A robot intelligent polishing system for fiber reinforced plastics (FRP) material combined with online measurement

Abstract

Fiber Reinforced Plastics (FRP) are extensively employed in the fabrication of mannequins. However, the manual polishing process of FRP is characterized by a deficiency in efficiency and poses detrimental effects on the workforce. An industrial robot combined with an online measurement method is proposed for polishing the surface of the mannequin arm made of FPR material. In this paper, the factors affecting the removal depth of FRP materials are discussed by establishing a mathematical model. Based on the simulation analysis, the removal depth and the range of machining parameters are derived. The online measuring device manufactured by Keyence model LJ-X8200 is mounted on the flange of an ABB IRB6700 industrial robot, which obtains the 3D digital data from arm surface before and after the polishing process. A sub-regional hand-eye calibration is applied to establish the spatial transformation matrix from the sensor coordinate to the workpiece coordinate to refine the calibration range and accuracy. Then, the processing data points are extracted by equal interval and coplanar method. In addition, the robot processing posture is obtained from the surface fitting curve based on the least square method. Finally, the polishing processing experiments are performed to analyze robot intelligent location recognition and verify the surface removal effect based on the optimum polishing parameters. Comparing the 3D measuring data before and after the polishing process, it is shown that the average value of workpiece surface roughness has been reduced to 2.518µm.