Experiment and simulation of micro-part dynamics with roughness effect

In this study, we perform an experiment and develop a dynamic model that describes the planar motion modes of a micro-part, including two linear motions and one rotational motion, on a saw-tooth surface. In the experiment, the planar motion of the micro-part is obtained by a particle-tracking method. The rotation angle is measured from the principal axis of the micro-part image. In a simulation, contact between the micro-part and the saw-tooth surface is assumed to be the contact between a number of hemispheres on the micropart and the surface, which results in either a point contact or slope contact. The effect of the saw-tooth surface roughness on the contact force at each contact point is modeled as a field of normal vectors. In addition, the roughness of the saw-tooth surface is approximated by superposing white noise on an ideal saw-tooth profile and is used to evaluate the adhesion force. The results show that the model describes the motion modes of a micro-part. Furthermore, the simulated results of the two linear motions are in good agreement with our experimental results from a previous study. The proposed model can be used to improve the design of surfaces for micro-part transport.