Thermal barrier coating (TBC) is a critical high-temperature protection technology applied to hot-section components of military and civilian aero-engines. Composed of a ceramic oxide top layer and a metallic bond coat

it significantly reduces the substrate operating temperature and offers technical advantages such as high hardness

excellent stability

resistance to high-temperature corrosion

reduces fuel consumption

and improves engine efficiency and service life. After initial preparation via atmospheric plasma spraying

the surface roughness of the coating is relatively high (approximately R

a

10 μm). In production

grinding and polishing post-processing are commonly employed to reduce it to the required range (around R

a

1.6 μm). This study proposes a spline path curve generation and feature point sampling method based on the RANSAC segmentation principle

applicable to robotic automated grinding and polishing of TBC on small turbine blades in aero-engines. The method utilizes a 3D vision sensor to scan the blade surface in real time

generating point cloud data. Through point cloud processing and B-spline curve fitting algorithms

a full-coverage grinding and polishing path for the high-temperature coating on the aero-engine blade surface is generated. Experimental verification demonstrates that this method reduces the coating surface roughness to below R

a

0.7 μm while maintaining effective coating thickness

achieving precision grinding and polishing of TBCs on aero-engine blade surfaces.