The Contact Force Model Of Clearance Revolute Joints With Surface Texturing

With the continuous improvement of the performance of the modern mechanism,the reliability,motion accuracy and working life of the mechanism have been paid more and more attention.The hinged pair is widely used in the mechanism,but it is inevitable to have clearance,and the influence of clearance and its internal collision and friction on the dynamic characteristics of the mechanism is increasingly prominent.Surface texture can improve the tribological properties of motion pairs,which has been proved in engineering.However,there are few reports on the influence of the surface texture and the structure characteristics of the hinged sub-small gap on the contact collision characteristics.In this paper,basic research is carried out on the contact collision problem of the hinged pair gap and the texturized contact surface in the mechanism.And the main tasks have been completed as follows:Firstly,the dynamics modeling of the mechanism with clearance is carried out,and the common contact force models are analyzed and compared.The analysis results show that the improved Winkler contact model is more accurate in solving the small clearance contact problem,which lays a foundation for the subsequent establishment of contact force model considering the surface texture.Combining with the mathematical model of the clearance,the dynamic equation of the multibody system considering the clearance is established,which lays a foundation for analyzing the dynamic characteristics of the mechanism with clearance.Secondly,the geometric model of surface texture is established.Combined with the geometric characteristics of surface texture and the improved Winkler contact model,the model of non-lubricated contact force considering surface texture is established.Based on Reynolds equation,an oil film force model considering the surface texture was established,and a lubricated contact force model considering the surface texture was established on the basis of the non-lubricated contact force model.The contact force model takes the surface texture and lubrication into consideration,and the continuity of the contact force and contact deformation expression is verified by simulation analysis,and the energy loss during contact collision is considered.According to the motion characteristics of hinged accessory elements,a transition force model considering the surface texture and the action of oil film was established.Then the contact force model is compared with other contact force models.The simulation results show that the contact force model is suitable for contact situations with small gap and conformal contact,and can correctly describe the change of energy loss.The model is used to analyze the contact collision process of hinged sub-elements under different initial velocity,texture area and texture depth,and the results show that the contact force model can correctly describe different contact collision processes,which proves the effectiveness of the contact force model.Finally,the established contact force model was integrated into the dynamics equation of the multi-body system,and imported into the multi-body system dynamics simulation software ADAMS.The influence of the surface texture and the influence of the surface texture parameters on the dynamic characteristics of the mechanism were analyzed qualitatively from many angles(clearance size,crank speed,texture area and texture depth).