Calibration and error compensation of scanner-based robotic belt grinding system

Turbine blade is one of the key components of turbomachinery, and the machining quality of its airfoil surface has an important impact on the operating efficiency, service life, and safety of the turbine. Robotic abrasive belt grinding has become an important means of blade airfoil surface machining. Based on the self-developed robot grinding system, this paper proposes a scanner-based system calibration method to determine the relationships among coordinate systems of measurement, robot base, tool, and workpiece. An accurate and efficent calibration method of workpiece coordinate system based on rapid surface segmentation of point cloud using CAD model is established. An blade error surface is constructed by B-spline interpolation to compensate system errors such as absolute positioning error of robot, calibration error, and blade shape error. The calibration process is illustrated at the end of this paper. The effectiveness of the calibration and error compensation methods proposed in this paper are verified by the simulation results.