Experimental and theoretical study on stick-slip behaviour of contact pair based on real contact state evolution

It is an important subject to establish an accurate kinematic model with friction in mechanics, mechanical engineering and aerospace. Based on the principle of total reflection method, an experimental apparatus for dynamic observation of interface contact behavior is built for studying the evolution of contact state of transparent solid materials during stick slip motion. The displacement difference between the front- end and back-end of the slider in the contact pair stick-slip experiment is analyzed. The evolution of real contact area during stick-slip process is captured by the camera. It is found that in the stick stage, the center area with the largest contact strength in the contact area of interface asperity hardly moved. The displacement difference is mainly caused by the compression deformation of the slider and the micro slip in the local contact area. Based on the evolution rule of real contact area, the analytical model of massdamping-spring model considering stick-slip friction is established. The main contact parameters are determined by experimental identification, and the governing equation of the model is solved by the central difference method. Finally, the numerical results are compared with the experimental results to verify the effectiveness of the model. The model can qualitatively reflect the phenomenon of the displacement difference between the front-end and back-end of slider in stick-slip.