Automatic Surface Polishing Based on Probe Measurement and Force-Position Decoupling Control

Abstract Automatic polishing is a great application of industrial intelligent manufacturing, which needs not only accurate measurement tools and methods to get the information of polishing surface, but also effective control strategies to ensure better polishing effects. To obtain both the information of the polishing surface and the positional relationship between the object and manipulator, a measuring device composed of a two-degree-of-freedom (DOF) parallel platform equipped with a ruby probe is introduced. Based on the characteristics of the measuring device, an adaptive trajectory generation algorithm for measuring is introduced, and the methods of parameter calibration and accuracy measurement are given. The 3D surface of the polished object is reconstructed by a surface fitting method. The control of position and force directly determines the polishing effect. A force-position decoupling control strategy is developed, that helps keep the normal contact force constant and maintain a tangential feed movement simultaneously. In this paper, the non-standard column in the experiment is polished by a 2DOF parallel measuring device combined with the force-position decoupling control strategy, and the experimental effects of polishing using only the data of the measuring device, polishing using only the force decoupling control strategy and combining the two are compared, and the surface roughness of the workpiece under the comprehensive polishing strategy is given. The result shows that the combination of the measurement and control strategies proposed in this paper can play a great role in automatic polishing.