Tool Contact State Analysis And Multi Directional Trajectory Process Control Of Robotic Surface Polishing

Polishing is an important process to deal with the workpiece surface in Machining.To ensure high efficiency and stable quality,the study of automatic polishing technology is particularly critical.Different from the milling process,the polishing has smaller material removal and its influencing factors are more complex.The polishing surface quality is mainly affected by polishing force,feed rate,rotational speed and surface curvature.Currently,automatic polishing mainly studies the relationship between various factors and material removal depth,and the planning of polishing trajectory.However,these two aspects of research are not closely linked.The theory of pressure distribution used in the study of material removal model is limited,and the planning of polishing trajectory focuses on it's form but lacks control for it's parameters.In this paper,the contact state of flexible pad is analyzed by CAE,and the material removal model for different types of surfaces are established.And then the multi directional 3D trochoid trajectory is generated on free surface by ABF++ algorithm.Optimizing the polishing process with the trajectory parameters determined by ensuring the material removal is uniform.The content of this paper mainly includes:(1)Establish material removal model of polishing with flexible pad.The contact model of flexible pad with plane and different curvature of surfaces are established in Abaqus.A relation model between the polishing force and working condition is then founded after the analysis of the contact state.Then the pressure distribution in contact area is determined and material removal model of various types of surfaces are set up based on Preston equation.(2)Generate multi directional 3D trochoid trajectory by ABF++ algorithm and do optimization of its parameters.With the flattening algorithm,the 2D trochoid trajectory is generated on the parametric domain,and its discrete points are then mapping back to mesh surface to get the 3D trajectory.And the step and radius of the trochoid trajectory are determined based on the material removal depth model.Finally do simulation and analysis of material removal for single trochoid trajectory.(3)Material removal model and the process effect of multi directional trajectory are validated by robot polishing experiments.Polishing on the plane and spherical surface with straight line path and arc path,then get material removal profiles to verify the removal model.And by polishing on the convex surface with multi directional trochoid trajectory,the optimal effect of polishing process are compared and analyzed to prove the superiority of the automatic polishing technology studied in this paper.