N) model and the elastic foundation model. The LuGre friction law is employed to describe the tangential effect. The effectiveness of the presented methodology is demonstrated through the comparisons with the MSC ADAMS software simulation results of a slider-crank mechanism with clearance joints. Then, the system behavior affected by dynamic interaction of three revolute clearance joints is analyzed and some kinds of 27 combination modes are presented. Additionally, a comprehensive analysis of the system responses in a wide range of dynamic simulation parameters is conducted to find out some inner rules existed in the mechanical system with revolute clearance joints. Results show that there exists a strong dynamic interaction between different clearance joints, indicating that all joints should be modeled as imperfect to achieve a further understanding of multibody system behavior. Also, the clearance joint nearer to the input link is found to suffer more serious contact effects, require more input torque and cost longer computational time. Furthermore, the system dynamics relies on many factors, even a small change of which may lead to different system responses, changing from periodic to chaotic and the other way around. In addition, several characteristic values have been captured from the simulation results, which need to be paid more attention in use.